/******************************************************************************
** This file is an amalgamation of many separate C source files from SQLite
** version 3.8.0.  By combining all the individual C code files into this 
** single large file, the entire code can be compiled as a single translation
** unit.  This allows many compilers to do optimizations that would not be
** possible if the files were compiled separately.  Performance improvements
** of 5% or more are commonly seen when SQLite is compiled as a single
** translation unit.
**
** This file is all you need to compile SQLite.  To use SQLite in other
................................................................................
#define SQLITE_AMALGAMATION 1
#ifndef SQLITE_PRIVATE
# define SQLITE_PRIVATE static
#endif
#ifndef SQLITE_API
# define SQLITE_API
#endif
/************** Begin file sqliteInt.h ***************************************/
/*
** 2001 September 15
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_

/*
** These #defines should enable >2GB file support on POSIX if the
** underlying operating system supports it.  If the OS lacks
** large file support, or if the OS is windows, these should be no-ops.
**
** Ticket #2739:  The _LARGEFILE_SOURCE macro must appear before any
** system #includes.  Hence, this block of code must be the very first
** code in all source files.
**
** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch
** on the compiler command line.  This is necessary if you are compiling
** on a recent machine (ex: Red Hat 7.2) but you want your code to work
** on an older machine (ex: Red Hat 6.0).  If you compile on Red Hat 7.2
** without this option, LFS is enable.  But LFS does not exist in the kernel
** in Red Hat 6.0, so the code won't work.  Hence, for maximum binary
** portability you should omit LFS.
**
** Similar is true for Mac OS X.  LFS is only supported on Mac OS X 9 and later.
*/
#ifndef SQLITE_DISABLE_LFS
# define _LARGE_FILE       1
# ifndef _FILE_OFFSET_BITS
#   define _FILE_OFFSET_BITS 64
# endif
# define _LARGEFILE_SOURCE 1
#endif

/*
** Include the configuration header output by 'configure' if we're using the
** autoconf-based build
*/
#ifdef _HAVE_SQLITE_CONFIG_H
#include "config.h"
#endif

/************** Include sqliteLimit.h in the middle of sqliteInt.h ***********/
/************** Begin file sqliteLimit.h *************************************/
/*
** 2007 May 7
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** 
** This file defines various limits of what SQLite can process.
*/

/*
** The maximum length of a TEXT or BLOB in bytes.   This also
** limits the size of a row in a table or index.
**
** The hard limit is the ability of a 32-bit signed integer
** to count the size: 2^31-1 or 2147483647.
*/
#ifndef SQLITE_MAX_LENGTH
# define SQLITE_MAX_LENGTH 1000000000
#endif

/*
** This is the maximum number of
**
**    * Columns in a table
**    * Columns in an index
**    * Columns in a view
**    * Terms in the SET clause of an UPDATE statement
**    * Terms in the result set of a SELECT statement
**    * Terms in the GROUP BY or ORDER BY clauses of a SELECT statement.
**    * Terms in the VALUES clause of an INSERT statement
**
** The hard upper limit here is 32676.  Most database people will
** tell you that in a well-normalized database, you usually should
** not have more than a dozen or so columns in any table.  And if
** that is the case, there is no point in having more than a few
** dozen values in any of the other situations described above.
*/
#ifndef SQLITE_MAX_COLUMN
# define SQLITE_MAX_COLUMN 2000
#endif

/*
** The maximum length of a single SQL statement in bytes.
**
** It used to be the case that setting this value to zero would
** turn the limit off.  That is no longer true.  It is not possible
** to turn this limit off.
*/
#ifndef SQLITE_MAX_SQL_LENGTH
# define SQLITE_MAX_SQL_LENGTH 1000000000
#endif

/*
** The maximum depth of an expression tree. This is limited to 
** some extent by SQLITE_MAX_SQL_LENGTH. But sometime you might 
** want to place more severe limits on the complexity of an 
** expression.
**
** A value of 0 used to mean that the limit was not enforced.
** But that is no longer true.  The limit is now strictly enforced
** at all times.
*/
#ifndef SQLITE_MAX_EXPR_DEPTH
# define SQLITE_MAX_EXPR_DEPTH 1000
#endif

/*
** The maximum number of terms in a compound SELECT statement.
** The code generator for compound SELECT statements does one
** level of recursion for each term.  A stack overflow can result
** if the number of terms is too large.  In practice, most SQL
** never has more than 3 or 4 terms.  Use a value of 0 to disable
** any limit on the number of terms in a compount SELECT.
*/
#ifndef SQLITE_MAX_COMPOUND_SELECT
# define SQLITE_MAX_COMPOUND_SELECT 500
#endif

/*
** The maximum number of opcodes in a VDBE program.
** Not currently enforced.
*/
#ifndef SQLITE_MAX_VDBE_OP
# define SQLITE_MAX_VDBE_OP 25000
#endif

/*
** The maximum number of arguments to an SQL function.
*/
#ifndef SQLITE_MAX_FUNCTION_ARG
# define SQLITE_MAX_FUNCTION_ARG 127
#endif

/*
** The maximum number of in-memory pages to use for the main database
** table and for temporary tables.  The SQLITE_DEFAULT_CACHE_SIZE
*/
#ifndef SQLITE_DEFAULT_CACHE_SIZE
# define SQLITE_DEFAULT_CACHE_SIZE  2000
#endif
#ifndef SQLITE_DEFAULT_TEMP_CACHE_SIZE
# define SQLITE_DEFAULT_TEMP_CACHE_SIZE  500
#endif

/*
** The default number of frames to accumulate in the log file before
** checkpointing the database in WAL mode.
*/
#ifndef SQLITE_DEFAULT_WAL_AUTOCHECKPOINT
# define SQLITE_DEFAULT_WAL_AUTOCHECKPOINT  1000
#endif

/*
** The maximum number of attached databases.  This must be between 0
** and 62.  The upper bound on 62 is because a 64-bit integer bitmap
** is used internally to track attached databases.
*/
#ifndef SQLITE_MAX_ATTACHED
# define SQLITE_MAX_ATTACHED 10
#endif


/*
** The maximum value of a ?nnn wildcard that the parser will accept.
*/
#ifndef SQLITE_MAX_VARIABLE_NUMBER
# define SQLITE_MAX_VARIABLE_NUMBER 999
#endif

/* Maximum page size.  The upper bound on this value is 65536.  This a limit
** imposed by the use of 16-bit offsets within each page.
**
** Earlier versions of SQLite allowed the user to change this value at
** compile time. This is no longer permitted, on the grounds that it creates
** a library that is technically incompatible with an SQLite library 
** compiled with a different limit. If a process operating on a database 
** with a page-size of 65536 bytes crashes, then an instance of SQLite 
** compiled with the default page-size limit will not be able to rollback 
** the aborted transaction. This could lead to database corruption.
*/
#ifdef SQLITE_MAX_PAGE_SIZE
# undef SQLITE_MAX_PAGE_SIZE
#endif
#define SQLITE_MAX_PAGE_SIZE 65536


/*
** The default size of a database page.
*/
#ifndef SQLITE_DEFAULT_PAGE_SIZE
# define SQLITE_DEFAULT_PAGE_SIZE 1024
#endif
#if SQLITE_DEFAULT_PAGE_SIZE>SQLITE_MAX_PAGE_SIZE
# undef SQLITE_DEFAULT_PAGE_SIZE
# define SQLITE_DEFAULT_PAGE_SIZE SQLITE_MAX_PAGE_SIZE
#endif

/*
** Ordinarily, if no value is explicitly provided, SQLite creates databases
** with page size SQLITE_DEFAULT_PAGE_SIZE. However, based on certain
** device characteristics (sector-size and atomic write() support),
** SQLite may choose a larger value. This constant is the maximum value
** SQLite will choose on its own.
*/
#ifndef SQLITE_MAX_DEFAULT_PAGE_SIZE
# define SQLITE_MAX_DEFAULT_PAGE_SIZE 8192
#endif
#if SQLITE_MAX_DEFAULT_PAGE_SIZE>SQLITE_MAX_PAGE_SIZE
# undef SQLITE_MAX_DEFAULT_PAGE_SIZE
# define SQLITE_MAX_DEFAULT_PAGE_SIZE SQLITE_MAX_PAGE_SIZE
#endif


/*
** Maximum number of pages in one database file.
**
** This is really just the default value for the max_page_count pragma.
** This value can be lowered (or raised) at run-time using that the
** max_page_count macro.
*/
#ifndef SQLITE_MAX_PAGE_COUNT
# define SQLITE_MAX_PAGE_COUNT 1073741823
#endif

/*
** Maximum length (in bytes) of the pattern in a LIKE or GLOB
** operator.
*/
#ifndef SQLITE_MAX_LIKE_PATTERN_LENGTH
# define SQLITE_MAX_LIKE_PATTERN_LENGTH 50000
#endif

/*
** Maximum depth of recursion for triggers.
**
** A value of 1 means that a trigger program will not be able to itself
** fire any triggers. A value of 0 means that no trigger programs at all 
** may be executed.
*/
#ifndef SQLITE_MAX_TRIGGER_DEPTH
# define SQLITE_MAX_TRIGGER_DEPTH 1000
#endif

/************** End of sqliteLimit.h *****************************************/
/************** Continuing where we left off in sqliteInt.h ******************/

/* Disable nuisance warnings on Borland compilers */
#if defined(__BORLANDC__)
#pragma warn -rch /* unreachable code */
#pragma warn -ccc /* Condition is always true or false */
#pragma warn -aus /* Assigned value is never used */
#pragma warn -csu /* Comparing signed and unsigned */
#pragma warn -spa /* Suspicious pointer arithmetic */
#endif

/* Needed for various definitions... */
#ifndef _GNU_SOURCE
# define _GNU_SOURCE
#endif

#if defined(__OpenBSD__) && !defined(_BSD_SOURCE)
# define _BSD_SOURCE
#endif

/*
** Include standard header files as necessary
*/
#ifdef HAVE_STDINT_H
#include <stdint.h>
#endif
#ifdef HAVE_INTTYPES_H
#include <inttypes.h>
#endif

/*
** The following macros are used to cast pointers to integers and
** integers to pointers.  The way you do this varies from one compiler
** to the next, so we have developed the following set of #if statements
** to generate appropriate macros for a wide range of compilers.
**
** The correct "ANSI" way to do this is to use the intptr_t type. 
** Unfortunately, that typedef is not available on all compilers, or
** if it is available, it requires an #include of specific headers
** that vary from one machine to the next.
**
** Ticket #3860:  The llvm-gcc-4.2 compiler from Apple chokes on
** the ((void*)&((char*)0)[X]) construct.  But MSVC chokes on ((void*)(X)).
** So we have to define the macros in different ways depending on the
** compiler.
*/
#if defined(__PTRDIFF_TYPE__)  /* This case should work for GCC */
# define SQLITE_INT_TO_PTR(X)  ((void*)(__PTRDIFF_TYPE__)(X))
# define SQLITE_PTR_TO_INT(X)  ((int)(__PTRDIFF_TYPE__)(X))
#elif !defined(__GNUC__)       /* Works for compilers other than LLVM */
# define SQLITE_INT_TO_PTR(X)  ((void*)&((char*)0)[X])
# define SQLITE_PTR_TO_INT(X)  ((int)(((char*)X)-(char*)0))
#elif defined(HAVE_STDINT_H)   /* Use this case if we have ANSI headers */
# define SQLITE_INT_TO_PTR(X)  ((void*)(intptr_t)(X))
# define SQLITE_PTR_TO_INT(X)  ((int)(intptr_t)(X))
#else                          /* Generates a warning - but it always works */
# define SQLITE_INT_TO_PTR(X)  ((void*)(X))
# define SQLITE_PTR_TO_INT(X)  ((int)(X))
#endif

/*
** The SQLITE_THREADSAFE macro must be defined as 0, 1, or 2.
** 0 means mutexes are permanently disable and the library is never
** threadsafe.  1 means the library is serialized which is the highest
** level of threadsafety.  2 means the library is multithreaded - multiple
** threads can use SQLite as long as no two threads try to use the same
** database connection at the same time.
**
** Older versions of SQLite used an optional THREADSAFE macro.
** We support that for legacy.
*/
#if !defined(SQLITE_THREADSAFE)
# if defined(THREADSAFE)
#   define SQLITE_THREADSAFE THREADSAFE
# else
#   define SQLITE_THREADSAFE 1 /* IMP: R-07272-22309 */
# endif
#endif

/*
** Powersafe overwrite is on by default.  But can be turned off using
** the -DSQLITE_POWERSAFE_OVERWRITE=0 command-line option.
*/
#ifndef SQLITE_POWERSAFE_OVERWRITE
# define SQLITE_POWERSAFE_OVERWRITE 1
#endif

/*
** The SQLITE_DEFAULT_MEMSTATUS macro must be defined as either 0 or 1.
** It determines whether or not the features related to 
** SQLITE_CONFIG_MEMSTATUS are available by default or not. This value can
** be overridden at runtime using the sqlite3_config() API.
*/
#if !defined(SQLITE_DEFAULT_MEMSTATUS)
# define SQLITE_DEFAULT_MEMSTATUS 1
#endif

/*
** Exactly one of the following macros must be defined in order to
** specify which memory allocation subsystem to use.
**
**     SQLITE_SYSTEM_MALLOC          // Use normal system malloc()
**     SQLITE_WIN32_MALLOC           // Use Win32 native heap API
**     SQLITE_ZERO_MALLOC            // Use a stub allocator that always fails
**     SQLITE_MEMDEBUG               // Debugging version of system malloc()
**
** On Windows, if the SQLITE_WIN32_MALLOC_VALIDATE macro is defined and the
** assert() macro is enabled, each call into the Win32 native heap subsystem
** will cause HeapValidate to be called.  If heap validation should fail, an
** assertion will be triggered.
**
** If none of the above are defined, then set SQLITE_SYSTEM_MALLOC as
** the default.
*/
#if defined(SQLITE_SYSTEM_MALLOC) \
  + defined(SQLITE_WIN32_MALLOC) \
  + defined(SQLITE_ZERO_MALLOC) \
  + defined(SQLITE_MEMDEBUG)>1
# error "Two or more of the following compile-time configuration options\
 are defined but at most one is allowed:\
 SQLITE_SYSTEM_MALLOC, SQLITE_WIN32_MALLOC, SQLITE_MEMDEBUG,\
 SQLITE_ZERO_MALLOC"
#endif
#if defined(SQLITE_SYSTEM_MALLOC) \
  + defined(SQLITE_WIN32_MALLOC) \
  + defined(SQLITE_ZERO_MALLOC) \
  + defined(SQLITE_MEMDEBUG)==0
# define SQLITE_SYSTEM_MALLOC 1
#endif

/*
** If SQLITE_MALLOC_SOFT_LIMIT is not zero, then try to keep the
** sizes of memory allocations below this value where possible.
*/
#if !defined(SQLITE_MALLOC_SOFT_LIMIT)
# define SQLITE_MALLOC_SOFT_LIMIT 1024
#endif

/*
** We need to define _XOPEN_SOURCE as follows in order to enable
** recursive mutexes on most Unix systems and fchmod() on OpenBSD.
** But _XOPEN_SOURCE define causes problems for Mac OS X, so omit
** it.
*/
#if !defined(_XOPEN_SOURCE) && !defined(__DARWIN__) && !defined(__APPLE__)
#  define _XOPEN_SOURCE 600
#endif

/*
** NDEBUG and SQLITE_DEBUG are opposites.  It should always be true that
** defined(NDEBUG)==!defined(SQLITE_DEBUG).  If this is not currently true,
** make it true by defining or undefining NDEBUG.
**
** Setting NDEBUG makes the code smaller and faster by disabling the
** assert() statements in the code.  So we want the default action
** to be for NDEBUG to be set and NDEBUG to be undefined only if SQLITE_DEBUG
** is set.  Thus NDEBUG becomes an opt-in rather than an opt-out
** feature.
*/
#if !defined(NDEBUG) && !defined(SQLITE_DEBUG) 
# define NDEBUG 1
#endif
#if defined(NDEBUG) && defined(SQLITE_DEBUG)
# undef NDEBUG
#endif

/*
** The testcase() macro is used to aid in coverage testing.  When 
** doing coverage testing, the condition inside the argument to
** testcase() must be evaluated both true and false in order to
** get full branch coverage.  The testcase() macro is inserted
** to help ensure adequate test coverage in places where simple
** condition/decision coverage is inadequate.  For example, testcase()
** can be used to make sure boundary values are tested.  For
** bitmask tests, testcase() can be used to make sure each bit
** is significant and used at least once.  On switch statements
** where multiple cases go to the same block of code, testcase()
** can insure that all cases are evaluated.
**
*/
#ifdef SQLITE_COVERAGE_TEST
SQLITE_PRIVATE   void sqlite3Coverage(int);
# define testcase(X)  if( X ){ sqlite3Coverage(__LINE__); }
#else
# define testcase(X)
#endif

/*
** The TESTONLY macro is used to enclose variable declarations or
** other bits of code that are needed to support the arguments
** within testcase() and assert() macros.
*/
#if !defined(NDEBUG) || defined(SQLITE_COVERAGE_TEST)
# define TESTONLY(X)  X
#else
# define TESTONLY(X)
#endif

/*
** Sometimes we need a small amount of code such as a variable initialization
** to setup for a later assert() statement.  We do not want this code to
** appear when assert() is disabled.  The following macro is therefore
** used to contain that setup code.  The "VVA" acronym stands for
** "Verification, Validation, and Accreditation".  In other words, the
** code within VVA_ONLY() will only run during verification processes.
*/
#ifndef NDEBUG
# define VVA_ONLY(X)  X
#else
# define VVA_ONLY(X)
#endif

/*
** The ALWAYS and NEVER macros surround boolean expressions which 
** are intended to always be true or false, respectively.  Such
** expressions could be omitted from the code completely.  But they
** are included in a few cases in order to enhance the resilience
** of SQLite to unexpected behavior - to make the code "self-healing"
** or "ductile" rather than being "brittle" and crashing at the first
** hint of unplanned behavior.
**
** In other words, ALWAYS and NEVER are added for defensive code.
**
** When doing coverage testing ALWAYS and NEVER are hard-coded to
** be true and false so that the unreachable code they specify will
** not be counted as untested code.
*/
#if defined(SQLITE_COVERAGE_TEST)
# define ALWAYS(X)      (1)
# define NEVER(X)       (0)
#elif !defined(NDEBUG)
# define ALWAYS(X)      ((X)?1:(assert(0),0))
# define NEVER(X)       ((X)?(assert(0),1):0)
#else
# define ALWAYS(X)      (X)
# define NEVER(X)       (X)
#endif

/*
** Return true (non-zero) if the input is a integer that is too large
** to fit in 32-bits.  This macro is used inside of various testcase()
** macros to verify that we have tested SQLite for large-file support.
*/
#define IS_BIG_INT(X)  (((X)&~(i64)0xffffffff)!=0)

/*
** The macro unlikely() is a hint that surrounds a boolean
** expression that is usually false.  Macro likely() surrounds
** a boolean expression that is usually true.  These hints could,
** in theory, be used by the compiler to generate better code, but
** currently they are just comments for human readers.
*/
#define likely(X)    (X)
#define unlikely(X)  (X)

/************** Include sqlite3.h in the middle of sqliteInt.h ***************/
/************** Begin file sqlite3.h *****************************************/
/*
** 2001 September 15
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
................................................................................
** string contains the date and time of the check-in (UTC) and an SHA1
** hash of the entire source tree.
**
** See also: [sqlite3_libversion()],
** [sqlite3_libversion_number()], [sqlite3_sourceid()],
** [sqlite_version()] and [sqlite_source_id()].
*/
#define SQLITE_VERSION        "3.8.0"
#define SQLITE_VERSION_NUMBER 3008000
#define SQLITE_SOURCE_ID      "2013-08-22 02:56:28 0775501acf152dcbf4dd039f4511f3d8c4330d85"

/*
** CAPI3REF: Run-Time Library Version Numbers
** KEYWORDS: sqlite3_version, sqlite3_sourceid
**
** These interfaces provide the same information as the [SQLITE_VERSION],
** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
................................................................................
#define SQLITE_IOERR_SHMSIZE           (SQLITE_IOERR | (19<<8))
#define SQLITE_IOERR_SHMLOCK           (SQLITE_IOERR | (20<<8))
#define SQLITE_IOERR_SHMMAP            (SQLITE_IOERR | (21<<8))
#define SQLITE_IOERR_SEEK              (SQLITE_IOERR | (22<<8))
#define SQLITE_IOERR_DELETE_NOENT      (SQLITE_IOERR | (23<<8))
#define SQLITE_IOERR_MMAP              (SQLITE_IOERR | (24<<8))
#define SQLITE_IOERR_GETTEMPPATH       (SQLITE_IOERR | (25<<8))

#define SQLITE_LOCKED_SHAREDCACHE      (SQLITE_LOCKED |  (1<<8))
#define SQLITE_BUSY_RECOVERY           (SQLITE_BUSY   |  (1<<8))
#define SQLITE_BUSY_SNAPSHOT           (SQLITE_BUSY   |  (2<<8))
#define SQLITE_CANTOPEN_NOTEMPDIR      (SQLITE_CANTOPEN | (1<<8))
#define SQLITE_CANTOPEN_ISDIR          (SQLITE_CANTOPEN | (2<<8))
#define SQLITE_CANTOPEN_FULLPATH       (SQLITE_CANTOPEN | (3<<8))

#define SQLITE_CORRUPT_VTAB            (SQLITE_CORRUPT | (1<<8))
#define SQLITE_READONLY_RECOVERY       (SQLITE_READONLY | (1<<8))
#define SQLITE_READONLY_CANTLOCK       (SQLITE_READONLY | (2<<8))
#define SQLITE_READONLY_ROLLBACK       (SQLITE_READONLY | (3<<8))
#define SQLITE_ABORT_ROLLBACK          (SQLITE_ABORT | (2<<8))
#define SQLITE_CONSTRAINT_CHECK        (SQLITE_CONSTRAINT | (1<<8))
#define SQLITE_CONSTRAINT_COMMITHOOK   (SQLITE_CONSTRAINT | (2<<8))
................................................................................
** log message after formatting via [sqlite3_snprintf()].
** The SQLite logging interface is not reentrant; the logger function
** supplied by the application must not invoke any SQLite interface.
** In a multi-threaded application, the application-defined logger
** function must be threadsafe. </dd>
**
** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI
** <dd> This option takes a single argument of type int. If non-zero, then
** URI handling is globally enabled. If the parameter is zero, then URI handling
** is globally disabled. If URI handling is globally enabled, all filenames
** passed to [sqlite3_open()], [sqlite3_open_v2()], [sqlite3_open16()] or
** specified as part of [ATTACH] commands are interpreted as URIs, regardless
** of whether or not the [SQLITE_OPEN_URI] flag is set when the database
** connection is opened. If it is globally disabled, filenames are
** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the
** database connection is opened. By default, URI handling is globally
** disabled. The default value may be changed by compiling with the
** [SQLITE_USE_URI] symbol defined.
**
** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN
** <dd> This option takes a single integer argument which is interpreted as
** a boolean in order to enable or disable the use of covering indices for
** full table scans in the query optimizer.  The default setting is determined
** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on"
** if that compile-time option is omitted.
** The ability to disable the use of covering indices for full table scans
** is because some incorrectly coded legacy applications might malfunction
** malfunction when the optimization is enabled.  Providing the ability to
** disable the optimization allows the older, buggy application code to work
** without change even with newer versions of SQLite.
**
** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE
** <dd> These options are obsolete and should not be used by new code.
** They are retained for backwards compatibility but are now no-ops.
................................................................................
** the connection being passed as the second parameter is being closed. The
** third parameter is passed NULL In this case.  An example of using this
** configuration option can be seen in the "test_sqllog.c" source file in
** the canonical SQLite source tree.</dd>
**
** [[SQLITE_CONFIG_MMAP_SIZE]]
** <dt>SQLITE_CONFIG_MMAP_SIZE
** <dd>SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values
** that are the default mmap size limit (the default setting for
** [PRAGMA mmap_size]) and the maximum allowed mmap size limit.
** The default setting can be overridden by each database connection using
** either the [PRAGMA mmap_size] command, or by using the
** [SQLITE_FCNTL_MMAP_SIZE] file control.  The maximum allowed mmap size
** cannot be changed at run-time.  Nor may the maximum allowed mmap size
** exceed the compile-time maximum mmap size set by the
** [SQLITE_MAX_MMAP_SIZE] compile-time option.  
** If either argument to this option is negative, then that argument is
** changed to its compile-time default.
** </dl>
*/
#define SQLITE_CONFIG_SINGLETHREAD  1  /* nil */
#define SQLITE_CONFIG_MULTITHREAD   2  /* nil */
#define SQLITE_CONFIG_SERIALIZED    3  /* nil */
#define SQLITE_CONFIG_MALLOC        4  /* sqlite3_mem_methods* */
................................................................................
}  /* end of the 'extern "C"' block */
#endif

#endif  /* ifndef _SQLITE3RTREE_H_ */


/************** End of sqlite3.h *********************************************/









































































































































































































































































/************** Continuing where we left off in sqliteInt.h ******************/






























































































































































































































































/************** Include hash.h in the middle of sqliteInt.h ******************/
/************** Begin file hash.h ********************************************/
/*
** 2001 September 22
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
................................................................................
*/
#ifdef SQLITE_64BIT_STATS
 typedef u64 tRowcnt;    /* 64-bit only if requested at compile-time */
#else
 typedef u32 tRowcnt;    /* 32-bit is the default */
#endif


























/*
** Macros to determine whether the machine is big or little endian,
** evaluated at runtime.
*/
#ifdef SQLITE_AMALGAMATION
SQLITE_PRIVATE const int sqlite3one = 1;
#else
................................................................................
# define SQLITE_DEFAULT_MMAP_SIZE_xc 1  /* Exclude from ctime.c */
#endif
#if SQLITE_DEFAULT_MMAP_SIZE>SQLITE_MAX_MMAP_SIZE
# undef SQLITE_DEFAULT_MMAP_SIZE
# define SQLITE_DEFAULT_MMAP_SIZE SQLITE_MAX_MMAP_SIZE
#endif















/*
** An instance of the following structure is used to store the busy-handler
** callback for a given sqlite handle. 
**
** The sqlite.busyHandler member of the sqlite struct contains the busy
** callback for the database handle. Each pager opened via the sqlite
** handle is passed a pointer to sqlite.busyHandler. The busy-handler
................................................................................
  int (*xWalCallback)(void *, sqlite3 *, const char *, int);
  void *pWalArg;
#endif
  void(*xCollNeeded)(void*,sqlite3*,int eTextRep,const char*);
  void(*xCollNeeded16)(void*,sqlite3*,int eTextRep,const void*);
  void *pCollNeededArg;
  sqlite3_value *pErr;          /* Most recent error message */
  char *zErrMsg;                /* Most recent error message (UTF-8 encoded) */
  char *zErrMsg16;              /* Most recent error message (UTF-16 encoded) */
  union {
    volatile int isInterrupted; /* True if sqlite3_interrupt has been called */
    double notUsed1;            /* Spacer */
  } u1;
  Lookaside lookaside;          /* Lookaside malloc configuration */
#ifndef SQLITE_OMIT_AUTHORIZATION
  int (*xAuth)(void*,int,const char*,const char*,const char*,const char*);
................................................................................
#define SQLITE_DistinctOpt    0x0020   /* DISTINCT using indexes */
#define SQLITE_CoverIdxScan   0x0040   /* Covering index scans */
#define SQLITE_OrderByIdxJoin 0x0080   /* ORDER BY of joins via index */
#define SQLITE_SubqCoroutine  0x0100   /* Evaluate subqueries as coroutines */
#define SQLITE_Transitive     0x0200   /* Transitive constraints */
#define SQLITE_OmitNoopJoin   0x0400   /* Omit unused tables in joins */
#define SQLITE_Stat3          0x0800   /* Use the SQLITE_STAT3 table */

#define SQLITE_AllOpts        0xffff   /* All optimizations */

/*
** Macros for testing whether or not optimizations are enabled or disabled.
*/
#ifndef SQLITE_OMIT_BUILTIN_TEST
#define OptimizationDisabled(db, mask)  (((db)->dbOptFlags&(mask))!=0)
................................................................................
** Each SQL function is defined by an instance of the following
** structure.  A pointer to this structure is stored in the sqlite.aFunc
** hash table.  When multiple functions have the same name, the hash table
** points to a linked list of these structures.
*/
struct FuncDef {
  i16 nArg;            /* Number of arguments.  -1 means unlimited */
  u8 iPrefEnc;         /* Preferred text encoding (SQLITE_UTF8, 16LE, 16BE) */
  u8 flags;            /* Some combination of SQLITE_FUNC_* */
  void *pUserData;     /* User data parameter */
  FuncDef *pNext;      /* Next function with same name */
  void (*xFunc)(sqlite3_context*,int,sqlite3_value**); /* Regular function */
  void (*xStep)(sqlite3_context*,int,sqlite3_value**); /* Aggregate step */
  void (*xFinalize)(sqlite3_context*);                /* Aggregate finalizer */
  char *zName;         /* SQL name of the function. */
  FuncDef *pHash;      /* Next with a different name but the same hash */
................................................................................
};

/*
** Possible values for FuncDef.flags.  Note that the _LENGTH and _TYPEOF
** values must correspond to OPFLAG_LENGTHARG and OPFLAG_TYPEOFARG.  There
** are assert() statements in the code to verify this.
*/

#define SQLITE_FUNC_LIKE     0x01 /* Candidate for the LIKE optimization */
#define SQLITE_FUNC_CASE     0x02 /* Case-sensitive LIKE-type function */
#define SQLITE_FUNC_EPHEM    0x04 /* Ephemeral.  Delete with VDBE */
#define SQLITE_FUNC_NEEDCOLL 0x08 /* sqlite3GetFuncCollSeq() might be called */
#define SQLITE_FUNC_COUNT    0x10 /* Built-in count(*) aggregate */
#define SQLITE_FUNC_COALESCE 0x20 /* Built-in coalesce() or ifnull() function */
#define SQLITE_FUNC_LENGTH   0x40 /* Built-in length() function */
#define SQLITE_FUNC_TYPEOF   0x80 /* Built-in typeof() function */




/*
** The following three macros, FUNCTION(), LIKEFUNC() and AGGREGATE() are
** used to create the initializers for the FuncDef structures.
**
**   FUNCTION(zName, nArg, iArg, bNC, xFunc)
**     Used to create a scalar function definition of a function zName 
................................................................................
**     that accepts nArg arguments and is implemented by a call to C 
**     function likeFunc. Argument pArg is cast to a (void *) and made
**     available as the function user-data (sqlite3_user_data()). The
**     FuncDef.flags variable is set to the value passed as the flags
**     parameter.
*/
#define FUNCTION(zName, nArg, iArg, bNC, xFunc) \
  {nArg, SQLITE_UTF8, (bNC*SQLITE_FUNC_NEEDCOLL), \
   SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, #zName, 0, 0}
#define FUNCTION2(zName, nArg, iArg, bNC, xFunc, extraFlags) \
  {nArg, SQLITE_UTF8, (bNC*SQLITE_FUNC_NEEDCOLL)|extraFlags, \
   SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, #zName, 0, 0}
#define STR_FUNCTION(zName, nArg, pArg, bNC, xFunc) \
  {nArg, SQLITE_UTF8, bNC*SQLITE_FUNC_NEEDCOLL, \
   pArg, 0, xFunc, 0, 0, #zName, 0, 0}
#define LIKEFUNC(zName, nArg, arg, flags) \
  {nArg, SQLITE_UTF8, flags, (void *)arg, 0, likeFunc, 0, 0, #zName, 0, 0}
#define AGGREGATE(zName, nArg, arg, nc, xStep, xFinal) \
  {nArg, SQLITE_UTF8, nc*SQLITE_FUNC_NEEDCOLL, \
   SQLITE_INT_TO_PTR(arg), 0, 0, xStep,xFinal,#zName,0,0}

/*
** All current savepoints are stored in a linked list starting at
** sqlite3.pSavepoint. The first element in the list is the most recently
** opened savepoint. Savepoints are added to the list by the vdbe
** OP_Savepoint instruction.
................................................................................
  char *zName;     /* Name of this column */
  Expr *pDflt;     /* Default value of this column */
  char *zDflt;     /* Original text of the default value */
  char *zType;     /* Data type for this column */
  char *zColl;     /* Collating sequence.  If NULL, use the default */
  u8 notNull;      /* An OE_ code for handling a NOT NULL constraint */
  char affinity;   /* One of the SQLITE_AFF_... values */

  u16 colFlags;    /* Boolean properties.  See COLFLAG_ defines below */
};

/* Allowed values for Column.colFlags:
*/
#define COLFLAG_PRIMKEY  0x0001    /* Column is part of the primary key */
#define COLFLAG_HIDDEN   0x0002    /* A hidden column in a virtual table */

................................................................................
  ExprList *pCheck;    /* All CHECK constraints */
#endif
  tRowcnt nRowEst;     /* Estimated rows in table - from sqlite_stat1 table */
  int tnum;            /* Root BTree node for this table (see note above) */
  i16 iPKey;           /* If not negative, use aCol[iPKey] as the primary key */
  i16 nCol;            /* Number of columns in this table */
  u16 nRef;            /* Number of pointers to this Table */

  u8 tabFlags;         /* Mask of TF_* values */
  u8 keyConf;          /* What to do in case of uniqueness conflict on iPKey */
#ifndef SQLITE_OMIT_ALTERTABLE
  int addColOffset;    /* Offset in CREATE TABLE stmt to add a new column */
#endif
#ifndef SQLITE_OMIT_VIRTUALTABLE
  int nModuleArg;      /* Number of arguments to the module */
................................................................................
#define OE_Replace  5   /* Delete existing record, then do INSERT or UPDATE */

#define OE_Restrict 6   /* OE_Abort for IMMEDIATE, OE_Rollback for DEFERRED */
#define OE_SetNull  7   /* Set the foreign key value to NULL */
#define OE_SetDflt  8   /* Set the foreign key value to its default */
#define OE_Cascade  9   /* Cascade the changes */

#define OE_Default  99  /* Do whatever the default action is */


/*
** An instance of the following structure is passed as the first
** argument to sqlite3VdbeKeyCompare and is used to control the 
** comparison of the two index keys.
**
................................................................................
  char *zColAff;           /* String defining the affinity of each column */
  Index *pNext;            /* The next index associated with the same table */
  Schema *pSchema;         /* Schema containing this index */
  u8 *aSortOrder;          /* for each column: True==DESC, False==ASC */
  char **azColl;           /* Array of collation sequence names for index */
  Expr *pPartIdxWhere;     /* WHERE clause for partial indices */
  int tnum;                /* DB Page containing root of this index */

  u16 nColumn;             /* Number of columns in table used by this index */
  u8 onError;              /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
  unsigned autoIndex:2;    /* 1==UNIQUE, 2==PRIMARY KEY, 0==CREATE INDEX */
  unsigned bUnordered:1;   /* Use this index for == or IN queries only */
  unsigned uniqNotNull:1;  /* True if UNIQUE and NOT NULL for all columns */
#ifdef SQLITE_ENABLE_STAT3
  int nSample;             /* Number of elements in aSample[] */
  tRowcnt avgEq;           /* Average nEq value for key values not in aSample */

  IndexSample *aSample;    /* Samples of the left-most key */
#endif
};

/*
** Each sample stored in the sqlite_stat3 table is represented in memory 
** using a structure of this type.  See documentation at the top of the
** analyze.c source file for additional information.
*/
struct IndexSample {
  union {
    char *z;        /* Value if eType is SQLITE_TEXT or SQLITE_BLOB */
    double r;       /* Value if eType is SQLITE_FLOAT */
    i64 i;          /* Value if eType is SQLITE_INTEGER */
  } u;
  u8 eType;         /* SQLITE_NULL, SQLITE_INTEGER ... etc. */
  int nByte;        /* Size in byte of text or blob. */
  tRowcnt nEq;      /* Est. number of rows where the key equals this sample */
  tRowcnt nLt;      /* Est. number of rows where key is less than this sample */
  tRowcnt nDLt;     /* Est. number of distinct keys less than this sample */
};

/*
** Each token coming out of the lexer is an instance of
** this structure.  Tokens are also used as part of an expression.
**
** Note if Token.z==0 then Token.dyn and Token.n are undefined and
................................................................................
** are contained within the same memory allocation.  Note, however, that
** the subtrees in Expr.x.pList or Expr.x.pSelect are always separately
** allocated, regardless of whether or not EP_Reduced is set.
*/
struct Expr {
  u8 op;                 /* Operation performed by this node */
  char affinity;         /* The affinity of the column or 0 if not a column */
  u16 flags;             /* Various flags.  EP_* See below */
  union {
    char *zToken;          /* Token value. Zero terminated and dequoted */
    int iValue;            /* Non-negative integer value if EP_IntValue */
  } u;

  /* If the EP_TokenOnly flag is set in the Expr.flags mask, then no
  ** space is allocated for the fields below this point. An attempt to
  ** access them will result in a segfault or malfunction. 
  *********************************************************************/

  Expr *pLeft;           /* Left subnode */
  Expr *pRight;          /* Right subnode */
  union {
    ExprList *pList;     /* Function arguments or in "<expr> IN (<expr-list)" */
    Select *pSelect;     /* Used for sub-selects and "<expr> IN (<select>)" */
  } x;

  /* If the EP_Reduced flag is set in the Expr.flags mask, then no
  ** space is allocated for the fields below this point. An attempt to
  ** access them will result in a segfault or malfunction.
  *********************************************************************/

#if SQLITE_MAX_EXPR_DEPTH>0
  int nHeight;           /* Height of the tree headed by this node */
#endif
  int iTable;            /* TK_COLUMN: cursor number of table holding column
                         ** TK_REGISTER: register number
                         ** TK_TRIGGER: 1 -> new, 0 -> old */

  ynVar iColumn;         /* TK_COLUMN: column index.  -1 for rowid.
                         ** TK_VARIABLE: variable number (always >= 1). */
  i16 iAgg;              /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
  i16 iRightJoinTable;   /* If EP_FromJoin, the right table of the join */
  u8 flags2;             /* Second set of flags.  EP2_... */
  u8 op2;                /* TK_REGISTER: original value of Expr.op
                         ** TK_COLUMN: the value of p5 for OP_Column
                         ** TK_AGG_FUNCTION: nesting depth */
  AggInfo *pAggInfo;     /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */
  Table *pTab;           /* Table for TK_COLUMN expressions. */
};

/*
** The following are the meanings of bits in the Expr.flags field.
*/
#define EP_FromJoin   0x0001  /* Originated in ON or USING clause of a join */
#define EP_Agg        0x0002  /* Contains one or more aggregate functions */
#define EP_Resolved   0x0004  /* IDs have been resolved to COLUMNs */
#define EP_Error      0x0008  /* Expression contains one or more errors */
#define EP_Distinct   0x0010  /* Aggregate function with DISTINCT keyword */
#define EP_VarSelect  0x0020  /* pSelect is correlated, not constant */
#define EP_DblQuoted  0x0040  /* token.z was originally in "..." */
#define EP_InfixFunc  0x0080  /* True for an infix function: LIKE, GLOB, etc */
#define EP_Collate    0x0100  /* Tree contains a TK_COLLATE opeartor */
#define EP_FixedDest  0x0200  /* Result needed in a specific register */
#define EP_IntValue   0x0400  /* Integer value contained in u.iValue */
#define EP_xIsSelect  0x0800  /* x.pSelect is valid (otherwise x.pList is) */
#define EP_Hint       0x1000  /* Not used */
#define EP_Reduced    0x2000  /* Expr struct is EXPR_REDUCEDSIZE bytes only */
#define EP_TokenOnly  0x4000  /* Expr struct is EXPR_TOKENONLYSIZE bytes only */
#define EP_Static     0x8000  /* Held in memory not obtained from malloc() */

/*
** The following are the meanings of bits in the Expr.flags2 field.
*/
#define EP2_MallocedToken  0x0001  /* Need to sqlite3DbFree() Expr.zToken */
#define EP2_Irreducible    0x0002  /* Cannot EXPRDUP_REDUCE this Expr */

/*
** The pseudo-routine sqlite3ExprSetIrreducible sets the EP2_Irreducible
** flag on an expression structure.  This flag is used for VV&A only.  The
** routine is implemented as a macro that only works when in debugging mode,
** so as not to burden production code.
*/
#ifdef SQLITE_DEBUG
# define ExprSetIrreducible(X)  (X)->flags2 |= EP2_Irreducible
#else
# define ExprSetIrreducible(X)
#endif

/*
** These macros can be used to test, set, or clear bits in the 
** Expr.flags field.
*/
#define ExprHasProperty(E,P)     (((E)->flags&(P))==(P))
#define ExprHasAnyProperty(E,P)  (((E)->flags&(P))!=0)
#define ExprSetProperty(E,P)     (E)->flags|=(P)
#define ExprClearProperty(E,P)   (E)->flags&=~(P)

/*
** Macros to determine the number of bytes required by a normal Expr 
** struct, an Expr struct with the EP_Reduced flag set in Expr.flags 
** and an Expr struct with the EP_TokenOnly flag set.
*/
#define EXPR_FULLSIZE           sizeof(Expr)           /* Full size */
................................................................................
** routines as they walk the parse tree to make database references
** explicit.  
*/
typedef struct DbFixer DbFixer;
struct DbFixer {
  Parse *pParse;      /* The parsing context.  Error messages written here */
  Schema *pSchema;    /* Fix items to this schema */

  const char *zDb;    /* Make sure all objects are contained in this database */
  const char *zType;  /* Type of the container - used for error messages */
  const Token *pName; /* Name of the container - used for error messages */
};

/*
** An objected used to accumulate the text of a string where we
................................................................................
# define sqlite3AuthRead(a,b,c,d)
# define sqlite3AuthCheck(a,b,c,d,e)    SQLITE_OK
# define sqlite3AuthContextPush(a,b,c)
# define sqlite3AuthContextPop(a)  ((void)(a))
#endif
SQLITE_PRIVATE void sqlite3Attach(Parse*, Expr*, Expr*, Expr*);
SQLITE_PRIVATE void sqlite3Detach(Parse*, Expr*);
SQLITE_PRIVATE int sqlite3FixInit(DbFixer*, Parse*, int, const char*, const Token*);
SQLITE_PRIVATE int sqlite3FixSrcList(DbFixer*, SrcList*);
SQLITE_PRIVATE int sqlite3FixSelect(DbFixer*, Select*);
SQLITE_PRIVATE int sqlite3FixExpr(DbFixer*, Expr*);
SQLITE_PRIVATE int sqlite3FixExprList(DbFixer*, ExprList*);
SQLITE_PRIVATE int sqlite3FixTriggerStep(DbFixer*, TriggerStep*);
SQLITE_PRIVATE int sqlite3AtoF(const char *z, double*, int, u8);
SQLITE_PRIVATE int sqlite3GetInt32(const char *, int*);
SQLITE_PRIVATE int sqlite3Atoi(const char*);
SQLITE_PRIVATE int sqlite3Utf16ByteLen(const void *pData, int nChar);
SQLITE_PRIVATE int sqlite3Utf8CharLen(const char *pData, int nByte);
SQLITE_PRIVATE u32 sqlite3Utf8Read(const u8**);







/*
** Routines to read and write variable-length integers.  These used to
** be defined locally, but now we use the varint routines in the util.c
** file.  Code should use the MACRO forms below, as the Varint32 versions
** are coded to assume the single byte case is already handled (which 
** the MACRO form does).
................................................................................
SQLITE_PRIVATE const void *sqlite3ValueText(sqlite3_value*, u8);
SQLITE_PRIVATE int sqlite3ValueBytes(sqlite3_value*, u8);
SQLITE_PRIVATE void sqlite3ValueSetStr(sqlite3_value*, int, const void *,u8, 
                        void(*)(void*));
SQLITE_PRIVATE void sqlite3ValueFree(sqlite3_value*);
SQLITE_PRIVATE sqlite3_value *sqlite3ValueNew(sqlite3 *);
SQLITE_PRIVATE char *sqlite3Utf16to8(sqlite3 *, const void*, int, u8);
#ifdef SQLITE_ENABLE_STAT3
SQLITE_PRIVATE char *sqlite3Utf8to16(sqlite3 *, u8, char *, int, int *);
#endif
SQLITE_PRIVATE int sqlite3ValueFromExpr(sqlite3 *, Expr *, u8, u8, sqlite3_value **);
SQLITE_PRIVATE void sqlite3ValueApplyAffinity(sqlite3_value *, u8, u8);
#ifndef SQLITE_AMALGAMATION
SQLITE_PRIVATE const unsigned char sqlite3OpcodeProperty[];
SQLITE_PRIVATE const unsigned char sqlite3UpperToLower[];
SQLITE_PRIVATE const unsigned char sqlite3CtypeMap[];
SQLITE_PRIVATE const Token sqlite3IntTokens[];
................................................................................
SQLITE_PRIVATE void sqlite3ResolveSelectNames(Parse*, Select*, NameContext*);
SQLITE_PRIVATE void sqlite3ResolveSelfReference(Parse*,Table*,int,Expr*,ExprList*);
SQLITE_PRIVATE int sqlite3ResolveOrderGroupBy(Parse*, Select*, ExprList*, const char*);
SQLITE_PRIVATE void sqlite3ColumnDefault(Vdbe *, Table *, int, int);
SQLITE_PRIVATE void sqlite3AlterFinishAddColumn(Parse *, Token *);
SQLITE_PRIVATE void sqlite3AlterBeginAddColumn(Parse *, SrcList *);
SQLITE_PRIVATE CollSeq *sqlite3GetCollSeq(Parse*, u8, CollSeq *, const char*);
SQLITE_PRIVATE char sqlite3AffinityType(const char*);
SQLITE_PRIVATE void sqlite3Analyze(Parse*, Token*, Token*);
SQLITE_PRIVATE int sqlite3InvokeBusyHandler(BusyHandler*);
SQLITE_PRIVATE int sqlite3FindDb(sqlite3*, Token*);
SQLITE_PRIVATE int sqlite3FindDbName(sqlite3 *, const char *);
SQLITE_PRIVATE int sqlite3AnalysisLoad(sqlite3*,int iDB);
SQLITE_PRIVATE void sqlite3DeleteIndexSamples(sqlite3*,Index*);
SQLITE_PRIVATE void sqlite3DefaultRowEst(Index*);
................................................................................
SQLITE_PRIVATE char *sqlite3StrAccumFinish(StrAccum*);
SQLITE_PRIVATE void sqlite3StrAccumReset(StrAccum*);
SQLITE_PRIVATE void sqlite3SelectDestInit(SelectDest*,int,int);
SQLITE_PRIVATE Expr *sqlite3CreateColumnExpr(sqlite3 *, SrcList *, int, int);

SQLITE_PRIVATE void sqlite3BackupRestart(sqlite3_backup *);
SQLITE_PRIVATE void sqlite3BackupUpdate(sqlite3_backup *, Pgno, const u8 *);







/*
** The interface to the LEMON-generated parser
*/
SQLITE_PRIVATE void *sqlite3ParserAlloc(void*(*)(size_t));
SQLITE_PRIVATE void sqlite3ParserFree(void*, void(*)(void*));
SQLITE_PRIVATE void sqlite3Parser(void*, int, Token, Parse*);
................................................................................
SQLITE_PRIVATE void sqlite3VtabArgExtend(Parse*, Token*);
SQLITE_PRIVATE int sqlite3VtabCallCreate(sqlite3*, int, const char *, char **);
SQLITE_PRIVATE int sqlite3VtabCallConnect(Parse*, Table*);
SQLITE_PRIVATE int sqlite3VtabCallDestroy(sqlite3*, int, const char *);
SQLITE_PRIVATE int sqlite3VtabBegin(sqlite3 *, VTable *);
SQLITE_PRIVATE FuncDef *sqlite3VtabOverloadFunction(sqlite3 *,FuncDef*, int nArg, Expr*);
SQLITE_PRIVATE void sqlite3InvalidFunction(sqlite3_context*,int,sqlite3_value**);

SQLITE_PRIVATE int sqlite3VdbeParameterIndex(Vdbe*, const char*, int);
SQLITE_PRIVATE int sqlite3TransferBindings(sqlite3_stmt *, sqlite3_stmt *);
SQLITE_PRIVATE int sqlite3Reprepare(Vdbe*);
SQLITE_PRIVATE void sqlite3ExprListCheckLength(Parse*, ExprList*, const char*);
SQLITE_PRIVATE CollSeq *sqlite3BinaryCompareCollSeq(Parse *, Expr *, Expr *);
SQLITE_PRIVATE int sqlite3TempInMemory(const sqlite3*);
SQLITE_PRIVATE const char *sqlite3JournalModename(int);
................................................................................
** no-op macros if OMIT_FOREIGN_KEY is defined. In this case no foreign
** key functionality is available. If OMIT_TRIGGER is defined but
** OMIT_FOREIGN_KEY is not, only some of the functions are no-oped. In
** this case foreign keys are parsed, but no other functionality is 
** provided (enforcement of FK constraints requires the triggers sub-system).
*/
#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
SQLITE_PRIVATE   void sqlite3FkCheck(Parse*, Table*, int, int);
SQLITE_PRIVATE   void sqlite3FkDropTable(Parse*, SrcList *, Table*);
SQLITE_PRIVATE   void sqlite3FkActions(Parse*, Table*, ExprList*, int);
SQLITE_PRIVATE   int sqlite3FkRequired(Parse*, Table*, int*, int);
SQLITE_PRIVATE   u32 sqlite3FkOldmask(Parse*, Table*);
SQLITE_PRIVATE   FKey *sqlite3FkReferences(Table *);
#else
  #define sqlite3FkActions(a,b,c,d)
  #define sqlite3FkCheck(a,b,c,d)
  #define sqlite3FkDropTable(a,b,c)
  #define sqlite3FkOldmask(a,b)      0
  #define sqlite3FkRequired(a,b,c,d) 0
#endif
#ifndef SQLITE_OMIT_FOREIGN_KEY
SQLITE_PRIVATE   void sqlite3FkDelete(sqlite3 *, Table*);
SQLITE_PRIVATE   int sqlite3FkLocateIndex(Parse*,Table*,FKey*,Index**,int**);
#else
  #define sqlite3FkDelete(a,b)
  #define sqlite3FkLocateIndex(a,b,c,d,e)
................................................................................
#endif
#ifdef SQLITE_ENABLE_OVERSIZE_CELL_CHECK
  "ENABLE_OVERSIZE_CELL_CHECK",
#endif
#ifdef SQLITE_ENABLE_RTREE
  "ENABLE_RTREE",
#endif


#ifdef SQLITE_ENABLE_STAT3
  "ENABLE_STAT3",
#endif
#ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
  "ENABLE_UNLOCK_NOTIFY",
#endif
#ifdef SQLITE_ENABLE_UPDATE_DELETE_LIMIT
  "ENABLE_UPDATE_DELETE_LIMIT",
................................................................................
  yDbMask btreeMask;      /* Bitmask of db->aDb[] entries referenced */
  yDbMask lockMask;       /* Subset of btreeMask that requires a lock */
  int iStatement;         /* Statement number (or 0 if has not opened stmt) */
  u32 aCounter[5];        /* Counters used by sqlite3_stmt_status() */
#ifndef SQLITE_OMIT_TRACE
  i64 startTime;          /* Time when query started - used for profiling */
#endif

  i64 nFkConstraint;      /* Number of imm. FK constraints this VM */
  i64 nStmtDefCons;       /* Number of def. constraints when stmt started */
  i64 nStmtDefImmCons;    /* Number of def. imm constraints when stmt started */
  char *zSql;             /* Text of the SQL statement that generated this */
  void *pFree;            /* Free this when deleting the vdbe */
#ifdef SQLITE_DEBUG
  FILE *trace;            /* Write an execution trace here, if not NULL */
................................................................................

/*
** Set the time to the current time reported by the VFS.
**
** Return the number of errors.
*/
static int setDateTimeToCurrent(sqlite3_context *context, DateTime *p){
  sqlite3 *db = sqlite3_context_db_handle(context);
  if( sqlite3OsCurrentTimeInt64(db->pVfs, &p->iJD)==SQLITE_OK ){
    p->validJD = 1;
    return 0;
  }else{
    return 1;
  }
}

................................................................................
** The following routine implements the rough equivalent of localtime_r()
** using whatever operating-system specific localtime facility that
** is available.  This routine returns 0 on success and
** non-zero on any kind of error.
**
** If the sqlite3GlobalConfig.bLocaltimeFault variable is true then this
** routine will always fail.




*/
static int osLocaltime(time_t *t, struct tm *pTm){
  int rc;
#if (!defined(HAVE_LOCALTIME_R) || !HAVE_LOCALTIME_R) \
      && (!defined(HAVE_LOCALTIME_S) || !HAVE_LOCALTIME_S)
  struct tm *pX;
#if SQLITE_THREADSAFE>0
................................................................................

  /* Initialize the contents of sLocal to avoid a compiler warning. */
  memset(&sLocal, 0, sizeof(sLocal));

  x = *p;
  computeYMD_HMS(&x);
  if( x.Y<1971 || x.Y>=2038 ){





    x.Y = 2000;
    x.M = 1;
    x.D = 1;
    x.h = 0;
    x.m = 0;
    x.s = 0.0;
  } else {
................................................................................
  struct tm *pTm;
  struct tm sNow;
  char zBuf[20];

  UNUSED_PARAMETER(argc);
  UNUSED_PARAMETER(argv);

  db = sqlite3_context_db_handle(context);
  if( sqlite3OsCurrentTimeInt64(db->pVfs, &iT) ) return;
  t = iT/1000 - 10000*(sqlite3_int64)21086676;
#ifdef HAVE_GMTIME_R
  pTm = gmtime_r(&t, &sNow);
#else
  sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
  pTm = gmtime(&t);
  if( pTm ) memcpy(&sNow, pTm, sizeof(sNow));
................................................................................
*/
static int sqlite3MemSize(void *p){
  struct MemBlockHdr *pHdr;
  if( !p ){
    return 0;
  }
  pHdr = sqlite3MemsysGetHeader(p);
  return pHdr->iSize;
}

/*
** Initialize the memory allocation subsystem.
*/
static int sqlite3MemInit(void *NotUsed){
  UNUSED_PARAMETER(NotUsed);
................................................................................
** to clear the content of a freed allocation to unpredictable values.
*/
static void randomFill(char *pBuf, int nByte){
  unsigned int x, y, r;
  x = SQLITE_PTR_TO_INT(pBuf);
  y = nByte | 1;
  while( nByte >= 4 ){
    x = (x>>1) ^ (-(x&1) & 0xd0000001);
    y = y*1103515245 + 12345;
    r = x ^ y;
    *(int*)pBuf = r;
    pBuf += 4;
    nByte -= 4;
  }
  while( nByte-- > 0 ){
    x = (x>>1) ^ (-(x&1) & 0xd0000001);
    y = y*1103515245 + 12345;
    r = x ^ y;
    *(pBuf++) = r & 0xff;
  }
}

/*
................................................................................
    pHdr->pNext->pPrev = pHdr->pPrev;
  }else{
    assert( mem.pLast==pHdr );
    mem.pLast = pHdr->pPrev;
  }
  z = (char*)pBt;
  z -= pHdr->nTitle;
  adjustStats(pHdr->iSize, -1);
  randomFill(z, sizeof(void*)*pHdr->nBacktraceSlots + sizeof(*pHdr) +
                pHdr->iSize + sizeof(int) + pHdr->nTitle);
  free(z);
  sqlite3_mutex_leave(mem.mutex);  
}

/*
** Change the size of an existing memory allocation.
**
................................................................................
  struct MemBlockHdr *pOldHdr;
  void *pNew;
  assert( mem.disallow==0 );
  assert( (nByte & 7)==0 );     /* EV: R-46199-30249 */
  pOldHdr = sqlite3MemsysGetHeader(pPrior);
  pNew = sqlite3MemMalloc(nByte);
  if( pNew ){
    memcpy(pNew, pPrior, nByte<pOldHdr->iSize ? nByte : pOldHdr->iSize);
    if( nByte>pOldHdr->iSize ){
      randomFill(&((char*)pNew)[pOldHdr->iSize], nByte - pOldHdr->iSize);
    }
    sqlite3MemFree(pPrior);
  }
  return pNew;
}

/*
................................................................................
}

SQLITE_PRIVATE void sqlite3MemdebugSync(){
  struct MemBlockHdr *pHdr;
  for(pHdr=mem.pFirst; pHdr; pHdr=pHdr->pNext){
    void **pBt = (void**)pHdr;
    pBt -= pHdr->nBacktraceSlots;
    mem.xBacktrace(pHdr->iSize, pHdr->nBacktrace-1, &pBt[1]);
  }
}

/*
** Open the file indicated and write a log of all unfreed memory 
** allocations into that log.
*/
................................................................................
      OSVERSIONINFO sInfo;
      sInfo.dwOSVersionInfoSize = sizeof(sInfo);
      GetVersionEx(&sInfo);
      osType = sInfo.dwPlatformId==VER_PLATFORM_WIN32_NT ? 2 : 1;
    }
    return osType==2;
  }
#endif /* SQLITE_OS_WINCE */
#endif

#ifdef SQLITE_DEBUG
/*
** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routine are
** intended for use only inside assert() statements.
*/
................................................................................
};
static int winMutex_isInit = 0;
/* As winMutexInit() and winMutexEnd() are called as part
** of the sqlite3_initialize and sqlite3_shutdown()
** processing, the "interlocked" magic is probably not
** strictly necessary.
*/
static long winMutex_lock = 0;

SQLITE_API void sqlite3_win32_sleep(DWORD milliseconds); /* os_win.c */

static int winMutexInit(void){ 
  /* The first to increment to 1 does actual initialization */
  if( InterlockedCompareExchange(&winMutex_lock, 1, 0)==0 ){
    int i;
................................................................................

/*
** Free memory that might be associated with a particular database
** connection.
*/
SQLITE_PRIVATE void sqlite3DbFree(sqlite3 *db, void *p){
  assert( db==0 || sqlite3_mutex_held(db->mutex) );

  if( db ){
    if( db->pnBytesFreed ){
      *db->pnBytesFreed += sqlite3DbMallocSize(db, p);
      return;
    }
    if( isLookaside(db, p) ){
      LookasideSlot *pBuf = (LookasideSlot*)p;
................................................................................
  assert( (m.flags & MEM_Term)!=0 || db->mallocFailed );
  assert( (m.flags & MEM_Str)!=0 || db->mallocFailed );
  assert( (m.flags & MEM_Dyn)!=0 || db->mallocFailed );
  assert( m.z || db->mallocFailed );
  return m.z;
}

/*
** Convert a UTF-8 string to the UTF-16 encoding specified by parameter
** enc. A pointer to the new string is returned, and the value of *pnOut
** is set to the length of the returned string in bytes. The call should
** arrange to call sqlite3DbFree() on the returned pointer when it is
** no longer required.
** 
** If a malloc failure occurs, NULL is returned and the db.mallocFailed
** flag set.
*/
#ifdef SQLITE_ENABLE_STAT3
SQLITE_PRIVATE char *sqlite3Utf8to16(sqlite3 *db, u8 enc, char *z, int n, int *pnOut){
  Mem m;
  memset(&m, 0, sizeof(m));
  m.db = db;
  sqlite3VdbeMemSetStr(&m, z, n, SQLITE_UTF8, SQLITE_STATIC);
  if( sqlite3VdbeMemTranslate(&m, enc) ){
    assert( db->mallocFailed );
    return 0;
  }
  assert( m.z==m.zMalloc );
  *pnOut = m.n;
  return m.z;
}
#endif

/*
** zIn is a UTF-16 encoded unicode string at least nChar characters long.
** Return the number of bytes in the first nChar unicode characters
** in pZ.  nChar must be non-negative.
*/
SQLITE_PRIVATE int sqlite3Utf16ByteLen(const void *zIn, int nChar){
  int c;
................................................................................
  switch( quote ){
    case '\'':  break;
    case '"':   break;
    case '`':   break;                /* For MySQL compatibility */
    case '[':   quote = ']';  break;  /* For MS SqlServer compatibility */
    default:    return -1;
  }
  for(i=1, j=0; ALWAYS(z[i]); i++){

    if( z[i]==quote ){
      if( z[i+1]==quote ){
        z[j++] = quote;
        i++;
      }else{
        break;
      }
................................................................................
    int i, sz;
    sz = sqlite3Strlen30(z);
    for(i=sz-1; i>0 && z[i]!='/' && z[i]!='.'; i--){}
    if( z[i]=='.' && ALWAYS(sz>i+4) ) memmove(&z[i+1], &z[sz-3], 4);
  }
}
#endif














































































/************** End of util.c ************************************************/
/************** Begin file hash.c ********************************************/
/*
** 2001 September 22
**
** The author disclaims copyright to this source code.  In place of
................................................................................
  unsigned short int ctrlFlags;       /* Behavioral bits.  UNIXFILE_* flags */
  int lastErrno;                      /* The unix errno from last I/O error */
  void *lockingContext;               /* Locking style specific state */
  UnixUnusedFd *pUnused;              /* Pre-allocated UnixUnusedFd */
  const char *zPath;                  /* Name of the file */
  unixShm *pShm;                      /* Shared memory segment information */
  int szChunk;                        /* Configured by FCNTL_CHUNK_SIZE */

  int nFetchOut;                      /* Number of outstanding xFetch refs */
  sqlite3_int64 mmapSize;             /* Usable size of mapping at pMapRegion */
  sqlite3_int64 mmapSizeActual;       /* Actual size of mapping at pMapRegion */
  sqlite3_int64 mmapSizeMax;          /* Configured FCNTL_MMAP_SIZE value */
  void *pMapRegion;                   /* Memory mapped region */

#ifdef __QNXNTO__
  int sectorSize;                     /* Device sector size */
  int deviceCharacteristics;          /* Precomputed device characteristics */
#endif
#if SQLITE_ENABLE_LOCKING_STYLE
  int openFlags;                      /* The flags specified at open() */
#endif
................................................................................

  { "rmdir",        (sqlite3_syscall_ptr)rmdir,           0 },
#define osRmdir     ((int(*)(const char*))aSyscall[19].pCurrent)

  { "fchown",       (sqlite3_syscall_ptr)posixFchown,     0 },
#define osFchown    ((int(*)(int,uid_t,gid_t))aSyscall[20].pCurrent)


  { "mmap",       (sqlite3_syscall_ptr)mmap,     0 },
#define osMmap ((void*(*)(void*,size_t,int,int,int,off_t))aSyscall[21].pCurrent)

  { "munmap",       (sqlite3_syscall_ptr)munmap,          0 },
#define osMunmap ((void*(*)(void*,size_t))aSyscall[22].pCurrent)

#if HAVE_MREMAP
  { "mremap",       (sqlite3_syscall_ptr)mremap,          0 },
#else
  { "mremap",       (sqlite3_syscall_ptr)0,               0 },
#endif
#define osMremap ((void*(*)(void*,size_t,size_t,int,...))aSyscall[23].pCurrent)


}; /* End of the overrideable system calls */

/*
** This is the xSetSystemCall() method of sqlite3_vfs for all of the
** "unix" VFSes.  Return SQLITE_OK opon successfully updating the
** system call pointer, or SQLITE_NOTFOUND if there is no configurable
................................................................................
  }
  for(i++; i<ArraySize(aSyscall); i++){
    if( aSyscall[i].pCurrent!=0 ) return aSyscall[i].zName;
  }
  return 0;
}










/*
** Invoke open().  Do so multiple times, until it either succeeds or
** fails for some reason other than EINTR.
**
** If the file creation mode "m" is 0 then set it to the default for
** SQLite.  The default is SQLITE_DEFAULT_FILE_PERMISSIONS (normally
** 0644) as modified by the system umask.  If m is not 0, then
................................................................................
** transaction crashes and leaves behind hot journals, then any
** process that is able to write to the database will also be able to
** recover the hot journals.
*/
static int robust_open(const char *z, int f, mode_t m){
  int fd;
  mode_t m2 = m ? m : SQLITE_DEFAULT_FILE_PERMISSIONS;
  do{
#if defined(O_CLOEXEC)
    fd = osOpen(z,f|O_CLOEXEC,m2);
#else
    fd = osOpen(z,f,m2);
#endif

  }while( fd<0 && errno==EINTR );









  if( fd>=0 ){
    if( m!=0 ){
      struct stat statbuf;
      if( osFstat(fd, &statbuf)==0 
       && statbuf.st_size==0
       && (statbuf.st_mode&0777)!=m 
      ){
................................................................................
** the requested locking level, this routine is a no-op.
*/
static int unixUnlock(sqlite3_file *id, int eFileLock){
  assert( eFileLock==SHARED_LOCK || ((unixFile *)id)->nFetchOut==0 );
  return posixUnlock(id, eFileLock, 0);
}


static int unixMapfile(unixFile *pFd, i64 nByte);
static void unixUnmapfile(unixFile *pFd);


/*
** This function performs the parts of the "close file" operation 
** common to all locking schemes. It closes the directory and file
** handles, if they are valid, and sets all fields of the unixFile
** structure to 0.
**
** It is *not* necessary to hold the mutex when this routine is called,
** even on VxWorks.  A mutex will be acquired on VxWorks by the
** vxworksReleaseFileId() routine.
*/
static int closeUnixFile(sqlite3_file *id){
  unixFile *pFile = (unixFile*)id;

  unixUnmapfile(pFile);

  if( pFile->h>=0 ){
    robust_close(pFile, pFile->h, __LINE__);
    pFile->h = -1;
  }
#if OS_VXWORKS
  if( pFile->pId ){
    if( pFile->ctrlFlags & UNIXFILE_DELETE ){
................................................................................
  int got;
  int prior = 0;
#if (!defined(USE_PREAD) && !defined(USE_PREAD64))
  i64 newOffset;
#endif
  TIMER_START;
  assert( cnt==(cnt&0x1ffff) );

  cnt &= 0x1ffff;
  do{
#if defined(USE_PREAD)
    got = osPread(id->h, pBuf, cnt, offset);
    SimulateIOError( got = -1 );
#elif defined(USE_PREAD64)
    got = osPread64(id->h, pBuf, cnt, offset);
................................................................................
  const void *pBuf,               /* Copy data from this buffer to the file */
  int nBuf,                       /* Size of buffer pBuf in bytes */
  int *piErrno                    /* OUT: Error number if error occurs */
){
  int rc = 0;                     /* Value returned by system call */

  assert( nBuf==(nBuf&0x1ffff) );

  nBuf &= 0x1ffff;
  TIMER_START;

#if defined(USE_PREAD)
  do{ rc = osPwrite(fd, pBuf, nBuf, iOff); }while( rc<0 && errno==EINTR );
#elif defined(USE_PREAD64)
  do{ rc = osPwrite64(fd, pBuf, nBuf, iOff);}while( rc<0 && errno==EINTR);
................................................................................
    ** source.
    */
    if( pFile->inNormalWrite && nByte==0 ){
      pFile->transCntrChng = 1;
    }
#endif


    /* If the file was just truncated to a size smaller than the currently
    ** mapped region, reduce the effective mapping size as well. SQLite will
    ** use read() and write() to access data beyond this point from now on.  
    */
    if( nByte<pFile->mmapSize ){
      pFile->mmapSize = nByte;
    }


    return SQLITE_OK;
  }
}

/*
** Determine the current size of a file in bytes
................................................................................
        if( nWrite!=1 ) return SQLITE_IOERR_WRITE;
        iWrite += nBlk;
      }
#endif
    }
  }


  if( pFile->mmapSizeMax>0 && nByte>pFile->mmapSize ){
    int rc;
    if( pFile->szChunk<=0 ){
      if( robust_ftruncate(pFile->h, nByte) ){
        pFile->lastErrno = errno;
        return unixLogError(SQLITE_IOERR_TRUNCATE, "ftruncate", pFile->zPath);
      }
    }

    rc = unixMapfile(pFile, nByte);
    return rc;
  }


  return SQLITE_OK;
}

/*
** If *pArg is inititially negative then this is a query.  Set *pArg to
** 1 or 0 depending on whether or not bit mask of pFile->ctrlFlags is set.
................................................................................
      char *zTFile = sqlite3_malloc( pFile->pVfs->mxPathname );
      if( zTFile ){
        unixGetTempname(pFile->pVfs->mxPathname, zTFile);
        *(char**)pArg = zTFile;
      }
      return SQLITE_OK;
    }

    case SQLITE_FCNTL_MMAP_SIZE: {
      i64 newLimit = *(i64*)pArg;
      int rc = SQLITE_OK;
      if( newLimit>sqlite3GlobalConfig.mxMmap ){
        newLimit = sqlite3GlobalConfig.mxMmap;
      }
      *(i64*)pArg = pFile->mmapSizeMax;
................................................................................
        if( pFile->mmapSize>0 ){
          unixUnmapfile(pFile);
          rc = unixMapfile(pFile, -1);
        }
      }
      return rc;
    }

#ifdef SQLITE_DEBUG
    /* The pager calls this method to signal that it has done
    ** a rollback and that the database is therefore unchanged and
    ** it hence it is OK for the transaction change counter to be
    ** unchanged.
    */
    case SQLITE_FCNTL_DB_UNCHANGED: {
................................................................................
#else
# define unixShmMap     0
# define unixShmLock    0
# define unixShmBarrier 0
# define unixShmUnmap   0
#endif /* #ifndef SQLITE_OMIT_WAL */


/*
** If it is currently memory mapped, unmap file pFd.
*/
static void unixUnmapfile(unixFile *pFd){
  assert( pFd->nFetchOut==0 );
#if SQLITE_MAX_MMAP_SIZE>0
  if( pFd->pMapRegion ){
    osMunmap(pFd->pMapRegion, pFd->mmapSizeActual);
    pFd->pMapRegion = 0;
    pFd->mmapSize = 0;
    pFd->mmapSizeActual = 0;
  }
#endif
}

#if SQLITE_MAX_MMAP_SIZE>0
/*
** Return the system page size.
*/
static int unixGetPagesize(void){
#if HAVE_MREMAP
  return 512;
#elif defined(_BSD_SOURCE)
  return getpagesize();
#else
  return (int)sysconf(_SC_PAGESIZE);
#endif
}
#endif /* SQLITE_MAX_MMAP_SIZE>0 */

#if SQLITE_MAX_MMAP_SIZE>0
/*
** Attempt to set the size of the memory mapping maintained by file 
** descriptor pFd to nNew bytes. Any existing mapping is discarded.
**
** If successful, this function sets the following variables:
**
**       unixFile.pMapRegion
................................................................................
    ** will probably fail too. Fall back to using xRead/xWrite exclusively
    ** in this case.  */
    pFd->mmapSizeMax = 0;
  }
  pFd->pMapRegion = (void *)pNew;
  pFd->mmapSize = pFd->mmapSizeActual = nNew;
}
#endif

/*
** Memory map or remap the file opened by file-descriptor pFd (if the file
** is already mapped, the existing mapping is replaced by the new). Or, if 
** there already exists a mapping for this file, and there are still 
** outstanding xFetch() references to it, this function is a no-op.
**
................................................................................
** using SQLITE_FCNTL_MMAP_LIMIT, whichever is smaller.
**
** SQLITE_OK is returned if no error occurs (even if the mapping is not
** recreated as a result of outstanding references) or an SQLite error
** code otherwise.
*/
static int unixMapfile(unixFile *pFd, i64 nByte){
#if SQLITE_MAX_MMAP_SIZE>0
  i64 nMap = nByte;
  int rc;

  assert( nMap>=0 || pFd->nFetchOut==0 );
  if( pFd->nFetchOut>0 ) return SQLITE_OK;

  if( nMap<0 ){
................................................................................
  if( nMap!=pFd->mmapSize ){
    if( nMap>0 ){
      unixRemapfile(pFd, nMap);
    }else{
      unixUnmapfile(pFd);
    }
  }
#endif

  return SQLITE_OK;
}


/*
** If possible, return a pointer to a mapping of file fd starting at offset
** iOff. The mapping must be valid for at least nAmt bytes.
**
** If such a pointer can be obtained, store it in *pp and return SQLITE_OK.
** Or, if one cannot but no error occurs, set *pp to 0 and return SQLITE_OK.
................................................................................
** to inform the VFS layer that, according to POSIX, any existing mapping 
** may now be invalid and should be unmapped.
*/
static int unixUnfetch(sqlite3_file *fd, i64 iOff, void *p){
  unixFile *pFd = (unixFile *)fd;   /* The underlying database file */
  UNUSED_PARAMETER(iOff);


  /* If p==0 (unmap the entire file) then there must be no outstanding 
  ** xFetch references. Or, if p!=0 (meaning it is an xFetch reference),
  ** then there must be at least one outstanding.  */
  assert( (p==0)==(pFd->nFetchOut==0) );

  /* If p!=0, it must match the iOff value. */
  assert( p==0 || p==&((u8 *)pFd->pMapRegion)[iOff] );
................................................................................
  if( p ){
    pFd->nFetchOut--;
  }else{
    unixUnmapfile(pFd);
  }

  assert( pFd->nFetchOut>=0 );

  return SQLITE_OK;
}

/*
** Here ends the implementation of all sqlite3_file methods.
**
********************** End sqlite3_file Methods *******************************
................................................................................
  assert( zFilename!=0 || (ctrlFlags & UNIXFILE_NOLOCK)!=0 );

  OSTRACE(("OPEN    %-3d %s\n", h, zFilename));
  pNew->h = h;
  pNew->pVfs = pVfs;
  pNew->zPath = zFilename;
  pNew->ctrlFlags = (u8)ctrlFlags;

  pNew->mmapSizeMax = sqlite3GlobalConfig.szMmap;

  if( sqlite3_uri_boolean(((ctrlFlags & UNIXFILE_URI) ? zFilename : 0),
                           "psow", SQLITE_POWERSAFE_OVERWRITE) ){
    pNew->ctrlFlags |= UNIXFILE_PSOW;
  }
  if( strcmp(pVfs->zName,"unix-excl")==0 ){
    pNew->ctrlFlags |= UNIXFILE_EXCL;
  }
................................................................................
/*
** Return the name of a directory in which to put temporary files.
** If no suitable temporary file directory can be found, return NULL.
*/
static const char *unixTempFileDir(void){
  static const char *azDirs[] = {
     0,

     0,
     "/var/tmp",
     "/usr/tmp",
     "/tmp",
     0        /* List terminator */
  };
  unsigned int i;
  struct stat buf;
  const char *zDir = 0;

  azDirs[0] = sqlite3_temp_directory;
  if( !azDirs[1] ) azDirs[1] = getenv("TMPDIR");

  for(i=0; i<sizeof(azDirs)/sizeof(azDirs[0]); zDir=azDirs[i++]){
    if( zDir==0 ) continue;
    if( osStat(zDir, &buf) ) continue;
    if( !S_ISDIR(buf.st_mode) ) continue;
    if( osAccess(zDir, 07) ) continue;
    break;
  }
................................................................................
**
** This file contains code that is specific to Windows.
*/
#if SQLITE_OS_WIN               /* This file is used for Windows only */

#ifdef __CYGWIN__
# include <sys/cygwin.h>
/* # include <errno.h> */
#endif

/*
** Include code that is common to all os_*.c files
*/
/************** Include os_common.h in the middle of os_win.c ****************/
/************** Begin file os_common.h ***************************************/
................................................................................
/************** Continuing where we left off in os_win.c *********************/

/*
** Compiling and using WAL mode requires several APIs that are only
** available in Windows platforms based on the NT kernel.
*/
#if !SQLITE_OS_WINNT && !defined(SQLITE_OMIT_WAL)
# error "WAL mode requires support from the Windows NT kernel, compile\
 with SQLITE_OMIT_WAL."
#endif

/*
** Are most of the Win32 ANSI APIs available (i.e. with certain exceptions
** based on the sub-platform)?
*/
#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
#  define SQLITE_WIN32_HAS_ANSI
#endif

/*
** Are most of the Win32 Unicode APIs available (i.e. with certain exceptions
** based on the sub-platform)?
*/
#if SQLITE_OS_WINCE || SQLITE_OS_WINNT || SQLITE_OS_WINRT

#  define SQLITE_WIN32_HAS_WIDE
#endif













































































/*
** Do we need to manually define the Win32 file mapping APIs for use with WAL
** mode (e.g. these APIs are available in the Windows CE SDK; however, they
** are not present in the header file)?
*/
#if SQLITE_WIN32_FILEMAPPING_API && !defined(SQLITE_OMIT_WAL)
/*
................................................................................
#endif

#ifndef FILE_ATTRIBUTE_MASK
# define FILE_ATTRIBUTE_MASK     (0x0003FFF7)
#endif

#ifndef SQLITE_OMIT_WAL
/* Forward references */
typedef struct winShm winShm;           /* A connection to shared-memory */
typedef struct winShmNode winShmNode;   /* A region of shared-memory */
#endif

/*
** WinCE lacks native support for file locking so we have to fake it
** with some code of our own.
................................................................................
** 2:   Operating system is WinNT.
**
** In order to facilitate testing on a WinNT system, the test fixture
** can manually set this value to 1 to emulate Win98 behavior.
*/
#ifdef SQLITE_TEST
SQLITE_API int sqlite3_os_type = 0;
#else

static int sqlite3_os_type = 0;
#endif

#ifndef SYSCALL
#  define SYSCALL sqlite3_syscall_ptr
#endif

................................................................................
  { "GetVersionExA",           (SYSCALL)GetVersionExA,           0 },
#else
  { "GetVersionExA",           (SYSCALL)0,                       0 },
#endif

#define osGetVersionExA ((BOOL(WINAPI*)( \
        LPOSVERSIONINFOA))aSyscall[34].pCurrent)










  { "HeapAlloc",               (SYSCALL)HeapAlloc,               0 },

#define osHeapAlloc ((LPVOID(WINAPI*)(HANDLE,DWORD, \
        SIZE_T))aSyscall[35].pCurrent)

#if !SQLITE_OS_WINRT
  { "HeapCreate",              (SYSCALL)HeapCreate,              0 },
#else
  { "HeapCreate",              (SYSCALL)0,                       0 },
#endif

#define osHeapCreate ((HANDLE(WINAPI*)(DWORD,SIZE_T, \
        SIZE_T))aSyscall[36].pCurrent)

#if !SQLITE_OS_WINRT
  { "HeapDestroy",             (SYSCALL)HeapDestroy,             0 },
#else
  { "HeapDestroy",             (SYSCALL)0,                       0 },
#endif

#define osHeapDestroy ((BOOL(WINAPI*)(HANDLE))aSyscall[37].pCurrent)

  { "HeapFree",                (SYSCALL)HeapFree,                0 },

#define osHeapFree ((BOOL(WINAPI*)(HANDLE,DWORD,LPVOID))aSyscall[38].pCurrent)

  { "HeapReAlloc",             (SYSCALL)HeapReAlloc,             0 },

#define osHeapReAlloc ((LPVOID(WINAPI*)(HANDLE,DWORD,LPVOID, \
        SIZE_T))aSyscall[39].pCurrent)

  { "HeapSize",                (SYSCALL)HeapSize,                0 },

#define osHeapSize ((SIZE_T(WINAPI*)(HANDLE,DWORD, \
        LPCVOID))aSyscall[40].pCurrent)

#if !SQLITE_OS_WINRT
  { "HeapValidate",            (SYSCALL)HeapValidate,            0 },
#else
  { "HeapValidate",            (SYSCALL)0,                       0 },
#endif

#define osHeapValidate ((BOOL(WINAPI*)(HANDLE,DWORD, \
        LPCVOID))aSyscall[41].pCurrent)

#if defined(SQLITE_WIN32_HAS_ANSI) && !defined(SQLITE_OMIT_LOAD_EXTENSION)
  { "LoadLibraryA",            (SYSCALL)LoadLibraryA,            0 },
#else
  { "LoadLibraryA",            (SYSCALL)0,                       0 },
#endif

#define osLoadLibraryA ((HMODULE(WINAPI*)(LPCSTR))aSyscall[42].pCurrent)

#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE) && \
        !defined(SQLITE_OMIT_LOAD_EXTENSION)
  { "LoadLibraryW",            (SYSCALL)LoadLibraryW,            0 },
#else
  { "LoadLibraryW",            (SYSCALL)0,                       0 },
#endif

#define osLoadLibraryW ((HMODULE(WINAPI*)(LPCWSTR))aSyscall[43].pCurrent)

#if !SQLITE_OS_WINRT
  { "LocalFree",               (SYSCALL)LocalFree,               0 },
#else
  { "LocalFree",               (SYSCALL)0,                       0 },
#endif

#define osLocalFree ((HLOCAL(WINAPI*)(HLOCAL))aSyscall[44].pCurrent)

#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
  { "LockFile",                (SYSCALL)LockFile,                0 },
#else
  { "LockFile",                (SYSCALL)0,                       0 },
#endif

#ifndef osLockFile
#define osLockFile ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
        DWORD))aSyscall[45].pCurrent)
#endif

#if !SQLITE_OS_WINCE
  { "LockFileEx",              (SYSCALL)LockFileEx,              0 },
#else
  { "LockFileEx",              (SYSCALL)0,                       0 },
#endif

#ifndef osLockFileEx
#define osLockFileEx ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD,DWORD, \
        LPOVERLAPPED))aSyscall[46].pCurrent)
#endif

#if SQLITE_OS_WINCE || (!SQLITE_OS_WINRT && !defined(SQLITE_OMIT_WAL))
  { "MapViewOfFile",           (SYSCALL)MapViewOfFile,           0 },
#else
  { "MapViewOfFile",           (SYSCALL)0,                       0 },
#endif

#define osMapViewOfFile ((LPVOID(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
        SIZE_T))aSyscall[47].pCurrent)

  { "MultiByteToWideChar",     (SYSCALL)MultiByteToWideChar,     0 },

#define osMultiByteToWideChar ((int(WINAPI*)(UINT,DWORD,LPCSTR,int,LPWSTR, \
        int))aSyscall[48].pCurrent)

  { "QueryPerformanceCounter", (SYSCALL)QueryPerformanceCounter, 0 },

#define osQueryPerformanceCounter ((BOOL(WINAPI*)( \
        LARGE_INTEGER*))aSyscall[49].pCurrent)

  { "ReadFile",                (SYSCALL)ReadFile,                0 },

#define osReadFile ((BOOL(WINAPI*)(HANDLE,LPVOID,DWORD,LPDWORD, \
        LPOVERLAPPED))aSyscall[50].pCurrent)

  { "SetEndOfFile",            (SYSCALL)SetEndOfFile,            0 },

#define osSetEndOfFile ((BOOL(WINAPI*)(HANDLE))aSyscall[51].pCurrent)

#if !SQLITE_OS_WINRT
  { "SetFilePointer",          (SYSCALL)SetFilePointer,          0 },
#else
  { "SetFilePointer",          (SYSCALL)0,                       0 },
#endif

#define osSetFilePointer ((DWORD(WINAPI*)(HANDLE,LONG,PLONG, \
        DWORD))aSyscall[52].pCurrent)

#if !SQLITE_OS_WINRT
  { "Sleep",                   (SYSCALL)Sleep,                   0 },
#else
  { "Sleep",                   (SYSCALL)0,                       0 },
#endif

#define osSleep ((VOID(WINAPI*)(DWORD))aSyscall[53].pCurrent)

  { "SystemTimeToFileTime",    (SYSCALL)SystemTimeToFileTime,    0 },

#define osSystemTimeToFileTime ((BOOL(WINAPI*)(CONST SYSTEMTIME*, \
        LPFILETIME))aSyscall[54].pCurrent)

#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
  { "UnlockFile",              (SYSCALL)UnlockFile,              0 },
#else
  { "UnlockFile",              (SYSCALL)0,                       0 },
#endif

#ifndef osUnlockFile
#define osUnlockFile ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
        DWORD))aSyscall[55].pCurrent)
#endif

#if !SQLITE_OS_WINCE
  { "UnlockFileEx",            (SYSCALL)UnlockFileEx,            0 },
#else
  { "UnlockFileEx",            (SYSCALL)0,                       0 },
#endif

#define osUnlockFileEx ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
        LPOVERLAPPED))aSyscall[56].pCurrent)

#if SQLITE_OS_WINCE || !defined(SQLITE_OMIT_WAL)
  { "UnmapViewOfFile",         (SYSCALL)UnmapViewOfFile,         0 },
#else
  { "UnmapViewOfFile",         (SYSCALL)0,                       0 },
#endif

#define osUnmapViewOfFile ((BOOL(WINAPI*)(LPCVOID))aSyscall[57].pCurrent)

  { "WideCharToMultiByte",     (SYSCALL)WideCharToMultiByte,     0 },

#define osWideCharToMultiByte ((int(WINAPI*)(UINT,DWORD,LPCWSTR,int,LPSTR,int, \
        LPCSTR,LPBOOL))aSyscall[58].pCurrent)

  { "WriteFile",               (SYSCALL)WriteFile,               0 },

#define osWriteFile ((BOOL(WINAPI*)(HANDLE,LPCVOID,DWORD,LPDWORD, \
        LPOVERLAPPED))aSyscall[59].pCurrent)

#if SQLITE_OS_WINRT
  { "CreateEventExW",          (SYSCALL)CreateEventExW,          0 },
#else
  { "CreateEventExW",          (SYSCALL)0,                       0 },
#endif

#define osCreateEventExW ((HANDLE(WINAPI*)(LPSECURITY_ATTRIBUTES,LPCWSTR, \
        DWORD,DWORD))aSyscall[60].pCurrent)

#if !SQLITE_OS_WINRT
  { "WaitForSingleObject",     (SYSCALL)WaitForSingleObject,     0 },
#else
  { "WaitForSingleObject",     (SYSCALL)0,                       0 },
#endif

#define osWaitForSingleObject ((DWORD(WINAPI*)(HANDLE, \
        DWORD))aSyscall[61].pCurrent)

#if SQLITE_OS_WINRT
  { "WaitForSingleObjectEx",   (SYSCALL)WaitForSingleObjectEx,   0 },
#else
  { "WaitForSingleObjectEx",   (SYSCALL)0,                       0 },
#endif

#define osWaitForSingleObjectEx ((DWORD(WINAPI*)(HANDLE,DWORD, \
        BOOL))aSyscall[62].pCurrent)

#if SQLITE_OS_WINRT
  { "SetFilePointerEx",        (SYSCALL)SetFilePointerEx,        0 },
#else
  { "SetFilePointerEx",        (SYSCALL)0,                       0 },
#endif

#define osSetFilePointerEx ((BOOL(WINAPI*)(HANDLE,LARGE_INTEGER, \
        PLARGE_INTEGER,DWORD))aSyscall[63].pCurrent)

#if SQLITE_OS_WINRT
  { "GetFileInformationByHandleEx", (SYSCALL)GetFileInformationByHandleEx, 0 },
#else
  { "GetFileInformationByHandleEx", (SYSCALL)0,                  0 },
#endif

#define osGetFileInformationByHandleEx ((BOOL(WINAPI*)(HANDLE, \
        FILE_INFO_BY_HANDLE_CLASS,LPVOID,DWORD))aSyscall[64].pCurrent)

#if SQLITE_OS_WINRT && !defined(SQLITE_OMIT_WAL)
  { "MapViewOfFileFromApp",    (SYSCALL)MapViewOfFileFromApp,    0 },
#else
  { "MapViewOfFileFromApp",    (SYSCALL)0,                       0 },
#endif

#define osMapViewOfFileFromApp ((LPVOID(WINAPI*)(HANDLE,ULONG,ULONG64, \
        SIZE_T))aSyscall[65].pCurrent)

#if SQLITE_OS_WINRT
  { "CreateFile2",             (SYSCALL)CreateFile2,             0 },
#else
  { "CreateFile2",             (SYSCALL)0,                       0 },
#endif

#define osCreateFile2 ((HANDLE(WINAPI*)(LPCWSTR,DWORD,DWORD,DWORD, \
        LPCREATEFILE2_EXTENDED_PARAMETERS))aSyscall[66].pCurrent)

#if SQLITE_OS_WINRT && !defined(SQLITE_OMIT_LOAD_EXTENSION)
  { "LoadPackagedLibrary",     (SYSCALL)LoadPackagedLibrary,     0 },
#else
  { "LoadPackagedLibrary",     (SYSCALL)0,                       0 },
#endif

#define osLoadPackagedLibrary ((HMODULE(WINAPI*)(LPCWSTR, \
        DWORD))aSyscall[67].pCurrent)

#if SQLITE_OS_WINRT
  { "GetTickCount64",          (SYSCALL)GetTickCount64,          0 },
#else
  { "GetTickCount64",          (SYSCALL)0,                       0 },
#endif

#define osGetTickCount64 ((ULONGLONG(WINAPI*)(VOID))aSyscall[68].pCurrent)

#if SQLITE_OS_WINRT
  { "GetNativeSystemInfo",     (SYSCALL)GetNativeSystemInfo,     0 },
#else
  { "GetNativeSystemInfo",     (SYSCALL)0,                       0 },
#endif

#define osGetNativeSystemInfo ((VOID(WINAPI*)( \
        LPSYSTEM_INFO))aSyscall[69].pCurrent)

#if defined(SQLITE_WIN32_HAS_ANSI)
  { "OutputDebugStringA",      (SYSCALL)OutputDebugStringA,      0 },
#else
  { "OutputDebugStringA",      (SYSCALL)0,                       0 },
#endif

#define osOutputDebugStringA ((VOID(WINAPI*)(LPCSTR))aSyscall[70].pCurrent)

#if defined(SQLITE_WIN32_HAS_WIDE)
  { "OutputDebugStringW",      (SYSCALL)OutputDebugStringW,      0 },
#else
  { "OutputDebugStringW",      (SYSCALL)0,                       0 },
#endif

#define osOutputDebugStringW ((VOID(WINAPI*)(LPCWSTR))aSyscall[71].pCurrent)

  { "GetProcessHeap",          (SYSCALL)GetProcessHeap,          0 },

#define osGetProcessHeap ((HANDLE(WINAPI*)(VOID))aSyscall[72].pCurrent)

#if SQLITE_OS_WINRT && !defined(SQLITE_OMIT_WAL)
  { "CreateFileMappingFromApp", (SYSCALL)CreateFileMappingFromApp, 0 },
#else
  { "CreateFileMappingFromApp", (SYSCALL)0,                      0 },
#endif

#define osCreateFileMappingFromApp ((HANDLE(WINAPI*)(HANDLE, \
        LPSECURITY_ATTRIBUTES,ULONG,ULONG64,LPCWSTR))aSyscall[73].pCurrent)

}; /* End of the overrideable system calls */

/*
** This is the xSetSystemCall() method of sqlite3_vfs for all of the
** "win32" VFSes.  Return SQLITE_OK opon successfully updating the
** system call pointer, or SQLITE_NOTFOUND if there is no configurable
................................................................................
** Here is an interesting observation:  Win95, Win98, and WinME lack
** the LockFileEx() API.  But we can still statically link against that
** API as long as we don't call it when running Win95/98/ME.  A call to
** this routine is used to determine if the host is Win95/98/ME or
** WinNT/2K/XP so that we will know whether or not we can safely call
** the LockFileEx() API.
*/




#if SQLITE_OS_WINCE || SQLITE_OS_WINRT
# define isNT()  (1)
#elif !defined(SQLITE_WIN32_HAS_WIDE)
# define isNT()  (0)
#else
  static int isNT(void){
    if( sqlite3_os_type==0 ){





      OSVERSIONINFOA sInfo;
      sInfo.dwOSVersionInfoSize = sizeof(sInfo);
      osGetVersionExA(&sInfo);

      sqlite3_os_type = sInfo.dwPlatformId==VER_PLATFORM_WIN32_NT ? 2 : 1;
    }
    return sqlite3_os_type==2;
  }
#endif

#ifdef SQLITE_WIN32_MALLOC
................................................................................
  assert( hHeap!=INVALID_HANDLE_VALUE );
#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
  assert ( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
#endif
  assert( nBytes>=0 );
  p = osHeapAlloc(hHeap, SQLITE_WIN32_HEAP_FLAGS, (SIZE_T)nBytes);
  if( !p ){
    sqlite3_log(SQLITE_NOMEM, "failed to HeapAlloc %u bytes (%d), heap=%p",
                nBytes, osGetLastError(), (void*)hHeap);
  }
  return p;
}

/*
** Free memory.
................................................................................
  assert( hHeap!=0 );
  assert( hHeap!=INVALID_HANDLE_VALUE );
#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
  assert ( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior) );
#endif
  if( !pPrior ) return; /* Passing NULL to HeapFree is undefined. */
  if( !osHeapFree(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior) ){
    sqlite3_log(SQLITE_NOMEM, "failed to HeapFree block %p (%d), heap=%p",
                pPrior, osGetLastError(), (void*)hHeap);
  }
}

/*
** Change the size of an existing memory allocation
*/
................................................................................
  assert( nBytes>=0 );
  if( !pPrior ){
    p = osHeapAlloc(hHeap, SQLITE_WIN32_HEAP_FLAGS, (SIZE_T)nBytes);
  }else{
    p = osHeapReAlloc(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior, (SIZE_T)nBytes);
  }
  if( !p ){
    sqlite3_log(SQLITE_NOMEM, "failed to %s %u bytes (%d), heap=%p",
                pPrior ? "HeapReAlloc" : "HeapAlloc", nBytes, osGetLastError(),
                (void*)hHeap);
  }
  return p;
}

/*
................................................................................
  assert( hHeap!=INVALID_HANDLE_VALUE );
#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
  assert ( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
#endif
  if( !p ) return 0;
  n = osHeapSize(hHeap, SQLITE_WIN32_HEAP_FLAGS, p);
  if( n==(SIZE_T)-1 ){
    sqlite3_log(SQLITE_NOMEM, "failed to HeapSize block %p (%d), heap=%p",
                p, osGetLastError(), (void*)hHeap);
    return 0;
  }
  return (int)n;
}

/*
................................................................................
#if !SQLITE_OS_WINRT && SQLITE_WIN32_HEAP_CREATE
  if( !pWinMemData->hHeap ){
    pWinMemData->hHeap = osHeapCreate(SQLITE_WIN32_HEAP_FLAGS,
                                      SQLITE_WIN32_HEAP_INIT_SIZE,
                                      SQLITE_WIN32_HEAP_MAX_SIZE);
    if( !pWinMemData->hHeap ){
      sqlite3_log(SQLITE_NOMEM,
          "failed to HeapCreate (%d), flags=%u, initSize=%u, maxSize=%u",
          osGetLastError(), SQLITE_WIN32_HEAP_FLAGS,
          SQLITE_WIN32_HEAP_INIT_SIZE, SQLITE_WIN32_HEAP_MAX_SIZE);
      return SQLITE_NOMEM;
    }
    pWinMemData->bOwned = TRUE;
    assert( pWinMemData->bOwned );
  }
#else
  pWinMemData->hHeap = osGetProcessHeap();
  if( !pWinMemData->hHeap ){
    sqlite3_log(SQLITE_NOMEM,
        "failed to GetProcessHeap (%d)", osGetLastError());
    return SQLITE_NOMEM;
  }
  pWinMemData->bOwned = FALSE;
  assert( !pWinMemData->bOwned );
#endif
  assert( pWinMemData->hHeap!=0 );
  assert( pWinMemData->hHeap!=INVALID_HANDLE_VALUE );
................................................................................
  if( pWinMemData->hHeap ){
    assert( pWinMemData->hHeap!=INVALID_HANDLE_VALUE );
#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
    assert( osHeapValidate(pWinMemData->hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
#endif
    if( pWinMemData->bOwned ){
      if( !osHeapDestroy(pWinMemData->hHeap) ){
        sqlite3_log(SQLITE_NOMEM, "failed to HeapDestroy (%d), heap=%p",
                    osGetLastError(), (void*)pWinMemData->hHeap);
      }
      pWinMemData->bOwned = FALSE;
    }
    pWinMemData->hHeap = NULL;
  }
}
................................................................................
#endif /* SQLITE_WIN32_MALLOC */

/*
** Convert a UTF-8 string to Microsoft Unicode (UTF-16?). 
**
** Space to hold the returned string is obtained from malloc.
*/
static LPWSTR utf8ToUnicode(const char *zFilename){
  int nChar;
  LPWSTR zWideFilename;

  nChar = osMultiByteToWideChar(CP_UTF8, 0, zFilename, -1, NULL, 0);
  if( nChar==0 ){
    return 0;
  }
................................................................................
  return zWideFilename;
}

/*
** Convert Microsoft Unicode to UTF-8.  Space to hold the returned string is
** obtained from sqlite3_malloc().
*/
static char *unicodeToUtf8(LPCWSTR zWideFilename){
  int nByte;
  char *zFilename;

  nByte = osWideCharToMultiByte(CP_UTF8, 0, zWideFilename, -1, 0, 0, 0, 0);
  if( nByte == 0 ){
    return 0;
  }
................................................................................
/*
** Convert an ANSI string to Microsoft Unicode, based on the
** current codepage settings for file apis.
** 
** Space to hold the returned string is obtained
** from sqlite3_malloc.
*/
static LPWSTR mbcsToUnicode(const char *zFilename){
  int nByte;
  LPWSTR zMbcsFilename;
  int codepage = osAreFileApisANSI() ? CP_ACP : CP_OEMCP;

  nByte = osMultiByteToWideChar(codepage, 0, zFilename, -1, NULL,
                                0)*sizeof(WCHAR);
  if( nByte==0 ){
................................................................................
/*
** Convert Microsoft Unicode to multi-byte character string, based on the
** user's ANSI codepage.
**
** Space to hold the returned string is obtained from
** sqlite3_malloc().
*/
static char *unicodeToMbcs(LPCWSTR zWideFilename){
  int nByte;
  char *zFilename;
  int codepage = osAreFileApisANSI() ? CP_ACP : CP_OEMCP;

  nByte = osWideCharToMultiByte(codepage, 0, zWideFilename, -1, 0, 0, 0, 0);
  if( nByte == 0 ){
    return 0;
................................................................................
** Convert multibyte character string to UTF-8.  Space to hold the
** returned string is obtained from sqlite3_malloc().
*/
SQLITE_API char *sqlite3_win32_mbcs_to_utf8(const char *zFilename){
  char *zFilenameUtf8;
  LPWSTR zTmpWide;

  zTmpWide = mbcsToUnicode(zFilename);
  if( zTmpWide==0 ){
    return 0;
  }
  zFilenameUtf8 = unicodeToUtf8(zTmpWide);
  sqlite3_free(zTmpWide);
  return zFilenameUtf8;
}

/*
** Convert UTF-8 to multibyte character string.  Space to hold the 
** returned string is obtained from sqlite3_malloc().
*/
SQLITE_API char *sqlite3_win32_utf8_to_mbcs(const char *zFilename){
  char *zFilenameMbcs;
  LPWSTR zTmpWide;

  zTmpWide = utf8ToUnicode(zFilename);
  if( zTmpWide==0 ){
    return 0;
  }
  zFilenameMbcs = unicodeToMbcs(zTmpWide);
  sqlite3_free(zTmpWide);
  return zFilenameMbcs;
}

/*
** This function sets the data directory or the temporary directory based on
** the provided arguments.  The type argument must be 1 in order to set the
................................................................................
  assert( !ppDirectory || type==SQLITE_WIN32_DATA_DIRECTORY_TYPE
          || type==SQLITE_WIN32_TEMP_DIRECTORY_TYPE
  );
  assert( !ppDirectory || sqlite3MemdebugHasType(*ppDirectory, MEMTYPE_HEAP) );
  if( ppDirectory ){
    char *zValueUtf8 = 0;
    if( zValue && zValue[0] ){
      zValueUtf8 = unicodeToUtf8(zValue);
      if ( zValueUtf8==0 ){
        return SQLITE_NOMEM;
      }
    }
    sqlite3_free(*ppDirectory);
    *ppDirectory = zValueUtf8;
    return SQLITE_OK;
  }
  return SQLITE_ERROR;
}

/*
** The return value of getLastErrorMsg
** is zero if the error message fits in the buffer, or non-zero
** otherwise (if the message was truncated).
*/
static int getLastErrorMsg(DWORD lastErrno, int nBuf, char *zBuf){
  /* FormatMessage returns 0 on failure.  Otherwise it
  ** returns the number of TCHARs written to the output
  ** buffer, excluding the terminating null char.
  */
  DWORD dwLen = 0;
  char *zOut = 0;

  if( isNT() ){
#if SQLITE_OS_WINRT
    WCHAR zTempWide[MAX_PATH+1]; /* NOTE: Somewhat arbitrary. */
    dwLen = osFormatMessageW(FORMAT_MESSAGE_FROM_SYSTEM |
                             FORMAT_MESSAGE_IGNORE_INSERTS,
                             NULL,
                             lastErrno,
                             0,
                             zTempWide,
                             MAX_PATH,
                             0);
#else
    LPWSTR zTempWide = NULL;
    dwLen = osFormatMessageW(FORMAT_MESSAGE_ALLOCATE_BUFFER |
                             FORMAT_MESSAGE_FROM_SYSTEM |
                             FORMAT_MESSAGE_IGNORE_INSERTS,
                             NULL,
................................................................................
                             (LPWSTR) &zTempWide,
                             0,
                             0);
#endif
    if( dwLen > 0 ){
      /* allocate a buffer and convert to UTF8 */
      sqlite3BeginBenignMalloc();
      zOut = unicodeToUtf8(zTempWide);
      sqlite3EndBenignMalloc();
#if !SQLITE_OS_WINRT
      /* free the system buffer allocated by FormatMessage */
      osLocalFree(zTempWide);
#endif
    }
  }
................................................................................
  const char *zPath,              /* File path associated with error */
  int iLine                       /* Source line number where error occurred */
){
  char zMsg[500];                 /* Human readable error text */
  int i;                          /* Loop counter */

  zMsg[0] = 0;
  getLastErrorMsg(lastErrno, sizeof(zMsg), zMsg);
  assert( errcode!=SQLITE_OK );
  if( zPath==0 ) zPath = "";
  for(i=0; zMsg[i] && zMsg[i]!='\r' && zMsg[i]!='\n'; i++){}
  zMsg[i] = 0;
  sqlite3_log(errcode,
      "os_win.c:%d: (%lu) %s(%s) - %s",
      iLine, lastErrno, zFunc, zPath, zMsg
................................................................................
*/
#ifndef SQLITE_WIN32_IOERR_RETRY
# define SQLITE_WIN32_IOERR_RETRY 10
#endif
#ifndef SQLITE_WIN32_IOERR_RETRY_DELAY
# define SQLITE_WIN32_IOERR_RETRY_DELAY 25
#endif
static int win32IoerrRetry = SQLITE_WIN32_IOERR_RETRY;
static int win32IoerrRetryDelay = SQLITE_WIN32_IOERR_RETRY_DELAY;

/*
** If a ReadFile() or WriteFile() error occurs, invoke this routine
** to see if it should be retried.  Return TRUE to retry.  Return FALSE
** to give up with an error.
*/
static int retryIoerr(int *pnRetry, DWORD *pError){
  DWORD e = osGetLastError();
  if( *pnRetry>=win32IoerrRetry ){
    if( pError ){
      *pError = e;
    }
    return 0;
  }
  if( e==ERROR_ACCESS_DENIED ||
      e==ERROR_LOCK_VIOLATION ||
      e==ERROR_SHARING_VIOLATION ){
    sqlite3_win32_sleep(win32IoerrRetryDelay*(1+*pnRetry));
    ++*pnRetry;
    return 1;
  }
  if( pError ){
    *pError = e;
  }
  return 0;
}

/*
** Log a I/O error retry episode.
*/
static void logIoerr(int nRetry){
  if( nRetry ){
    sqlite3_log(SQLITE_IOERR, 
      "delayed %dms for lock/sharing conflict",
      win32IoerrRetryDelay*nRetry*(nRetry+1)/2
    );
  }
}

#if SQLITE_OS_WINCE
/*************************************************************************
** This section contains code for WinCE only.
................................................................................
static int winceCreateLock(const char *zFilename, winFile *pFile){
  LPWSTR zTok;
  LPWSTR zName;
  DWORD lastErrno;
  BOOL bLogged = FALSE;
  BOOL bInit = TRUE;

  zName = utf8ToUnicode(zFilename);
  if( zName==0 ){
    /* out of memory */
    return SQLITE_IOERR_NOMEM;
  }

  /* Initialize the local lockdata */
  memset(&pFile->local, 0, sizeof(pFile->local));
................................................................................
    if (*zTok == '\\') *zTok = '_';
  }

  /* Create/open the named mutex */
  pFile->hMutex = osCreateMutexW(NULL, FALSE, zName);
  if (!pFile->hMutex){
    pFile->lastErrno = osGetLastError();

    winLogError(SQLITE_IOERR, pFile->lastErrno,
                "winceCreateLock1", zFilename);
    sqlite3_free(zName);
    return SQLITE_IOERR;
  }

  /* Acquire the mutex before continuing */
  winceMutexAcquire(pFile->hMutex);
  
  /* Since the names of named mutexes, semaphores, file mappings etc are 
  ** case-sensitive, take advantage of that by uppercasing the mutex name
................................................................................
  /*
  ** NOTE: Windows CE is handled differently here due its lack of the Win32
  **       API LockFile.
  */
  return winceLockFile(phFile, offsetLow, offsetHigh,
                       numBytesLow, numBytesHigh);
#else
  if( isNT() ){
    OVERLAPPED ovlp;
    memset(&ovlp, 0, sizeof(OVERLAPPED));
    ovlp.Offset = offsetLow;
    ovlp.OffsetHigh = offsetHigh;
    return osLockFileEx(*phFile, flags, 0, numBytesLow, numBytesHigh, &ovlp);
  }else{
    return osLockFile(*phFile, offsetLow, offsetHigh, numBytesLow,
................................................................................
  /*
  ** NOTE: Windows CE is handled differently here due its lack of the Win32
  **       API UnlockFile.
  */
  return winceUnlockFile(phFile, offsetLow, offsetHigh,
                         numBytesLow, numBytesHigh);
#else
  if( isNT() ){
    OVERLAPPED ovlp;
    memset(&ovlp, 0, sizeof(OVERLAPPED));
    ovlp.Offset = offsetLow;
    ovlp.OffsetHigh = offsetHigh;
    return osUnlockFileEx(*phFile, 0, numBytesLow, numBytesHigh, &ovlp);
  }else{
    return osUnlockFile(*phFile, offsetLow, offsetHigh, numBytesLow,
................................................................................
#endif

/*
** Move the current position of the file handle passed as the first 
** argument to offset iOffset within the file. If successful, return 0. 
** Otherwise, set pFile->lastErrno and return non-zero.
*/
static int seekWinFile(winFile *pFile, sqlite3_int64 iOffset){
#if !SQLITE_OS_WINRT
  LONG upperBits;                 /* Most sig. 32 bits of new offset */
  LONG lowerBits;                 /* Least sig. 32 bits of new offset */
  DWORD dwRet;                    /* Value returned by SetFilePointer() */
  DWORD lastErrno;                /* Value returned by GetLastError() */

  OSTRACE(("SEEK file=%p, offset=%lld\n", pFile->h, iOffset));
................................................................................
  */
  dwRet = osSetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);

  if( (dwRet==INVALID_SET_FILE_POINTER
      && ((lastErrno = osGetLastError())!=NO_ERROR)) ){
    pFile->lastErrno = lastErrno;
    winLogError(SQLITE_IOERR_SEEK, pFile->lastErrno,
             "seekWinFile", pFile->zPath);
    OSTRACE(("SEEK file=%p, rc=SQLITE_IOERR_SEEK\n", pFile->h));
    return 1;
  }

  OSTRACE(("SEEK file=%p, rc=SQLITE_OK\n", pFile->h));
  return 0;
#else
................................................................................

  x.QuadPart = iOffset;
  bRet = osSetFilePointerEx(pFile->h, x, 0, FILE_BEGIN);

  if(!bRet){
    pFile->lastErrno = osGetLastError();
    winLogError(SQLITE_IOERR_SEEK, pFile->lastErrno,
             "seekWinFile", pFile->zPath);
    OSTRACE(("SEEK file=%p, rc=SQLITE_IOERR_SEEK\n", pFile->h));
    return 1;
  }

  OSTRACE(("SEEK file=%p, rc=SQLITE_OK\n", pFile->h));
  return 0;
#endif
}

#if SQLITE_MAX_MMAP_SIZE>0
/* Forward references to VFS methods */

static int winUnmapfile(winFile*);
#endif

/*
** Close a file.
**
** It is reported that an attempt to close a handle might sometimes
................................................................................
      amt -= nCopy;
      offset += nCopy;
    }
  }
#endif

#if SQLITE_OS_WINCE
  if( seekWinFile(pFile, offset) ){
    OSTRACE(("READ file=%p, rc=SQLITE_FULL\n", pFile->h));
    return SQLITE_FULL;
  }
  while( !osReadFile(pFile->h, pBuf, amt, &nRead, 0) ){
#else
  memset(&overlapped, 0, sizeof(OVERLAPPED));
  overlapped.Offset = (LONG)(offset & 0xffffffff);
  overlapped.OffsetHigh = (LONG)((offset>>32) & 0x7fffffff);
  while( !osReadFile(pFile->h, pBuf, amt, &nRead, &overlapped) &&
         osGetLastError()!=ERROR_HANDLE_EOF ){
#endif
    DWORD lastErrno;
    if( retryIoerr(&nRetry, &lastErrno) ) continue;
    pFile->lastErrno = lastErrno;
    OSTRACE(("READ file=%p, rc=SQLITE_IOERR_READ\n", pFile->h));
    return winLogError(SQLITE_IOERR_READ, pFile->lastErrno,
             "winRead", pFile->zPath);
  }
  logIoerr(nRetry);
  if( nRead<(DWORD)amt ){
    /* Unread parts of the buffer must be zero-filled */
    memset(&((char*)pBuf)[nRead], 0, amt-nRead);
    OSTRACE(("READ file=%p, rc=SQLITE_IOERR_SHORT_READ\n", pFile->h));
    return SQLITE_IOERR_SHORT_READ;
  }

................................................................................
      amt -= nCopy;
      offset += nCopy;
    }
  }
#endif

#if SQLITE_OS_WINCE
  rc = seekWinFile(pFile, offset);
  if( rc==0 ){
#else
  {
#endif
#if !SQLITE_OS_WINCE
    OVERLAPPED overlapped;        /* The offset for WriteFile. */
#endif
................................................................................

    while( nRem>0 ){
#if SQLITE_OS_WINCE
      if( !osWriteFile(pFile->h, aRem, nRem, &nWrite, 0) ){
#else
      if( !osWriteFile(pFile->h, aRem, nRem, &nWrite, &overlapped) ){
#endif
        if( retryIoerr(&nRetry, &lastErrno) ) continue;
        break;
      }
      assert( nWrite==0 || nWrite<=(DWORD)nRem );
      if( nWrite==0 || nWrite>(DWORD)nRem ){
        lastErrno = osGetLastError();
        break;
      }
................................................................................
    }
  }

  if( rc ){
    if(   ( pFile->lastErrno==ERROR_HANDLE_DISK_FULL )
       || ( pFile->lastErrno==ERROR_DISK_FULL )){
      OSTRACE(("WRITE file=%p, rc=SQLITE_FULL\n", pFile->h));
      return SQLITE_FULL;

    }
    OSTRACE(("WRITE file=%p, rc=SQLITE_IOERR_WRITE\n", pFile->h));
    return winLogError(SQLITE_IOERR_WRITE, pFile->lastErrno,
             "winWrite", pFile->zPath);
  }else{
    logIoerr(nRetry);
  }
  OSTRACE(("WRITE file=%p, rc=SQLITE_OK\n", pFile->h));
  return SQLITE_OK;
}

/*
** Truncate an open file to a specified size
................................................................................
  ** size).
  */
  if( pFile->szChunk>0 ){
    nByte = ((nByte + pFile->szChunk - 1)/pFile->szChunk) * pFile->szChunk;
  }

  /* SetEndOfFile() returns non-zero when successful, or zero when it fails. */
  if( seekWinFile(pFile, nByte) ){
    rc = winLogError(SQLITE_IOERR_TRUNCATE, pFile->lastErrno,
                     "winTruncate1", pFile->zPath);
  }else if( 0==osSetEndOfFile(pFile->h) &&
            ((lastErrno = osGetLastError())!=ERROR_USER_MAPPED_FILE) ){
    pFile->lastErrno = lastErrno;
    rc = winLogError(SQLITE_IOERR_TRUNCATE, pFile->lastErrno,
                     "winTruncate2", pFile->zPath);
................................................................................
  sqlite3_sync_count++;
#endif

  /* If we compiled with the SQLITE_NO_SYNC flag, then syncing is a
  ** no-op
  */
#ifdef SQLITE_NO_SYNC

  return SQLITE_OK;
#else
  rc = osFlushFileBuffers(pFile->h);
  SimulateIOError( rc=FALSE );
  if( rc ){
    OSTRACE(("SYNC file=%p, rc=SQLITE_OK\n", pFile->h));
    return SQLITE_OK;
  }else{
    pFile->lastErrno = osGetLastError();
    OSTRACE(("SYNC file=%p, rc=SQLITE_IOERR_FSYNC\n", pFile->h));
    return winLogError(SQLITE_IOERR_FSYNC, pFile->lastErrno,
             "winSync", pFile->zPath);
  }
#endif
}

/*
** Determine the current size of a file in bytes
*/
................................................................................

    lowerBits = osGetFileSize(pFile->h, &upperBits);
    *pSize = (((sqlite3_int64)upperBits)<<32) + lowerBits;
    if(   (lowerBits == INVALID_FILE_SIZE)
       && ((lastErrno = osGetLastError())!=NO_ERROR) ){
      pFile->lastErrno = lastErrno;
      rc = winLogError(SQLITE_IOERR_FSTAT, pFile->lastErrno,
             "winFileSize", pFile->zPath);
    }
  }
#endif
  OSTRACE(("SIZE file=%p, pSize=%p, *pSize=%lld, rc=%s\n",
           pFile->h, pSize, *pSize, sqlite3ErrName(rc)));
  return rc;
}
................................................................................
#endif

/*
** Acquire a reader lock.
** Different API routines are called depending on whether or not this
** is Win9x or WinNT.
*/
static int getReadLock(winFile *pFile){
  int res;
  OSTRACE(("READ-LOCK file=%p, lock=%d\n", pFile->h, pFile->locktype));
  if( isNT() ){
#if SQLITE_OS_WINCE
    /*
    ** NOTE: Windows CE is handled differently here due its lack of the Win32
    **       API LockFileEx.
    */
    res = winceLockFile(&pFile->h, SHARED_FIRST, 0, 1, 0);
#else
................................................................................
  OSTRACE(("READ-LOCK file=%p, rc=%s\n", pFile->h, sqlite3ErrName(res)));
  return res;
}

/*
** Undo a readlock
*/
static int unlockReadLock(winFile *pFile){
  int res;
  DWORD lastErrno;
  OSTRACE(("READ-UNLOCK file=%p, lock=%d\n", pFile->h, pFile->locktype));
  if( isNT() ){
    res = winUnlockFile(&pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
  }
#ifdef SQLITE_WIN32_HAS_ANSI
  else{
    res = winUnlockFile(&pFile->h, SHARED_FIRST+pFile->sharedLockByte, 0, 1, 0);
  }
#endif
  if( res==0 && ((lastErrno = osGetLastError())!=ERROR_NOT_LOCKED) ){
    pFile->lastErrno = lastErrno;
    winLogError(SQLITE_IOERR_UNLOCK, pFile->lastErrno,
             "unlockReadLock", pFile->zPath);
  }
  OSTRACE(("READ-UNLOCK file=%p, rc=%s\n", pFile->h, sqlite3ErrName(res)));
  return res;
}

/*
** Lock the file with the lock specified by parameter locktype - one
................................................................................
    }
  }

  /* Acquire a shared lock
  */
  if( locktype==SHARED_LOCK && res ){
    assert( pFile->locktype==NO_LOCK );
    res = getReadLock(pFile);
    if( res ){
      newLocktype = SHARED_LOCK;
    }else{
      lastErrno = osGetLastError();
    }
  }

................................................................................
    gotPendingLock = 0;
  }

  /* Acquire an EXCLUSIVE lock
  */
  if( locktype==EXCLUSIVE_LOCK && res ){
    assert( pFile->locktype>=SHARED_LOCK );
    res = unlockReadLock(pFile);
    res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS, SHARED_FIRST, 0,
                      SHARED_SIZE, 0);
    if( res ){
      newLocktype = EXCLUSIVE_LOCK;
    }else{
      lastErrno = osGetLastError();
      getReadLock(pFile);
    }
  }

  /* If we are holding a PENDING lock that ought to be released, then
  ** release it now.
  */
  if( gotPendingLock && locktype==SHARED_LOCK ){
................................................................................

  /* Update the state of the lock has held in the file descriptor then
  ** return the appropriate result code.
  */
  if( res ){
    rc = SQLITE_OK;
  }else{
    OSTRACE(("LOCK-FAIL file=%p, wanted=%d, got=%d\n",
             pFile->h, locktype, newLocktype));
    pFile->lastErrno = lastErrno;
    rc = SQLITE_BUSY;


  }
  pFile->locktype = (u8)newLocktype;
  OSTRACE(("LOCK file=%p, lock=%d, rc=%s\n",
           pFile->h, pFile->locktype, sqlite3ErrName(rc)));
  return rc;
}

................................................................................
  assert( pFile!=0 );
  assert( locktype<=SHARED_LOCK );
  OSTRACE(("UNLOCK file=%p, oldLock=%d(%d), newLock=%d\n",
           pFile->h, pFile->locktype, pFile->sharedLockByte, locktype));
  type = pFile->locktype;
  if( type>=EXCLUSIVE_LOCK ){
    winUnlockFile(&pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
    if( locktype==SHARED_LOCK && !getReadLock(pFile) ){
      /* This should never happen.  We should always be able to
      ** reacquire the read lock */
      rc = winLogError(SQLITE_IOERR_UNLOCK, osGetLastError(),
               "winUnlock", pFile->zPath);
    }
  }
  if( type>=RESERVED_LOCK ){
    winUnlockFile(&pFile->h, RESERVED_BYTE, 0, 1, 0);
  }
  if( locktype==NO_LOCK && type>=SHARED_LOCK ){
    unlockReadLock(pFile);
  }
  if( type>=PENDING_LOCK ){
    winUnlockFile(&pFile->h, PENDING_BYTE, 0, 1, 0);
  }
  pFile->locktype = (u8)locktype;
  OSTRACE(("UNLOCK file=%p, lock=%d, rc=%s\n",
           pFile->h, pFile->locktype, sqlite3ErrName(rc)));
................................................................................
  }else if( (*pArg)==0 ){
    pFile->ctrlFlags &= ~mask;
  }else{
    pFile->ctrlFlags |= mask;
  }
}

/* Forward declaration */
static int getTempname(int nBuf, char *zBuf);
#if SQLITE_MAX_MMAP_SIZE>0
static int winMapfile(winFile*, sqlite3_int64);
#endif

/*
** Control and query of the open file handle.
*/
static int winFileControl(sqlite3_file *id, int op, void *pArg){
  winFile *pFile = (winFile*)id;
  OSTRACE(("FCNTL file=%p, op=%d, pArg=%p\n", pFile->h, op, pArg));
................................................................................
      *(char**)pArg = sqlite3_mprintf("win32");
      OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
      return SQLITE_OK;
    }
    case SQLITE_FCNTL_WIN32_AV_RETRY: {
      int *a = (int*)pArg;
      if( a[0]>0 ){
        win32IoerrRetry = a[0];
      }else{
        a[0] = win32IoerrRetry;
      }
      if( a[1]>0 ){
        win32IoerrRetryDelay = a[1];
      }else{
        a[1] = win32IoerrRetryDelay;
      }
      OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
      return SQLITE_OK;
    }
    case SQLITE_FCNTL_TEMPFILENAME: {
      char *zTFile = sqlite3MallocZero( pFile->pVfs->mxPathname );
      if( zTFile ){
        getTempname(pFile->pVfs->mxPathname, zTFile);

        *(char**)pArg = zTFile;
      }
      OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
      return SQLITE_OK;
    }
#if SQLITE_MAX_MMAP_SIZE>0
    case SQLITE_FCNTL_MMAP_SIZE: {
      i64 newLimit = *(i64*)pArg;
      int rc = SQLITE_OK;
      if( newLimit>sqlite3GlobalConfig.mxMmap ){
        newLimit = sqlite3GlobalConfig.mxMmap;
................................................................................
      if( newLimit>=0 && newLimit!=pFile->mmapSizeMax && pFile->nFetchOut==0 ){
        pFile->mmapSizeMax = newLimit;
        if( pFile->mmapSize>0 ){
          (void)winUnmapfile(pFile);
          rc = winMapfile(pFile, -1);
        }
      }
      OSTRACE(("FCNTL file=%p, rc=%d\n", pFile->h, rc));
      return rc;
    }
#endif
  }
  OSTRACE(("FCNTL file=%p, rc=SQLITE_NOTFOUND\n", pFile->h));
  return SQLITE_NOTFOUND;
}
................................................................................
**
** This is not a VFS shared-memory method; it is a utility function called
** by VFS shared-memory methods.
*/
static void winShmPurge(sqlite3_vfs *pVfs, int deleteFlag){
  winShmNode **pp;
  winShmNode *p;
  BOOL bRc;
  assert( winShmMutexHeld() );
  OSTRACE(("SHM-PURGE pid=%lu, deleteFlag=%d\n",
           osGetCurrentProcessId(), deleteFlag));
  pp = &winShmNodeList;
  while( (p = *pp)!=0 ){
    if( p->nRef==0 ){
      int i;
      if( p->mutex ) sqlite3_mutex_free(p->mutex);
      for(i=0; i<p->nRegion; i++){
        bRc = osUnmapViewOfFile(p->aRegion[i].pMap);
        OSTRACE(("SHM-PURGE-UNMAP pid=%lu, region=%d, rc=%s\n",
                 osGetCurrentProcessId(), i, bRc ? "ok" : "failed"));

        bRc = osCloseHandle(p->aRegion[i].hMap);
        OSTRACE(("SHM-PURGE-CLOSE pid=%lu, region=%d, rc=%s\n",
                 osGetCurrentProcessId(), i, bRc ? "ok" : "failed"));

      }
      if( p->hFile.h!=NULL && p->hFile.h!=INVALID_HANDLE_VALUE ){
        SimulateIOErrorBenign(1);
        winClose((sqlite3_file *)&p->hFile);
        SimulateIOErrorBenign(0);
      }
      if( deleteFlag ){
................................................................................
    /* Check to see if another process is holding the dead-man switch.
    ** If not, truncate the file to zero length. 
    */
    if( winShmSystemLock(pShmNode, _SHM_WRLCK, WIN_SHM_DMS, 1)==SQLITE_OK ){
      rc = winTruncate((sqlite3_file *)&pShmNode->hFile, 0);
      if( rc!=SQLITE_OK ){
        rc = winLogError(SQLITE_IOERR_SHMOPEN, osGetLastError(),
                 "winOpenShm", pDbFd->zPath);
      }
    }
    if( rc==SQLITE_OK ){
      winShmSystemLock(pShmNode, _SHM_UNLCK, WIN_SHM_DMS, 1);
      rc = winShmSystemLock(pShmNode, _SHM_RDLCK, WIN_SHM_DMS, 1);
    }
    if( rc ) goto shm_open_err;
................................................................................
    /* The requested region is not mapped into this processes address space.
    ** Check to see if it has been allocated (i.e. if the wal-index file is
    ** large enough to contain the requested region).
    */
    rc = winFileSize((sqlite3_file *)&pShmNode->hFile, &sz);
    if( rc!=SQLITE_OK ){
      rc = winLogError(SQLITE_IOERR_SHMSIZE, osGetLastError(),
               "winShmMap1", pDbFd->zPath);
      goto shmpage_out;
    }

    if( sz<nByte ){
      /* The requested memory region does not exist. If isWrite is set to
      ** zero, exit early. *pp will be set to NULL and SQLITE_OK returned.
      **
................................................................................
      ** Alternatively, if isWrite is non-zero, use ftruncate() to allocate
      ** the requested memory region.
      */
      if( !isWrite ) goto shmpage_out;
      rc = winTruncate((sqlite3_file *)&pShmNode->hFile, nByte);
      if( rc!=SQLITE_OK ){
        rc = winLogError(SQLITE_IOERR_SHMSIZE, osGetLastError(),
                 "winShmMap2", pDbFd->zPath);
        goto shmpage_out;
      }
    }

    /* Map the requested memory region into this processes address space. */
    apNew = (struct ShmRegion *)sqlite3_realloc(
        pShmNode->aRegion, (iRegion+1)*sizeof(apNew[0])
................................................................................
        OSTRACE(("SHM-MAP-MAP pid=%lu, region=%d, offset=%d, size=%d, rc=%s\n",
                 osGetCurrentProcessId(), pShmNode->nRegion, iOffset,
                 szRegion, pMap ? "ok" : "failed"));
      }
      if( !pMap ){
        pShmNode->lastErrno = osGetLastError();
        rc = winLogError(SQLITE_IOERR_SHMMAP, pShmNode->lastErrno,
                 "winShmMap3", pDbFd->zPath);
        if( hMap ) osCloseHandle(hMap);
        goto shmpage_out;
      }

      pShmNode->aRegion[pShmNode->nRegion].pMap = pMap;
      pShmNode->aRegion[pShmNode->nRegion].hMap = hMap;
      pShmNode->nRegion++;
................................................................................
  if( pFile->pMapRegion ){
    if( !osUnmapViewOfFile(pFile->pMapRegion) ){
      pFile->lastErrno = osGetLastError();
      OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, pMapRegion=%p, "
               "rc=SQLITE_IOERR_MMAP\n", osGetCurrentProcessId(), pFile,
               pFile->pMapRegion));
      return winLogError(SQLITE_IOERR_MMAP, pFile->lastErrno,
                         "winUnmap1", pFile->zPath);
    }
    pFile->pMapRegion = 0;
    pFile->mmapSize = 0;
    pFile->mmapSizeActual = 0;
  }
  if( pFile->hMap!=NULL ){
    if( !osCloseHandle(pFile->hMap) ){
      pFile->lastErrno = osGetLastError();
      OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, hMap=%p, rc=SQLITE_IOERR_MMAP\n",
               osGetCurrentProcessId(), pFile, pFile->hMap));
      return winLogError(SQLITE_IOERR_MMAP, pFile->lastErrno,
                         "winUnmap2", pFile->zPath);
    }
    pFile->hMap = NULL;
  }
  OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, rc=SQLITE_OK\n",
           osGetCurrentProcessId(), pFile));
  return SQLITE_OK;
}
................................................................................
    pFd->hMap = osCreateFileMappingA(pFd->h, NULL, protect,
                                (DWORD)((nMap>>32) & 0xffffffff),
                                (DWORD)(nMap & 0xffffffff), NULL);
#endif
    if( pFd->hMap==NULL ){
      pFd->lastErrno = osGetLastError();
      rc = winLogError(SQLITE_IOERR_MMAP, pFd->lastErrno,
                       "winMapfile", pFd->zPath);
      /* Log the error, but continue normal operation using xRead/xWrite */
      OSTRACE(("MAP-FILE-CREATE pid=%lu, pFile=%p, rc=SQLITE_IOERR_MMAP\n",
               osGetCurrentProcessId(), pFd));
      return SQLITE_OK;
    }
    assert( (nMap % winSysInfo.dwPageSize)==0 );
    assert( sizeof(SIZE_T)==sizeof(sqlite3_int64) || nMap<=0xffffffff );
#if SQLITE_OS_WINRT
    pNew = osMapViewOfFileFromApp(pFd->hMap, flags, 0, (SIZE_T)nMap);
#else
    pNew = osMapViewOfFile(pFd->hMap, flags, 0, 0, (SIZE_T)nMap);
#endif
    if( pNew==NULL ){
      osCloseHandle(pFd->hMap);
      pFd->hMap = NULL;
      pFd->lastErrno = osGetLastError();
      winLogError(SQLITE_IOERR_MMAP, pFd->lastErrno,
                  "winMapfile", pFd->zPath);

      OSTRACE(("MAP-FILE-MAP pid=%lu, pFile=%p, rc=SQLITE_IOERR_MMAP\n",
               osGetCurrentProcessId(), pFd));
      return SQLITE_OK;
    }
    pFd->pMapRegion = pNew;
    pFd->mmapSize = nMap;
    pFd->mmapSizeActual = nMap;
  }

................................................................................
/****************************************************************************
**************************** sqlite3_vfs methods ****************************
**
** This division contains the implementation of methods on the
** sqlite3_vfs object.
*/






















/*
** Convert a UTF-8 filename into whatever form the underlying
** operating system wants filenames in.  Space to hold the result
** is obtained from malloc and must be freed by the calling
** function.
*/
static void *convertUtf8Filename(const char *zFilename){
  void *zConverted = 0;
  if( isNT() ){
    zConverted = utf8ToUnicode(zFilename);
  }
#ifdef SQLITE_WIN32_HAS_ANSI
  else{
    zConverted = sqlite3_win32_utf8_to_mbcs(zFilename);
  }
#endif
  /* caller will handle out of memory */
  return zConverted;
}

/*
** Maximum pathname length (in bytes) for windows.  The MAX_PATH macro is
** in characters, so we allocate 3 bytes per character assuming worst-case
** 3-bytes-per-character UTF8.
*/

#ifndef SQLITE_WIN32_MAX_PATH
#  define SQLITE_WIN32_MAX_PATH   (MAX_PATH*3)
#endif




/*
** Create a temporary file name in zBuf.  zBuf must be big enough to
** hold at pVfs->mxPathname characters.

*/
static int getTempname(int nBuf, char *zBuf){

  static char zChars[] =
    "abcdefghijklmnopqrstuvwxyz"
    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
    "0123456789";
  size_t i, j;
  int nTempPath;
  char zTempPath[SQLITE_WIN32_MAX_PATH+2];

  /* It's odd to simulate an io-error here, but really this is just
  ** using the io-error infrastructure to test that SQLite handles this
  ** function failing. 
  */
  SimulateIOError( return SQLITE_IOERR );
















  if( sqlite3_temp_directory ){
    sqlite3_snprintf(SQLITE_WIN32_MAX_PATH-30, zTempPath, "%s",

                     sqlite3_temp_directory);

  }



















































































#if !SQLITE_OS_WINRT
  else if( isNT() ){
    char *zMulti;

    WCHAR zWidePath[MAX_PATH];




    if( osGetTempPathW(MAX_PATH-30, zWidePath)==0 ){


      OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_GETTEMPPATH\n"));
      return SQLITE_IOERR_GETTEMPPATH;

    }
    zMulti = unicodeToUtf8(zWidePath);
    if( zMulti ){
      sqlite3_snprintf(SQLITE_WIN32_MAX_PATH-30, zTempPath, "%s", zMulti);

      sqlite3_free(zMulti);

    }else{


      OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
      return SQLITE_IOERR_NOMEM;
    }
  }
#ifdef SQLITE_WIN32_HAS_ANSI
  else{
    char *zUtf8;
    char zMbcsPath[SQLITE_WIN32_MAX_PATH];





    if( osGetTempPathA(SQLITE_WIN32_MAX_PATH-30, zMbcsPath)==0 ){

      OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_GETTEMPPATH\n"));
      return SQLITE_IOERR_GETTEMPPATH;

    }
    zUtf8 = sqlite3_win32_mbcs_to_utf8(zMbcsPath);
    if( zUtf8 ){
      sqlite3_snprintf(SQLITE_WIN32_MAX_PATH-30, zTempPath, "%s", zUtf8);
      sqlite3_free(zUtf8);
    }else{

      OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
      return SQLITE_IOERR_NOMEM;
    }
  }
#else
  else{
    /*
    ** Compiled without ANSI support and the current operating system
    ** is not Windows NT; therefore, just zero the temporary buffer.
    */
    memset(zTempPath, 0, SQLITE_WIN32_MAX_PATH+2);
  }
#endif /* SQLITE_WIN32_HAS_ANSI */
#else
  else{
    /*
    ** Compiled for WinRT and the sqlite3_temp_directory is not set;
    ** therefore, just zero the temporary buffer.
    */
    memset(zTempPath, 0, SQLITE_WIN32_MAX_PATH+2);
  }
#endif /* !SQLITE_OS_WINRT */

  /* Check that the output buffer is large enough for the temporary file 
  ** name. If it is not, return SQLITE_ERROR.
  */
  nTempPath = sqlite3Strlen30(zTempPath);

  if( (nTempPath + sqlite3Strlen30(SQLITE_TEMP_FILE_PREFIX) + 18) >= nBuf ){

    OSTRACE(("TEMP-FILENAME rc=SQLITE_ERROR\n"));
    return SQLITE_ERROR;

  }

  for(i=nTempPath; i>0 && zTempPath[i-1]=='\\'; i--){}
  zTempPath[i] = 0;

  sqlite3_snprintf(nBuf-18, zBuf, (nTempPath > 0) ?
                       "%s\\"SQLITE_TEMP_FILE_PREFIX : SQLITE_TEMP_FILE_PREFIX,
                   zTempPath);
  j = sqlite3Strlen30(zBuf);
  sqlite3_randomness(15, &zBuf[j]);
  for(i=0; i<15; i++, j++){
    zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
  }
  zBuf[j] = 0;
  zBuf[j+1] = 0;


  OSTRACE(("TEMP-FILENAME name=%s, rc=SQLITE_OK\n", zBuf));
  return SQLITE_OK;
}

/*
** Return TRUE if the named file is really a directory.  Return false if
................................................................................
** allocation failure.
*/
static int winIsDir(const void *zConverted){
  DWORD attr;
  int rc = 0;
  DWORD lastErrno;

  if( isNT() ){
    int cnt = 0;
    WIN32_FILE_ATTRIBUTE_DATA sAttrData;
    memset(&sAttrData, 0, sizeof(sAttrData));
    while( !(rc = osGetFileAttributesExW((LPCWSTR)zConverted,
                             GetFileExInfoStandard,
                             &sAttrData)) && retryIoerr(&cnt, &lastErrno) ){}
    if( !rc ){
      return 0; /* Invalid name? */
    }
    attr = sAttrData.dwFileAttributes;
#if SQLITE_OS_WINCE==0
  }else{
    attr = osGetFileAttributesA((char*)zConverted);
................................................................................
  return (attr!=INVALID_FILE_ATTRIBUTES) && (attr&FILE_ATTRIBUTE_DIRECTORY);
}

/*
** Open a file.
*/
static int winOpen(
  sqlite3_vfs *pVfs,        /* Not used */
  const char *zName,        /* Name of the file (UTF-8) */
  sqlite3_file *id,         /* Write the SQLite file handle here */
  int flags,                /* Open mode flags */
  int *pOutFlags            /* Status return flags */
){
  HANDLE h;
  DWORD lastErrno;
................................................................................
  void *zConverted;              /* Filename in OS encoding */
  const char *zUtf8Name = zName; /* Filename in UTF-8 encoding */
  int cnt = 0;

  /* If argument zPath is a NULL pointer, this function is required to open
  ** a temporary file. Use this buffer to store the file name in.
  */
  char zTmpname[SQLITE_WIN32_MAX_PATH+2];     /* Buffer used to create temp filename */

  int rc = SQLITE_OK;            /* Function Return Code */
#if !defined(NDEBUG) || SQLITE_OS_WINCE
  int eType = flags&0xFFFFFF00;  /* Type of file to open */
#endif

  int isExclusive  = (flags & SQLITE_OPEN_EXCLUSIVE);
................................................................................
  );

  assert( pFile!=0 );
  memset(pFile, 0, sizeof(winFile));
  pFile->h = INVALID_HANDLE_VALUE;

#if SQLITE_OS_WINRT
  if( !sqlite3_temp_directory ){
    sqlite3_log(SQLITE_ERROR,
        "sqlite3_temp_directory variable should be set for WinRT");
  }
#endif

  /* If the second argument to this function is NULL, generate a 
  ** temporary file name to use 
  */
  if( !zUtf8Name ){
    assert(isDelete && !isOpenJournal);
    rc = getTempname(SQLITE_WIN32_MAX_PATH+2, zTmpname);
    if( rc!=SQLITE_OK ){
      OSTRACE(("OPEN name=%s, rc=%s", zUtf8Name, sqlite3ErrName(rc)));
      return rc;
    }
    zUtf8Name = zTmpname;
  }

  /* Database filenames are double-zero terminated if they are not
  ** URIs with parameters.  Hence, they can always be passed into
  ** sqlite3_uri_parameter().
  */
  assert( (eType!=SQLITE_OPEN_MAIN_DB) || (flags & SQLITE_OPEN_URI) ||
        zUtf8Name[strlen(zUtf8Name)+1]==0 );

  /* Convert the filename to the system encoding. */
  zConverted = convertUtf8Filename(zUtf8Name);
  if( zConverted==0 ){

    OSTRACE(("OPEN name=%s, rc=SQLITE_IOERR_NOMEM", zUtf8Name));
    return SQLITE_IOERR_NOMEM;
  }

  if( winIsDir(zConverted) ){
    sqlite3_free(zConverted);

    OSTRACE(("OPEN name=%s, rc=SQLITE_CANTOPEN_ISDIR", zUtf8Name));
    return SQLITE_CANTOPEN_ISDIR;
  }

  if( isReadWrite ){
    dwDesiredAccess = GENERIC_READ | GENERIC_WRITE;
  }else{
................................................................................
  }
  /* Reports from the internet are that performance is always
  ** better if FILE_FLAG_RANDOM_ACCESS is used.  Ticket #2699. */
#if SQLITE_OS_WINCE
  dwFlagsAndAttributes |= FILE_FLAG_RANDOM_ACCESS;
#endif

  if( isNT() ){
#if SQLITE_OS_WINRT
    CREATEFILE2_EXTENDED_PARAMETERS extendedParameters;
    extendedParameters.dwSize = sizeof(CREATEFILE2_EXTENDED_PARAMETERS);
    extendedParameters.dwFileAttributes =
            dwFlagsAndAttributes & FILE_ATTRIBUTE_MASK;
    extendedParameters.dwFileFlags = dwFlagsAndAttributes & FILE_FLAG_MASK;
    extendedParameters.dwSecurityQosFlags = SECURITY_ANONYMOUS;
................................................................................
    extendedParameters.lpSecurityAttributes = NULL;
    extendedParameters.hTemplateFile = NULL;
    while( (h = osCreateFile2((LPCWSTR)zConverted,
                              dwDesiredAccess,
                              dwShareMode,
                              dwCreationDisposition,
                              &extendedParameters))==INVALID_HANDLE_VALUE &&
                              retryIoerr(&cnt, &lastErrno) ){
               /* Noop */
    }
#else
    while( (h = osCreateFileW((LPCWSTR)zConverted,
                              dwDesiredAccess,
                              dwShareMode, NULL,
                              dwCreationDisposition,
                              dwFlagsAndAttributes,
                              NULL))==INVALID_HANDLE_VALUE &&
                              retryIoerr(&cnt, &lastErrno) ){
               /* Noop */
    }
#endif
  }
#ifdef SQLITE_WIN32_HAS_ANSI
  else{
    while( (h = osCreateFileA((LPCSTR)zConverted,
                              dwDesiredAccess,
                              dwShareMode, NULL,
                              dwCreationDisposition,
                              dwFlagsAndAttributes,
                              NULL))==INVALID_HANDLE_VALUE &&
                              retryIoerr(&cnt, &lastErrno) ){
               /* Noop */
    }
  }
#endif
  logIoerr(cnt);

  OSTRACE(("OPEN file=%p, name=%s, access=%lx, rc=%s\n", h, zUtf8Name,
           dwDesiredAccess, (h==INVALID_HANDLE_VALUE) ? "failed" : "ok"));

  if( h==INVALID_HANDLE_VALUE ){
    pFile->lastErrno = lastErrno;
    winLogError(SQLITE_CANTOPEN, pFile->lastErrno, "winOpen", zUtf8Name);
    sqlite3_free(zConverted);

    if( isReadWrite && !isExclusive ){
      return winOpen(pVfs, zName, id, 
         ((flags|SQLITE_OPEN_READONLY) &
                     ~(SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE)),
         pOutFlags);
    }else{
      return SQLITE_CANTOPEN_BKPT;
................................................................................

#if SQLITE_OS_WINCE
  if( isReadWrite && eType==SQLITE_OPEN_MAIN_DB
       && (rc = winceCreateLock(zName, pFile))!=SQLITE_OK
  ){
    osCloseHandle(h);
    sqlite3_free(zConverted);

    OSTRACE(("OPEN-CE-LOCK name=%s, rc=%s\n", zName, sqlite3ErrName(rc)));
    return rc;
  }
  if( isTemp ){
    pFile->zDeleteOnClose = zConverted;
  }else
#endif
  {
    sqlite3_free(zConverted);

  }

  pFile->pMethod = &winIoMethod;
  pFile->pVfs = pVfs;
  pFile->h = h;
  if( isReadonly ){
    pFile->ctrlFlags |= WINFILE_RDONLY;
................................................................................
  void *zConverted;
  UNUSED_PARAMETER(pVfs);
  UNUSED_PARAMETER(syncDir);

  SimulateIOError(return SQLITE_IOERR_DELETE);
  OSTRACE(("DELETE name=%s, syncDir=%d\n", zFilename, syncDir));

  zConverted = convertUtf8Filename(zFilename);
  if( zConverted==0 ){

    return SQLITE_IOERR_NOMEM;
  }
  if( isNT() ){
    do {
#if SQLITE_OS_WINRT
      WIN32_FILE_ATTRIBUTE_DATA sAttrData;
      memset(&sAttrData, 0, sizeof(sAttrData));
      if ( osGetFileAttributesExW(zConverted, GetFileExInfoStandard,
                                  &sAttrData) ){
        attr = sAttrData.dwFileAttributes;
................................................................................
        rc = SQLITE_ERROR; /* Files only. */
        break;
      }
      if ( osDeleteFileW(zConverted) ){
        rc = SQLITE_OK; /* Deleted OK. */
        break;
      }
      if ( !retryIoerr(&cnt, &lastErrno) ){
        rc = SQLITE_ERROR; /* No more retries. */
        break;
      }
    } while(1);
  }
#ifdef SQLITE_WIN32_HAS_ANSI
  else{
................................................................................
        rc = SQLITE_ERROR; /* Files only. */
        break;
      }
      if ( osDeleteFileA(zConverted) ){
        rc = SQLITE_OK; /* Deleted OK. */
        break;
      }
      if ( !retryIoerr(&cnt, &lastErrno) ){
        rc = SQLITE_ERROR; /* No more retries. */
        break;
      }
    } while(1);
  }
#endif
  if( rc && rc!=SQLITE_IOERR_DELETE_NOENT ){
    rc = winLogError(SQLITE_IOERR_DELETE, lastErrno,
             "winDelete", zFilename);
  }else{
    logIoerr(cnt);
  }
  sqlite3_free(zConverted);
  OSTRACE(("DELETE name=%s, rc=%s\n", zFilename, sqlite3ErrName(rc)));
  return rc;
}

/*
................................................................................
  void *zConverted;
  UNUSED_PARAMETER(pVfs);

  SimulateIOError( return SQLITE_IOERR_ACCESS; );
  OSTRACE(("ACCESS name=%s, flags=%x, pResOut=%p\n",
           zFilename, flags, pResOut));

  zConverted = convertUtf8Filename(zFilename);
  if( zConverted==0 ){
    OSTRACE(("ACCESS name=%s, rc=SQLITE_IOERR_NOMEM\n", zFilename));
    return SQLITE_IOERR_NOMEM;
  }
  if( isNT() ){
    int cnt = 0;
    WIN32_FILE_ATTRIBUTE_DATA sAttrData;
    memset(&sAttrData, 0, sizeof(sAttrData));
    while( !(rc = osGetFileAttributesExW((LPCWSTR)zConverted,
                             GetFileExInfoStandard, 
                             &sAttrData)) && retryIoerr(&cnt, &lastErrno) ){}
    if( rc ){
      /* For an SQLITE_ACCESS_EXISTS query, treat a zero-length file
      ** as if it does not exist.
      */
      if(    flags==SQLITE_ACCESS_EXISTS
          && sAttrData.nFileSizeHigh==0 
          && sAttrData.nFileSizeLow==0 ){
        attr = INVALID_FILE_ATTRIBUTES;
      }else{
        attr = sAttrData.dwFileAttributes;
      }
    }else{
      logIoerr(cnt);
      if( lastErrno!=ERROR_FILE_NOT_FOUND && lastErrno!=ERROR_PATH_NOT_FOUND ){
        winLogError(SQLITE_IOERR_ACCESS, lastErrno, "winAccess", zFilename);
        sqlite3_free(zConverted);
        return SQLITE_IOERR_ACCESS;

      }else{
        attr = INVALID_FILE_ATTRIBUTES;
      }
    }
  }
#ifdef SQLITE_WIN32_HAS_ANSI
  else{
................................................................................
  }
  *pResOut = rc;
  OSTRACE(("ACCESS name=%s, pResOut=%p, *pResOut=%d, rc=SQLITE_OK\n",
           zFilename, pResOut, *pResOut));
  return SQLITE_OK;
}











/*
** Returns non-zero if the specified path name should be used verbatim.  If
** non-zero is returned from this function, the calling function must simply
** use the provided path name verbatim -OR- resolve it into a full path name
** using the GetFullPathName Win32 API function (if available).
*/
................................................................................
  /*
  ** If the path name starts with a forward slash or a backslash, it is either
  ** a legal UNC name, a volume relative path, or an absolute path name in the
  ** "Unix" format on Windows.  There is no easy way to differentiate between
  ** the final two cases; therefore, we return the safer return value of TRUE
  ** so that callers of this function will simply use it verbatim.
  */
  if ( zPathname[0]=='/' || zPathname[0]=='\\' ){
    return TRUE;
  }

  /*
  ** If the path name starts with a letter and a colon it is either a volume
  ** relative path or an absolute path.  Callers of this function must not
  ** attempt to treat it as a relative path name (i.e. they should simply use
  ** it verbatim).
  */
  if ( sqlite3Isalpha(zPathname[0]) && zPathname[1]==':' ){
    return TRUE;
  }

  /*
  ** If we get to this point, the path name should almost certainly be a purely
  ** relative one (i.e. not a UNC name, not absolute, and not volume relative).
  */
................................................................................
  int nFull,                    /* Size of output buffer in bytes */
  char *zFull                   /* Output buffer */
){
  
#if defined(__CYGWIN__)
  SimulateIOError( return SQLITE_ERROR );
  UNUSED_PARAMETER(nFull);
  assert( pVfs->mxPathname>=SQLITE_WIN32_MAX_PATH );
  assert( nFull>=pVfs->mxPathname );
  if ( sqlite3_data_directory && !winIsVerbatimPathname(zRelative) ){
    /*
    ** NOTE: We are dealing with a relative path name and the data
    **       directory has been set.  Therefore, use it as the basis
    **       for converting the relative path name to an absolute
    **       one by prepending the data directory and a slash.
    */
    char zOut[SQLITE_WIN32_MAX_PATH+1];



    if( cygwin_conv_path(CCP_POSIX_TO_WIN_A|CCP_RELATIVE, zRelative, zOut,
                         SQLITE_WIN32_MAX_PATH+1)<0 ){


      winLogError(SQLITE_CANTOPEN_FULLPATH, (DWORD)errno, "cygwin_conv_path",
                  zRelative);
      return SQLITE_CANTOPEN_FULLPATH;
    }
    sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s\\%s",
                     sqlite3_data_directory, zOut);

  }else{
    if( cygwin_conv_path(CCP_POSIX_TO_WIN_A, zRelative, zFull, nFull)<0 ){
      winLogError(SQLITE_CANTOPEN_FULLPATH, (DWORD)errno, "cygwin_conv_path",
                  zRelative);
      return SQLITE_CANTOPEN_FULLPATH;
    }
  }
  return SQLITE_OK;
#endif

#if (SQLITE_OS_WINCE || SQLITE_OS_WINRT) && !defined(__CYGWIN__)
  SimulateIOError( return SQLITE_ERROR );
................................................................................
  if ( sqlite3_data_directory && !winIsVerbatimPathname(zRelative) ){
    /*
    ** NOTE: We are dealing with a relative path name and the data
    **       directory has been set.  Therefore, use it as the basis
    **       for converting the relative path name to an absolute
    **       one by prepending the data directory and a backslash.
    */
    sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s\\%s",
                     sqlite3_data_directory, zRelative);
  }else{
    sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s", zRelative);
  }
  return SQLITE_OK;
#endif

#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && !defined(__CYGWIN__)
................................................................................
  DWORD nByte;
  void *zConverted;
  char *zOut;

  /* If this path name begins with "/X:", where "X" is any alphabetic
  ** character, discard the initial "/" from the pathname.
  */
  if( zRelative[0]=='/' && sqlite3Isalpha(zRelative[1]) && zRelative[2]==':' ){
    zRelative++;
  }

  /* It's odd to simulate an io-error here, but really this is just
  ** using the io-error infrastructure to test that SQLite handles this
  ** function failing. This function could fail if, for example, the
  ** current working directory has been unlinked.
................................................................................
  if ( sqlite3_data_directory && !winIsVerbatimPathname(zRelative) ){
    /*
    ** NOTE: We are dealing with a relative path name and the data
    **       directory has been set.  Therefore, use it as the basis
    **       for converting the relative path name to an absolute
    **       one by prepending the data directory and a backslash.
    */
    sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s\\%s",
                     sqlite3_data_directory, zRelative);
    return SQLITE_OK;
  }
  zConverted = convertUtf8Filename(zRelative);
  if( zConverted==0 ){
    return SQLITE_IOERR_NOMEM;
  }
  if( isNT() ){
    LPWSTR zTemp;
    nByte = osGetFullPathNameW((LPCWSTR)zConverted, 0, 0, 0);
    if( nByte==0 ){
      winLogError(SQLITE_ERROR, osGetLastError(),
                  "GetFullPathNameW1", zConverted);
      sqlite3_free(zConverted);
      return SQLITE_CANTOPEN_FULLPATH;

    }
    nByte += 3;
    zTemp = sqlite3MallocZero( nByte*sizeof(zTemp[0]) );
    if( zTemp==0 ){
      sqlite3_free(zConverted);
      return SQLITE_IOERR_NOMEM;
    }
    nByte = osGetFullPathNameW((LPCWSTR)zConverted, nByte, zTemp, 0);
    if( nByte==0 ){
      winLogError(SQLITE_ERROR, osGetLastError(),
                  "GetFullPathNameW2", zConverted);
      sqlite3_free(zConverted);
      sqlite3_free(zTemp);
      return SQLITE_CANTOPEN_FULLPATH;

    }
    sqlite3_free(zConverted);
    zOut = unicodeToUtf8(zTemp);
    sqlite3_free(zTemp);
  }
#ifdef SQLITE_WIN32_HAS_ANSI
  else{
    char *zTemp;
    nByte = osGetFullPathNameA((char*)zConverted, 0, 0, 0);
    if( nByte==0 ){
      winLogError(SQLITE_ERROR, osGetLastError(),
                  "GetFullPathNameA1", zConverted);
      sqlite3_free(zConverted);
      return SQLITE_CANTOPEN_FULLPATH;

    }
    nByte += 3;
    zTemp = sqlite3MallocZero( nByte*sizeof(zTemp[0]) );
    if( zTemp==0 ){
      sqlite3_free(zConverted);
      return SQLITE_IOERR_NOMEM;
    }
    nByte = osGetFullPathNameA((char*)zConverted, nByte, zTemp, 0);
    if( nByte==0 ){
      winLogError(SQLITE_ERROR, osGetLastError(),
                  "GetFullPathNameA2", zConverted);
      sqlite3_free(zConverted);
      sqlite3_free(zTemp);
      return SQLITE_CANTOPEN_FULLPATH;

    }
    sqlite3_free(zConverted);
    zOut = sqlite3_win32_mbcs_to_utf8(zTemp);
    sqlite3_free(zTemp);
  }
#endif
  if( zOut ){
................................................................................
*/
/*
** Interfaces for opening a shared library, finding entry points
** within the shared library, and closing the shared library.
*/
static void *winDlOpen(sqlite3_vfs *pVfs, const char *zFilename){
  HANDLE h;
  void *zConverted = convertUtf8Filename(zFilename);
  UNUSED_PARAMETER(pVfs);
  if( zConverted==0 ){
    return 0;
  }
  if( isNT() ){
#if SQLITE_OS_WINRT
    h = osLoadPackagedLibrary((LPCWSTR)zConverted, 0);
#else
    h = osLoadLibraryW((LPCWSTR)zConverted);
#endif
  }
#ifdef SQLITE_WIN32_HAS_ANSI
................................................................................
  }
#endif
  sqlite3_free(zConverted);
  return (void*)h;
}
static void winDlError(sqlite3_vfs *pVfs, int nBuf, char *zBufOut){
  UNUSED_PARAMETER(pVfs);
  getLastErrorMsg(osGetLastError(), nBuf, zBufOut);
}
static void (*winDlSym(sqlite3_vfs *pVfs,void *pH,const char *zSym))(void){
  UNUSED_PARAMETER(pVfs);
  return (void(*)(void))osGetProcAddressA((HANDLE)pH, zSym);
}
static void winDlClose(sqlite3_vfs *pVfs, void *pHandle){
  UNUSED_PARAMETER(pVfs);
................................................................................
**
** However if an error message is supplied, it will be incorporated
** by sqlite into the error message available to the user using
** sqlite3_errmsg(), possibly making IO errors easier to debug.
*/
static int winGetLastError(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
  UNUSED_PARAMETER(pVfs);
  return getLastErrorMsg(osGetLastError(), nBuf, zBuf);
}

/*
** Initialize and deinitialize the operating system interface.
*/
SQLITE_API int sqlite3_os_init(void){
  static sqlite3_vfs winVfs = {
    3,                   /* iVersion */
    sizeof(winFile),     /* szOsFile */
    SQLITE_WIN32_MAX_PATH, /* mxPathname */
    0,                   /* pNext */
    "win32",             /* zName */
    0,                   /* pAppData */
    winOpen,             /* xOpen */
    winDelete,           /* xDelete */
    winAccess,           /* xAccess */
    winFullPathname,     /* xFullPathname */
................................................................................
    winCurrentTime,      /* xCurrentTime */
    winGetLastError,     /* xGetLastError */
    winCurrentTimeInt64, /* xCurrentTimeInt64 */
    winSetSystemCall,    /* xSetSystemCall */
    winGetSystemCall,    /* xGetSystemCall */
    winNextSystemCall,   /* xNextSystemCall */
  };



























  /* Double-check that the aSyscall[] array has been constructed
  ** correctly.  See ticket [bb3a86e890c8e96ab] */
  assert( ArraySize(aSyscall)==74 );

  /* get memory map allocation granularity */
  memset(&winSysInfo, 0, sizeof(SYSTEM_INFO));
#if SQLITE_OS_WINRT
  osGetNativeSystemInfo(&winSysInfo);
#else
  osGetSystemInfo(&winSysInfo);
#endif
  assert( winSysInfo.dwAllocationGranularity>0 );
  assert( winSysInfo.dwPageSize>0 );

  sqlite3_vfs_register(&winVfs, 1);





  return SQLITE_OK; 
}

SQLITE_API int sqlite3_os_end(void){ 
#if SQLITE_OS_WINRT
  if( sleepObj!=NULL ){
    osCloseHandle(sleepObj);
................................................................................
**
** The first page is always a btree page.  The first 100 bytes of the first
** page contain a special header (the "file header") that describes the file.
** The format of the file header is as follows:
**
**   OFFSET   SIZE    DESCRIPTION
**      0      16     Header string: "SQLite format 3\000"
**     16       2     Page size in bytes.  
**     18       1     File format write version
**     19       1     File format read version
**     20       1     Bytes of unused space at the end of each page
**     21       1     Max embedded payload fraction
**     22       1     Min embedded payload fraction
**     23       1     Min leaf payload fraction
**     24       4     File change counter
**     28       4     Reserved for future use
**     32       4     First freelist page
**     36       4     Number of freelist pages in the file
**     40      60     15 4-byte meta values passed to higher layers
**
**     40       4     Schema cookie
**     44       4     File format of schema layer
**     48       4     Size of page cache
**     52       4     Largest root-page (auto/incr_vacuum)
**     56       4     1=UTF-8 2=UTF16le 3=UTF16be
**     60       4     User version
**     64       4     Incremental vacuum mode
**     68       4     unused
**     72       4     unused

**     76       4     unused
**
** All of the integer values are big-endian (most significant byte first).
**
** The file change counter is incremented when the database is changed
** This counter allows other processes to know when the file has changed
** and thus when they need to flush their cache.
**
................................................................................
  /* If the btree is already in a write-transaction, or it
  ** is already in a read-transaction and a read-transaction
  ** is requested, this is a no-op.
  */
  if( p->inTrans==TRANS_WRITE || (p->inTrans==TRANS_READ && !wrflag) ){
    goto trans_begun;
  }
  assert( IfNotOmitAV(pBt->bDoTruncate)==0 );

  /* Write transactions are not possible on a read-only database */
  if( (pBt->btsFlags & BTS_READ_ONLY)!=0 && wrflag ){
    rc = SQLITE_READONLY;
    goto trans_begun;
  }

................................................................................
    p->type = SQLITE_NULL;
    p->db = db;
  }
  return p;
}

/*
** Create a new sqlite3_value object, containing the value of pExpr.













**
** This only works for very simple expressions that consist of one constant
** token (i.e. "5", "5.1", "'a string'"). If the expression can
** be converted directly into a value, then the value is allocated and
** a pointer written to *ppVal. The caller is responsible for deallocating
** the value by passing it to sqlite3ValueFree() later on. If the expression
** cannot be converted to a value, then *ppVal is set to NULL.





*/













































SQLITE_PRIVATE int sqlite3ValueFromExpr(








  sqlite3 *db,              /* The database connection */
  Expr *pExpr,              /* The expression to evaluate */
  u8 enc,                   /* Encoding to use */
  u8 affinity,              /* Affinity to use */
  sqlite3_value **ppVal     /* Write the new value here */

){
  int op;
  char *zVal = 0;
  sqlite3_value *pVal = 0;
  int negInt = 1;
  const char *zNeg = "";


  if( !pExpr ){
    *ppVal = 0;
    return SQLITE_OK;
  }
  op = pExpr->op;

  /* op can only be TK_REGISTER if we have compiled with SQLITE_ENABLE_STAT3.
  ** The ifdef here is to enable us to achieve 100% branch test coverage even
  ** when SQLITE_ENABLE_STAT3 is omitted.
  */
#ifdef SQLITE_ENABLE_STAT3
  if( op==TK_REGISTER ) op = pExpr->op2;
#else
  if( NEVER(op==TK_REGISTER) ) op = pExpr->op2;
#endif

  /* Handle negative integers in a single step.  This is needed in the
  ** case when the value is -9223372036854775808.
................................................................................
    pExpr = pExpr->pLeft;
    op = pExpr->op;
    negInt = -1;
    zNeg = "-";
  }

  if( op==TK_STRING || op==TK_FLOAT || op==TK_INTEGER ){
    pVal = sqlite3ValueNew(db);
    if( pVal==0 ) goto no_mem;
    if( ExprHasProperty(pExpr, EP_IntValue) ){
      sqlite3VdbeMemSetInt64(pVal, (i64)pExpr->u.iValue*negInt);
    }else{
      zVal = sqlite3MPrintf(db, "%s%s", zNeg, pExpr->u.zToken);
      if( zVal==0 ) goto no_mem;
      sqlite3ValueSetStr(pVal, -1, zVal, SQLITE_UTF8, SQLITE_DYNAMIC);
................................................................................
    if( (op==TK_INTEGER || op==TK_FLOAT ) && affinity==SQLITE_AFF_NONE ){
      sqlite3ValueApplyAffinity(pVal, SQLITE_AFF_NUMERIC, SQLITE_UTF8);
    }else{
      sqlite3ValueApplyAffinity(pVal, affinity, SQLITE_UTF8);
    }
    if( pVal->flags & (MEM_Int|MEM_Real) ) pVal->flags &= ~MEM_Str;
    if( enc!=SQLITE_UTF8 ){
      sqlite3VdbeChangeEncoding(pVal, enc);
    }
  }else if( op==TK_UMINUS ) {
    /* This branch happens for multiple negative signs.  Ex: -(-5) */
    if( SQLITE_OK==sqlite3ValueFromExpr(db,pExpr->pLeft,enc,affinity,&pVal) ){


      sqlite3VdbeMemNumerify(pVal);
      if( pVal->u.i==SMALLEST_INT64 ){
        pVal->flags &= MEM_Int;
        pVal->flags |= MEM_Real;
        pVal->r = (double)LARGEST_INT64;
      }else{
        pVal->u.i = -pVal->u.i;
      }
      pVal->r = -pVal->r;
      sqlite3ValueApplyAffinity(pVal, affinity, enc);
    }
  }else if( op==TK_NULL ){
    pVal = sqlite3ValueNew(db);
    if( pVal==0 ) goto no_mem;
  }
#ifndef SQLITE_OMIT_BLOB_LITERAL
  else if( op==TK_BLOB ){
    int nVal;
    assert( pExpr->u.zToken[0]=='x' || pExpr->u.zToken[0]=='X' );
    assert( pExpr->u.zToken[1]=='\'' );
    pVal = sqlite3ValueNew(db);
    if( !pVal ) goto no_mem;
    zVal = &pExpr->u.zToken[2];
    nVal = sqlite3Strlen30(zVal)-1;
    assert( zVal[nVal]=='\'' );
    sqlite3VdbeMemSetStr(pVal, sqlite3HexToBlob(db, zVal, nVal), nVal/2,
                         0, SQLITE_DYNAMIC);
  }
#endif

  if( pVal ){
    sqlite3VdbeMemStoreType(pVal);
  }
  *ppVal = pVal;
  return SQLITE_OK;

no_mem:
  db->mallocFailed = 1;
  sqlite3DbFree(db, zVal);


  sqlite3ValueFree(pVal);
  *ppVal = 0;



  return SQLITE_NOMEM;
}

























































































































































































/*
** Change the string value of an sqlite3_value object
*/
SQLITE_PRIVATE void sqlite3ValueSetStr(
  sqlite3_value *v,     /* Value to be set */
  int n,                /* Length of string z */
  const void *z,        /* Text of the new string */
................................................................................


/*
** If the input FuncDef structure is ephemeral, then free it.  If
** the FuncDef is not ephermal, then do nothing.
*/
static void freeEphemeralFunction(sqlite3 *db, FuncDef *pDef){
  if( ALWAYS(pDef) && (pDef->flags & SQLITE_FUNC_EPHEM)!=0 ){
    sqlite3DbFree(db, pDef);
  }
}

static void vdbeFreeOpArray(sqlite3 *, Op *, int);

/*
................................................................................
        );
        sqlite3VdbePrintOp(out, i, &p->aOp[i]);
      }
      fclose(out);
    }
  }
#endif

  p->magic = VDBE_MAGIC_INIT;
  return p->rc & db->errMask;
}
 
/*
** Clean up and delete a VDBE after execution.  Return an integer which is
** the result code.  Write any error message text into *pzErrMsg.
................................................................................
      v->rc = rc = SQLITE_NOMEM;
    }
  }
  rc = sqlite3ApiExit(db, rc);
  sqlite3_mutex_leave(db->mutex);
  return rc;
}


/*
** Extract the user data from a sqlite3_context structure and return a
** pointer to it.
*/
SQLITE_API void *sqlite3_user_data(sqlite3_context *p){
  assert( p && p->pFunc );
................................................................................
** sqlite3_create_function16() routines that originally registered the
** application defined function.
*/
SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context *p){
  assert( p && p->pFunc );
  return p->s.db;
}














/*
** The following is the implementation of an SQL function that always
** fails with an error message stating that the function is used in the
** wrong context.  The sqlite3_overload_function() API might construct
** SQL function that use this routine so that the functions will exist
** for name resolution but are actually overloaded by the xFindFunction
................................................................................
    /* This happens if a malloc() inside a call to sqlite3_column_text() or
    ** sqlite3_column_text16() failed.  */
    goto no_mem;
  }
  assert( p->rc==SQLITE_OK || p->rc==SQLITE_BUSY );
  assert( p->bIsReader || p->readOnly!=0 );
  p->rc = SQLITE_OK;

  assert( p->explain==0 );
  p->pResultSet = 0;
  db->busyHandler.nBusy = 0;
  CHECK_FOR_INTERRUPT;
  sqlite3VdbeIOTraceSql(p);
#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
  if( db->xProgress ){
................................................................................
    ** external allocations out of mem[p2] and set mem[p2] to be
    ** an undefined integer.  Opcodes will either fill in the integer
    ** value or convert mem[p2] to a different type.
    */
    assert( pOp->opflags==sqlite3OpcodeProperty[pOp->opcode] );
    if( pOp->opflags & OPFLG_OUT2_PRERELEASE ){
      assert( pOp->p2>0 );
      assert( pOp->p2<=p->nMem );
      pOut = &aMem[pOp->p2];
      memAboutToChange(p, pOut);
      VdbeMemRelease(pOut);
      pOut->flags = MEM_Int;
    }

    /* Sanity checking on other operands */
#ifdef SQLITE_DEBUG
    if( (pOp->opflags & OPFLG_IN1)!=0 ){
      assert( pOp->p1>0 );
      assert( pOp->p1<=p->nMem );
      assert( memIsValid(&aMem[pOp->p1]) );
      REGISTER_TRACE(pOp->p1, &aMem[pOp->p1]);
    }
    if( (pOp->opflags & OPFLG_IN2)!=0 ){
      assert( pOp->p2>0 );
      assert( pOp->p2<=p->nMem );
      assert( memIsValid(&aMem[pOp->p2]) );
      REGISTER_TRACE(pOp->p2, &aMem[pOp->p2]);
    }
    if( (pOp->opflags & OPFLG_IN3)!=0 ){
      assert( pOp->p3>0 );
      assert( pOp->p3<=p->nMem );
      assert( memIsValid(&aMem[pOp->p3]) );
      REGISTER_TRACE(pOp->p3, &aMem[pOp->p3]);
    }
    if( (pOp->opflags & OPFLG_OUT2)!=0 ){
      assert( pOp->p2>0 );
      assert( pOp->p2<=p->nMem );
      memAboutToChange(p, &aMem[pOp->p2]);
    }
    if( (pOp->opflags & OPFLG_OUT3)!=0 ){
      assert( pOp->p3>0 );
      assert( pOp->p3<=p->nMem );
      memAboutToChange(p, &aMem[pOp->p3]);
    }
#endif
  
    switch( pOp->opcode ){

/*****************************************************************************
................................................................................

/* Opcode:  Gosub P1 P2 * * *
**
** Write the current address onto register P1
** and then jump to address P2.
*/
case OP_Gosub: {            /* jump */
  assert( pOp->p1>0 && pOp->p1<=p->nMem );
  pIn1 = &aMem[pOp->p1];
  assert( (pIn1->flags & MEM_Dyn)==0 );
  memAboutToChange(p, pIn1);
  pIn1->flags = MEM_Int;
  pIn1->u.i = pc;
  REGISTER_TRACE(pOp->p1, pIn1);
  pc = pOp->p2 - 1;
................................................................................
*/
case OP_Null: {           /* out2-prerelease */
#if 0  /* local variables moved into u.ab */
  int cnt;
  u16 nullFlag;
#endif /* local variables moved into u.ab */
  u.ab.cnt = pOp->p3-pOp->p2;
  assert( pOp->p3<=p->nMem );
  pOut->flags = u.ab.nullFlag = pOp->p1 ? (MEM_Null|MEM_Cleared) : MEM_Null;
  while( u.ab.cnt>0 ){
    pOut++;
    memAboutToChange(p, pOut);
    VdbeMemRelease(pOut);
    pOut->flags = u.ab.nullFlag;
    u.ab.cnt--;
................................................................................
  u.ad.p2 = pOp->p2;
  assert( u.ad.n>0 && u.ad.p1>0 && u.ad.p2>0 );
  assert( u.ad.p1+u.ad.n<=u.ad.p2 || u.ad.p2+u.ad.n<=u.ad.p1 );

  pIn1 = &aMem[u.ad.p1];
  pOut = &aMem[u.ad.p2];
  while( u.ad.n-- ){
    assert( pOut<=&aMem[p->nMem] );
    assert( pIn1<=&aMem[p->nMem] );
    assert( memIsValid(pIn1) );
    memAboutToChange(p, pOut);
    u.ad.zMalloc = pOut->zMalloc;
    pOut->zMalloc = 0;
    sqlite3VdbeMemMove(pOut, pIn1);
#ifdef SQLITE_DEBUG
    if( pOut->pScopyFrom>=&aMem[u.ad.p1] && pOut->pScopyFrom<&aMem[u.ad.p1+pOp->p3] ){
................................................................................
case OP_ResultRow: {
#if 0  /* local variables moved into u.af */
  Mem *pMem;
  int i;
#endif /* local variables moved into u.af */
  assert( p->nResColumn==pOp->p2 );
  assert( pOp->p1>0 );
  assert( pOp->p1+pOp->p2<=p->nMem+1 );

  /* If this statement has violated immediate foreign key constraints, do
  ** not return the number of rows modified. And do not RELEASE the statement
  ** transaction. It needs to be rolled back.  */
  if( SQLITE_OK!=(rc = sqlite3VdbeCheckFk(p, 0)) ){
    assert( db->flags&SQLITE_CountRows );
    assert( p->usesStmtJournal );
................................................................................
  sqlite3_value **apVal;
  int n;
#endif /* local variables moved into u.ai */

  u.ai.n = pOp->p5;
  u.ai.apVal = p->apArg;
  assert( u.ai.apVal || u.ai.n==0 );
  assert( pOp->p3>0 && pOp->p3<=p->nMem );
  pOut = &aMem[pOp->p3];
  memAboutToChange(p, pOut);

  assert( u.ai.n==0 || (pOp->p2>0 && pOp->p2+u.ai.n<=p->nMem+1) );
  assert( pOp->p3<pOp->p2 || pOp->p3>=pOp->p2+u.ai.n );
  u.ai.pArg = &aMem[pOp->p2];
  for(u.ai.i=0; u.ai.i<u.ai.n; u.ai.i++, u.ai.pArg++){
    assert( memIsValid(u.ai.pArg) );
    u.ai.apVal[u.ai.i] = u.ai.pArg;
    Deephemeralize(u.ai.pArg);
    sqlite3VdbeMemStoreType(u.ai.pArg);
................................................................................
  ** the pointer to u.ai.ctx.s so in case the user-function can use
  ** the already allocated buffer instead of allocating a new one.
  */
  sqlite3VdbeMemMove(&u.ai.ctx.s, pOut);
  MemSetTypeFlag(&u.ai.ctx.s, MEM_Null);

  u.ai.ctx.fErrorOrAux = 0;
  if( u.ai.ctx.pFunc->flags & SQLITE_FUNC_NEEDCOLL ){
    assert( pOp>aOp );
    assert( pOp[-1].p4type==P4_COLLSEQ );
    assert( pOp[-1].opcode==OP_CollSeq );
    u.ai.ctx.pColl = pOp[-1].p4.pColl;
  }
  db->lastRowid = lastRowid;
  (*u.ai.ctx.pFunc->xFunc)(&u.ai.ctx, u.ai.n, u.ai.apVal); /* IMP: R-24505-23230 */
................................................................................
  assert( u.al.pKeyInfo!=0 );
  u.al.p1 = pOp->p1;
  u.al.p2 = pOp->p2;
#if SQLITE_DEBUG
  if( aPermute ){
    int k, mx = 0;
    for(k=0; k<u.al.n; k++) if( aPermute[k]>mx ) mx = aPermute[k];
    assert( u.al.p1>0 && u.al.p1+mx<=p->nMem+1 );
    assert( u.al.p2>0 && u.al.p2+mx<=p->nMem+1 );
  }else{
    assert( u.al.p1>0 && u.al.p1+u.al.n<=p->nMem+1 );
    assert( u.al.p2>0 && u.al.p2+u.al.n<=p->nMem+1 );
  }
#endif /* SQLITE_DEBUG */
  for(u.al.i=0; u.al.i<u.al.n; u.al.i++){
    u.al.idx = aPermute ? aPermute[u.al.i] : u.al.i;
    assert( memIsValid(&aMem[u.al.p1+u.al.idx]) );
    assert( memIsValid(&aMem[u.al.p2+u.al.idx]) );
    REGISTER_TRACE(u.al.p1+u.al.idx, &aMem[u.al.p1+u.al.idx]);
................................................................................


  u.ao.p1 = pOp->p1;
  u.ao.p2 = pOp->p2;
  u.ao.pC = 0;
  memset(&u.ao.sMem, 0, sizeof(u.ao.sMem));
  assert( u.ao.p1<p->nCursor );
  assert( pOp->p3>0 && pOp->p3<=p->nMem );
  u.ao.pDest = &aMem[pOp->p3];
  memAboutToChange(p, u.ao.pDest);
  u.ao.zRec = 0;

  /* This block sets the variable u.ao.payloadSize to be the total number of
  ** bytes in the record.
  **
................................................................................
#endif /* local variables moved into u.ap */

  u.ap.zAffinity = pOp->p4.z;
  assert( u.ap.zAffinity!=0 );
  assert( u.ap.zAffinity[pOp->p2]==0 );
  pIn1 = &aMem[pOp->p1];
  while( (u.ap.cAff = *(u.ap.zAffinity++))!=0 ){
    assert( pIn1 <= &p->aMem[p->nMem] );
    assert( memIsValid(pIn1) );
    ExpandBlob(pIn1);
    applyAffinity(pIn1, u.ap.cAff, encoding);
    pIn1++;
  }
  break;
}
................................................................................
  ** of the record to data0.
  */
  u.aq.nData = 0;         /* Number of bytes of data space */
  u.aq.nHdr = 0;          /* Number of bytes of header space */
  u.aq.nZero = 0;         /* Number of zero bytes at the end of the record */
  u.aq.nField = pOp->p1;
  u.aq.zAffinity = pOp->p4.z;
  assert( u.aq.nField>0 && pOp->p2>0 && pOp->p2+u.aq.nField<=p->nMem+1 );
  u.aq.pData0 = &aMem[u.aq.nField];
  u.aq.nField = pOp->p2;
  u.aq.pLast = &u.aq.pData0[u.aq.nField-1];
  u.aq.file_format = p->minWriteFileFormat;

  /* Identify the output register */
  assert( pOp->p3<pOp->p1 || pOp->p3>=pOp->p1+pOp->p2 );
................................................................................
    u.aq.i += putVarint32(&u.aq.zNewRecord[u.aq.i], u.aq.serial_type);      /* serial type */
  }
  for(u.aq.pRec=u.aq.pData0; u.aq.pRec<=u.aq.pLast; u.aq.pRec++){  /* serial data */
    u.aq.i += sqlite3VdbeSerialPut(&u.aq.zNewRecord[u.aq.i], (int)(u.aq.nByte-u.aq.i), u.aq.pRec,u.aq.file_format);
  }
  assert( u.aq.i==u.aq.nByte );

  assert( pOp->p3>0 && pOp->p3<=p->nMem );
  pOut->n = (int)u.aq.nByte;
  pOut->flags = MEM_Blob | MEM_Dyn;
  pOut->xDel = 0;
  if( u.aq.nZero ){
    pOut->u.nZero = u.aq.nZero;
    pOut->flags |= MEM_Zero;
  }
................................................................................
      p->minWriteFileFormat = u.ay.pDb->pSchema->file_format;
    }
  }else{
    u.ay.wrFlag = 0;
  }
  if( pOp->p5 & OPFLAG_P2ISREG ){
    assert( u.ay.p2>0 );
    assert( u.ay.p2<=p->nMem );
    pIn2 = &aMem[u.ay.p2];
    assert( memIsValid(pIn2) );
    assert( (pIn2->flags & MEM_Int)!=0 );
    sqlite3VdbeMemIntegerify(pIn2);
    u.ay.p2 = (int)pIn2->u.i;
    /* The u.ay.p2 value always comes from a prior OP_CreateTable opcode and
    ** that opcode will always set the u.ay.p2 value to 2 or more or else fail.
................................................................................
  i64 R;                             /* Rowid stored in register P3 */
#endif /* local variables moved into u.bf */

  pIn3 = &aMem[pOp->p3];
  u.bf.aMx = &aMem[pOp->p4.i];
  /* Assert that the values of parameters P1 and P4 are in range. */
  assert( pOp->p4type==P4_INT32 );
  assert( pOp->p4.i>0 && pOp->p4.i<=p->nMem );
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );

  /* Find the index cursor. */
  u.bf.pCx = p->apCsr[pOp->p1];
  assert( u.bf.pCx->deferredMoveto==0 );
  u.bf.pCx->seekResult = 0;
  u.bf.pCx->cacheStatus = CACHE_STALE;
................................................................................
        if( p->pFrame ){
          for(u.bh.pFrame=p->pFrame; u.bh.pFrame->pParent; u.bh.pFrame=u.bh.pFrame->pParent);
          /* Assert that P3 is a valid memory cell. */
          assert( pOp->p3<=u.bh.pFrame->nMem );
          u.bh.pMem = &u.bh.pFrame->aMem[pOp->p3];
        }else{
          /* Assert that P3 is a valid memory cell. */
          assert( pOp->p3<=p->nMem );
          u.bh.pMem = &aMem[pOp->p3];
          memAboutToChange(p, u.bh.pMem);
        }
        assert( memIsValid(u.bh.pMem) );

        REGISTER_TRACE(pOp->p3, u.bh.pMem);
        sqlite3VdbeMemIntegerify(u.bh.pMem);
................................................................................
  VdbeCursor *pC;
  BtCursor *pCrsr;
  int res;
  UnpackedRecord r;
#endif /* local variables moved into u.bt */

  assert( pOp->p3>0 );
  assert( pOp->p2>0 && pOp->p2+pOp->p3<=p->nMem+1 );
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  u.bt.pC = p->apCsr[pOp->p1];
  assert( u.bt.pC!=0 );
  u.bt.pCrsr = u.bt.pC->pCursor;
  if( ALWAYS(u.bt.pCrsr!=0) ){
    u.bt.r.pKeyInfo = u.bt.pC->pKeyInfo;
    u.bt.r.nField = (u16)pOp->p3;
................................................................................
case OP_Clear: {
#if 0  /* local variables moved into u.bx */
  int nChange;
#endif /* local variables moved into u.bx */

  u.bx.nChange = 0;
  assert( p->readOnly==0 );

  assert( (p->btreeMask & (((yDbMask)1)<<pOp->p2))!=0 );
  rc = sqlite3BtreeClearTable(
      db->aDb[pOp->p2].pBt, pOp->p1, (pOp->p3 ? &u.bx.nChange : 0)
  );
  if( pOp->p3 ){
    p->nChange += u.bx.nChange;
    if( pOp->p3>0 ){
................................................................................
#endif /* local variables moved into u.ca */

  assert( p->bIsReader );
  u.ca.nRoot = pOp->p2;
  assert( u.ca.nRoot>0 );
  u.ca.aRoot = sqlite3DbMallocRaw(db, sizeof(int)*(u.ca.nRoot+1) );
  if( u.ca.aRoot==0 ) goto no_mem;
  assert( pOp->p3>0 && pOp->p3<=p->nMem );
  u.ca.pnErr = &aMem[pOp->p3];
  assert( (u.ca.pnErr->flags & MEM_Int)!=0 );
  assert( (u.ca.pnErr->flags & (MEM_Str|MEM_Blob))==0 );
  pIn1 = &aMem[pOp->p1];
  for(u.ca.j=0; u.ca.j<u.ca.nRoot; u.ca.j++){
    u.ca.aRoot[u.ca.j] = (int)sqlite3VdbeIntValue(&pIn1[u.ca.j]);
  }
................................................................................
  for(u.cg.i=0; u.cg.i<u.cg.n; u.cg.i++, u.cg.pRec++){
    assert( memIsValid(u.cg.pRec) );
    u.cg.apVal[u.cg.i] = u.cg.pRec;
    memAboutToChange(p, u.cg.pRec);
    sqlite3VdbeMemStoreType(u.cg.pRec);
  }
  u.cg.ctx.pFunc = pOp->p4.pFunc;
  assert( pOp->p3>0 && pOp->p3<=p->nMem );
  u.cg.ctx.pMem = u.cg.pMem = &aMem[pOp->p3];
  u.cg.pMem->n++;
  u.cg.ctx.s.flags = MEM_Null;
  u.cg.ctx.s.z = 0;
  u.cg.ctx.s.zMalloc = 0;
  u.cg.ctx.s.xDel = 0;
  u.cg.ctx.s.db = db;
  u.cg.ctx.isError = 0;
  u.cg.ctx.pColl = 0;
  u.cg.ctx.skipFlag = 0;
  if( u.cg.ctx.pFunc->flags & SQLITE_FUNC_NEEDCOLL ){
    assert( pOp>p->aOp );
    assert( pOp[-1].p4type==P4_COLLSEQ );
    assert( pOp[-1].opcode==OP_CollSeq );
    u.cg.ctx.pColl = pOp[-1].p4.pColl;
  }
  (u.cg.ctx.pFunc->xStep)(&u.cg.ctx, u.cg.n, u.cg.apVal); /* IMP: R-24505-23230 */
  if( u.cg.ctx.isError ){
................................................................................
** P4 argument is only needed for the degenerate case where
** the step function was not previously called.
*/
case OP_AggFinal: {
#if 0  /* local variables moved into u.ch */
  Mem *pMem;
#endif /* local variables moved into u.ch */
  assert( pOp->p1>0 && pOp->p1<=p->nMem );
  u.ch.pMem = &aMem[pOp->p1];
  assert( (u.ch.pMem->flags & ~(MEM_Null|MEM_Agg))==0 );
  rc = sqlite3VdbeMemFinalize(u.ch.pMem, pOp->p4.pFunc);
  if( rc ){
    sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3_value_text(u.ch.pMem));
  }
  sqlite3VdbeChangeEncoding(u.ch.pMem, encoding);
................................................................................
  const sqlite3_module *pModule;
  Mem *pDest;
  sqlite3_context sContext;
#endif /* local variables moved into u.co */

  VdbeCursor *pCur = p->apCsr[pOp->p1];
  assert( pCur->pVtabCursor );
  assert( pOp->p3>0 && pOp->p3<=p->nMem );
  u.co.pDest = &aMem[pOp->p3];
  memAboutToChange(p, u.co.pDest);
  if( pCur->nullRow ){
    sqlite3VdbeMemSetNull(u.co.pDest);
    break;
  }
  u.co.pVtab = pCur->pVtabCursor->pVtab;
................................................................................
SQLITE_PRIVATE int sqlite3WalkExpr(Walker *pWalker, Expr *pExpr){
  int rc;
  if( pExpr==0 ) return WRC_Continue;
  testcase( ExprHasProperty(pExpr, EP_TokenOnly) );
  testcase( ExprHasProperty(pExpr, EP_Reduced) );
  rc = pWalker->xExprCallback(pWalker, pExpr);
  if( rc==WRC_Continue
              && !ExprHasAnyProperty(pExpr,EP_TokenOnly) ){
    if( sqlite3WalkExpr(pWalker, pExpr->pLeft) ) return WRC_Abort;
    if( sqlite3WalkExpr(pWalker, pExpr->pRight) ) return WRC_Abort;
    if( ExprHasProperty(pExpr, EP_xIsSelect) ){
      if( sqlite3WalkSelect(pWalker, pExpr->x.pSelect) ) return WRC_Abort;
    }else{
      if( sqlite3WalkExprList(pWalker, pExpr->x.pList) ) return WRC_Abort;
    }
................................................................................
  db = pParse->db;
  pDup = sqlite3ExprDup(db, pOrig, 0);
  if( pDup==0 ) return;
  if( pOrig->op!=TK_COLUMN && zType[0]!='G' ){
    incrAggFunctionDepth(pDup, nSubquery);
    pDup = sqlite3PExpr(pParse, TK_AS, pDup, 0, 0);
    if( pDup==0 ) return;

    if( pEList->a[iCol].iAlias==0 ){
      pEList->a[iCol].iAlias = (u16)(++pParse->nAlias);
    }
    pDup->iTable = pEList->a[iCol].iAlias;
  }
  if( pExpr->op==TK_COLLATE ){
    pDup = sqlite3ExprAddCollateString(pParse, pDup, pExpr->u.zToken);
................................................................................
  */
  ExprSetProperty(pExpr, EP_Static);
  sqlite3ExprDelete(db, pExpr);
  memcpy(pExpr, pDup, sizeof(*pExpr));
  if( !ExprHasProperty(pExpr, EP_IntValue) && pExpr->u.zToken!=0 ){
    assert( (pExpr->flags & (EP_Reduced|EP_TokenOnly))==0 );
    pExpr->u.zToken = sqlite3DbStrDup(db, pExpr->u.zToken);
    pExpr->flags2 |= EP2_MallocedToken;
  }
  sqlite3DbFree(db, pDup);
}


/*
** Return TRUE if the name zCol occurs anywhere in the USING clause.
................................................................................
  struct SrcList_item *pMatch = 0;  /* The matching pSrcList item */
  NameContext *pTopNC = pNC;        /* First namecontext in the list */
  Schema *pSchema = 0;              /* Schema of the expression */
  int isTrigger = 0;

  assert( pNC );     /* the name context cannot be NULL. */
  assert( zCol );    /* The Z in X.Y.Z cannot be NULL */
  assert( !ExprHasAnyProperty(pExpr, EP_TokenOnly|EP_Reduced) );

  /* Initialize the node to no-match */
  pExpr->iTable = -1;
  pExpr->pTab = 0;
  ExprSetIrreducible(pExpr);

  /* Translate the schema name in zDb into a pointer to the corresponding
  ** schema.  If not found, pSchema will remain NULL and nothing will match
  ** resulting in an appropriate error message toward the end of this routine
  */
  if( zDb ){
    testcase( pNC->ncFlags & NC_PartIdx );
................................................................................
    sqlite3ErrorMsg(pParse,"%s prohibited in CHECK constraints", zMsg);
  }
}
#else
# define notValidCheckConstraint(P,N,M)
#endif















/*
** This routine is callback for sqlite3WalkExpr().
**
** Resolve symbolic names into TK_COLUMN operators for the current
** node in the expression tree.  Return 0 to continue the search down
** the tree or 2 to abort the tree walk.
................................................................................
  Parse *pParse;

  pNC = pWalker->u.pNC;
  assert( pNC!=0 );
  pParse = pNC->pParse;
  assert( pParse==pWalker->pParse );

  if( ExprHasAnyProperty(pExpr, EP_Resolved) ) return WRC_Prune;
  ExprSetProperty(pExpr, EP_Resolved);
#ifndef NDEBUG
  if( pNC->pSrcList && pNC->pSrcList->nAlloc>0 ){
    SrcList *pSrcList = pNC->pSrcList;
    int i;
    for(i=0; i<pNC->pSrcList->nSrc; i++){
      assert( pSrcList->a[i].iCursor>=0 && pSrcList->a[i].iCursor<pParse->nTab);
................................................................................
        if( pDef==0 ){
          no_such_func = 1;
        }else{
          wrong_num_args = 1;
        }
      }else{
        is_agg = pDef->xFunc==0;

















      }
#ifndef SQLITE_OMIT_AUTHORIZATION
      if( pDef ){
        auth = sqlite3AuthCheck(pParse, SQLITE_FUNCTION, 0, pDef->zName, 0);
        if( auth!=SQLITE_OK ){
          if( auth==SQLITE_DENY ){
            sqlite3ErrorMsg(pParse, "not authorized to use function: %s",
................................................................................
  if( op==TK_SELECT ){
    assert( pExpr->flags&EP_xIsSelect );
    return sqlite3ExprAffinity(pExpr->x.pSelect->pEList->a[0].pExpr);
  }
#ifndef SQLITE_OMIT_CAST
  if( op==TK_CAST ){
    assert( !ExprHasProperty(pExpr, EP_IntValue) );
    return sqlite3AffinityType(pExpr->u.zToken);
  }
#endif
  if( (op==TK_AGG_COLUMN || op==TK_COLUMN || op==TK_REGISTER) 
   && pExpr->pTab!=0
  ){
    /* op==TK_REGISTER && pExpr->pTab!=0 happens when pExpr was originally
    ** a TK_COLUMN but was previously evaluated and cached in a register */
................................................................................
** and the pExpr parameter is returned unchanged.
*/
SQLITE_PRIVATE Expr *sqlite3ExprAddCollateToken(Parse *pParse, Expr *pExpr, Token *pCollName){
  if( pCollName->n>0 ){
    Expr *pNew = sqlite3ExprAlloc(pParse->db, TK_COLLATE, pCollName, 1);
    if( pNew ){
      pNew->pLeft = pExpr;
      pNew->flags |= EP_Collate;
      pExpr = pNew;
    }
  }
  return pExpr;
}
SQLITE_PRIVATE Expr *sqlite3ExprAddCollateString(Parse *pParse, Expr *pExpr, const char *zC){
  Token s;
................................................................................
  assert( zC!=0 );
  s.z = zC;
  s.n = sqlite3Strlen30(s.z);
  return sqlite3ExprAddCollateToken(pParse, pExpr, &s);
}

/*
** Skip over any TK_COLLATE and/or TK_AS operators at the root of
** an expression.
*/
SQLITE_PRIVATE Expr *sqlite3ExprSkipCollate(Expr *pExpr){







  while( pExpr && (pExpr->op==TK_COLLATE || pExpr->op==TK_AS) ){
    pExpr = pExpr->pLeft;
  }

  return pExpr;
}

/*
** Return the collation sequence for the expression pExpr. If
** there is no defined collating sequence, return NULL.
**
................................................................................
** assigned.
*/
SQLITE_PRIVATE void sqlite3ExprAssignVarNumber(Parse *pParse, Expr *pExpr){
  sqlite3 *db = pParse->db;
  const char *z;

  if( pExpr==0 ) return;
  assert( !ExprHasAnyProperty(pExpr, EP_IntValue|EP_Reduced|EP_TokenOnly) );
  z = pExpr->u.zToken;
  assert( z!=0 );
  assert( z[0]!=0 );
  if( z[1]==0 ){
    /* Wildcard of the form "?".  Assign the next variable number */
    assert( z[0]=='?' );
    pExpr->iColumn = (ynVar)(++pParse->nVar);
................................................................................
/*
** Recursively delete an expression tree.
*/
SQLITE_PRIVATE void sqlite3ExprDelete(sqlite3 *db, Expr *p){
  if( p==0 ) return;
  /* Sanity check: Assert that the IntValue is non-negative if it exists */
  assert( !ExprHasProperty(p, EP_IntValue) || p->u.iValue>=0 );
  if( !ExprHasAnyProperty(p, EP_TokenOnly) ){
    sqlite3ExprDelete(db, p->pLeft);
    sqlite3ExprDelete(db, p->pRight);
    if( !ExprHasProperty(p, EP_Reduced) && (p->flags2 & EP2_MallocedToken)!=0 ){
      sqlite3DbFree(db, p->u.zToken);
    }
    if( ExprHasProperty(p, EP_xIsSelect) ){
      sqlite3SelectDelete(db, p->x.pSelect);
    }else{
      sqlite3ExprListDelete(db, p->x.pList);
    }
  }
  if( !ExprHasProperty(p, EP_Static) ){
................................................................................
** to reduce a pristine expression tree from the parser.  The implementation
** of dupedExprStructSize() contain multiple assert() statements that attempt
** to enforce this constraint.
*/
static int dupedExprStructSize(Expr *p, int flags){
  int nSize;
  assert( flags==EXPRDUP_REDUCE || flags==0 ); /* Only one flag value allowed */


  if( 0==(flags&EXPRDUP_REDUCE) ){
    nSize = EXPR_FULLSIZE;
  }else{
    assert( !ExprHasAnyProperty(p, EP_TokenOnly|EP_Reduced) );
    assert( !ExprHasProperty(p, EP_FromJoin) ); 
    assert( (p->flags2 & EP2_MallocedToken)==0 );
    assert( (p->flags2 & EP2_Irreducible)==0 );
    if( p->pLeft || p->pRight || p->x.pList ){
      nSize = EXPR_REDUCEDSIZE | EP_Reduced;
    }else{

      nSize = EXPR_TOKENONLYSIZE | EP_TokenOnly;
    }
  }
  return nSize;
}

/*
................................................................................
      }else{
        int nSize = exprStructSize(p);
        memcpy(zAlloc, p, nSize);
        memset(&zAlloc[nSize], 0, EXPR_FULLSIZE-nSize);
      }

      /* Set the EP_Reduced, EP_TokenOnly, and EP_Static flags appropriately. */
      pNew->flags &= ~(EP_Reduced|EP_TokenOnly|EP_Static);
      pNew->flags |= nStructSize & (EP_Reduced|EP_TokenOnly);
      pNew->flags |= staticFlag;

      /* Copy the p->u.zToken string, if any. */
      if( nToken ){
        char *zToken = pNew->u.zToken = (char*)&zAlloc[nNewSize];
        memcpy(zToken, p->u.zToken, nToken);
................................................................................
          pNew->x.pSelect = sqlite3SelectDup(db, p->x.pSelect, isReduced);
        }else{
          pNew->x.pList = sqlite3ExprListDup(db, p->x.pList, isReduced);
        }
      }

      /* Fill in pNew->pLeft and pNew->pRight. */
      if( ExprHasAnyProperty(pNew, EP_Reduced|EP_TokenOnly) ){
        zAlloc += dupedExprNodeSize(p, flags);
        if( ExprHasProperty(pNew, EP_Reduced) ){
          pNew->pLeft = exprDup(db, p->pLeft, EXPRDUP_REDUCE, &zAlloc);
          pNew->pRight = exprDup(db, p->pRight, EXPRDUP_REDUCE, &zAlloc);
        }
        if( pzBuffer ){
          *pzBuffer = zAlloc;
        }
      }else{
        pNew->flags2 = 0;
        if( !ExprHasAnyProperty(p, EP_TokenOnly) ){
          pNew->pLeft = sqlite3ExprDup(db, p->pLeft, 0);
          pNew->pRight = sqlite3ExprDup(db, p->pRight, 0);
        }
      }

    }
  }
................................................................................
**
*/
static int exprNodeIsConstant(Walker *pWalker, Expr *pExpr){

  /* If pWalker->u.i is 3 then any term of the expression that comes from
  ** the ON or USING clauses of a join disqualifies the expression
  ** from being considered constant. */
  if( pWalker->u.i==3 && ExprHasAnyProperty(pExpr, EP_FromJoin) ){
    pWalker->u.i = 0;
    return WRC_Abort;
  }

  switch( pExpr->op ){
    /* Consider functions to be constant if all their arguments are constant
    ** and pWalker->u.i==2 */
................................................................................
    case TK_UPLUS: {
      rc = sqlite3ExprIsInteger(p->pLeft, pValue);
      break;
    }
    case TK_UMINUS: {
      int v;
      if( sqlite3ExprIsInteger(p->pLeft, &v) ){
        assert( v!=-2147483648 );
        *pValue = -v;
        rc = 1;
      }
      break;
    }
    default: break;
  }
................................................................................
    eType = IN_INDEX_EPH;
    if( prNotFound ){
      *prNotFound = rMayHaveNull = ++pParse->nMem;
      sqlite3VdbeAddOp2(v, OP_Null, 0, *prNotFound);
    }else{
      testcase( pParse->nQueryLoop>0 );
      pParse->nQueryLoop = 0;
      if( pX->pLeft->iColumn<0 && !ExprHasAnyProperty(pX, EP_xIsSelect) ){
        eType = IN_INDEX_ROWID;
      }
    }
    sqlite3CodeSubselect(pParse, pX, rMayHaveNull, eType==IN_INDEX_ROWID);
    pParse->nQueryLoop = savedNQueryLoop;
  }else{
    pX->iTable = iTab;
................................................................................
  **    *  The right-hand side is a correlated subquery
  **    *  The right-hand side is an expression list containing variables
  **    *  We are inside a trigger
  **
  ** If all of the above are false, then we can run this code just once
  ** save the results, and reuse the same result on subsequent invocations.
  */
  if( !ExprHasAnyProperty(pExpr, EP_VarSelect) ){
    testAddr = sqlite3CodeOnce(pParse);
  }

#ifndef SQLITE_OMIT_EXPLAIN
  if( pParse->explain==2 ){
    char *zMsg = sqlite3MPrintf(
        pParse->db, "EXECUTE %s%s SUBQUERY %d", testAddr>=0?"":"CORRELATED ",
................................................................................
      pSel->pLimit = sqlite3PExpr(pParse, TK_INTEGER, 0, 0,
                                  &sqlite3IntTokens[1]);
      pSel->iLimit = 0;
      if( sqlite3Select(pParse, pSel, &dest) ){
        return 0;
      }
      rReg = dest.iSDParm;
      ExprSetIrreducible(pExpr);
      break;
    }
  }

  if( testAddr>=0 ){
    sqlite3VdbeJumpHere(v, testAddr);
  }
................................................................................
  for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
    int r = p->iReg;
    if( r>=iFrom && r<=iTo ) return 1;    /*NO_TEST*/
  }
  return 0;
}
#endif /* SQLITE_DEBUG || SQLITE_COVERAGE_TEST */











/*
** Generate code into the current Vdbe to evaluate the given
** expression.  Attempt to store the results in register "target".
** Return the register where results are stored.
**
** With this routine, there is no guarantee that results will
................................................................................
    }
#ifndef SQLITE_OMIT_CAST
    case TK_CAST: {
      /* Expressions of the form:   CAST(pLeft AS token) */
      int aff, to_op;
      inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
      assert( !ExprHasProperty(pExpr, EP_IntValue) );
      aff = sqlite3AffinityType(pExpr->u.zToken);
      to_op = aff - SQLITE_AFF_TEXT + OP_ToText;
      assert( to_op==OP_ToText    || aff!=SQLITE_AFF_TEXT    );
      assert( to_op==OP_ToBlob    || aff!=SQLITE_AFF_NONE    );
      assert( to_op==OP_ToNumeric || aff!=SQLITE_AFF_NUMERIC );
      assert( to_op==OP_ToInt     || aff!=SQLITE_AFF_INTEGER );
      assert( to_op==OP_ToReal    || aff!=SQLITE_AFF_REAL    );
      testcase( to_op==OP_ToText );
................................................................................
      int i;                 /* Loop counter */
      u8 enc = ENC(db);      /* The text encoding used by this database */
      CollSeq *pColl = 0;    /* A collating sequence */

      assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
      testcase( op==TK_CONST_FUNC );
      testcase( op==TK_FUNCTION );
      if( ExprHasAnyProperty(pExpr, EP_TokenOnly) ){
        pFarg = 0;
      }else{
        pFarg = pExpr->x.pList;
      }
      nFarg = pFarg ? pFarg->nExpr : 0;
      assert( !ExprHasProperty(pExpr, EP_IntValue) );
      zId = pExpr->u.zToken;
................................................................................
        break;
      }

      /* Attempt a direct implementation of the built-in COALESCE() and
      ** IFNULL() functions.  This avoids unnecessary evalation of
      ** arguments past the first non-NULL argument.
      */
      if( pDef->flags & SQLITE_FUNC_COALESCE ){
        int endCoalesce = sqlite3VdbeMakeLabel(v);
        assert( nFarg>=2 );
        sqlite3ExprCode(pParse, pFarg->a[0].pExpr, target);
        for(i=1; i<nFarg; i++){
          sqlite3VdbeAddOp2(v, OP_NotNull, target, endCoalesce);
          sqlite3ExprCacheRemove(pParse, target, 1);
          sqlite3ExprCachePush(pParse);
................................................................................
          sqlite3ExprCode(pParse, pFarg->a[i].pExpr, target);
          sqlite3ExprCachePop(pParse, 1);
        }
        sqlite3VdbeResolveLabel(v, endCoalesce);
        break;
      }










      if( pFarg ){
        r1 = sqlite3GetTempRange(pParse, nFarg);

        /* For length() and typeof() functions with a column argument,
        ** set the P5 parameter to the OP_Column opcode to OPFLAG_LENGTHARG
        ** or OPFLAG_TYPEOFARG respectively, to avoid unnecessary data
        ** loading.
        */
        if( (pDef->flags & (SQLITE_FUNC_LENGTH|SQLITE_FUNC_TYPEOF))!=0 ){
          u8 exprOp;
          assert( nFarg==1 );
          assert( pFarg->a[0].pExpr!=0 );
          exprOp = pFarg->a[0].pExpr->op;
          if( exprOp==TK_COLUMN || exprOp==TK_AGG_COLUMN ){
            assert( SQLITE_FUNC_LENGTH==OPFLAG_LENGTHARG );
            assert( SQLITE_FUNC_TYPEOF==OPFLAG_TYPEOFARG );

            testcase( pDef->flags==SQLITE_FUNC_LENGTH );
            pFarg->a[0].pExpr->op2 = pDef->flags;
          }
        }

        sqlite3ExprCachePush(pParse);     /* Ticket 2ea2425d34be */
        sqlite3ExprCodeExprList(pParse, pFarg, r1, 1);
        sqlite3ExprCachePop(pParse, 1);   /* Ticket 2ea2425d34be */
      }else{
................................................................................
        pDef = sqlite3VtabOverloadFunction(db, pDef, nFarg, pFarg->a[0].pExpr);
      }
#endif
      for(i=0; i<nFarg; i++){
        if( i<32 && sqlite3ExprIsConstant(pFarg->a[i].pExpr) ){
          constMask |= (1<<i);
        }
        if( (pDef->flags & SQLITE_FUNC_NEEDCOLL)!=0 && !pColl ){
          pColl = sqlite3ExprCollSeq(pParse, pFarg->a[i].pExpr);
        }
      }
      if( pDef->flags & SQLITE_FUNC_NEEDCOLL ){
        if( !pColl ) pColl = db->pDfltColl; 
        sqlite3VdbeAddOp4(v, OP_CollSeq, 0, 0, 0, (char *)pColl, P4_COLLSEQ);
      }
      sqlite3VdbeAddOp4(v, OP_Function, constMask, r1, target,
                        (char*)pDef, P4_FUNCDEF);
      sqlite3VdbeChangeP5(v, (u8)nFarg);
      if( nFarg ){
................................................................................
    **   CASE WHEN e1 THEN r1 WHEN e2 THEN r2 ... WHEN eN THEN rN ELSE y END
    **
    ** Form A is can be transformed into the equivalent form B as follows:
    **   CASE WHEN x=e1 THEN r1 WHEN x=e2 THEN r2 ...
    **        WHEN x=eN THEN rN ELSE y END
    **
    ** X (if it exists) is in pExpr->pLeft.
    ** Y is in pExpr->pRight.  The Y is also optional.  If there is no
    ** ELSE clause and no other term matches, then the result of the
    ** exprssion is NULL.
    ** Ei is in pExpr->pList->a[i*2] and Ri is pExpr->pList->a[i*2+1].
    **
    ** The result of the expression is the Ri for the first matching Ei,
    ** or if there is no matching Ei, the ELSE term Y, or if there is
    ** no ELSE term, NULL.
    */
    default: assert( op==TK_CASE ); {
................................................................................
      Expr opCompare;                   /* The X==Ei expression */
      Expr cacheX;                      /* Cached expression X */
      Expr *pX;                         /* The X expression */
      Expr *pTest = 0;                  /* X==Ei (form A) or just Ei (form B) */
      VVA_ONLY( int iCacheLevel = pParse->iCacheLevel; )

      assert( !ExprHasProperty(pExpr, EP_xIsSelect) && pExpr->x.pList );
      assert((pExpr->x.pList->nExpr % 2) == 0);
      assert(pExpr->x.pList->nExpr > 0);
      pEList = pExpr->x.pList;
      aListelem = pEList->a;
      nExpr = pEList->nExpr;
      endLabel = sqlite3VdbeMakeLabel(v);
      if( (pX = pExpr->pLeft)!=0 ){
        cacheX = *pX;
        testcase( pX->op==TK_COLUMN );
        testcase( pX->op==TK_REGISTER );
        cacheX.iTable = sqlite3ExprCodeTemp(pParse, pX, &regFree1);
        testcase( regFree1==0 );
        cacheX.op = TK_REGISTER;
        opCompare.op = TK_EQ;
        opCompare.pLeft = &cacheX;
        pTest = &opCompare;
        /* Ticket b351d95f9cd5ef17e9d9dbae18f5ca8611190001:
        ** The value in regFree1 might get SCopy-ed into the file result.
        ** So make sure that the regFree1 register is not reused for other
        ** purposes and possibly overwritten.  */
        regFree1 = 0;
      }
      for(i=0; i<nExpr; i=i+2){
        sqlite3ExprCachePush(pParse);
        if( pX ){
          assert( pTest!=0 );
          opCompare.pRight = aListelem[i].pExpr;
        }else{
          pTest = aListelem[i].pExpr;
        }
................................................................................
        testcase( aListelem[i+1].pExpr->op==TK_COLUMN );
        testcase( aListelem[i+1].pExpr->op==TK_REGISTER );
        sqlite3ExprCode(pParse, aListelem[i+1].pExpr, target);
        sqlite3VdbeAddOp2(v, OP_Goto, 0, endLabel);
        sqlite3ExprCachePop(pParse, 1);
        sqlite3VdbeResolveLabel(v, nextCase);
      }
      if( pExpr->pRight ){
        sqlite3ExprCachePush(pParse);
        sqlite3ExprCode(pParse, pExpr->pRight, target);
        sqlite3ExprCachePop(pParse, 1);
      }else{
        sqlite3VdbeAddOp2(v, OP_Null, 0, target);
      }
      assert( db->mallocFailed || pParse->nErr>0 
           || pParse->iCacheLevel==iCacheLevel );
      sqlite3VdbeResolveLabel(v, endLabel);
................................................................................
  ** no way for a TK_REGISTER to exist here.  But it seems prudent to
  ** keep the ALWAYS() in case the conditions above change with future
  ** modifications or enhancements. */
  if( ALWAYS(pExpr->op!=TK_REGISTER) ){  
    int iMem;
    iMem = ++pParse->nMem;
    sqlite3VdbeAddOp2(v, OP_Copy, inReg, iMem);
    pExpr->iTable = iMem;
    pExpr->op2 = pExpr->op;
    pExpr->op = TK_REGISTER;
  }
  return inReg;
}

#if defined(SQLITE_ENABLE_TREE_EXPLAIN)
/*
** Generate a human-readable explanation of an expression tree.
................................................................................
      sqlite3ExplainExpr(pOut, pExpr->pLeft);
      break;
    }
#ifndef SQLITE_OMIT_CAST
    case TK_CAST: {
      /* Expressions of the form:   CAST(pLeft AS token) */
      const char *zAff = "unk";
      switch( sqlite3AffinityType(pExpr->u.zToken) ){
        case SQLITE_AFF_TEXT:    zAff = "TEXT";     break;
        case SQLITE_AFF_NONE:    zAff = "NONE";     break;
        case SQLITE_AFF_NUMERIC: zAff = "NUMERIC";  break;
        case SQLITE_AFF_INTEGER: zAff = "INTEGER";  break;
        case SQLITE_AFF_REAL:    zAff = "REAL";     break;
      }
      sqlite3ExplainPrintf(pOut, "CAST-%s(", zAff);
................................................................................
      break;
    }

    case TK_AGG_FUNCTION:
    case TK_CONST_FUNC:
    case TK_FUNCTION: {
      ExprList *pFarg;       /* List of function arguments */
      if( ExprHasAnyProperty(pExpr, EP_TokenOnly) ){
        pFarg = 0;
      }else{
        pFarg = pExpr->x.pList;
      }
      if( op==TK_AGG_FUNCTION ){
        sqlite3ExplainPrintf(pOut, "AGG_FUNCTION%d:%s(",
                             pExpr->op2, pExpr->u.zToken);
................................................................................
  if( isAppropriateForFactoring(pExpr) ){
    int r1 = ++pParse->nMem;
    int r2 = sqlite3ExprCodeTarget(pParse, pExpr, r1);
    /* If r2!=r1, it means that register r1 is never used.  That is harmless
    ** but suboptimal, so we want to know about the situation to fix it.
    ** Hence the following assert: */
    assert( r2==r1 );
    pExpr->op2 = pExpr->op;
    pExpr->op = TK_REGISTER;
    pExpr->iTable = r2;
    return WRC_Prune;
  }
  return WRC_Continue;
}

/*
** Preevaluate constant subexpressions within pExpr and store the
................................................................................
  exprAnd.pRight = &compRight;
  compLeft.op = TK_GE;
  compLeft.pLeft = &exprX;
  compLeft.pRight = pExpr->x.pList->a[0].pExpr;
  compRight.op = TK_LE;
  compRight.pLeft = &exprX;
  compRight.pRight = pExpr->x.pList->a[1].pExpr;
  exprX.iTable = sqlite3ExprCodeTemp(pParse, &exprX, &regFree1);
  exprX.op2 = exprX.op;
  exprX.op = TK_REGISTER;
  if( jumpIfTrue ){
    sqlite3ExprIfTrue(pParse, &exprAnd, dest, jumpIfNull);
  }else{
    sqlite3ExprIfFalse(pParse, &exprAnd, dest, jumpIfNull);
  }
  sqlite3ReleaseTempReg(pParse, regFree1);

................................................................................
** just might result in some slightly slower code.  But returning
** an incorrect 0 or 1 could lead to a malfunction.
*/
SQLITE_PRIVATE int sqlite3ExprCompare(Expr *pA, Expr *pB, int iTab){
  if( pA==0||pB==0 ){
    return pB==pA ? 0 : 2;
  }
  assert( !ExprHasAnyProperty(pA, EP_TokenOnly|EP_Reduced) );
  assert( !ExprHasAnyProperty(pB, EP_TokenOnly|EP_Reduced) );
  if( ExprHasProperty(pA, EP_xIsSelect) || ExprHasProperty(pB, EP_xIsSelect) ){
    return 2;
  }
  if( (pA->flags & EP_Distinct)!=(pB->flags & EP_Distinct) ) return 2;
  if( pA->op!=pB->op && (pA->op!=TK_REGISTER || pA->op2!=pB->op) ){
    if( pA->op==TK_COLLATE && sqlite3ExprCompare(pA->pLeft, pB, iTab)<2 ){
      return 1;
................................................................................
      testcase( pExpr->op==TK_COLUMN );
      /* Check to see if the column is in one of the tables in the FROM
      ** clause of the aggregate query */
      if( ALWAYS(pSrcList!=0) ){
        struct SrcList_item *pItem = pSrcList->a;
        for(i=0; i<pSrcList->nSrc; i++, pItem++){
          struct AggInfo_col *pCol;
          assert( !ExprHasAnyProperty(pExpr, EP_TokenOnly|EP_Reduced) );
          if( pExpr->iTable==pItem->iCursor ){
            /* If we reach this point, it means that pExpr refers to a table
            ** that is in the FROM clause of the aggregate query.  
            **
            ** Make an entry for the column in pAggInfo->aCol[] if there
            ** is not an entry there already.
            */
................................................................................
              }
            }
            /* There is now an entry for pExpr in pAggInfo->aCol[] (either
            ** because it was there before or because we just created it).
            ** Convert the pExpr to be a TK_AGG_COLUMN referring to that
            ** pAggInfo->aCol[] entry.
            */
            ExprSetIrreducible(pExpr);
            pExpr->pAggInfo = pAggInfo;
            pExpr->op = TK_AGG_COLUMN;
            pExpr->iAgg = (i16)k;
            break;
          } /* endif pExpr->iTable==pItem->iCursor */
        } /* end loop over pSrcList */
      }
................................................................................
            }else{
              pItem->iDistinct = -1;
            }
          }
        }
        /* Make pExpr point to the appropriate pAggInfo->aFunc[] entry
        */
        assert( !ExprHasAnyProperty(pExpr, EP_TokenOnly|EP_Reduced) );
        ExprSetIrreducible(pExpr);
        pExpr->iAgg = (i16)i;
        pExpr->pAggInfo = pAggInfo;
        return WRC_Prune;
      }else{
        return WRC_Continue;
      }
    }
................................................................................
    return;
  }

  /* Ensure the default expression is something that sqlite3ValueFromExpr()
  ** can handle (i.e. not CURRENT_TIME etc.)
  */
  if( pDflt ){
    sqlite3_value *pVal;
    if( sqlite3ValueFromExpr(db, pDflt, SQLITE_UTF8, SQLITE_AFF_NONE, &pVal) ){
      db->mallocFailed = 1;
      return;
    }
    if( !pVal ){
      sqlite3ErrorMsg(pParse, "Cannot add a column with non-constant default");
      return;
................................................................................
  return;
}
#endif  /* SQLITE_ALTER_TABLE */

/************** End of alter.c ***********************************************/
/************** Begin file analyze.c *****************************************/
/*
** 2005 July 8
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
................................................................................
** to help it make better decisions about how to perform queries.
**
** The following system tables are or have been supported:
**
**    CREATE TABLE sqlite_stat1(tbl, idx, stat);
**    CREATE TABLE sqlite_stat2(tbl, idx, sampleno, sample);
**    CREATE TABLE sqlite_stat3(tbl, idx, nEq, nLt, nDLt, sample);

**
** Additional tables might be added in future releases of SQLite.
** The sqlite_stat2 table is not created or used unless the SQLite version
** is between 3.6.18 and 3.7.8, inclusive, and unless SQLite is compiled
** with SQLITE_ENABLE_STAT2.  The sqlite_stat2 table is deprecated.
** The sqlite_stat2 table is superseded by sqlite_stat3, which is only
** created and used by SQLite versions 3.7.9 and later and with
** SQLITE_ENABLE_STAT3 defined.  The fucntionality of sqlite_stat3
** is a superset of sqlite_stat2.  







**
** Format of sqlite_stat1:
**
** There is normally one row per index, with the index identified by the
** name in the idx column.  The tbl column is the name of the table to
** which the index belongs.  In each such row, the stat column will be
** a string consisting of a list of integers.  The first integer in this
** list is the number of rows in the index and in the table.  The second

** integer is the average number of rows in the index that have the same
** value in the first column of the index.  The third integer is the average
** number of rows in the index that have the same value for the first two
** columns.  The N-th integer (for N>1) is the average number of rows in 
** the index which have the same value for the first N-1 columns.  For
** a K-column index, there will be K+1 integers in the stat column.  If
** the index is unique, then the last integer will be 1.
................................................................................
** The format for sqlite_stat2 is recorded here for legacy reference.  This
** version of SQLite does not support sqlite_stat2.  It neither reads nor
** writes the sqlite_stat2 table.  This version of SQLite only supports
** sqlite_stat3.
**
** Format for sqlite_stat3:
**
** The sqlite_stat3 is an enhancement to sqlite_stat2.  A new name is
** used to avoid compatibility problems.  

**
** The format of the sqlite_stat3 table is similar to the format of







** the sqlite_stat2 table.  There are multiple entries for each index.
** The idx column names the index and the tbl column is the table of the
** index.  If the idx and tbl columns are the same, then the sample is
** of the INTEGER PRIMARY KEY.  The sample column is a value taken from
** the left-most column of the index.  The nEq column is the approximate
** number of entires in the index whose left-most column exactly matches


** the sample.  nLt is the approximate number of entires whose left-most









** column is less than the sample.  The nDLt column is the approximate
** number of distinct left-most entries in the index that are less than
** the sample.
**
** Future versions of SQLite might change to store a string containing
** multiple integers values in the nDLt column of sqlite_stat3.  The first
** integer will be the number of prior index entires that are distinct in
** the left-most column.  The second integer will be the number of prior index
** entries that are distinct in the first two columns.  The third integer
** will be the number of prior index entries that are distinct in the first
** three columns.  And so forth.  With that extension, the nDLt field is
** similar in function to the sqlite_stat1.stat field.
**
** There can be an arbitrary number of sqlite_stat3 entries per index.
** The ANALYZE command will typically generate sqlite_stat3 tables
** that contain between 10 and 40 samples which are distributed across
** the key space, though not uniformly, and which include samples with
** largest possible nEq values.










*/
#ifndef SQLITE_OMIT_ANALYZE















/*
** This routine generates code that opens the sqlite_stat1 table for
** writing with cursor iStatCur. If the library was built with the
** SQLITE_ENABLE_STAT3 macro defined, then the sqlite_stat3 table is
** opened for writing using cursor (iStatCur+1)



**
** If the sqlite_stat1 tables does not previously exist, it is created.
** Similarly, if the sqlite_stat3 table does not exist and the library
** is compiled with SQLITE_ENABLE_STAT3 defined, it is created. 
**
** Argument zWhere may be a pointer to a buffer containing a table name,
** or it may be a NULL pointer. If it is not NULL, then all entries in
** the sqlite_stat1 and (if applicable) sqlite_stat3 tables associated
** with the named table are deleted. If zWhere==0, then code is generated
** to delete all stat table entries.
*/
static void openStatTable(
  Parse *pParse,          /* Parsing context */
  int iDb,                /* The database we are looking in */
  int iStatCur,           /* Open the sqlite_stat1 table on this cursor */
  const char *zWhere,     /* Delete entries for this table or index */
  const char *zWhereType  /* Either "tbl" or "idx" */
){
  static const struct {
    const char *zName;
    const char *zCols;
  } aTable[] = {
    { "sqlite_stat1", "tbl,idx,stat" },



#ifdef SQLITE_ENABLE_STAT3
    { "sqlite_stat3", "tbl,idx,neq,nlt,ndlt,sample" },




#endif
  };

  int aRoot[] = {0, 0};
  u8 aCreateTbl[] = {0, 0};

  int i;
  sqlite3 *db = pParse->db;
  Db *pDb;
  Vdbe *v = sqlite3GetVdbe(pParse);



  if( v==0 ) return;
  assert( sqlite3BtreeHoldsAllMutexes(db) );
  assert( sqlite3VdbeDb(v)==db );
  pDb = &db->aDb[iDb];

  /* Create new statistic tables if they do not exist, or clear them
  ** if they do already exist.
  */
  for(i=0; i<ArraySize(aTable); i++){
    const char *zTab = aTable[i].zName;
    Table *pStat;
    if( (pStat = sqlite3FindTable(db, zTab, pDb->zName))==0 ){

      /* The sqlite_stat[12] table does not exist. Create it. Note that a 
      ** side-effect of the CREATE TABLE statement is to leave the rootpage 
      ** of the new table in register pParse->regRoot. This is important 
      ** because the OpenWrite opcode below will be needing it. */
      sqlite3NestedParse(pParse,
          "CREATE TABLE %Q.%s(%s)", pDb->zName, zTab, aTable[i].zCols
      );
      aRoot[i] = pParse->regRoot;
      aCreateTbl[i] = OPFLAG_P2ISREG;

    }else{
      /* The table already exists. If zWhere is not NULL, delete all entries 
      ** associated with the table zWhere. If zWhere is NULL, delete the
      ** entire contents of the table. */
      aRoot[i] = pStat->tnum;

      sqlite3TableLock(pParse, iDb, aRoot[i], 1, zTab);
      if( zWhere ){
        sqlite3NestedParse(pParse,

           "DELETE FROM %Q.%s WHERE %s=%Q", pDb->zName, zTab, zWhereType, zWhere
        );
      }else{
        /* The sqlite_stat[12] table already exists.  Delete all rows. */
        sqlite3VdbeAddOp2(v, OP_Clear, aRoot[i], iDb);
      }
    }
  }

  /* Open the sqlite_stat[13] tables for writing. */

  for(i=0; i<ArraySize(aTable); i++){
    sqlite3VdbeAddOp3(v, OP_OpenWrite, iStatCur+i, aRoot[i], iDb);
    sqlite3VdbeChangeP4(v, -1, (char *)3, P4_INT32);
    sqlite3VdbeChangeP5(v, aCreateTbl[i]);
  }
}

/*
** Recommended number of samples for sqlite_stat3
*/
#ifndef SQLITE_STAT3_SAMPLES
# define SQLITE_STAT3_SAMPLES 24
#endif

/*
** Three SQL functions - stat3_init(), stat3_push(), and stat3_pop() -
** share an instance of the following structure to hold their state
** information.
*/
typedef struct Stat3Accum Stat3Accum;
struct Stat3Accum {
  tRowcnt nRow;             /* Number of rows in the entire table */
  tRowcnt nPSample;         /* How often to do a periodic sample */
  int iMin;                 /* Index of entry with minimum nEq and hash */
  int mxSample;             /* Maximum number of samples to accumulate */
  int nSample;              /* Current number of samples */
  u32 iPrn;                 /* Pseudo-random number used for sampling */
  struct Stat3Sample {
    i64 iRowid;                /* Rowid in main table of the key */
    tRowcnt nEq;               /* sqlite_stat3.nEq */
    tRowcnt nLt;               /* sqlite_stat3.nLt */
    tRowcnt nDLt;              /* sqlite_stat3.nDLt */
    u8 isPSample;              /* True if a periodic sample */
    u32 iHash;                 /* Tiebreaker hash */
  } *a;                     /* An array of samples */
};

#ifdef SQLITE_ENABLE_STAT3
/*
** Implementation of the stat3_init(C,S) SQL function.  The two parameters
** are the number of rows in the table or index (C) and the number of samples
** to accumulate (S).
**
** This routine allocates the Stat3Accum object.
**
** The return value is the Stat3Accum object (P).
*/
static void stat3Init(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  Stat3Accum *p;
  tRowcnt nRow;
  int mxSample;
  int n;

  UNUSED_PARAMETER(argc);
  nRow = (tRowcnt)sqlite3_value_int64(argv[0]);
  mxSample = sqlite3_value_int(argv[1]);
  n = sizeof(*p) + sizeof(p->a[0])*mxSample;
  p = sqlite3MallocZero( n );
  if( p==0 ){
    sqlite3_result_error_nomem(context);
    return;
  }
  p->a = (struct Stat3Sample*)&p[1];
  p->nRow = nRow;
  p->mxSample = mxSample;
  p->nPSample = p->nRow/(mxSample/3+1) + 1;
  sqlite3_randomness(sizeof(p->iPrn), &p->iPrn);
  sqlite3_result_blob(context, p, sizeof(p), sqlite3_free);
}
static const FuncDef stat3InitFuncdef = {
  2,                /* nArg */
  SQLITE_UTF8,      /* iPrefEnc */
  0,                /* flags */
  0,                /* pUserData */
  0,                /* pNext */
  stat3Init,        /* xFunc */
  0,                /* xStep */
  0,                /* xFinalize */
  "stat3_init",     /* zName */
  0,                /* pHash */
  0                 /* pDestructor */
};


/*
** Implementation of the stat3_push(nEq,nLt,nDLt,rowid,P) SQL function.  The
** arguments describe a single key instance.  This routine makes the 
** decision about whether or not to retain this key for the sqlite_stat3
** table.
**
** The return value is NULL.
*/
static void stat3Push(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  Stat3Accum *p = (Stat3Accum*)sqlite3_value_blob(argv[4]);
  tRowcnt nEq = sqlite3_value_int64(argv[0]);
  tRowcnt nLt = sqlite3_value_int64(argv[1]);
  tRowcnt nDLt = sqlite3_value_int64(argv[2]);
  i64 rowid = sqlite3_value_int64(argv[3]);
  u8 isPSample = 0;
  u8 doInsert = 0;
  int iMin = p->iMin;
  struct Stat3Sample *pSample;
  int i;
  u32 h;

  UNUSED_PARAMETER(context);
  UNUSED_PARAMETER(argc);
  if( nEq==0 ) return;
  h = p->iPrn = p->iPrn*1103515245 + 12345;
  if( (nLt/p->nPSample)!=((nEq+nLt)/p->nPSample) ){
    doInsert = isPSample = 1;
  }else if( p->nSample<p->mxSample ){
    doInsert = 1;
  }else{
    if( nEq>p->a[iMin].nEq || (nEq==p->a[iMin].nEq && h>p->a[iMin].iHash) ){
      doInsert = 1;
    }
  }
  if( !doInsert ) return;
  if( p->nSample==p->mxSample ){
    assert( p->nSample - iMin - 1 >= 0 );
    memmove(&p->a[iMin], &p->a[iMin+1], sizeof(p->a[0])*(p->nSample-iMin-1));
    pSample = &p->a[p->nSample-1];
  }else{
    pSample = &p->a[p->nSample++];
  }
  pSample->iRowid = rowid;
  pSample->nEq = nEq;
  pSample->nLt = nLt;
  pSample->nDLt = nDLt;
  pSample->iHash = h;
  pSample->isPSample = isPSample;

  /* Find the new minimum */
  if( p->nSample==p->mxSample ){
    pSample = p->a;
    i = 0;
    while( pSample->isPSample ){
      i++;
      pSample++;
      assert( i<p->nSample );
    }
    nEq = pSample->nEq;
    h = pSample->iHash;
    iMin = i;
    for(i++, pSample++; i<p->nSample; i++, pSample++){
      if( pSample->isPSample ) continue;
      if( pSample->nEq<nEq
       || (pSample->nEq==nEq && pSample->iHash<h)
      ){
        iMin = i;
        nEq = pSample->nEq;
        h = pSample->iHash;
      }
    }
    p->iMin = iMin;
  }
}
static const FuncDef stat3PushFuncdef = {
  5,                /* nArg */
  SQLITE_UTF8,      /* iPrefEnc */
  0,                /* flags */
  0,                /* pUserData */
  0,                /* pNext */
  stat3Push,        /* xFunc */
  0,                /* xStep */
  0,                /* xFinalize */
  "stat3_push",     /* zName */
  0,                /* pHash */
  0                 /* pDestructor */
};

/*
** Implementation of the stat3_get(P,N,...) SQL function.  This routine is
** used to query the results.  Content is returned for the Nth sqlite_stat3
** row where N is between 0 and S-1 and S is the number of samples.  The
** value returned depends on the number of arguments.
**
**   argc==2    result:  rowid
**   argc==3    result:  nEq
**   argc==4    result:  nLt
**   argc==5    result:  nDLt
*/
static void stat3Get(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  int n = sqlite3_value_int(argv[1]);
  Stat3Accum *p = (Stat3Accum*)sqlite3_value_blob(argv[0]);

  assert( p!=0 );
  if( p->nSample<=n ) return;
  switch( argc ){
    case 2:  sqlite3_result_int64(context, p->a[n].iRowid); break;
    case 3:  sqlite3_result_int64(context, p->a[n].nEq);    break;
    case 4:  sqlite3_result_int64(context, p->a[n].nLt);    break;
    default: sqlite3_result_int64(context, p->a[n].nDLt);   break;
  }
}
static const FuncDef stat3GetFuncdef = {
  -1,               /* nArg */
  SQLITE_UTF8,      /* iPrefEnc */
  0,                /* flags */
  0,                /* pUserData */
  0,                /* pNext */
  stat3Get,         /* xFunc */
  0,                /* xStep */
  0,                /* xFinalize */
  "stat3_get",     /* zName */
  0,                /* pHash */
  0                 /* pDestructor */
};
#endif /* SQLITE_ENABLE_STAT3 */




/*
** Generate code to do an analysis of all indices associated with
** a single table.
*/
static void analyzeOneTable(
  Parse *pParse,   /* Parser context */
  Table *pTab,     /* Table whose indices are to be analyzed */
  Index *pOnlyIdx, /* If not NULL, only analyze this one index */
  int iStatCur,    /* Index of VdbeCursor that writes the sqlite_stat1 table */
  int iMem         /* Available memory locations begin here */

















































































































































































































































































































































































){
  sqlite3 *db = pParse->db;    /* Database handle */
  Index *pIdx;                 /* An index to being analyzed */
  int iIdxCur;                 /* Cursor open on index being analyzed */

  Vdbe *v;                     /* The virtual machine being built up */
  int i;                       /* Loop counter */
  int topOfLoop;               /* The top of the loop */
  int endOfLoop;               /* The end of the loop */
  int jZeroRows = -1;          /* Jump from here if number of rows is zero */
  int iDb;                     /* Index of database containing pTab */
  u8 needTableCnt = 1;         /* True to count the table */
  int regTabname = iMem++;     /* Register containing table name */
  int regIdxname = iMem++;     /* Register containing index name */
  int regStat1 = iMem++;       /* The stat column of sqlite_stat1 */
#ifdef SQLITE_ENABLE_STAT3
  int regNumEq = regStat1;     /* Number of instances.  Same as regStat1 */
  int regNumLt = iMem++;       /* Number of keys less than regSample */
  int regNumDLt = iMem++;      /* Number of distinct keys less than regSample */
  int regSample = iMem++;      /* The next sample value */
  int regRowid = regSample;    /* Rowid of a sample */
  int regAccum = iMem++;       /* Register to hold Stat3Accum object */
  int regLoop = iMem++;        /* Loop counter */
  int regCount = iMem++;       /* Number of rows in the table or index */
  int regTemp1 = iMem++;       /* Intermediate register */
  int regTemp2 = iMem++;       /* Intermediate register */
  int once = 1;                /* One-time initialization */
  int shortJump = 0;           /* Instruction address */
  int iTabCur = pParse->nTab++; /* Table cursor */
#endif
  int regCol = iMem++;         /* Content of a column in analyzed table */
  int regRec = iMem++;         /* Register holding completed record */
  int regTemp = iMem++;        /* Temporary use register */
  int regNewRowid = iMem++;    /* Rowid for the inserted record */







  v = sqlite3GetVdbe(pParse);
  if( v==0 || NEVER(pTab==0) ){
    return;
  }
  if( pTab->tnum==0 ){
    /* Do not gather statistics on views or virtual tables */
    return;
................................................................................
#ifndef SQLITE_OMIT_AUTHORIZATION
  if( sqlite3AuthCheck(pParse, SQLITE_ANALYZE, pTab->zName, 0,
      db->aDb[iDb].zName ) ){
    return;
  }
#endif

  /* Establish a read-lock on the table at the shared-cache level. */



  sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);


  iIdxCur = pParse->nTab++;


  sqlite3VdbeAddOp4(v, OP_String8, 0, regTabname, 0, pTab->zName, 0);

  for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
    int nCol;

    KeyInfo *pKey;
    int addrIfNot = 0;           /* address of OP_IfNot */
    int *aChngAddr;              /* Array of jump instruction addresses */




    if( pOnlyIdx && pOnlyIdx!=pIdx ) continue;
    if( pIdx->pPartIdxWhere==0 ) needTableCnt = 0;
    VdbeNoopComment((v, "Begin analysis of %s", pIdx->zName));
    nCol = pIdx->nColumn;
    aChngAddr = sqlite3DbMallocRaw(db, sizeof(int)*nCol);
    if( aChngAddr==0 ) continue;
    pKey = sqlite3IndexKeyinfo(pParse, pIdx);
    if( iMem+1+(nCol*2)>pParse->nMem ){
      pParse->nMem = iMem+1+(nCol*2);
    }

    /* Open a cursor to the index to be analyzed. */
    assert( iDb==sqlite3SchemaToIndex(db, pIdx->pSchema) );
    sqlite3VdbeAddOp4(v, OP_OpenRead, iIdxCur, pIdx->tnum, iDb,
        (char *)pKey, P4_KEYINFO_HANDOFF);
    VdbeComment((v, "%s", pIdx->zName));

    /* Populate the register containing the index name. */
    sqlite3VdbeAddOp4(v, OP_String8, 0, regIdxname, 0, pIdx->zName, 0);

#ifdef SQLITE_ENABLE_STAT3
    if( once ){
      once = 0;
      sqlite3OpenTable(pParse, iTabCur, iDb, pTab, OP_OpenRead);
    }
    sqlite3VdbeAddOp2(v, OP_Count, iIdxCur, regCount);
    sqlite3VdbeAddOp2(v, OP_Integer, SQLITE_STAT3_SAMPLES, regTemp1);
    sqlite3VdbeAddOp2(v, OP_Integer, 0, regNumEq);
    sqlite3VdbeAddOp2(v, OP_Integer, 0, regNumLt);
    sqlite3VdbeAddOp2(v, OP_Integer, -1, regNumDLt);
    sqlite3VdbeAddOp3(v, OP_Null, 0, regSample, regAccum);
    sqlite3VdbeAddOp4(v, OP_Function, 1, regCount, regAccum,
                      (char*)&stat3InitFuncdef, P4_FUNCDEF);
    sqlite3VdbeChangeP5(v, 2);
#endif /* SQLITE_ENABLE_STAT3 */

    /* The block of memory cells initialized here is used as follows.
    **
    **    iMem:                
    **        The total number of rows in the table.
    **
    **    iMem+1 .. iMem+nCol: 
    **        Number of distinct entries in index considering the 
    **        left-most N columns only, where N is between 1 and nCol, 
    **        inclusive.
    **
    **    iMem+nCol+1 .. Mem+2*nCol:  
    **        Previous value of indexed columns, from left to right.
    **
    ** Cells iMem through iMem+nCol are initialized to 0. The others are 
    ** initialized to contain an SQL NULL.
    */
    for(i=0; i<=nCol; i++){
      sqlite3VdbeAddOp2(v, OP_Integer, 0, iMem+i);
    }
    for(i=0; i<nCol; i++){
      sqlite3VdbeAddOp2(v, OP_Null, 0, iMem+nCol+i+1);
    }

    /* Start the analysis loop. This loop runs through all the entries in
    ** the index b-tree.  */
    endOfLoop = sqlite3VdbeMakeLabel(v);
    sqlite3VdbeAddOp2(v, OP_Rewind, iIdxCur, endOfLoop);
    topOfLoop = sqlite3VdbeCurrentAddr(v);
    sqlite3VdbeAddOp2(v, OP_AddImm, iMem, 1);  /* Increment row counter */

    for(i=0; i<nCol; i++){
      CollSeq *pColl;
      sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, i, regCol);
      if( i==0 ){
        /* Always record the very first row */
        addrIfNot = sqlite3VdbeAddOp1(v, OP_IfNot, iMem+1);
      }
      assert( pIdx->azColl!=0 );
      assert( pIdx->azColl[i]!=0 );
      pColl = sqlite3LocateCollSeq(pParse, pIdx->azColl[i]);
      aChngAddr[i] = sqlite3VdbeAddOp4(v, OP_Ne, regCol, 0, iMem+nCol+i+1,
                                      (char*)pColl, P4_COLLSEQ);
      sqlite3VdbeChangeP5(v, SQLITE_NULLEQ);
      VdbeComment((v, "jump if column %d changed", i));
#ifdef SQLITE_ENABLE_STAT3
      if( i==0 ){
        sqlite3VdbeAddOp2(v, OP_AddImm, regNumEq, 1);
        VdbeComment((v, "incr repeat count"));
      }
#endif
    }
    sqlite3VdbeAddOp2(v, OP_Goto, 0, endOfLoop);
    for(i=0; i<nCol; i++){
      sqlite3VdbeJumpHere(v, aChngAddr[i]);  /* Set jump dest for the OP_Ne */
      if( i==0 ){
        sqlite3VdbeJumpHere(v, addrIfNot);   /* Jump dest for OP_IfNot */
#ifdef SQLITE_ENABLE_STAT3
        sqlite3VdbeAddOp4(v, OP_Function, 1, regNumEq, regTemp2,
                          (char*)&stat3PushFuncdef, P4_FUNCDEF);
        sqlite3VdbeChangeP5(v, 5);
        sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, pIdx->nColumn, regRowid);
        sqlite3VdbeAddOp3(v, OP_Add, regNumEq, regNumLt, regNumLt);
        sqlite3VdbeAddOp2(v, OP_AddImm, regNumDLt, 1);
        sqlite3VdbeAddOp2(v, OP_Integer, 1, regNumEq);
#endif        
      }
      sqlite3VdbeAddOp2(v, OP_AddImm, iMem+i+1, 1);
      sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, i, iMem+nCol+i+1);
    }
    sqlite3DbFree(db, aChngAddr);

    /* Always jump here after updating the iMem+1...iMem+1+nCol counters */
    sqlite3VdbeResolveLabel(v, endOfLoop);

    sqlite3VdbeAddOp2(v, OP_Next, iIdxCur, topOfLoop);
    sqlite3VdbeAddOp1(v, OP_Close, iIdxCur);
#ifdef SQLITE_ENABLE_STAT3
    sqlite3VdbeAddOp4(v, OP_Function, 1, regNumEq, regTemp2,
                      (char*)&stat3PushFuncdef, P4_FUNCDEF);
    sqlite3VdbeChangeP5(v, 5);
    sqlite3VdbeAddOp2(v, OP_Integer, -1, regLoop);
    shortJump = 
    sqlite3VdbeAddOp2(v, OP_AddImm, regLoop, 1);
    sqlite3VdbeAddOp4(v, OP_Function, 1, regAccum, regTemp1,
                      (char*)&stat3GetFuncdef, P4_FUNCDEF);
    sqlite3VdbeChangeP5(v, 2);
    sqlite3VdbeAddOp1(v, OP_IsNull, regTemp1);
    sqlite3VdbeAddOp3(v, OP_NotExists, iTabCur, shortJump, regTemp1);
    sqlite3VdbeAddOp3(v, OP_Column, iTabCur, pIdx->aiColumn[0], regSample);
    sqlite3ColumnDefault(v, pTab, pIdx->aiColumn[0], regSample);
    sqlite3VdbeAddOp4(v, OP_Function, 1, regAccum, regNumEq,
                      (char*)&stat3GetFuncdef, P4_FUNCDEF);
    sqlite3VdbeChangeP5(v, 3);
    sqlite3VdbeAddOp4(v, OP_Function, 1, regAccum, regNumLt,
                      (char*)&stat3GetFuncdef, P4_FUNCDEF);
    sqlite3VdbeChangeP5(v, 4);
    sqlite3VdbeAddOp4(v, OP_Function, 1, regAccum, regNumDLt,
                      (char*)&stat3GetFuncdef, P4_FUNCDEF);
    sqlite3VdbeChangeP5(v, 5);
    sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 6, regRec, "bbbbbb", 0);
    sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur+1, regNewRowid);
    sqlite3VdbeAddOp3(v, OP_Insert, iStatCur+1, regRec, regNewRowid);
    sqlite3VdbeAddOp2(v, OP_Goto, 0, shortJump);
    sqlite3VdbeJumpHere(v, shortJump+2);
#endif        

    /* Store the results in sqlite_stat1.
    **
    ** The result is a single row of the sqlite_stat1 table.  The first
    ** two columns are the names of the table and index.  The third column
    ** is a string composed of a list of integer statistics about the
    ** index.  The first integer in the list is the total number of entries
    ** in the index.  There is one additional integer in the list for each
    ** column of the table.  This additional integer is a guess of how many
    ** rows of the table the index will select.  If D is the count of distinct
    ** values and K is the total number of rows, then the integer is computed
    ** as:
    **
    **        I = (K+D-1)/D
    **
    ** If K==0 then no entry is made into the sqlite_stat1 table.  
    ** If K>0 then it is always the case the D>0 so division by zero
    ** is never possible.
    */
    sqlite3VdbeAddOp2(v, OP_SCopy, iMem, regStat1);
    jZeroRows = sqlite3VdbeAddOp1(v, OP_IfNot, iMem);
    for(i=0; i<nCol; i++){
      sqlite3VdbeAddOp4(v, OP_String8, 0, regTemp, 0, " ", 0);
      sqlite3VdbeAddOp3(v, OP_Concat, regTemp, regStat1, regStat1);
      sqlite3VdbeAddOp3(v, OP_Add, iMem, iMem+i+1, regTemp);
      sqlite3VdbeAddOp2(v, OP_AddImm, regTemp, -1);
      sqlite3VdbeAddOp3(v, OP_Divide, iMem+i+1, regTemp, regTemp);
      sqlite3VdbeAddOp1(v, OP_ToInt, regTemp);
      sqlite3VdbeAddOp3(v, OP_Concat, regTemp, regStat1, regStat1);
    }
    if( pIdx->pPartIdxWhere!=0 ) sqlite3VdbeJumpHere(v, jZeroRows);
    sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 3, regRec, "aaa", 0);
    sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur, regNewRowid);
    sqlite3VdbeAddOp3(v, OP_Insert, iStatCur, regRec, regNewRowid);
    sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
    if( pIdx->pPartIdxWhere==0 ) sqlite3VdbeJumpHere(v, jZeroRows);
  }

  /* Create a single sqlite_stat1 entry containing NULL as the index
  ** name and the row count as the content.
  */
  if( pOnlyIdx==0 && needTableCnt ){
    sqlite3VdbeAddOp3(v, OP_OpenRead, iIdxCur, pTab->tnum, iDb);
    VdbeComment((v, "%s", pTab->zName));
    sqlite3VdbeAddOp2(v, OP_Count, iIdxCur, regStat1);
    sqlite3VdbeAddOp1(v, OP_Close, iIdxCur);
    jZeroRows = sqlite3VdbeAddOp1(v, OP_IfNot, regStat1);
    sqlite3VdbeAddOp2(v, OP_Null, 0, regIdxname);
    sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 3, regRec, "aaa", 0);
    sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur, regNewRowid);
    sqlite3VdbeAddOp3(v, OP_Insert, iStatCur, regRec, regNewRowid);






    sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
    sqlite3VdbeJumpHere(v, jZeroRows);
  }
  if( pParse->nMem<regRec ) pParse->nMem = regRec;
}


/*
** Generate code that will cause the most recent index analysis to
** be loaded into internal hash tables where is can be used.
*/
................................................................................
*/
static void analyzeDatabase(Parse *pParse, int iDb){
  sqlite3 *db = pParse->db;
  Schema *pSchema = db->aDb[iDb].pSchema;    /* Schema of database iDb */
  HashElem *k;
  int iStatCur;
  int iMem;


  sqlite3BeginWriteOperation(pParse, 0, iDb);
  iStatCur = pParse->nTab;
  pParse->nTab += 3;
  openStatTable(pParse, iDb, iStatCur, 0, 0);
  iMem = pParse->nMem+1;

  assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
  for(k=sqliteHashFirst(&pSchema->tblHash); k; k=sqliteHashNext(k)){
    Table *pTab = (Table*)sqliteHashData(k);
    analyzeOneTable(pParse, pTab, 0, iStatCur, iMem);
  }
  loadAnalysis(pParse, iDb);
}

/*
** Generate code that will do an analysis of a single table in
** a database.  If pOnlyIdx is not NULL then it is a single index
................................................................................
  iStatCur = pParse->nTab;
  pParse->nTab += 3;
  if( pOnlyIdx ){
    openStatTable(pParse, iDb, iStatCur, pOnlyIdx->zName, "idx");
  }else{
    openStatTable(pParse, iDb, iStatCur, pTab->zName, "tbl");
  }
  analyzeOneTable(pParse, pTab, pOnlyIdx, iStatCur, pParse->nMem+1);
  loadAnalysis(pParse, iDb);
}

/*
** Generate code for the ANALYZE command.  The parser calls this routine
** when it recognizes an ANALYZE command.
**
................................................................................
** callback routine.
*/
typedef struct analysisInfo analysisInfo;
struct analysisInfo {
  sqlite3 *db;
  const char *zDatabase;
};















































/*
** This callback is invoked once for each index when reading the
** sqlite_stat1 table.  
**
**     argv[0] = name of the table
**     argv[1] = name of the index (might be NULL)
................................................................................
** Entries for which argv[1]==NULL simply record the number of rows in
** the table.
*/
static int analysisLoader(void *pData, int argc, char **argv, char **NotUsed){
  analysisInfo *pInfo = (analysisInfo*)pData;
  Index *pIndex;
  Table *pTable;
  int i, c, n;
  tRowcnt v;
  const char *z;

  assert( argc==3 );
  UNUSED_PARAMETER2(NotUsed, argc);

  if( argv==0 || argv[0]==0 || argv[2]==0 ){
    return 0;
................................................................................
    return 0;
  }
  if( argv[1] ){
    pIndex = sqlite3FindIndex(pInfo->db, argv[1], pInfo->zDatabase);
  }else{
    pIndex = 0;
  }
  n = pIndex ? pIndex->nColumn : 0;
  z = argv[2];
  for(i=0; *z && i<=n; i++){
    v = 0;
    while( (c=z[0])>='0' && c<='9' ){
      v = v*10 + c - '0';
      z++;
    }


    if( i==0 && (pIndex==0 || pIndex->pPartIdxWhere==0) ){




      if( v>0 ) pTable->nRowEst = v;
      if( pIndex==0 ) break;
    }
    pIndex->aiRowEst[i] = v;
    if( *z==' ' ) z++;
    if( strcmp(z, "unordered")==0 ){
      pIndex->bUnordered = 1;
      break;
    }
  }
  return 0;
}

/*
** If the Index.aSample variable is not NULL, delete the aSample[] array
** and its contents.
*/
SQLITE_PRIVATE void sqlite3DeleteIndexSamples(sqlite3 *db, Index *pIdx){
#ifdef SQLITE_ENABLE_STAT3
  if( pIdx->aSample ){
    int j;
    for(j=0; j<pIdx->nSample; j++){
      IndexSample *p = &pIdx->aSample[j];
      if( p->eType==SQLITE_TEXT || p->eType==SQLITE_BLOB ){
        sqlite3DbFree(db, p->u.z);
      }
    }
    sqlite3DbFree(db, pIdx->aSample);
  }
  if( db && db->pnBytesFreed==0 ){
    pIdx->nSample = 0;
    pIdx->aSample = 0;
  }
#else
  UNUSED_PARAMETER(db);
  UNUSED_PARAMETER(pIdx);
#endif
}

#ifdef SQLITE_ENABLE_STAT3
/*
** Load content from the sqlite_stat3 table into the Index.aSample[]
** arrays of all indices.
*/














































static int loadStat3(sqlite3 *db, const char *zDb){






  int rc;                       /* Result codes from subroutines */
  sqlite3_stmt *pStmt = 0;      /* An SQL statement being run */
  char *zSql;                   /* Text of the SQL statement */
  Index *pPrevIdx = 0;          /* Previous index in the loop */
  int idx = 0;                  /* slot in pIdx->aSample[] for next sample */
  int eType;                    /* Datatype of a sample */
  IndexSample *pSample;         /* A slot in pIdx->aSample[] */

  assert( db->lookaside.bEnabled==0 );
  if( !sqlite3FindTable(db, "sqlite_stat3", zDb) ){
    return SQLITE_OK;
  }

  zSql = sqlite3MPrintf(db, 
      "SELECT idx,count(*) FROM %Q.sqlite_stat3"
      " GROUP BY idx", zDb);
  if( !zSql ){
    return SQLITE_NOMEM;
  }
  rc = sqlite3_prepare(db, zSql, -1, &pStmt, 0);
  sqlite3DbFree(db, zSql);
  if( rc ) return rc;

  while( sqlite3_step(pStmt)==SQLITE_ROW ){



    char *zIndex;   /* Index name */
    Index *pIdx;    /* Pointer to the index object */
    int nSample;    /* Number of samples */




    zIndex = (char *)sqlite3_column_text(pStmt, 0);
    if( zIndex==0 ) continue;
    nSample = sqlite3_column_int(pStmt, 1);
    pIdx = sqlite3FindIndex(db, zIndex, zDb);
    if( pIdx==0 ) continue;
    assert( pIdx->nSample==0 );






    pIdx->nSample = nSample;




    pIdx->aSample = sqlite3DbMallocZero(db, nSample*sizeof(IndexSample));
    pIdx->avgEq = pIdx->aiRowEst[1];
    if( pIdx->aSample==0 ){
      db->mallocFailed = 1;
      sqlite3_finalize(pStmt);
      return SQLITE_NOMEM;
    }








  }
  rc = sqlite3_finalize(pStmt);
  if( rc ) return rc;

  zSql = sqlite3MPrintf(db, 
      "SELECT idx,neq,nlt,ndlt,sample FROM %Q.sqlite_stat3", zDb);
  if( !zSql ){
    return SQLITE_NOMEM;
  }
  rc = sqlite3_prepare(db, zSql, -1, &pStmt, 0);
  sqlite3DbFree(db, zSql);
  if( rc ) return rc;

  while( sqlite3_step(pStmt)==SQLITE_ROW ){
    char *zIndex;   /* Index name */
    Index *pIdx;    /* Pointer to the index object */
    int i;          /* Loop counter */
    tRowcnt sumEq;  /* Sum of the nEq values */

    zIndex = (char *)sqlite3_column_text(pStmt, 0);
    if( zIndex==0 ) continue;
    pIdx = sqlite3FindIndex(db, zIndex, zDb);
    if( pIdx==0 ) continue;
    if( pIdx==pPrevIdx ){
      idx++;
    }else{
      pPrevIdx = pIdx;
      idx = 0;
    }
    assert( idx<pIdx->nSample );
    pSample = &pIdx->aSample[idx];
    pSample->nEq = (tRowcnt)sqlite3_column_int64(pStmt, 1);
    pSample->nLt = (tRowcnt)sqlite3_column_int64(pStmt, 2);
    pSample->nDLt = (tRowcnt)sqlite3_column_int64(pStmt, 3);
    if( idx==pIdx->nSample-1 ){
      if( pSample->nDLt>0 ){
        for(i=0, sumEq=0; i<=idx-1; i++) sumEq += pIdx->aSample[i].nEq;
        pIdx->avgEq = (pSample->nLt - sumEq)/pSample->nDLt;
      }
      if( pIdx->avgEq<=0 ) pIdx->avgEq = 1;
    }
    eType = sqlite3_column_type(pStmt, 4);
    pSample->eType = (u8)eType;
    switch( eType ){
      case SQLITE_INTEGER: {
        pSample->u.i = sqlite3_column_int64(pStmt, 4);
        break;
      }
      case SQLITE_FLOAT: {
        pSample->u.r = sqlite3_column_double(pStmt, 4);
        break;
      }
      case SQLITE_NULL: {
        break;
      }
      default: assert( eType==SQLITE_TEXT || eType==SQLITE_BLOB ); {
        const char *z = (const char *)(
              (eType==SQLITE_BLOB) ?
              sqlite3_column_blob(pStmt, 4):
              sqlite3_column_text(pStmt, 4)
           );
        int n = z ? sqlite3_column_bytes(pStmt, 4) : 0;
        pSample->nByte = n;
        if( n < 1){
          pSample->u.z = 0;
        }else{
          pSample->u.z = sqlite3DbMallocRaw(db, n);
          if( pSample->u.z==0 ){
            db->mallocFailed = 1;
            sqlite3_finalize(pStmt);
            return SQLITE_NOMEM;
          }
          memcpy(pSample->u.z, z, n);
        }
      }
    }
  }
  return sqlite3_finalize(pStmt);
}
#endif /* SQLITE_ENABLE_STAT3 */

/*
** Load the content of the sqlite_stat1 and sqlite_stat3 tables. The
** contents of sqlite_stat1 are used to populate the Index.aiRowEst[]
** arrays. The contents of sqlite_stat3 are used to populate the



** Index.aSample[] arrays.
**
** If the sqlite_stat1 table is not present in the database, SQLITE_ERROR
** is returned. In this case, even if SQLITE_ENABLE_STAT3 was defined 
** during compilation and the sqlite_stat3 table is present, no data is 
** read from it.
**
** If SQLITE_ENABLE_STAT3 was defined during compilation and the 
** sqlite_stat3 table is not present in the database, SQLITE_ERROR is
** returned. However, in this case, data is read from the sqlite_stat1
** table (if it is present) before returning.
**
** If an OOM error occurs, this function always sets db->mallocFailed.
** This means if the caller does not care about other errors, the return
** code may be ignored.
*/
................................................................................
  assert( db->aDb[iDb].pBt!=0 );

  /* Clear any prior statistics */
  assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
  for(i=sqliteHashFirst(&db->aDb[iDb].pSchema->idxHash);i;i=sqliteHashNext(i)){
    Index *pIdx = sqliteHashData(i);
    sqlite3DefaultRowEst(pIdx);
#ifdef SQLITE_ENABLE_STAT3
    sqlite3DeleteIndexSamples(db, pIdx);
    pIdx->aSample = 0;
#endif
  }

  /* Check to make sure the sqlite_stat1 table exists */
  sInfo.db = db;
................................................................................
    rc = SQLITE_NOMEM;
  }else{
    rc = sqlite3_exec(db, zSql, analysisLoader, &sInfo, 0);
    sqlite3DbFree(db, zSql);
  }


  /* Load the statistics from the sqlite_stat3 table. */
#ifdef SQLITE_ENABLE_STAT3
  if( rc==SQLITE_OK ){
    int lookasideEnabled = db->lookaside.bEnabled;
    db->lookaside.bEnabled = 0;
    rc = loadStat3(db, sInfo.zDatabase);
    db->lookaside.bEnabled = lookasideEnabled;
  }
#endif

  if( rc==SQLITE_NOMEM ){
    db->mallocFailed = 1;
  }
................................................................................
        "attached databases must use the same text encoding as main database");
      rc = SQLITE_ERROR;
    }
    pPager = sqlite3BtreePager(aNew->pBt);
    sqlite3PagerLockingMode(pPager, db->dfltLockMode);
    sqlite3BtreeSecureDelete(aNew->pBt,
                             sqlite3BtreeSecureDelete(db->aDb[0].pBt,-1) );

    sqlite3BtreeSetPagerFlags(aNew->pBt, 3 | (db->flags & PAGER_FLAGS_MASK));

  }
  aNew->safety_level = 3;
  aNew->zName = sqlite3DbStrDup(db, zName);
  if( rc==SQLITE_OK && aNew->zName==0 ){
    rc = SQLITE_NOMEM;
  }

................................................................................
** Called by the parser to compile a DETACH statement.
**
**     DETACH pDbname
*/
SQLITE_PRIVATE void sqlite3Detach(Parse *pParse, Expr *pDbname){
  static const FuncDef detach_func = {
    1,                /* nArg */
    SQLITE_UTF8,      /* iPrefEnc */
    0,                /* flags */
    0,                /* pUserData */
    0,                /* pNext */
    detachFunc,       /* xFunc */
    0,                /* xStep */
    0,                /* xFinalize */
    "sqlite_detach",  /* zName */
    0,                /* pHash */
................................................................................
** Called by the parser to compile an ATTACH statement.
**
**     ATTACH p AS pDbname KEY pKey
*/
SQLITE_PRIVATE void sqlite3Attach(Parse *pParse, Expr *p, Expr *pDbname, Expr *pKey){
  static const FuncDef attach_func = {
    3,                /* nArg */
    SQLITE_UTF8,      /* iPrefEnc */
    0,                /* flags */
    0,                /* pUserData */
    0,                /* pNext */
    attachFunc,       /* xFunc */
    0,                /* xStep */
    0,                /* xFinalize */
    "sqlite_attach",  /* zName */
    0,                /* pHash */
................................................................................
  codeAttach(pParse, SQLITE_ATTACH, &attach_func, p, p, pDbname, pKey);
}
#endif /* SQLITE_OMIT_ATTACH */

/*
** Initialize a DbFixer structure.  This routine must be called prior
** to passing the structure to one of the sqliteFixAAAA() routines below.
**
** The return value indicates whether or not fixation is required.  TRUE
** means we do need to fix the database references, FALSE means we do not.
*/
SQLITE_PRIVATE int sqlite3FixInit(
  DbFixer *pFix,      /* The fixer to be initialized */
  Parse *pParse,      /* Error messages will be written here */
  int iDb,            /* This is the database that must be used */
  const char *zType,  /* "view", "trigger", or "index" */
  const Token *pName  /* Name of the view, trigger, or index */
){
  sqlite3 *db;

  if( NEVER(iDb<0) || iDb==1 ) return 0;
  db = pParse->db;
  assert( db->nDb>iDb );
  pFix->pParse = pParse;
  pFix->zDb = db->aDb[iDb].zName;
  pFix->pSchema = db->aDb[iDb].pSchema;
  pFix->zType = zType;
  pFix->pName = pName;
  return 1;
}

/*
** The following set of routines walk through the parse tree and assign
** a specific database to all table references where the database name
** was left unspecified in the original SQL statement.  The pFix structure
** must have been initialized by a prior call to sqlite3FixInit().
................................................................................
  int i;
  const char *zDb;
  struct SrcList_item *pItem;

  if( NEVER(pList==0) ) return 0;
  zDb = pFix->zDb;
  for(i=0, pItem=pList->a; i<pList->nSrc; i++, pItem++){

    if( pItem->zDatabase && sqlite3StrICmp(pItem->zDatabase, zDb) ){
      sqlite3ErrorMsg(pFix->pParse,
         "%s %T cannot reference objects in database %s",
         pFix->zType, pFix->pName, pItem->zDatabase);
      return 1;
    }
    sqlite3DbFree(pFix->pParse->db, pItem->zDatabase);
    pItem->zDatabase = 0;
    pItem->pSchema = pFix->pSchema;

#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_TRIGGER)
    if( sqlite3FixSelect(pFix, pItem->pSelect) ) return 1;
    if( sqlite3FixExpr(pFix, pItem->pOn) ) return 1;
#endif
  }
  return 0;
}
................................................................................
      return 1;
    }
    if( sqlite3FixSrcList(pFix, pSelect->pSrc) ){
      return 1;
    }
    if( sqlite3FixExpr(pFix, pSelect->pWhere) ){
      return 1;



    }
    if( sqlite3FixExpr(pFix, pSelect->pHaving) ){
      return 1;









    }
    pSelect = pSelect->pPrior;
  }
  return 0;
}
SQLITE_PRIVATE int sqlite3FixExpr(
  DbFixer *pFix,     /* Context of the fixation */
  Expr *pExpr        /* The expression to be fixed to one database */
){
  while( pExpr ){








    if( ExprHasAnyProperty(pExpr, EP_TokenOnly) ) break;
    if( ExprHasProperty(pExpr, EP_xIsSelect) ){
      if( sqlite3FixSelect(pFix, pExpr->x.pSelect) ) return 1;
    }else{
      if( sqlite3FixExprList(pFix, pExpr->x.pList) ) return 1;
    }
    if( sqlite3FixExpr(pFix, pExpr->pRight) ){
      return 1;
................................................................................
    pParse->nErr++;
    goto begin_table_error;
  }
  pTable->zName = zName;
  pTable->iPKey = -1;
  pTable->pSchema = db->aDb[iDb].pSchema;
  pTable->nRef = 1;
  pTable->nRowEst = 1000000;
  assert( pParse->pNewTable==0 );
  pParse->pNewTable = pTable;

  /* If this is the magic sqlite_sequence table used by autoincrement,
  ** then record a pointer to this table in the main database structure
  ** so that INSERT can find the table easily.
  */
................................................................................
  pCol->zName = z;
 
  /* If there is no type specified, columns have the default affinity
  ** 'NONE'. If there is a type specified, then sqlite3AddColumnType() will
  ** be called next to set pCol->affinity correctly.
  */
  pCol->affinity = SQLITE_AFF_NONE;

  p->nCol++;
}

/*
** This routine is called by the parser while in the middle of
** parsing a CREATE TABLE statement.  A "NOT NULL" constraint has
** been seen on a column.  This routine sets the notNull flag on
................................................................................
** 'REAL'        | SQLITE_AFF_REAL
** 'FLOA'        | SQLITE_AFF_REAL
** 'DOUB'        | SQLITE_AFF_REAL
**
** If none of the substrings in the above table are found,
** SQLITE_AFF_NUMERIC is returned.
*/
SQLITE_PRIVATE char sqlite3AffinityType(const char *zIn){
  u32 h = 0;
  char aff = SQLITE_AFF_NUMERIC;



  if( zIn ) while( zIn[0] ){
    h = (h<<8) + sqlite3UpperToLower[(*zIn)&0xff];
    zIn++;
    if( h==(('c'<<24)+('h'<<16)+('a'<<8)+'r') ){             /* CHAR */
      aff = SQLITE_AFF_TEXT; 

    }else if( h==(('c'<<24)+('l'<<16)+('o'<<8)+'b') ){       /* CLOB */
      aff = SQLITE_AFF_TEXT;
    }else if( h==(('t'<<24)+('e'<<16)+('x'<<8)+'t') ){       /* TEXT */
      aff = SQLITE_AFF_TEXT;
    }else if( h==(('b'<<24)+('l'<<16)+('o'<<8)+'b')          /* BLOB */
        && (aff==SQLITE_AFF_NUMERIC || aff==SQLITE_AFF_REAL) ){
      aff = SQLITE_AFF_NONE;

#ifndef SQLITE_OMIT_FLOATING_POINT
    }else if( h==(('r'<<24)+('e'<<16)+('a'<<8)+'l')          /* REAL */
        && aff==SQLITE_AFF_NUMERIC ){
      aff = SQLITE_AFF_REAL;
    }else if( h==(('f'<<24)+('l'<<16)+('o'<<8)+'a')          /* FLOA */
        && aff==SQLITE_AFF_NUMERIC ){
      aff = SQLITE_AFF_REAL;
................................................................................
#endif
    }else if( (h&0x00FFFFFF)==(('i'<<16)+('n'<<8)+'t') ){    /* INT */
      aff = SQLITE_AFF_INTEGER;
      break;
    }
  }























  return aff;
}

/*
** This routine is called by the parser while in the middle of
** parsing a CREATE TABLE statement.  The pFirst token is the first
** token in the sequence of tokens that describe the type of the
................................................................................
  Column *pCol;

  p = pParse->pNewTable;
  if( p==0 || NEVER(p->nCol<1) ) return;
  pCol = &p->aCol[p->nCol-1];
  assert( pCol->zType==0 );
  pCol->zType = sqlite3NameFromToken(pParse->db, pType);
  pCol->affinity = sqlite3AffinityType(pCol->zType);
}

/*
** The expression is the default value for the most recently added column
** of the table currently under construction.
**
** Default value expressions must be constant.  Raise an exception if this
................................................................................
    testcase( pCol->affinity==SQLITE_AFF_NUMERIC );
    testcase( pCol->affinity==SQLITE_AFF_INTEGER );
    testcase( pCol->affinity==SQLITE_AFF_REAL );
    
    zType = azType[pCol->affinity - SQLITE_AFF_TEXT];
    len = sqlite3Strlen30(zType);
    assert( pCol->affinity==SQLITE_AFF_NONE 
            || pCol->affinity==sqlite3AffinityType(zType) );
    memcpy(&zStmt[k], zType, len);
    k += len;
    assert( k<=n );
  }
  sqlite3_snprintf(n-k, &zStmt[k], "%s", zEnd);
  return zStmt;
}





























/*
** This routine is called to report the final ")" that terminates
** a CREATE TABLE statement.
**
** The table structure that other action routines have been building
** is added to the internal hash tables, assuming no errors have
................................................................................
*/
SQLITE_PRIVATE void sqlite3EndTable(
  Parse *pParse,          /* Parse context */
  Token *pCons,           /* The ',' token after the last column defn. */
  Token *pEnd,            /* The final ')' token in the CREATE TABLE */
  Select *pSelect         /* Select from a "CREATE ... AS SELECT" */
){
  Table *p;
  sqlite3 *db = pParse->db;
  int iDb;


  if( (pEnd==0 && pSelect==0) || db->mallocFailed ){
    return;
  }
  p = pParse->pNewTable;
  if( p==0 ) return;

................................................................................
#ifndef SQLITE_OMIT_CHECK
  /* Resolve names in all CHECK constraint expressions.
  */
  if( p->pCheck ){
    sqlite3ResolveSelfReference(pParse, p, NC_IsCheck, 0, p->pCheck);
  }
#endif /* !defined(SQLITE_OMIT_CHECK) */







  /* If the db->init.busy is 1 it means we are reading the SQL off the
  ** "sqlite_master" or "sqlite_temp_master" table on the disk.
  ** So do not write to the disk again.  Extract the root page number
  ** for the table from the db->init.newTnum field.  (The page number
  ** should have been put there by the sqliteOpenCb routine.)
  */
................................................................................
  p = pParse->pNewTable;
  if( p==0 || pParse->nErr ){
    sqlite3SelectDelete(db, pSelect);
    return;
  }
  sqlite3TwoPartName(pParse, pName1, pName2, &pName);
  iDb = sqlite3SchemaToIndex(db, p->pSchema);
  if( sqlite3FixInit(&sFix, pParse, iDb, "view", pName)
    && sqlite3FixSelect(&sFix, pSelect)
  ){
    sqlite3SelectDelete(db, pSelect);
    return;
  }

  /* Make a copy of the entire SELECT statement that defines the view.
  ** This will force all the Expr.token.z values to be dynamically
  ** allocated rather than point to the input string - which means that
................................................................................
  Parse *pParse,         /* The parsing context */
  int iDb,               /* The database number */
  const char *zType,     /* "idx" or "tbl" */
  const char *zName      /* Name of index or table */
){
  int i;
  const char *zDbName = pParse->db->aDb[iDb].zName;
  for(i=1; i<=3; i++){
    char zTab[24];
    sqlite3_snprintf(sizeof(zTab),zTab,"sqlite_stat%d",i);
    if( sqlite3FindTable(pParse->db, zTab, zDbName) ){
      sqlite3NestedParse(pParse,
        "DELETE FROM %Q.%s WHERE %s=%Q",
        zDbName, zTab, zType, zName
      );
................................................................................
  DbFixer sFix;        /* For assigning database names to pTable */
  int sortOrderMask;   /* 1 to honor DESC in index.  0 to ignore. */
  sqlite3 *db = pParse->db;
  Db *pDb;             /* The specific table containing the indexed database */
  int iDb;             /* Index of the database that is being written */
  Token *pName = 0;    /* Unqualified name of the index to create */
  struct ExprList_item *pListItem; /* For looping over pList */
  int nCol;

  int nExtra = 0;
  char *zExtra;


  assert( pParse->nErr==0 );      /* Never called with prior errors */
  if( db->mallocFailed || IN_DECLARE_VTAB ){
    goto exit_create_index;
  }
  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
    goto exit_create_index;
................................................................................
      pTab = sqlite3SrcListLookup(pParse, pTblName);
      if( pName2->n==0 && pTab && pTab->pSchema==db->aDb[1].pSchema ){
        iDb = 1;
      }
    }
#endif

    if( sqlite3FixInit(&sFix, pParse, iDb, "index", pName) &&
        sqlite3FixSrcList(&sFix, pTblName)
    ){
      /* Because the parser constructs pTblName from a single identifier,
      ** sqlite3FixSrcList can never fail. */
      assert(0);
    }
    pTab = sqlite3LocateTableItem(pParse, 0, &pTblName->a[0]);
    assert( db->mallocFailed==0 || pTab==0 );
    if( pTab==0 ) goto exit_create_index;
................................................................................
  ** more than once within the same index.  Only the first instance of
  ** the column will ever be used by the optimizer.  Note that using the
  ** same column more than once cannot be an error because that would 
  ** break backwards compatibility - it needs to be a warning.
  */
  for(i=0, pListItem=pList->a; i<pList->nExpr; i++, pListItem++){
    const char *zColName = pListItem->zName;
    Column *pTabCol;
    int requestedSortOrder;
    char *zColl;                   /* Collation sequence name */

    for(j=0, pTabCol=pTab->aCol; j<pTab->nCol; j++, pTabCol++){
      if( sqlite3StrICmp(zColName, pTabCol->zName)==0 ) break;
    }
    if( j>=pTab->nCol ){
................................................................................
    }
    pIndex->azColl[i] = zColl;
    requestedSortOrder = pListItem->sortOrder & sortOrderMask;
    pIndex->aSortOrder[i] = (u8)requestedSortOrder;
    if( pTab->aCol[j].notNull==0 ) pIndex->uniqNotNull = 0;
  }
  sqlite3DefaultRowEst(pIndex);


  if( pTab==pParse->pNewTable ){
    /* This routine has been called to create an automatic index as a
    ** result of a PRIMARY KEY or UNIQUE clause on a column definition, or
    ** a PRIMARY KEY or UNIQUE clause following the column definitions.
    ** i.e. one of:
    **
................................................................................
  if( p->nArg==nArg ){
    match = 4;
  }else{
    match = 1;
  }

  /* Bonus points if the text encoding matches */
  if( enc==p->iPrefEnc ){
    match += 2;  /* Exact encoding match */
  }else if( (enc & p->iPrefEnc & 2)!=0 ){
    match += 1;  /* Both are UTF16, but with different byte orders */
  }

  return match;
}

/*
................................................................................
  ** exact match for the name, number of arguments and encoding, then add a
  ** new entry to the hash table and return it.
  */
  if( createFlag && bestScore<FUNC_PERFECT_MATCH && 
      (pBest = sqlite3DbMallocZero(db, sizeof(*pBest)+nName+1))!=0 ){
    pBest->zName = (char *)&pBest[1];
    pBest->nArg = (u16)nArg;
    pBest->iPrefEnc = enc;
    memcpy(pBest->zName, zName, nName);
    pBest->zName[nName] = 0;
    sqlite3FuncDefInsert(&db->aFunc, pBest);
  }

  if( pBest && (pBest->xStep || pBest->xFunc || createFlag) ){
    return pBest;
................................................................................
  ** It is easier just to erase the whole table. Prior to version 3.6.5,
  ** this optimization caused the row change count (the value returned by 
  ** API function sqlite3_count_changes) to be set incorrectly.  */
  if( rcauth==SQLITE_OK && pWhere==0 && !pTrigger && !IsVirtual(pTab) 
   && 0==sqlite3FkRequired(pParse, pTab, 0, 0)
  ){
    assert( !isView );

    sqlite3VdbeAddOp4(v, OP_Clear, pTab->tnum, iDb, memCnt,
                      pTab->zName, P4_STATIC);
    for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
      assert( pIdx->pSchema==pTab->pSchema );
      sqlite3VdbeAddOp2(v, OP_Clear, pIdx->tnum, iDb);
    }
  }else
................................................................................
    ** being deleted. Do not attempt to delete the row a second time, and 
    ** do not fire AFTER triggers.  */
    sqlite3VdbeAddOp3(v, OP_NotExists, iCur, iLabel, iRowid);

    /* Do FK processing. This call checks that any FK constraints that
    ** refer to this table (i.e. constraints attached to other tables) 
    ** are not violated by deleting this row.  */
    sqlite3FkCheck(pParse, pTab, iOld, 0);
  }

  /* Delete the index and table entries. Skip this step if pTab is really
  ** a view (in which case the only effect of the DELETE statement is to
  ** fire the INSTEAD OF triggers).  */ 
  if( pTab->pSelect==0 ){
    sqlite3GenerateRowIndexDelete(pParse, pTab, iCur, 0);
................................................................................
      sqlite3VdbeChangeP4(v, -1, pTab->zName, P4_TRANSIENT);
    }
  }

  /* Do any ON CASCADE, SET NULL or SET DEFAULT operations required to
  ** handle rows (possibly in other tables) that refer via a foreign key
  ** to the row just deleted. */ 
  sqlite3FkActions(pParse, pTab, 0, iOld);

  /* Invoke AFTER DELETE trigger programs. */
  sqlite3CodeRowTrigger(pParse, pTrigger, 
      TK_DELETE, 0, TRIGGER_AFTER, pTab, iOld, onconf, iLabel
  );

  /* Jump here if the row had already been deleted before any BEFORE
................................................................................
      }
      sqlite3_result_text(context, z1, n, sqlite3_free);
    }
  }
}

/*
** The COALESCE() and IFNULL() functions are implemented as VDBE code so
** that unused argument values do not have to be computed.  However, we
** still need some kind of function implementation for this routines in
** the function table.  That function implementation will never be called
** so it doesn't matter what the implementation is.  We might as well use
** the "version()" function as a substitute.
*/
#define ifnullFunc versionFunc   /* Substitute function - never called */

/*
** Implementation of random().  Return a random integer.  
*/
static void randomFunc(
  sqlite3_context *context,
  int NotUsed,
................................................................................
** For LIKE and GLOB matching on EBCDIC machines, assume that every
** character is exactly one byte in size.  Also, all characters are
** able to participate in upper-case-to-lower-case mappings in EBCDIC
** whereas only characters less than 0x80 do in ASCII.
*/
#if defined(SQLITE_EBCDIC)
# define sqlite3Utf8Read(A)    (*((*A)++))
# define GlogUpperToLower(A)   A = sqlite3UpperToLower[A]
#else
# define GlogUpperToLower(A)   if( !((A)&~0x7f) ){ A = sqlite3UpperToLower[A]; }
#endif

static const struct compareInfo globInfo = { '*', '?', '[', 0 };
/* The correct SQL-92 behavior is for the LIKE operator to ignore
** case.  Thus  'a' LIKE 'A' would be true. */
static const struct compareInfo likeInfoNorm = { '%', '_',   0, 1 };
/* If SQLITE_CASE_SENSITIVE_LIKE is defined, then the LIKE operator
................................................................................
        while( *zString && patternCompare(&zPattern[-1],zString,pInfo,esc)==0 ){
          SQLITE_SKIP_UTF8(zString);
        }
        return *zString!=0;
      }
      while( (c2 = sqlite3Utf8Read(&zString))!=0 ){
        if( noCase ){
          GlogUpperToLower(c2);
          GlogUpperToLower(c);
          while( c2 != 0 && c2 != c ){
            c2 = sqlite3Utf8Read(&zString);
            GlogUpperToLower(c2);
          }
        }else{
          while( c2 != 0 && c2 != c ){
            c2 = sqlite3Utf8Read(&zString);
          }
        }
        if( c2==0 ) return 0;
................................................................................
        return 0;
      }
    }else if( esc==c && !prevEscape ){
      prevEscape = 1;
    }else{
      c2 = sqlite3Utf8Read(&zString);
      if( noCase ){
        GlogUpperToLower(c);
        GlogUpperToLower(c2);
      }
      if( c!=c2 ){
        return 0;
      }
      prevEscape = 0;
    }
  }
................................................................................
** Set the LIKEOPT flag on the 2-argument function with the given name.
*/
static void setLikeOptFlag(sqlite3 *db, const char *zName, u8 flagVal){
  FuncDef *pDef;
  pDef = sqlite3FindFunction(db, zName, sqlite3Strlen30(zName),
                             2, SQLITE_UTF8, 0);
  if( ALWAYS(pDef) ){
    pDef->flags = flagVal;
  }
}

/*
** Register the built-in LIKE and GLOB functions.  The caseSensitive
** parameter determines whether or not the LIKE operator is case
** sensitive.  GLOB is always case sensitive.
................................................................................
  ){
    return 0;
  }
  assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
  pDef = sqlite3FindFunction(db, pExpr->u.zToken, 
                             sqlite3Strlen30(pExpr->u.zToken),
                             2, SQLITE_UTF8, 0);
  if( NEVER(pDef==0) || (pDef->flags & SQLITE_FUNC_LIKE)==0 ){
    return 0;
  }

  /* The memcpy() statement assumes that the wildcard characters are
  ** the first three statements in the compareInfo structure.  The
  ** asserts() that follow verify that assumption
  */
  memcpy(aWc, pDef->pUserData, 3);
  assert( (char*)&likeInfoAlt == (char*)&likeInfoAlt.matchAll );
  assert( &((char*)&likeInfoAlt)[1] == (char*)&likeInfoAlt.matchOne );
  assert( &((char*)&likeInfoAlt)[2] == (char*)&likeInfoAlt.matchSet );
  *pIsNocase = (pDef->flags & SQLITE_FUNC_CASE)==0;
  return 1;
}

/*
** All all of the FuncDef structures in the aBuiltinFunc[] array above
** to the global function hash table.  This occurs at start-time (as
** a consequence of calling sqlite3_initialize()).
................................................................................
    FUNCTION(round,              1, 0, 0, roundFunc        ),
    FUNCTION(round,              2, 0, 0, roundFunc        ),
#endif
    FUNCTION(upper,              1, 0, 0, upperFunc        ),
    FUNCTION(lower,              1, 0, 0, lowerFunc        ),
    FUNCTION(coalesce,           1, 0, 0, 0                ),
    FUNCTION(coalesce,           0, 0, 0, 0                ),
    FUNCTION2(coalesce,         -1, 0, 0, ifnullFunc,  SQLITE_FUNC_COALESCE),
    FUNCTION(hex,                1, 0, 0, hexFunc          ),
    FUNCTION2(ifnull,            2, 0, 0, ifnullFunc,  SQLITE_FUNC_COALESCE),


    FUNCTION(random,             0, 0, 0, randomFunc       ),
    FUNCTION(randomblob,         1, 0, 0, randomBlob       ),
    FUNCTION(nullif,             2, 0, 1, nullifFunc       ),
    FUNCTION(sqlite_version,     0, 0, 0, versionFunc      ),
    FUNCTION(sqlite_source_id,   0, 0, 0, sourceidFunc     ),
    FUNCTION(sqlite_log,         2, 0, 0, errlogFunc       ),
#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
................................................................................
    FUNCTION(load_extension,     1, 0, 0, loadExt          ),
    FUNCTION(load_extension,     2, 0, 0, loadExt          ),
  #endif
    AGGREGATE(sum,               1, 0, 0, sumStep,         sumFinalize    ),
    AGGREGATE(total,             1, 0, 0, sumStep,         totalFinalize    ),
    AGGREGATE(avg,               1, 0, 0, sumStep,         avgFinalize    ),
 /* AGGREGATE(count,             0, 0, 0, countStep,       countFinalize  ), */
    {0,SQLITE_UTF8,SQLITE_FUNC_COUNT,0,0,0,countStep,countFinalize,"count",0,0},
    AGGREGATE(count,             1, 0, 0, countStep,       countFinalize  ),
    AGGREGATE(group_concat,      1, 0, 0, groupConcatStep, groupConcatFinalize),
    AGGREGATE(group_concat,      2, 0, 0, groupConcatStep, groupConcatFinalize),
  
    LIKEFUNC(glob, 2, &globInfo, SQLITE_FUNC_LIKE|SQLITE_FUNC_CASE),
  #ifdef SQLITE_CASE_SENSITIVE_LIKE
    LIKEFUNC(like, 2, &likeInfoAlt, SQLITE_FUNC_LIKE|SQLITE_FUNC_CASE),
................................................................................

  for(i=0; i<ArraySize(aBuiltinFunc); i++){
    sqlite3FuncDefInsert(pHash, &aFunc[i]);
  }
  sqlite3RegisterDateTimeFunctions();
#ifndef SQLITE_OMIT_ALTERTABLE
  sqlite3AlterFunctions();



#endif
}

/************** End of func.c ************************************************/
/************** Begin file fkey.c ********************************************/
/*
**
................................................................................
      /* Search for a deferred foreign key constraint for which this table
      ** is the child table. If one cannot be found, return without 
      ** generating any VDBE code. If one can be found, then jump over
      ** the entire DELETE if there are no outstanding deferred constraints
      ** when this statement is run.  */
      FKey *p;
      for(p=pTab->pFKey; p; p=p->pNextFrom){
        if( p->isDeferred ) break;
      }
      if( !p ) return;
      iSkip = sqlite3VdbeMakeLabel(v);
      sqlite3VdbeAddOp2(v, OP_FkIfZero, 1, iSkip);
    }

    pParse->disableTriggers = 1;
    sqlite3DeleteFrom(pParse, sqlite3SrcListDup(db, pName, 0), 0);
    pParse->disableTriggers = 0;

    /* If the DELETE has generated immediate foreign key constraint 
    ** violations, halt the VDBE and return an error at this point, before
    ** any modifications to the schema are made. This is because statement
    ** transactions are not able to rollback schema changes.  */






    sqlite3VdbeAddOp2(v, OP_FkIfZero, 0, sqlite3VdbeCurrentAddr(v)+2);
    sqlite3HaltConstraint(pParse, SQLITE_CONSTRAINT_FOREIGNKEY,
        OE_Abort, "foreign key constraint failed", P4_STATIC
    );


    if( iSkip ){
      sqlite3VdbeResolveLabel(v, iSkip);
    }
  }
}

































































/*
** This function is called when inserting, deleting or updating a row of
** table pTab to generate VDBE code to perform foreign key constraint 
** processing for the operation.
**
** For a DELETE operation, parameter regOld is passed the index of the
** first register in an array of (pTab->nCol+1) registers containing the
................................................................................
** described for DELETE. Then again after the original record is deleted
** but before the new record is inserted using the INSERT convention. 
*/
SQLITE_PRIVATE void sqlite3FkCheck(
  Parse *pParse,                  /* Parse context */
  Table *pTab,                    /* Row is being deleted from this table */ 
  int regOld,                     /* Previous row data is stored here */
  int regNew                      /* New row data is stored here */


){
  sqlite3 *db = pParse->db;       /* Database handle */
  FKey *pFKey;                    /* Used to iterate through FKs */
  int iDb;                        /* Index of database containing pTab */
  const char *zDb;                /* Name of database containing pTab */
  int isIgnoreErrors = pParse->disableTriggers;

................................................................................
    Table *pTo;                   /* Parent table of foreign key pFKey */
    Index *pIdx = 0;              /* Index on key columns in pTo */
    int *aiFree = 0;
    int *aiCol;
    int iCol;
    int i;
    int isIgnore = 0;








    /* Find the parent table of this foreign key. Also find a unique index 
    ** on the parent key columns in the parent table. If either of these 
    ** schema items cannot be located, set an error in pParse and return 
    ** early.  */
    if( pParse->disableTriggers ){
      pTo = sqlite3FindTable(db, pFKey->zTo, zDb);
................................................................................
  }

  /* Loop through all the foreign key constraints that refer to this table */
  for(pFKey = sqlite3FkReferences(pTab); pFKey; pFKey=pFKey->pNextTo){
    Index *pIdx = 0;              /* Foreign key index for pFKey */
    SrcList *pSrc;
    int *aiCol = 0;





    if( !pFKey->isDeferred && !(db->flags & SQLITE_DeferFKs) 
     && !pParse->pToplevel && !pParse->isMultiWrite 
    ){
      assert( regOld==0 && regNew!=0 );
      /* Inserting a single row into a parent table cannot cause an immediate
      ** foreign key violation. So do nothing in this case.  */
................................................................................
      if( pIdx ){
        for(i=0; i<pIdx->nColumn; i++) mask |= COLUMN_MASK(pIdx->aiColumn[i]);
      }
    }
  }
  return mask;
}


/*
** This function is called before generating code to update or delete a 
** row contained in table pTab. If the operation is a DELETE, then
** parameter aChange is passed a NULL value. For an UPDATE, aChange points
** to an array of size N, where N is the number of columns in table pTab.
** If the i'th column is not modified by the UPDATE, then the corresponding 
................................................................................
      /* A DELETE operation. Foreign key processing is required if the 
      ** table in question is either the child or parent table for any 
      ** foreign key constraint.  */
      return (sqlite3FkReferences(pTab) || pTab->pFKey);
    }else{
      /* This is an UPDATE. Foreign key processing is only required if the
      ** operation modifies one or more child or parent key columns. */
      int i;
      FKey *p;

      /* Check if any child key columns are being modified. */
      for(p=pTab->pFKey; p; p=p->pNextFrom){
        for(i=0; i<p->nCol; i++){
          int iChildKey = p->aCol[i].iFrom;
          if( aChange[iChildKey]>=0 ) return 1;
          if( iChildKey==pTab->iPKey && chngRowid ) return 1;
        }
      }

      /* Check if any parent key columns are being modified. */
      for(p=sqlite3FkReferences(pTab); p; p=p->pNextTo){
        for(i=0; i<p->nCol; i++){
          char *zKey = p->aCol[i].zCol;
          int iKey;
          for(iKey=0; iKey<pTab->nCol; iKey++){
            Column *pCol = &pTab->aCol[iKey];
            if( (zKey ? !sqlite3StrICmp(pCol->zName, zKey)
                      : (pCol->colFlags & COLFLAG_PRIMKEY)!=0) ){
              if( aChange[iKey]>=0 ) return 1;
              if( iKey==pTab->iPKey && chngRowid ) return 1;
            }
          }
        }
      }
    }
  }
  return 0;
}

/*
................................................................................
** This function is called when deleting or updating a row to implement
** any required CASCADE, SET NULL or SET DEFAULT actions.
*/
SQLITE_PRIVATE void sqlite3FkActions(
  Parse *pParse,                  /* Parse context */
  Table *pTab,                    /* Table being updated or deleted from */
  ExprList *pChanges,             /* Change-list for UPDATE, NULL for DELETE */
  int regOld                      /* Address of array containing old row */


){
  /* If foreign-key support is enabled, iterate through all FKs that 
  ** refer to table pTab. If there is an action associated with the FK 
  ** for this operation (either update or delete), invoke the associated 
  ** trigger sub-program.  */
  if( pParse->db->flags&SQLITE_ForeignKeys ){
    FKey *pFKey;                  /* Iterator variable */
    for(pFKey = sqlite3FkReferences(pTab); pFKey; pFKey=pFKey->pNextTo){

      Trigger *pAction = fkActionTrigger(pParse, pTab, pFKey, pChanges);
      if( pAction ){
        sqlite3CodeRowTriggerDirect(pParse, pAction, pTab, regOld, OE_Abort, 0);

      }
    }
  }
}

#endif /* ifndef SQLITE_OMIT_TRIGGER */

................................................................................
    }else
#endif
    {
      int isReplace;    /* Set to true if constraints may cause a replace */
      sqlite3GenerateConstraintChecks(pParse, pTab, baseCur, regIns, aRegIdx,
          keyColumn>=0, 0, onError, endOfLoop, &isReplace
      );
      sqlite3FkCheck(pParse, pTab, 0, regIns);
      sqlite3CompleteInsertion(
          pParse, pTab, baseCur, regIns, aRegIdx, 0, appendFlag, isReplace==0
      );
    }
  }

  /* Update the count of rows that are inserted
................................................................................
    pKey = sqlite3IndexKeyinfo(pParse, pSrcIdx);
    sqlite3VdbeAddOp4(v, OP_OpenRead, iSrc, pSrcIdx->tnum, iDbSrc,
                      (char*)pKey, P4_KEYINFO_HANDOFF);
    VdbeComment((v, "%s", pSrcIdx->zName));
    pKey = sqlite3IndexKeyinfo(pParse, pDestIdx);
    sqlite3VdbeAddOp4(v, OP_OpenWrite, iDest, pDestIdx->tnum, iDbDest,
                      (char*)pKey, P4_KEYINFO_HANDOFF);

    VdbeComment((v, "%s", pDestIdx->zName));
    addr1 = sqlite3VdbeAddOp2(v, OP_Rewind, iSrc, 0);
    sqlite3VdbeAddOp2(v, OP_RowKey, iSrc, regData);
    sqlite3VdbeAddOp3(v, OP_IdxInsert, iDest, regData, 1);
    sqlite3VdbeAddOp2(v, OP_Next, iSrc, addr1+1);
    sqlite3VdbeJumpHere(v, addr1);
  }
................................................................................
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains code used to implement the PRAGMA command.
*/



































































































































































































































































































































































































































/*
** Interpret the given string as a safety level.  Return 0 for OFF,
** 1 for ON or NORMAL and 2 for FULL.  Return 1 for an empty or 
** unrecognized string argument.  The FULL option is disallowed
** if the omitFull parameter it 1.
**
** Note that the values returned are one less that the values that
................................................................................
        sqlite3BtreeSetPagerFlags(pDb->pBt,
                 pDb->safety_level | (db->flags & PAGER_FLAGS_MASK) );
      }
      pDb++;
    }
  }
}
#endif


#ifndef SQLITE_OMIT_FLAG_PRAGMAS
/*
** Check to see if zRight and zLeft refer to a pragma that queries
** or changes one of the flags in db->flags.  Return 1 if so and 0 if not.
** Also, implement the pragma.
*/
static int flagPragma(Parse *pParse, const char *zLeft, const char *zRight){
  static const struct sPragmaType {
    const char *zName;  /* Name of the pragma */
    int mask;           /* Mask for the db->flags value */
  } aPragma[] = {
    { "full_column_names",        SQLITE_FullColNames  },
    { "short_column_names",       SQLITE_ShortColNames },
    { "count_changes",            SQLITE_CountRows     },
    { "empty_result_callbacks",   SQLITE_NullCallback  },
    { "legacy_file_format",       SQLITE_LegacyFileFmt },
    { "fullfsync",                SQLITE_FullFSync     },
    { "checkpoint_fullfsync",     SQLITE_CkptFullFSync },
    { "cache_spill",              SQLITE_CacheSpill    },
    { "reverse_unordered_selects", SQLITE_ReverseOrder  },
    { "query_only",               SQLITE_QueryOnly     },
#ifndef SQLITE_OMIT_AUTOMATIC_INDEX
    { "automatic_index",          SQLITE_AutoIndex     },

#endif
#ifdef SQLITE_DEBUG
    { "sql_trace",                SQLITE_SqlTrace      },
    { "vdbe_listing",             SQLITE_VdbeListing   },
    { "vdbe_trace",               SQLITE_VdbeTrace     },
    { "vdbe_addoptrace",          SQLITE_VdbeAddopTrace},
    { "vdbe_debug",    SQLITE_SqlTrace | SQLITE_VdbeListing
                               | SQLITE_VdbeTrace      },
#endif
#ifndef SQLITE_OMIT_CHECK
    { "ignore_check_constraints", SQLITE_IgnoreChecks  },
#endif
    /* The following is VERY experimental */
    { "writable_schema",          SQLITE_WriteSchema|SQLITE_RecoveryMode },

    /* TODO: Maybe it shouldn't be possible to change the ReadUncommitted
    ** flag if there are any active statements. */
    { "read_uncommitted",         SQLITE_ReadUncommitted },
    { "recursive_triggers",       SQLITE_RecTriggers   },

    /* This flag may only be set if both foreign-key and trigger support
    ** are present in the build.  */
#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
    { "foreign_keys",             SQLITE_ForeignKeys   },
    { "defer_foreign_keys",       SQLITE_DeferFKs      },
#endif
  };
  int i;
  const struct sPragmaType *p;
  for(i=0, p=aPragma; i<ArraySize(aPragma); i++, p++){
    if( sqlite3StrICmp(zLeft, p->zName)==0 ){
      sqlite3 *db = pParse->db;
      Vdbe *v;
      v = sqlite3GetVdbe(pParse);
      assert( v!=0 );  /* Already allocated by sqlite3Pragma() */
      if( ALWAYS(v) ){
        if( zRight==0 ){
          returnSingleInt(pParse, p->zName, (db->flags & p->mask)!=0 );
        }else{
          int mask = p->mask;          /* Mask of bits to set or clear. */
          if( db->autoCommit==0 ){
            /* Foreign key support may not be enabled or disabled while not
            ** in auto-commit mode.  */
            mask &= ~(SQLITE_ForeignKeys);
          }

          if( sqlite3GetBoolean(zRight, 0) ){
            db->flags |= mask;
          }else{
            db->flags &= ~mask;
            if( mask==SQLITE_DeferFKs ) db->nDeferredImmCons = 0;
          }

          /* Many of the flag-pragmas modify the code generated by the SQL 
          ** compiler (eg. count_changes). So add an opcode to expire all
          ** compiled SQL statements after modifying a pragma value.
          */
          sqlite3VdbeAddOp2(v, OP_Expire, 0, 0);
        }
      }

      return 1;
    }
  }
  return 0;
}
#endif /* SQLITE_OMIT_FLAG_PRAGMAS */

/*
** Return a human-readable name for a constraint resolution action.
*/
#ifndef SQLITE_OMIT_FOREIGN_KEY
static const char *actionName(u8 action){
  const char *zName;
  switch( action ){
................................................................................
  Token *pValue,      /* Token for <value>, or NULL */
  int minusFlag       /* True if a '-' sign preceded <value> */
){
  char *zLeft = 0;       /* Nul-terminated UTF-8 string <id> */
  char *zRight = 0;      /* Nul-terminated UTF-8 string <value>, or NULL */
  const char *zDb = 0;   /* The database name */
  Token *pId;            /* Pointer to <id> token */
  int iDb;               /* Database index for <database> */
  char *aFcntl[4];       /* Argument to SQLITE_FCNTL_PRAGMA */


  int rc;                      /* return value form SQLITE_FCNTL_PRAGMA */
  sqlite3 *db = pParse->db;    /* The database connection */
  Db *pDb;                     /* The specific database being pragmaed */
  Vdbe *v = sqlite3GetVdbe(pParse);  /* Prepared statement */

  if( v==0 ) return;
  sqlite3VdbeRunOnlyOnce(v);
................................................................................
      int mem = ++pParse->nMem;
      sqlite3VdbeAddOp4(v, OP_String8, 0, mem, 0, aFcntl[0], 0);
      sqlite3VdbeSetNumCols(v, 1);
      sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "result", SQLITE_STATIC);
      sqlite3VdbeAddOp2(v, OP_ResultRow, mem, 1);
      sqlite3_free(aFcntl[0]);
    }


  }else if( rc!=SQLITE_NOTFOUND ){
    if( aFcntl[0] ){
      sqlite3ErrorMsg(pParse, "%s", aFcntl[0]);
      sqlite3_free(aFcntl[0]);
    }
    pParse->nErr++;
    pParse->rc = rc;












  }else

                            
 










#if !defined(SQLITE_OMIT_PAGER_PRAGMAS) && !defined(SQLITE_OMIT_DEPRECATED)
  /*
  **  PRAGMA [database.]default_cache_size
  **  PRAGMA [database.]default_cache_size=N
  **
  ** The first form reports the current persistent setting for the
  ** page cache size.  The value returned is the maximum number of
................................................................................
  **
  ** Older versions of SQLite would set the default cache size to a
  ** negative number to indicate synchronous=OFF.  These days, synchronous
  ** is always on by default regardless of the sign of the default cache
  ** size.  But continue to take the absolute value of the default cache
  ** size of historical compatibility.
  */
  if( sqlite3StrICmp(zLeft,"default_cache_size")==0 ){
    static const VdbeOpList getCacheSize[] = {
      { OP_Transaction, 0, 0,        0},                         /* 0 */
      { OP_ReadCookie,  0, 1,        BTREE_DEFAULT_CACHE_SIZE},  /* 1 */
      { OP_IfPos,       1, 8,        0},
      { OP_Integer,     0, 2,        0},
      { OP_Subtract,    1, 2,        1},
      { OP_IfPos,       1, 8,        0},
      { OP_Integer,     0, 1,        0},                         /* 6 */
      { OP_Noop,        0, 0,        0},
      { OP_ResultRow,   1, 1,        0},
    };
    int addr;
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    sqlite3VdbeUsesBtree(v, iDb);
    if( !zRight ){
      sqlite3VdbeSetNumCols(v, 1);
      sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "cache_size", SQLITE_STATIC);
      pParse->nMem += 2;
      addr = sqlite3VdbeAddOpList(v, ArraySize(getCacheSize), getCacheSize);
      sqlite3VdbeChangeP1(v, addr, iDb);
................................................................................
      sqlite3BeginWriteOperation(pParse, 0, iDb);
      sqlite3VdbeAddOp2(v, OP_Integer, size, 1);
      sqlite3VdbeAddOp3(v, OP_SetCookie, iDb, BTREE_DEFAULT_CACHE_SIZE, 1);
      assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
      pDb->pSchema->cache_size = size;
      sqlite3BtreeSetCacheSize(pDb->pBt, pDb->pSchema->cache_size);
    }
  }else

#endif /* !SQLITE_OMIT_PAGER_PRAGMAS && !SQLITE_OMIT_DEPRECATED */

#if !defined(SQLITE_OMIT_PAGER_PRAGMAS)
  /*
  **  PRAGMA [database.]page_size
  **  PRAGMA [database.]page_size=N
  **
  ** The first form reports the current setting for the
  ** database page size in bytes.  The second form sets the
  ** database page size value.  The value can only be set if
  ** the database has not yet been created.
  */
  if( sqlite3StrICmp(zLeft,"page_size")==0 ){
    Btree *pBt = pDb->pBt;
    assert( pBt!=0 );
    if( !zRight ){
      int size = ALWAYS(pBt) ? sqlite3BtreeGetPageSize(pBt) : 0;
      returnSingleInt(pParse, "page_size", size);
    }else{
      /* Malloc may fail when setting the page-size, as there is an internal
................................................................................
      ** buffer that the pager module resizes using sqlite3_realloc().
      */
      db->nextPagesize = sqlite3Atoi(zRight);
      if( SQLITE_NOMEM==sqlite3BtreeSetPageSize(pBt, db->nextPagesize,-1,0) ){
        db->mallocFailed = 1;
      }
    }
  }else


  /*
  **  PRAGMA [database.]secure_delete
  **  PRAGMA [database.]secure_delete=ON/OFF
  **
  ** The first form reports the current setting for the
  ** secure_delete flag.  The second form changes the secure_delete
  ** flag setting and reports thenew value.
  */
  if( sqlite3StrICmp(zLeft,"secure_delete")==0 ){
    Btree *pBt = pDb->pBt;
    int b = -1;
    assert( pBt!=0 );
    if( zRight ){
      b = sqlite3GetBoolean(zRight, 0);
    }
    if( pId2->n==0 && b>=0 ){
................................................................................
      int ii;
      for(ii=0; ii<db->nDb; ii++){
        sqlite3BtreeSecureDelete(db->aDb[ii].pBt, b);
      }
    }
    b = sqlite3BtreeSecureDelete(pBt, b);
    returnSingleInt(pParse, "secure_delete", b);
  }else


  /*
  **  PRAGMA [database.]max_page_count
  **  PRAGMA [database.]max_page_count=N
  **
  ** The first form reports the current setting for the
  ** maximum number of pages in the database file.  The 
................................................................................
  ** change.  The only purpose is to provide an easy way to test
  ** the sqlite3AbsInt32() function.
  **
  **  PRAGMA [database.]page_count
  **
  ** Return the number of pages in the specified database.
  */
  if( sqlite3StrICmp(zLeft,"page_count")==0
   || sqlite3StrICmp(zLeft,"max_page_count")==0
  ){
    int iReg;
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    sqlite3CodeVerifySchema(pParse, iDb);
    iReg = ++pParse->nMem;
    if( sqlite3Tolower(zLeft[0])=='p' ){
      sqlite3VdbeAddOp2(v, OP_Pagecount, iDb, iReg);
    }else{
      sqlite3VdbeAddOp3(v, OP_MaxPgcnt, iDb, iReg, 
                        sqlite3AbsInt32(sqlite3Atoi(zRight)));
    }
    sqlite3VdbeAddOp2(v, OP_ResultRow, iReg, 1);
    sqlite3VdbeSetNumCols(v, 1);
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, zLeft, SQLITE_TRANSIENT);
  }else


  /*
  **  PRAGMA [database.]locking_mode
  **  PRAGMA [database.]locking_mode = (normal|exclusive)
  */
  if( sqlite3StrICmp(zLeft,"locking_mode")==0 ){
    const char *zRet = "normal";
    int eMode = getLockingMode(zRight);

    if( pId2->n==0 && eMode==PAGER_LOCKINGMODE_QUERY ){
      /* Simple "PRAGMA locking_mode;" statement. This is a query for
      ** the current default locking mode (which may be different to
      ** the locking-mode of the main database).
................................................................................
        }
        db->dfltLockMode = (u8)eMode;
      }
      pPager = sqlite3BtreePager(pDb->pBt);
      eMode = sqlite3PagerLockingMode(pPager, eMode);
    }


    assert(eMode==PAGER_LOCKINGMODE_NORMAL||eMode==PAGER_LOCKINGMODE_EXCLUSIVE);
    if( eMode==PAGER_LOCKINGMODE_EXCLUSIVE ){
      zRet = "exclusive";
    }
    sqlite3VdbeSetNumCols(v, 1);
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "locking_mode", SQLITE_STATIC);
    sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, zRet, 0);
    sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
  }else


  /*
  **  PRAGMA [database.]journal_mode
  **  PRAGMA [database.]journal_mode =
  **                      (delete|persist|off|truncate|memory|wal|off)
  */
  if( sqlite3StrICmp(zLeft,"journal_mode")==0 ){
    int eMode;        /* One of the PAGER_JOURNALMODE_XXX symbols */
    int ii;           /* Loop counter */

    /* Force the schema to be loaded on all databases.  This causes all
    ** database files to be opened and the journal_modes set.  This is
    ** necessary because subsequent processing must know if the databases
    ** are in WAL mode. */
    if( sqlite3ReadSchema(pParse) ){
      goto pragma_out;
    }

    sqlite3VdbeSetNumCols(v, 1);
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "journal_mode", SQLITE_STATIC);

    if( zRight==0 ){
      /* If there is no "=MODE" part of the pragma, do a query for the
      ** current mode */
      eMode = PAGER_JOURNALMODE_QUERY;
................................................................................
    for(ii=db->nDb-1; ii>=0; ii--){
      if( db->aDb[ii].pBt && (ii==iDb || pId2->n==0) ){
        sqlite3VdbeUsesBtree(v, ii);
        sqlite3VdbeAddOp3(v, OP_JournalMode, ii, 1, eMode);
      }
    }
    sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
  }else


  /*
  **  PRAGMA [database.]journal_size_limit
  **  PRAGMA [database.]journal_size_limit=N
  **
  ** Get or set the size limit on rollback journal files.
  */
  if( sqlite3StrICmp(zLeft,"journal_size_limit")==0 ){
    Pager *pPager = sqlite3BtreePager(pDb->pBt);
    i64 iLimit = -2;
    if( zRight ){
      sqlite3Atoi64(zRight, &iLimit, 1000000, SQLITE_UTF8);
      if( iLimit<-1 ) iLimit = -1;
    }
    iLimit = sqlite3PagerJournalSizeLimit(pPager, iLimit);
    returnSingleInt(pParse, "journal_size_limit", iLimit);
  }else


#endif /* SQLITE_OMIT_PAGER_PRAGMAS */

  /*
  **  PRAGMA [database.]auto_vacuum
  **  PRAGMA [database.]auto_vacuum=N
  **
  ** Get or set the value of the database 'auto-vacuum' parameter.
  ** The value is one of:  0 NONE 1 FULL 2 INCREMENTAL
  */
#ifndef SQLITE_OMIT_AUTOVACUUM
  if( sqlite3StrICmp(zLeft,"auto_vacuum")==0 ){
    Btree *pBt = pDb->pBt;
    assert( pBt!=0 );
    if( sqlite3ReadSchema(pParse) ){
      goto pragma_out;
    }
    if( !zRight ){
      int auto_vacuum;
      if( ALWAYS(pBt) ){
         auto_vacuum = sqlite3BtreeGetAutoVacuum(pBt);
      }else{
         auto_vacuum = SQLITE_DEFAULT_AUTOVACUUM;
      }
      returnSingleInt(pParse, "auto_vacuum", auto_vacuum);
    }else{
      int eAuto = getAutoVacuum(zRight);
      assert( eAuto>=0 && eAuto<=2 );
      db->nextAutovac = (u8)eAuto;
      if( ALWAYS(eAuto>=0) ){
        /* Call SetAutoVacuum() to set initialize the internal auto and
        ** incr-vacuum flags. This is required in case this connection
        ** creates the database file. It is important that it is created
        ** as an auto-vacuum capable db.
        */
        rc = sqlite3BtreeSetAutoVacuum(pBt, eAuto);
        if( rc==SQLITE_OK && (eAuto==1 || eAuto==2) ){
          /* When setting the auto_vacuum mode to either "full" or 
          ** "incremental", write the value of meta[6] in the database
          ** file. Before writing to meta[6], check that meta[3] indicates
          ** that this really is an auto-vacuum capable database.
          */
          static const VdbeOpList setMeta6[] = {
            { OP_Transaction,    0,         1,                 0},    /* 0 */
            { OP_ReadCookie,     0,         1,         BTREE_LARGEST_ROOT_PAGE},
            { OP_If,             1,         0,                 0},    /* 2 */
            { OP_Halt,           SQLITE_OK, OE_Abort,          0},    /* 3 */
            { OP_Integer,        0,         1,                 0},    /* 4 */
            { OP_SetCookie,      0,         BTREE_INCR_VACUUM, 1},    /* 5 */
          };
          int iAddr;
          iAddr = sqlite3VdbeAddOpList(v, ArraySize(setMeta6), setMeta6);
          sqlite3VdbeChangeP1(v, iAddr, iDb);
          sqlite3VdbeChangeP1(v, iAddr+1, iDb);
          sqlite3VdbeChangeP2(v, iAddr+2, iAddr+4);
          sqlite3VdbeChangeP1(v, iAddr+4, eAuto-1);
          sqlite3VdbeChangeP1(v, iAddr+5, iDb);
          sqlite3VdbeUsesBtree(v, iDb);
        }
      }

    }
  }else
#endif

  /*
  **  PRAGMA [database.]incremental_vacuum(N)
  **
  ** Do N steps of incremental vacuuming on a database.
  */
#ifndef SQLITE_OMIT_AUTOVACUUM
  if( sqlite3StrICmp(zLeft,"incremental_vacuum")==0 ){

    int iLimit, addr;
    if( sqlite3ReadSchema(pParse) ){
      goto pragma_out;
    }
    if( zRight==0 || !sqlite3GetInt32(zRight, &iLimit) || iLimit<=0 ){
      iLimit = 0x7fffffff;
    }
    sqlite3BeginWriteOperation(pParse, 0, iDb);
    sqlite3VdbeAddOp2(v, OP_Integer, iLimit, 1);
    addr = sqlite3VdbeAddOp1(v, OP_IncrVacuum, iDb);
    sqlite3VdbeAddOp1(v, OP_ResultRow, 1);
    sqlite3VdbeAddOp2(v, OP_AddImm, 1, -1);
    sqlite3VdbeAddOp2(v, OP_IfPos, 1, addr);
    sqlite3VdbeJumpHere(v, addr);
  }else

#endif

#ifndef SQLITE_OMIT_PAGER_PRAGMAS
  /*
  **  PRAGMA [database.]cache_size
  **  PRAGMA [database.]cache_size=N
  **
................................................................................
  ** The first form reports the current local setting for the
  ** page cache size. The second form sets the local
  ** page cache size value.  If N is positive then that is the
  ** number of pages in the cache.  If N is negative, then the
  ** number of pages is adjusted so that the cache uses -N kibibytes
  ** of memory.
  */
  if( sqlite3StrICmp(zLeft,"cache_size")==0 ){
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
    if( !zRight ){
      returnSingleInt(pParse, "cache_size", pDb->pSchema->cache_size);
    }else{
      int size = sqlite3Atoi(zRight);
      pDb->pSchema->cache_size = size;
      sqlite3BtreeSetCacheSize(pDb->pBt, pDb->pSchema->cache_size);
    }
  }else


  /*
  **  PRAGMA [database.]mmap_size(N)
  **
  ** Used to set mapping size limit. The mapping size limit is
  ** used to limit the aggregate size of all memory mapped regions of the
  ** database file. If this parameter is set to zero, then memory mapping
................................................................................
  ** limit determined by sqlite3_config(SQLITE_CONFIG_MMAP_SIZE) is set.
  ** The parameter N is measured in bytes.
  **
  ** This value is advisory.  The underlying VFS is free to memory map
  ** as little or as much as it wants.  Except, if N is set to 0 then the
  ** upper layers will never invoke the xFetch interfaces to the VFS.
  */
  if( sqlite3StrICmp(zLeft,"mmap_size")==0 ){
    sqlite3_int64 sz;

    assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
    if( zRight ){
      int ii;
      sqlite3Atoi64(zRight, &sz, 1000, SQLITE_UTF8);
      if( sz<0 ) sz = sqlite3GlobalConfig.szMmap;
      if( pId2->n==0 ) db->szMmap = sz;
      for(ii=db->nDb-1; ii>=0; ii--){
        if( db->aDb[ii].pBt && (ii==iDb || pId2->n==0) ){
          sqlite3BtreeSetMmapLimit(db->aDb[ii].pBt, sz);
        }
      }
    }
    sz = -1;
    rc = sqlite3_file_control(db, zDb, SQLITE_FCNTL_MMAP_SIZE, &sz);
#if SQLITE_MAX_MMAP_SIZE==0
    sz = 0;

#endif
    if( rc==SQLITE_OK ){
      returnSingleInt(pParse, "mmap_size", sz);
    }else if( rc!=SQLITE_NOTFOUND ){
      pParse->nErr++;
      pParse->rc = rc;
    }
  }else


  /*
  **   PRAGMA temp_store
  **   PRAGMA temp_store = "default"|"memory"|"file"
  **
  ** Return or set the local value of the temp_store flag.  Changing
  ** the local value does not make changes to the disk file and the default
  ** value will be restored the next time the database is opened.
  **
  ** Note that it is possible for the library compile-time options to
  ** override this setting
  */
  if( sqlite3StrICmp(zLeft, "temp_store")==0 ){
    if( !zRight ){
      returnSingleInt(pParse, "temp_store", db->temp_store);
    }else{
      changeTempStorage(pParse, zRight);
    }
  }else


  /*
  **   PRAGMA temp_store_directory
  **   PRAGMA temp_store_directory = ""|"directory_name"
  **
  ** Return or set the local value of the temp_store_directory flag.  Changing
  ** the value sets a specific directory to be used for temporary files.
  ** Setting to a null string reverts to the default temporary directory search.
  ** If temporary directory is changed, then invalidateTempStorage.
  **
  */
  if( sqlite3StrICmp(zLeft, "temp_store_directory")==0 ){
    if( !zRight ){
      if( sqlite3_temp_directory ){
        sqlite3VdbeSetNumCols(v, 1);
        sqlite3VdbeSetColName(v, 0, COLNAME_NAME, 
            "temp_store_directory", SQLITE_STATIC);
        sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, sqlite3_temp_directory, 0);
        sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
................................................................................
      if( zRight[0] ){
        sqlite3_temp_directory = sqlite3_mprintf("%s", zRight);
      }else{
        sqlite3_temp_directory = 0;
      }
#endif /* SQLITE_OMIT_WSD */
    }
  }else


#if SQLITE_OS_WIN
  /*
  **   PRAGMA data_store_directory
  **   PRAGMA data_store_directory = ""|"directory_name"
  **
  ** Return or set the local value of the data_store_directory flag.  Changing
................................................................................
  ** were specified with a relative pathname.  Setting to a null string reverts
  ** to the default database directory, which for database files specified with
  ** a relative path will probably be based on the current directory for the
  ** process.  Database file specified with an absolute path are not impacted
  ** by this setting, regardless of its value.
  **
  */
  if( sqlite3StrICmp(zLeft, "data_store_directory")==0 ){
    if( !zRight ){
      if( sqlite3_data_directory ){
        sqlite3VdbeSetNumCols(v, 1);
        sqlite3VdbeSetColName(v, 0, COLNAME_NAME, 
            "data_store_directory", SQLITE_STATIC);
        sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, sqlite3_data_directory, 0);
        sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
................................................................................
      if( zRight[0] ){
        sqlite3_data_directory = sqlite3_mprintf("%s", zRight);
      }else{
        sqlite3_data_directory = 0;
      }
#endif /* SQLITE_OMIT_WSD */
    }
  }else
#endif

#if !defined(SQLITE_ENABLE_LOCKING_STYLE)
#  if defined(__APPLE__)
#    define SQLITE_ENABLE_LOCKING_STYLE 1
#  else
#    define SQLITE_ENABLE_LOCKING_STYLE 0
#  endif
#endif

#if SQLITE_ENABLE_LOCKING_STYLE
  /*
   **   PRAGMA [database.]lock_proxy_file
   **   PRAGMA [database.]lock_proxy_file = ":auto:"|"lock_file_path"
   **
   ** Return or set the value of the lock_proxy_file flag.  Changing
   ** the value sets a specific file to be used for database access locks.
   **
   */
  if( sqlite3StrICmp(zLeft, "lock_proxy_file")==0 ){

    if( !zRight ){
      Pager *pPager = sqlite3BtreePager(pDb->pBt);
      char *proxy_file_path = NULL;
      sqlite3_file *pFile = sqlite3PagerFile(pPager);
      sqlite3OsFileControlHint(pFile, SQLITE_GET_LOCKPROXYFILE, 
                           &proxy_file_path);
      
................................................................................
                                     NULL);
      }
      if( res!=SQLITE_OK ){
        sqlite3ErrorMsg(pParse, "failed to set lock proxy file");
        goto pragma_out;
      }
    }
  }else

#endif /* SQLITE_ENABLE_LOCKING_STYLE */      
    
  /*
  **   PRAGMA [database.]synchronous
  **   PRAGMA [database.]synchronous=OFF|ON|NORMAL|FULL
  **
  ** Return or set the local value of the synchronous flag.  Changing
  ** the local value does not make changes to the disk file and the
  ** default value will be restored the next time the database is
  ** opened.
  */
  if( sqlite3StrICmp(zLeft,"synchronous")==0 ){
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    if( !zRight ){
      returnSingleInt(pParse, "synchronous", pDb->safety_level-1);
    }else{
      if( !db->autoCommit ){
        sqlite3ErrorMsg(pParse, 
            "Safety level may not be changed inside a transaction");
      }else{
        pDb->safety_level = getSafetyLevel(zRight,0,1)+1;
        setAllPagerFlags(db);
      }
    }
  }else

#endif /* SQLITE_OMIT_PAGER_PRAGMAS */

#ifndef SQLITE_OMIT_FLAG_PRAGMAS
  if( flagPragma(pParse, zLeft, zRight) ){
    setAllPagerFlags(db);



  }else























#endif /* SQLITE_OMIT_FLAG_PRAGMAS */

#ifndef SQLITE_OMIT_SCHEMA_PRAGMAS
  /*
  **   PRAGMA table_info(<table>)
  **
  ** Return a single row for each column of the named table. The columns of
................................................................................
  **
  ** cid:        Column id (numbered from left to right, starting at 0)
  ** name:       Column name
  ** type:       Column declaration type.
  ** notnull:    True if 'NOT NULL' is part of column declaration
  ** dflt_value: The default value for the column, if any.
  */
  if( sqlite3StrICmp(zLeft, "table_info")==0 && zRight ){
    Table *pTab;
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    pTab = sqlite3FindTable(db, zRight, zDb);
    if( pTab ){
      int i, k;
      int nHidden = 0;
      Column *pCol;
      Index *pPk;
      for(pPk=pTab->pIndex; pPk && pPk->autoIndex!=2; pPk=pPk->pNext){}
................................................................................
        }else{
          for(k=1; ALWAYS(k<=pTab->nCol) && pPk->aiColumn[k-1]!=i; k++){}
        }
        sqlite3VdbeAddOp2(v, OP_Integer, k, 6);
        sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 6);
      }
    }
  }else

  if( sqlite3StrICmp(zLeft, "index_info")==0 && zRight ){



    Index *pIdx;






























    Table *pTab;
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    pIdx = sqlite3FindIndex(db, zRight, zDb);
    if( pIdx ){
      int i;
      pTab = pIdx->pTable;
      sqlite3VdbeSetNumCols(v, 3);
      pParse->nMem = 3;
      sqlite3CodeVerifySchema(pParse, iDb);
................................................................................
        sqlite3VdbeAddOp2(v, OP_Integer, i, 1);
        sqlite3VdbeAddOp2(v, OP_Integer, cnum, 2);
        assert( pTab->nCol>cnum );
        sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0, pTab->aCol[cnum].zName, 0);
        sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 3);
      }
    }
  }else

  if( sqlite3StrICmp(zLeft, "index_list")==0 && zRight ){



    Index *pIdx;
    Table *pTab;
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;

    pTab = sqlite3FindTable(db, zRight, zDb);
    if( pTab ){
      v = sqlite3GetVdbe(pParse);
      pIdx = pTab->pIndex;
      if( pIdx ){
        int i = 0; 
        sqlite3VdbeSetNumCols(v, 3);
        pParse->nMem = 3;
        sqlite3CodeVerifySchema(pParse, iDb);
        sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seq", SQLITE_STATIC);
        sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", SQLITE_STATIC);
        sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "unique", SQLITE_STATIC);
        while(pIdx){

          sqlite3VdbeAddOp2(v, OP_Integer, i, 1);
          sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, pIdx->zName, 0);
          sqlite3VdbeAddOp2(v, OP_Integer, pIdx->onError!=OE_None, 3);
          sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 3);
          ++i;
          pIdx = pIdx->pNext;
        }
      }
    }
  }else


  if( sqlite3StrICmp(zLeft, "database_list")==0 ){

    int i;
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    sqlite3VdbeSetNumCols(v, 3);
    pParse->nMem = 3;
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seq", SQLITE_STATIC);
    sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", SQLITE_STATIC);
    sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "file", SQLITE_STATIC);
    for(i=0; i<db->nDb; i++){
      if( db->aDb[i].pBt==0 ) continue;
................................................................................
      assert( db->aDb[i].zName!=0 );
      sqlite3VdbeAddOp2(v, OP_Integer, i, 1);
      sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, db->aDb[i].zName, 0);
      sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0,
           sqlite3BtreeGetFilename(db->aDb[i].pBt), 0);
      sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 3);
    }
  }else

  if( sqlite3StrICmp(zLeft, "collation_list")==0 ){



    int i = 0;
    HashElem *p;
    sqlite3VdbeSetNumCols(v, 2);
    pParse->nMem = 2;
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seq", SQLITE_STATIC);
    sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", SQLITE_STATIC);
    for(p=sqliteHashFirst(&db->aCollSeq); p; p=sqliteHashNext(p)){
      CollSeq *pColl = (CollSeq *)sqliteHashData(p);
      sqlite3VdbeAddOp2(v, OP_Integer, i++, 1);
      sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, pColl->zName, 0);
      sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 2);
    }
  }else

#endif /* SQLITE_OMIT_SCHEMA_PRAGMAS */

#ifndef SQLITE_OMIT_FOREIGN_KEY
  if( sqlite3StrICmp(zLeft, "foreign_key_list")==0 && zRight ){
    FKey *pFK;
    Table *pTab;
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    pTab = sqlite3FindTable(db, zRight, zDb);
    if( pTab ){
      v = sqlite3GetVdbe(pParse);
      pFK = pTab->pFKey;
      if( pFK ){
        int i = 0; 
        sqlite3VdbeSetNumCols(v, 8);
................................................................................
            sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 8);
          }
          ++i;
          pFK = pFK->pNextFrom;
        }
      }
    }
  }else

#endif /* !defined(SQLITE_OMIT_FOREIGN_KEY) */

#ifndef SQLITE_OMIT_FOREIGN_KEY
#ifndef SQLITE_OMIT_TRIGGER
  if( sqlite3StrICmp(zLeft, "foreign_key_check")==0 ){
    FKey *pFK;             /* A foreign key constraint */
    Table *pTab;           /* Child table contain "REFERENCES" keyword */
    Table *pParent;        /* Parent table that child points to */
    Index *pIdx;           /* Index in the parent table */
    int i;                 /* Loop counter:  Foreign key number for pTab */
    int j;                 /* Loop counter:  Field of the foreign key */
    HashElem *k;           /* Loop counter:  Next table in schema */
................................................................................
    int regResult;         /* 3 registers to hold a result row */
    int regKey;            /* Register to hold key for checking the FK */
    int regRow;            /* Registers to hold a row from pTab */
    int addrTop;           /* Top of a loop checking foreign keys */
    int addrOk;            /* Jump here if the key is OK */
    int *aiCols;           /* child to parent column mapping */

    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    regResult = pParse->nMem+1;
    pParse->nMem += 4;
    regKey = ++pParse->nMem;
    regRow = ++pParse->nMem;
    v = sqlite3GetVdbe(pParse);
    sqlite3VdbeSetNumCols(v, 4);
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "table", SQLITE_STATIC);
................................................................................
        sqlite3VdbeAddOp2(v, OP_ResultRow, regResult, 4);
        sqlite3VdbeResolveLabel(v, addrOk);
        sqlite3DbFree(db, aiCols);
      }
      sqlite3VdbeAddOp2(v, OP_Next, 0, addrTop+1);
      sqlite3VdbeJumpHere(v, addrTop);
    }
  }else

#endif /* !defined(SQLITE_OMIT_TRIGGER) */
#endif /* !defined(SQLITE_OMIT_FOREIGN_KEY) */

#ifndef NDEBUG
  if( sqlite3StrICmp(zLeft, "parser_trace")==0 ){
    if( zRight ){
      if( sqlite3GetBoolean(zRight, 0) ){
        sqlite3ParserTrace(stderr, "parser: ");
      }else{
        sqlite3ParserTrace(0, 0);
      }
    }
  }else

#endif

  /* Reinstall the LIKE and GLOB functions.  The variant of LIKE
  ** used will be case sensitive or not depending on the RHS.
  */
  if( sqlite3StrICmp(zLeft, "case_sensitive_like")==0 ){
    if( zRight ){
      sqlite3RegisterLikeFunctions(db, sqlite3GetBoolean(zRight, 0));
    }
  }else


#ifndef SQLITE_INTEGRITY_CHECK_ERROR_MAX
# define SQLITE_INTEGRITY_CHECK_ERROR_MAX 100
#endif

#ifndef SQLITE_OMIT_INTEGRITY_CHECK
  /* Pragma "quick_check" is reduced version of 
  ** integrity_check designed to detect most database corruption
  ** without most of the overhead of a full integrity-check.
  */
  if( sqlite3StrICmp(zLeft, "integrity_check")==0
   || sqlite3StrICmp(zLeft, "quick_check")==0 
  ){
    int i, j, addr, mxErr;

    /* Code that appears at the end of the integrity check.  If no error
    ** messages have been generated, output OK.  Otherwise output the
    ** error message
    */
    static const VdbeOpList endCode[] = {
................................................................................
    ** to -1 here, to indicate that the VDBE should verify the integrity
    ** of all attached databases.  */
    assert( iDb>=0 );
    assert( iDb==0 || pId2->z );
    if( pId2->z==0 ) iDb = -1;

    /* Initialize the VDBE program */
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    pParse->nMem = 6;
    sqlite3VdbeSetNumCols(v, 1);
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "integrity_check", SQLITE_STATIC);

    /* Set the maximum error count */
    mxErr = SQLITE_INTEGRITY_CHECK_ERROR_MAX;
    if( zRight ){
................................................................................
#endif /* SQLITE_OMIT_BTREECOUNT */
      } 
    }
    addr = sqlite3VdbeAddOpList(v, ArraySize(endCode), endCode);
    sqlite3VdbeChangeP2(v, addr, -mxErr);
    sqlite3VdbeJumpHere(v, addr+1);
    sqlite3VdbeChangeP4(v, addr+2, "ok", P4_STATIC);
  }else

#endif /* SQLITE_OMIT_INTEGRITY_CHECK */

#ifndef SQLITE_OMIT_UTF16
  /*
  **   PRAGMA encoding
  **   PRAGMA encoding = "utf-8"|"utf-16"|"utf-16le"|"utf-16be"
  **
................................................................................
  ** the main database has not been initialized and/or created when ATTACH
  ** is executed, this is done before the ATTACH operation.
  **
  ** In the second form this pragma sets the text encoding to be used in
  ** new database files created using this database handle. It is only
  ** useful if invoked immediately after the main database i
  */
  if( sqlite3StrICmp(zLeft, "encoding")==0 ){
    static const struct EncName {
      char *zName;
      u8 enc;
    } encnames[] = {
      { "UTF8",     SQLITE_UTF8        },
      { "UTF-8",    SQLITE_UTF8        },  /* Must be element [1] */
      { "UTF-16le", SQLITE_UTF16LE     },  /* Must be element [2] */
................................................................................
          }
        }
        if( !pEnc->zName ){
          sqlite3ErrorMsg(pParse, "unsupported encoding: %s", zRight);
        }
      }
    }
  }else

#endif /* SQLITE_OMIT_UTF16 */

#ifndef SQLITE_OMIT_SCHEMA_VERSION_PRAGMAS
  /*
  **   PRAGMA [database.]schema_version
  **   PRAGMA [database.]schema_version = <integer>
  **
................................................................................
  ** Subverting this mechanism by using "PRAGMA schema_version" to modify
  ** the schema-version is potentially dangerous and may lead to program
  ** crashes or database corruption. Use with caution!
  **
  ** The user-version is not used internally by SQLite. It may be used by
  ** applications for any purpose.
  */
  if( sqlite3StrICmp(zLeft, "schema_version")==0 
   || sqlite3StrICmp(zLeft, "user_version")==0 
   || sqlite3StrICmp(zLeft, "freelist_count")==0 
   || sqlite3StrICmp(zLeft, "application_id")==0 
  ){
    int iCookie;   /* Cookie index. 1 for schema-cookie, 6 for user-cookie. */
    sqlite3VdbeUsesBtree(v, iDb);
    switch( zLeft[0] ){
      case 'a': case 'A':
        iCookie = BTREE_APPLICATION_ID;
        break;
      case 'f': case 'F':
................................................................................
      int addr = sqlite3VdbeAddOpList(v, ArraySize(readCookie), readCookie);
      sqlite3VdbeChangeP1(v, addr, iDb);
      sqlite3VdbeChangeP1(v, addr+1, iDb);
      sqlite3VdbeChangeP3(v, addr+1, iCookie);
      sqlite3VdbeSetNumCols(v, 1);
      sqlite3VdbeSetColName(v, 0, COLNAME_NAME, zLeft, SQLITE_TRANSIENT);
    }
  }else

#endif /* SQLITE_OMIT_SCHEMA_VERSION_PRAGMAS */

#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
  /*
  **   PRAGMA compile_options
  **
  ** Return the names of all compile-time options used in this build,
  ** one option per row.
  */
  if( sqlite3StrICmp(zLeft, "compile_options")==0 ){
    int i = 0;
    const char *zOpt;
    sqlite3VdbeSetNumCols(v, 1);
    pParse->nMem = 1;
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "compile_option", SQLITE_STATIC);
    while( (zOpt = sqlite3_compileoption_get(i++))!=0 ){
      sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, zOpt, 0);
      sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
    }
  }else

#endif /* SQLITE_OMIT_COMPILEOPTION_DIAGS */

#ifndef SQLITE_OMIT_WAL
  /*
  **   PRAGMA [database.]wal_checkpoint = passive|full|restart
  **
  ** Checkpoint the database.
  */
  if( sqlite3StrICmp(zLeft, "wal_checkpoint")==0 ){
    int iBt = (pId2->z?iDb:SQLITE_MAX_ATTACHED);
    int eMode = SQLITE_CHECKPOINT_PASSIVE;
    if( zRight ){
      if( sqlite3StrICmp(zRight, "full")==0 ){
        eMode = SQLITE_CHECKPOINT_FULL;
      }else if( sqlite3StrICmp(zRight, "restart")==0 ){
        eMode = SQLITE_CHECKPOINT_RESTART;
      }
    }
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    sqlite3VdbeSetNumCols(v, 3);
    pParse->nMem = 3;
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "busy", SQLITE_STATIC);
    sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "log", SQLITE_STATIC);
    sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "checkpointed", SQLITE_STATIC);

    sqlite3VdbeAddOp3(v, OP_Checkpoint, iBt, eMode, 1);
    sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 3);
  }else


  /*
  **   PRAGMA wal_autocheckpoint
  **   PRAGMA wal_autocheckpoint = N
  **
  ** Configure a database connection to automatically checkpoint a database
  ** after accumulating N frames in the log. Or query for the current value
  ** of N.
  */
  if( sqlite3StrICmp(zLeft, "wal_autocheckpoint")==0 ){
    if( zRight ){
      sqlite3_wal_autocheckpoint(db, sqlite3Atoi(zRight));
    }
    returnSingleInt(pParse, "wal_autocheckpoint", 
       db->xWalCallback==sqlite3WalDefaultHook ? 
           SQLITE_PTR_TO_INT(db->pWalArg) : 0);
  }else

#endif

  /*
  **  PRAGMA shrink_memory
  **
  ** This pragma attempts to free as much memory as possible from the
  ** current database connection.
  */
  if( sqlite3StrICmp(zLeft, "shrink_memory")==0 ){
    sqlite3_db_release_memory(db);
  }else


  /*
  **   PRAGMA busy_timeout
  **   PRAGMA busy_timeout = N
  **
  ** Call sqlite3_busy_timeout(db, N).  Return the current timeout value
  ** if one is set.  If no busy handler or a different busy handler is set
  ** then 0 is returned.  Setting the busy_timeout to 0 or negative
  ** disables the timeout.
  */
  if( sqlite3StrICmp(zLeft, "busy_timeout")==0 ){

    if( zRight ){
      sqlite3_busy_timeout(db, sqlite3Atoi(zRight));
    }
    returnSingleInt(pParse, "timeout",  db->busyTimeout);
  }else


















#if defined(SQLITE_DEBUG) || defined(SQLITE_TEST)
  /*
  ** Report the current state of file logs for all databases
  */
  if( sqlite3StrICmp(zLeft, "lock_status")==0 ){
    static const char *const azLockName[] = {
      "unlocked", "shared", "reserved", "pending", "exclusive"
    };
    int i;
    sqlite3VdbeSetNumCols(v, 2);
    pParse->nMem = 2;
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "database", SQLITE_STATIC);
................................................................................
      }else if( sqlite3_file_control(db, i ? db->aDb[i].zName : 0, 
                                     SQLITE_FCNTL_LOCKSTATE, &j)==SQLITE_OK ){
         zState = azLockName[j];
      }
      sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, zState, P4_STATIC);
      sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 2);
    }


  }else
#endif

#ifdef SQLITE_HAS_CODEC
  if( sqlite3StrICmp(zLeft, "key")==0 && zRight ){
    sqlite3_key_v2(db, zDb, zRight, sqlite3Strlen30(zRight));
  }else
  if( sqlite3StrICmp(zLeft, "rekey")==0 && zRight ){


    sqlite3_rekey_v2(db, zDb, zRight, sqlite3Strlen30(zRight));
  }else
  if( zRight && (sqlite3StrICmp(zLeft, "hexkey")==0 ||
                 sqlite3StrICmp(zLeft, "hexrekey")==0) ){




    int i, h1, h2;
    char zKey[40];
    for(i=0; (h1 = zRight[i])!=0 && (h2 = zRight[i+1])!=0; i+=2){
      h1 += 9*(1&(h1>>6));
      h2 += 9*(1&(h2>>6));
      zKey[i/2] = (h2 & 0x0f) | ((h1 & 0xf)<<4);


    }
    if( (zLeft[3] & 0xf)==0xb ){
      sqlite3_key_v2(db, zDb, zKey, i/2);
    }else{
      sqlite3_rekey_v2(db, zDb, zKey, i/2);
    }
  }else



#endif
#if defined(SQLITE_HAS_CODEC) || defined(SQLITE_ENABLE_CEROD)
  if( sqlite3StrICmp(zLeft, "activate_extensions")==0 && zRight ){

#ifdef SQLITE_HAS_CODEC
    if( sqlite3StrNICmp(zRight, "see-", 4)==0 ){
      sqlite3_activate_see(&zRight[4]);
    }
#endif
#ifdef SQLITE_ENABLE_CEROD
    if( sqlite3StrNICmp(zRight, "cerod-", 6)==0 ){
      sqlite3_activate_cerod(&zRight[6]);
    }
#endif
  }else


#endif

 
  {/* Empty ELSE clause */}

pragma_out:
  sqlite3DbFree(db, zLeft);
  sqlite3DbFree(db, zRight);
}

#endif /* SQLITE_OMIT_PRAGMA */
................................................................................

  pE1 = sqlite3CreateColumnExpr(db, pSrc, iLeft, iColLeft);
  pE2 = sqlite3CreateColumnExpr(db, pSrc, iRight, iColRight);

  pEq = sqlite3PExpr(pParse, TK_EQ, pE1, pE2, 0);
  if( pEq && isOuterJoin ){
    ExprSetProperty(pEq, EP_FromJoin);
    assert( !ExprHasAnyProperty(pEq, EP_TokenOnly|EP_Reduced) );
    ExprSetIrreducible(pEq);
    pEq->iRightJoinTable = (i16)pE2->iTable;
  }
  *ppWhere = sqlite3ExprAnd(db, *ppWhere, pEq);
}

/*
** Set the EP_FromJoin property on all terms of the given expression.
................................................................................
** defer the handling of t1.x=5, it will be processed immediately
** after the t1 loop and rows with t1.x!=5 will never appear in
** the output, which is incorrect.
*/
static void setJoinExpr(Expr *p, int iTable){
  while( p ){
    ExprSetProperty(p, EP_FromJoin);
    assert( !ExprHasAnyProperty(p, EP_TokenOnly|EP_Reduced) );
    ExprSetIrreducible(p);
    p->iRightJoinTable = (i16)iTable;
    setJoinExpr(p->pLeft, iTable);
    p = p->pRight;
  } 
}

/*
................................................................................
    sqlite3VdbeAddOp2(v, OP_Close, pseudoTab, 0);
  }
}

/*
** Return a pointer to a string containing the 'declaration type' of the
** expression pExpr. The string may be treated as static by the caller.



**
** The declaration type is the exact datatype definition extracted from the
** original CREATE TABLE statement if the expression is a column. The
** declaration type for a ROWID field is INTEGER. Exactly when an expression
** is considered a column can be complex in the presence of subqueries. The
** result-set expression in all of the following SELECT statements is 
** considered a column by this function.
................................................................................
**
**   SELECT col FROM tbl;
**   SELECT (SELECT col FROM tbl;
**   SELECT (SELECT col FROM tbl);
**   SELECT abc FROM (SELECT col AS abc FROM tbl);
** 
** The declaration type for any expression other than a column is NULL.



*/


static const char *columnType(
  NameContext *pNC, 
  Expr *pExpr,
  const char **pzOriginDb,
  const char **pzOriginTab,
  const char **pzOriginCol

){
  char const *zType = 0;
  char const *zOriginDb = 0;
  char const *zOriginTab = 0;








  char const *zOriginCol = 0;
  int j;
  if( NEVER(pExpr==0) || pNC->pSrcList==0 ) return 0;



  switch( pExpr->op ){
    case TK_AGG_COLUMN:
    case TK_COLUMN: {
      /* The expression is a column. Locate the table the column is being
      ** extracted from in NameContext.pSrcList. This table may be real
      ** database table or a subquery.
      */
................................................................................
          ** test case misc2.2.2) - it always evaluates to NULL.
          */
          NameContext sNC;
          Expr *p = pS->pEList->a[iCol].pExpr;
          sNC.pSrcList = pS->pSrc;
          sNC.pNext = pNC;
          sNC.pParse = pNC->pParse;
          zType = columnType(&sNC, p, &zOriginDb, &zOriginTab, &zOriginCol); 
        }
      }else if( ALWAYS(pTab->pSchema) ){
        /* A real table */
        assert( !pS );
        if( iCol<0 ) iCol = pTab->iPKey;
        assert( iCol==-1 || (iCol>=0 && iCol<pTab->nCol) );

        if( iCol<0 ){
          zType = "INTEGER";
          zOriginCol = "rowid";
        }else{
          zType = pTab->aCol[iCol].zType;
          zOriginCol = pTab->aCol[iCol].zName;

        }
        zOriginTab = pTab->zName;
        if( pNC->pParse ){
          int iDb = sqlite3SchemaToIndex(pNC->pParse->db, pTab->pSchema);
          zOriginDb = pNC->pParse->db->aDb[iDb].zName;
        }








      }
      break;
    }
#ifndef SQLITE_OMIT_SUBQUERY
    case TK_SELECT: {
      /* The expression is a sub-select. Return the declaration type and
      ** origin info for the single column in the result set of the SELECT
................................................................................
      NameContext sNC;
      Select *pS = pExpr->x.pSelect;
      Expr *p = pS->pEList->a[0].pExpr;
      assert( ExprHasProperty(pExpr, EP_xIsSelect) );
      sNC.pSrcList = pS->pSrc;
      sNC.pNext = pNC;
      sNC.pParse = pNC->pParse;
      zType = columnType(&sNC, p, &zOriginDb, &zOriginTab, &zOriginCol); 
      break;
    }
#endif
  }
  

  if( pzOriginDb ){
    assert( pzOriginTab && pzOriginCol );
    *pzOriginDb = zOriginDb;
    *pzOriginTab = zOriginTab;
    *pzOriginCol = zOriginCol;
  }


  return zType;
}

/*
** Generate code that will tell the VDBE the declaration types of columns
** in the result set.
*/
................................................................................
  for(i=0; i<pEList->nExpr; i++){
    Expr *p = pEList->a[i].pExpr;
    const char *zType;
#ifdef SQLITE_ENABLE_COLUMN_METADATA
    const char *zOrigDb = 0;
    const char *zOrigTab = 0;
    const char *zOrigCol = 0;
    zType = columnType(&sNC, p, &zOrigDb, &zOrigTab, &zOrigCol);

    /* The vdbe must make its own copy of the column-type and other 
    ** column specific strings, in case the schema is reset before this
    ** virtual machine is deleted.
    */
    sqlite3VdbeSetColName(v, i, COLNAME_DATABASE, zOrigDb, SQLITE_TRANSIENT);
    sqlite3VdbeSetColName(v, i, COLNAME_TABLE, zOrigTab, SQLITE_TRANSIENT);
    sqlite3VdbeSetColName(v, i, COLNAME_COLUMN, zOrigCol, SQLITE_TRANSIENT);
#else
    zType = columnType(&sNC, p, 0, 0, 0);
#endif
    sqlite3VdbeSetColName(v, i, COLNAME_DECLTYPE, zType, SQLITE_TRANSIENT);
  }
#endif /* SQLITE_OMIT_DECLTYPE */
}

/*
** Generate code that will tell the VDBE the names of columns
** in the result set.  This information is used to provide the
** azCol[] values in the callback.
*/
................................................................................
** routine goes through and adds the types and collations.
**
** This routine requires that all identifiers in the SELECT
** statement be resolved.
*/
static void selectAddColumnTypeAndCollation(
  Parse *pParse,        /* Parsing contexts */
  int nCol,             /* Number of columns */
  Column *aCol,         /* List of columns */
  Select *pSelect       /* SELECT used to determine types and collations */
){
  sqlite3 *db = pParse->db;
  NameContext sNC;
  Column *pCol;
  CollSeq *pColl;
  int i;
  Expr *p;
  struct ExprList_item *a;


  assert( pSelect!=0 );
  assert( (pSelect->selFlags & SF_Resolved)!=0 );
  assert( nCol==pSelect->pEList->nExpr || db->mallocFailed );
  if( db->mallocFailed ) return;
  memset(&sNC, 0, sizeof(sNC));
  sNC.pSrcList = pSelect->pSrc;
  a = pSelect->pEList->a;
  for(i=0, pCol=aCol; i<nCol; i++, pCol++){
    p = a[i].pExpr;
    pCol->zType = sqlite3DbStrDup(db, columnType(&sNC, p, 0, 0, 0));

    pCol->affinity = sqlite3ExprAffinity(p);
    if( pCol->affinity==0 ) pCol->affinity = SQLITE_AFF_NONE;
    pColl = sqlite3ExprCollSeq(pParse, p);
    if( pColl ){
      pCol->zColl = sqlite3DbStrDup(db, pColl->zName);
    }
  }

}

/*
** Given a SELECT statement, generate a Table structure that describes
** the result set of that SELECT.
*/
SQLITE_PRIVATE Table *sqlite3ResultSetOfSelect(Parse *pParse, Select *pSelect){
................................................................................
    return 0;
  }
  /* The sqlite3ResultSetOfSelect() is only used n contexts where lookaside
  ** is disabled */
  assert( db->lookaside.bEnabled==0 );
  pTab->nRef = 1;
  pTab->zName = 0;
  pTab->nRowEst = 1000000;
  selectColumnsFromExprList(pParse, pSelect->pEList, &pTab->nCol, &pTab->aCol);
  selectAddColumnTypeAndCollation(pParse, pTab->nCol, pTab->aCol, pSelect);
  pTab->iPKey = -1;
  if( db->mallocFailed ){
    sqlite3DeleteTable(db, pTab);
    return 0;
  }
  return pTab;
}
................................................................................
  pTab = p->pSrc->a[0].pTab;
  pExpr = p->pEList->a[0].pExpr;
  assert( pTab && !pTab->pSelect && pExpr );

  if( IsVirtual(pTab) ) return 0;
  if( pExpr->op!=TK_AGG_FUNCTION ) return 0;
  if( NEVER(pAggInfo->nFunc==0) ) return 0;
  if( (pAggInfo->aFunc[0].pFunc->flags&SQLITE_FUNC_COUNT)==0 ) return 0;
  if( pExpr->flags&EP_Distinct ) return 0;

  return pTab;
}

/*
** If the source-list item passed as an argument was augmented with an
................................................................................
      /* A sub-query in the FROM clause of a SELECT */
      assert( pSel!=0 );
      assert( pFrom->pTab==0 );
      sqlite3WalkSelect(pWalker, pSel);
      pFrom->pTab = pTab = sqlite3DbMallocZero(db, sizeof(Table));
      if( pTab==0 ) return WRC_Abort;
      pTab->nRef = 1;
      pTab->zName = sqlite3MPrintf(db, "sqlite_subquery_%p_", (void*)pTab);
      while( pSel->pPrior ){ pSel = pSel->pPrior; }
      selectColumnsFromExprList(pParse, pSel->pEList, &pTab->nCol, &pTab->aCol);
      pTab->iPKey = -1;
      pTab->nRowEst = 1000000;
      pTab->tabFlags |= TF_Ephemeral;
#endif
    }else{
      /* An ordinary table or view name in the FROM clause */
      assert( pFrom->pTab==0 );
      pFrom->pTab = pTab = sqlite3LocateTableItem(pParse, 0, pFrom);
      if( pTab==0 ) return WRC_Abort;
................................................................................
    for(i=0, pFrom=pTabList->a; i<pTabList->nSrc; i++, pFrom++){
      Table *pTab = pFrom->pTab;
      if( ALWAYS(pTab!=0) && (pTab->tabFlags & TF_Ephemeral)!=0 ){
        /* A sub-query in the FROM clause of a SELECT */
        Select *pSel = pFrom->pSelect;
        assert( pSel );
        while( pSel->pPrior ) pSel = pSel->pPrior;
        selectAddColumnTypeAndCollation(pParse, pTab->nCol, pTab->aCol, pSel);
      }
    }
  }
  return WRC_Continue;
}
#endif

................................................................................
      regAgg = 0;
    }
    if( pF->iDistinct>=0 ){
      addrNext = sqlite3VdbeMakeLabel(v);
      assert( nArg==1 );
      codeDistinct(pParse, pF->iDistinct, addrNext, 1, regAgg);
    }
    if( pF->pFunc->flags & SQLITE_FUNC_NEEDCOLL ){
      CollSeq *pColl = 0;
      struct ExprList_item *pItem;
      int j;
      assert( pList!=0 );  /* pList!=0 if pF->pFunc has NEEDCOLL */
      for(j=0, pItem=pList->a; !pColl && j<nArg; j++, pItem++){
        pColl = sqlite3ExprCollSeq(pParse, pItem->pExpr);
      }
................................................................................
        KeyInfo *pKeyInfo = 0;               /* Keyinfo for scanned index */
        Index *pBest = 0;                    /* Best index found so far */
        int iRoot = pTab->tnum;              /* Root page of scanned b-tree */

        sqlite3CodeVerifySchema(pParse, iDb);
        sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);

        /* Search for the index that has the least amount of columns. If
        ** there is such an index, and it has less columns than the table
        ** does, then we can assume that it consumes less space on disk and
        ** will therefore be cheaper to scan to determine the query result.
        ** In this case set iRoot to the root page number of the index b-tree
        ** and pKeyInfo to the KeyInfo structure required to navigate the
        ** index.
        **
        ** (2011-04-15) Do not do a full scan of an unordered index.


        **
        ** In practice the KeyInfo structure will not be used. It is only 
        ** passed to keep OP_OpenRead happy.
        */
        for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
          if( pIdx->bUnordered==0 && (!pBest || pIdx->nColumn<pBest->nColumn) ){




            pBest = pIdx;
          }
        }
        if( pBest && pBest->nColumn<pTab->nCol ){
          iRoot = pBest->tnum;
          pKeyInfo = sqlite3IndexKeyinfo(pParse, pBest);
        }

        /* Open a read-only cursor, execute the OP_Count, close the cursor. */
        sqlite3VdbeAddOp3(v, OP_OpenRead, iCsr, iRoot, iDb);
        if( pKeyInfo ){
................................................................................
        && pTab->pSchema==db->aDb[1].pSchema ){
    iDb = 1;
  }

  /* Ensure the table name matches database name and that the table exists */
  if( db->mallocFailed ) goto trigger_cleanup;
  assert( pTableName->nSrc==1 );
  if( sqlite3FixInit(&sFix, pParse, iDb, "trigger", pName) && 
      sqlite3FixSrcList(&sFix, pTableName) ){
    goto trigger_cleanup;
  }
  pTab = sqlite3SrcListLookup(pParse, pTableName);
  if( !pTab ){
    /* The table does not exist. */
    if( db->init.iDb==1 ){
      /* Ticket #3810.
................................................................................
  pTrig->step_list = pStepList;
  while( pStepList ){
    pStepList->pTrig = pTrig;
    pStepList = pStepList->pNext;
  }
  nameToken.z = pTrig->zName;
  nameToken.n = sqlite3Strlen30(nameToken.z);
  if( sqlite3FixInit(&sFix, pParse, iDb, "trigger", &nameToken) 
          && sqlite3FixTriggerStep(&sFix, pTrig->step_list) ){


    goto triggerfinish_cleanup;
  }

  /* if we are not initializing,
  ** build the sqlite_master entry
  */
  if( !db->init.busy ){
................................................................................
** on register iReg. This is used when an equivalent integer value is 
** stored in place of an 8-byte floating point value in order to save 
** space.
*/
SQLITE_PRIVATE void sqlite3ColumnDefault(Vdbe *v, Table *pTab, int i, int iReg){
  assert( pTab!=0 );
  if( !pTab->pSelect ){
    sqlite3_value *pValue;
    u8 enc = ENC(sqlite3VdbeDb(v));
    Column *pCol = &pTab->aCol[i];
    VdbeComment((v, "%s.%s", pTab->zName, pCol->zName));
    assert( i<pTab->nCol );
    sqlite3ValueFromExpr(sqlite3VdbeDb(v), pCol->pDflt, enc, 
                         pCol->affinity, &pValue);
    if( pValue ){
................................................................................

    /* Do constraint checks. */
    sqlite3GenerateConstraintChecks(pParse, pTab, iCur, regNewRowid,
        aRegIdx, (chngRowid?regOldRowid:0), 1, onError, addr, 0);

    /* Do FK constraint checks. */
    if( hasFK ){
      sqlite3FkCheck(pParse, pTab, regOldRowid, 0);
    }

    /* Delete the index entries associated with the current record.  */
    j1 = sqlite3VdbeAddOp3(v, OP_NotExists, iCur, 0, regOldRowid);
    sqlite3GenerateRowIndexDelete(pParse, pTab, iCur, aRegIdx);
  
    /* If changing the record number, delete the old record.  */
    if( hasFK || chngRowid ){
      sqlite3VdbeAddOp2(v, OP_Delete, iCur, 0);
    }
    sqlite3VdbeJumpHere(v, j1);

    if( hasFK ){
      sqlite3FkCheck(pParse, pTab, 0, regNewRowid);
    }
  
    /* Insert the new index entries and the new record. */
    sqlite3CompleteInsertion(pParse, pTab, iCur, regNewRowid, aRegIdx, 1, 0, 0);

    /* Do any ON CASCADE, SET NULL or SET DEFAULT operations required to
    ** handle rows (possibly in other tables) that refer via a foreign key
    ** to the row just updated. */ 
    if( hasFK ){
      sqlite3FkActions(pParse, pTab, pChanges, regOldRowid);
    }
  }

  /* Increment the row counter 
  */
  if( (db->flags & SQLITE_CountRows) && !pParse->pTriggerTab){
    sqlite3VdbeAddOp2(v, OP_AddImm, regRowCount, 1);
................................................................................
    }
  }

  return vacuumFinalize(db, pStmt, pzErrMsg);
}

/*
** The non-standard VACUUM command is used to clean up the database,
** collapse free space, etc.  It is modelled after the VACUUM command
** in PostgreSQL.
**
** In version 1.0.x of SQLite, the VACUUM command would call
** gdbm_reorganize() on all the database tables.  But beginning
** with 2.0.0, SQLite no longer uses GDBM so this command has
** become a no-op.




















*/
SQLITE_PRIVATE void sqlite3Vacuum(Parse *pParse){
  Vdbe *v = sqlite3GetVdbe(pParse);
  if( v ){
    sqlite3VdbeAddOp2(v, OP_Vacuum, 0, 0);
    sqlite3VdbeUsesBtree(v, 0);
  }
................................................................................
    return pDef;
  }
  *pNew = *pDef;
  pNew->zName = (char *)&pNew[1];
  memcpy(pNew->zName, pDef->zName, sqlite3Strlen30(pDef->zName)+1);
  pNew->xFunc = xFunc;
  pNew->pUserData = pArg;
  pNew->flags |= SQLITE_FUNC_EPHEM;
  return pNew;
}

/*
** Make sure virtual table pTab is contained in the pParse->apVirtualLock[]
** array so that an OP_VBegin will get generated for it.  Add pTab to the
** array if it is missing.  If pTab is already in the array, this routine
................................................................................
typedef struct WherePath WherePath;
typedef struct WhereTerm WhereTerm;
typedef struct WhereLoopBuilder WhereLoopBuilder;
typedef struct WhereScan WhereScan;
typedef struct WhereOrCost WhereOrCost;
typedef struct WhereOrSet WhereOrSet;

/*
** Cost X is tracked as 10*log2(X) stored in a 16-bit integer.  The
** maximum cost for ordinary tables is 64*(2**63) which becomes 6900.
** (Virtual tables can return a larger cost, but let's assume they do not.)
** So all costs can be stored in a 16-bit unsigned integer without risk
** of overflow.
**
** Costs are estimates, so no effort is made to compute 10*log2(X) exactly.
** Instead, a close estimate is used.  Any value of X<=1 is stored as 0.
** X=2 is 10.  X=3 is 16.  X=1000 is 99. etc.
**
** The tool/wherecosttest.c source file implements a command-line program
** that will convert WhereCosts to integers, convert integers to WhereCosts
** and do addition and multiplication on WhereCost values.  The wherecosttest
** command-line program is a useful utility to have around when working with
** this module.
*/
typedef unsigned short int WhereCost;

/*
** This object contains information needed to implement a single nested
** loop in WHERE clause.
**
** Contrast this object with WhereLoop.  This object describes the
** implementation of the loop.  WhereLoop describes the algorithm.
** This object contains a pointer to the WhereLoop algorithm as one of
................................................................................
        int addrInTop;         /* Top of the IN loop */
        u8 eEndLoopOp;         /* IN Loop terminator. OP_Next or OP_Prev */
      } *aInLoop;           /* Information about each nested IN operator */
    } in;                 /* Used when pWLoop->wsFlags&WHERE_IN_ABLE */
    Index *pCovidx;       /* Possible covering index for WHERE_MULTI_OR */
  } u;
  struct WhereLoop *pWLoop;  /* The selected WhereLoop object */

};

/*
** Each instance of this object represents an algorithm for evaluating one
** term of a join.  Every term of the FROM clause will have at least
** one corresponding WhereLoop object (unless INDEXED BY constraints
** prevent a query solution - which is an error) and many terms of the
................................................................................
  Bitmask prereq;       /* Bitmask of other loops that must run first */
  Bitmask maskSelf;     /* Bitmask identifying table iTab */
#ifdef SQLITE_DEBUG
  char cId;             /* Symbolic ID of this loop for debugging use */
#endif
  u8 iTab;              /* Position in FROM clause of table for this loop */
  u8 iSortIdx;          /* Sorting index number.  0==None */
  WhereCost rSetup;     /* One-time setup cost (ex: create transient index) */
  WhereCost rRun;       /* Cost of running each loop */
  WhereCost nOut;       /* Estimated number of output rows */
  union {
    struct {               /* Information for internal btree tables */
      int nEq;               /* Number of equality constraints */
      Index *pIndex;         /* Index used, or NULL */
    } btree;
    struct {               /* Information for virtual tables */
      int idxNum;            /* Index number */
................................................................................

/* This object holds the prerequisites and the cost of running a
** subquery on one operand of an OR operator in the WHERE clause.
** See WhereOrSet for additional information 
*/
struct WhereOrCost {
  Bitmask prereq;     /* Prerequisites */
  WhereCost rRun;     /* Cost of running this subquery */
  WhereCost nOut;     /* Number of outputs for this subquery */
};

/* The WhereOrSet object holds a set of possible WhereOrCosts that
** correspond to the subquery(s) of OR-clause processing.  Only the
** best N_OR_COST elements are retained.
*/
#define N_OR_COST 3
................................................................................
static int whereLoopResize(sqlite3*, WhereLoop*, int);

/*
** Each instance of this object holds a sequence of WhereLoop objects
** that implement some or all of a query plan.
**
** Think of each WhereLoop object as a node in a graph with arcs
** showing dependences and costs for travelling between nodes.  (That is
** not a completely accurate description because WhereLoop costs are a
** vector, not a scalar, and because dependences are many-to-one, not
** one-to-one as are graph nodes.  But it is a useful visualization aid.)
** Then a WherePath object is a path through the graph that visits some
** or all of the WhereLoop objects once.
**
** The "solver" works by creating the N best WherePath objects of length
** 1.  Then using those as a basis to compute the N best WherePath objects
** of length 2.  And so forth until the length of WherePaths equals the
** number of nodes in the FROM clause.  The best (lowest cost) WherePath
** at the end is the choosen query plan.
*/
struct WherePath {
  Bitmask maskLoop;     /* Bitmask of all WhereLoop objects in this path */
  Bitmask revLoop;      /* aLoop[]s that should be reversed for ORDER BY */
  WhereCost nRow;       /* Estimated number of rows generated by this path */
  WhereCost rCost;      /* Total cost of this path */
  u8 isOrdered;         /* True if this path satisfies ORDER BY */
  u8 isOrderedValid;    /* True if the isOrdered field is valid */
  WhereLoop **aLoop;    /* Array of WhereLoop objects implementing this path */
};

/*
** The query generator uses an array of instances of this structure to
................................................................................
  int iParent;            /* Disable pWC->a[iParent] when this term disabled */
  int leftCursor;         /* Cursor number of X in "X <op> <expr>" */
  union {
    int leftColumn;         /* Column number of X in "X <op> <expr>" */
    WhereOrInfo *pOrInfo;   /* Extra information if (eOperator & WO_OR)!=0 */
    WhereAndInfo *pAndInfo; /* Extra information if (eOperator& WO_AND)!=0 */
  } u;

  u16 eOperator;          /* A WO_xx value describing <op> */
  u8 wtFlags;             /* TERM_xxx bit flags.  See below */
  u8 nChild;              /* Number of children that must disable us */
  WhereClause *pWC;       /* The clause this term is part of */
  Bitmask prereqRight;    /* Bitmask of tables used by pExpr->pRight */
  Bitmask prereqAll;      /* Bitmask of tables referenced by pExpr */
};
................................................................................
#define TERM_DYNAMIC    0x01   /* Need to call sqlite3ExprDelete(db, pExpr) */
#define TERM_VIRTUAL    0x02   /* Added by the optimizer.  Do not code */
#define TERM_CODED      0x04   /* This term is already coded */
#define TERM_COPIED     0x08   /* Has a child */
#define TERM_ORINFO     0x10   /* Need to free the WhereTerm.u.pOrInfo object */
#define TERM_ANDINFO    0x20   /* Need to free the WhereTerm.u.pAndInfo obj */
#define TERM_OR_OK      0x40   /* Used during OR-clause processing */
#ifdef SQLITE_ENABLE_STAT3
#  define TERM_VNULL    0x80   /* Manufactured x>NULL or x<=NULL term */
#else
#  define TERM_VNULL    0x00   /* Disabled if not using stat3 */
#endif

/*
** An instance of the WhereScan object is used as an iterator for locating
................................................................................
*/
struct WhereLoopBuilder {
  WhereInfo *pWInfo;        /* Information about this WHERE */
  WhereClause *pWC;         /* WHERE clause terms */
  ExprList *pOrderBy;       /* ORDER BY clause */
  WhereLoop *pNew;          /* Template WhereLoop */
  WhereOrSet *pOrSet;       /* Record best loops here, if not NULL */




};

/*
** The WHERE clause processing routine has two halves.  The
** first part does the start of the WHERE loop and the second
** half does the tail of the WHERE loop.  An instance of
** this structure is returned by the first half and passed
................................................................................
struct WhereInfo {
  Parse *pParse;            /* Parsing and code generating context */
  SrcList *pTabList;        /* List of tables in the join */
  ExprList *pOrderBy;       /* The ORDER BY clause or NULL */
  ExprList *pResultSet;     /* Result set. DISTINCT operates on these */
  WhereLoop *pLoops;        /* List of all WhereLoop objects */
  Bitmask revMask;          /* Mask of ORDER BY terms that need reversing */
  WhereCost nRowOut;        /* Estimated number of output rows */
  u16 wctrlFlags;           /* Flags originally passed to sqlite3WhereBegin() */
  u8 bOBSat;                /* ORDER BY satisfied by indices */
  u8 okOnePass;             /* Ok to use one-pass algorithm for UPDATE/DELETE */
  u8 untestedTerms;         /* Not all WHERE terms resolved by outer loop */
  u8 eDistinct;             /* One of the WHERE_DISTINCT_* values below */
  u8 nLevel;                /* Number of nested loop */
  int iTop;                 /* The very beginning of the WHERE loop */
................................................................................
#define WHERE_INDEXED      0x00000200  /* WhereLoop.u.btree.pIndex is valid */
#define WHERE_VIRTUALTABLE 0x00000400  /* WhereLoop.u.vtab is valid */
#define WHERE_IN_ABLE      0x00000800  /* Able to support an IN operator */
#define WHERE_ONEROW       0x00001000  /* Selects no more than one row */
#define WHERE_MULTI_OR     0x00002000  /* OR using multiple indices */
#define WHERE_AUTO_INDEX   0x00004000  /* Uses an ephemeral index */


/* Convert a WhereCost value (10 times log2(X)) into its integer value X.
** A rough approximation is used.  The value returned is not exact.
*/
static u64 whereCostToInt(WhereCost x){
  u64 n;
  if( x<10 ) return 1;
  n = x%10;
  x /= 10;
  if( n>=5 ) n -= 2;
  else if( n>=1 ) n -= 1;
  if( x>=3 ) return (n+8)<<(x-3);
  return (n+8)>>(3-x);
}

/*
** Return the estimated number of output rows from a WHERE clause
*/
SQLITE_PRIVATE u64 sqlite3WhereOutputRowCount(WhereInfo *pWInfo){
  return whereCostToInt(pWInfo->nRowOut);
}

/*
** Return one of the WHERE_DISTINCT_xxxxx values to indicate how this
** WHERE clause returns outputs for DISTINCT processing.
*/
SQLITE_PRIVATE int sqlite3WhereIsDistinct(WhereInfo *pWInfo){
................................................................................
** The new entry might overwrite an existing entry, or it might be
** appended, or it might be discarded.  Do whatever is the right thing
** so that pSet keeps the N_OR_COST best entries seen so far.
*/
static int whereOrInsert(
  WhereOrSet *pSet,      /* The WhereOrSet to be updated */
  Bitmask prereq,        /* Prerequisites of the new entry */
  WhereCost rRun,        /* Run-cost of the new entry */
  WhereCost nOut         /* Number of outputs for the new entry */
){
  u16 i;
  WhereOrCost *p;
  for(i=pSet->n, p=pSet->a; i>0; i--, p++){
    if( rRun<=p->rRun && (prereq & p->prereq)==prereq ){
      goto whereOrInsert_done;
    }
................................................................................
    memcpy(pWC->a, pOld, sizeof(pWC->a[0])*pWC->nTerm);
    if( pOld!=pWC->aStatic ){
      sqlite3DbFree(db, pOld);
    }
    pWC->nSlot = sqlite3DbMallocSize(db, pWC->a)/sizeof(pWC->a[0]);
  }
  pTerm = &pWC->a[idx = pWC->nTerm++];





  pTerm->pExpr = sqlite3ExprSkipCollate(p);
  pTerm->wtFlags = wtFlags;
  pTerm->pWC = pWC;
  pTerm->iParent = -1;
  return idx;
}

................................................................................
#endif /* SQLITE_OMIT_VIRTUALTABLE */

/*
** If the pBase expression originated in the ON or USING clause of
** a join, then transfer the appropriate markings over to derived.
*/
static void transferJoinMarkings(Expr *pDerived, Expr *pBase){

  pDerived->flags |= pBase->flags & EP_FromJoin;
  pDerived->iRightJoinTable = pBase->iRightJoinTable;

}

#if !defined(SQLITE_OMIT_OR_OPTIMIZATION) && !defined(SQLITE_OMIT_SUBQUERY)
/*
** Analyze a term that consists of two or more OR-connected
** subterms.  So in:
**
................................................................................
    assert( pList->nExpr==2 );
    for(i=0; i<2; i++){
      Expr *pNewExpr;
      int idxNew;
      pNewExpr = sqlite3PExpr(pParse, ops[i], 
                             sqlite3ExprDup(db, pExpr->pLeft, 0),
                             sqlite3ExprDup(db, pList->a[i].pExpr, 0), 0);

      idxNew = whereClauseInsert(pWC, pNewExpr, TERM_VIRTUAL|TERM_DYNAMIC);
      testcase( idxNew==0 );
      exprAnalyze(pSrc, pWC, idxNew);
      pTerm = &pWC->a[idxTerm];
      pWC->a[idxNew].iParent = idxTerm;
    }
    pTerm->nChild = 2;
................................................................................
    }
    sCollSeqName.z = noCase ? "NOCASE" : "BINARY";
    sCollSeqName.n = 6;
    pNewExpr1 = sqlite3ExprDup(db, pLeft, 0);
    pNewExpr1 = sqlite3PExpr(pParse, TK_GE, 
           sqlite3ExprAddCollateToken(pParse,pNewExpr1,&sCollSeqName),
           pStr1, 0);

    idxNew1 = whereClauseInsert(pWC, pNewExpr1, TERM_VIRTUAL|TERM_DYNAMIC);
    testcase( idxNew1==0 );
    exprAnalyze(pSrc, pWC, idxNew1);
    pNewExpr2 = sqlite3ExprDup(db, pLeft, 0);
    pNewExpr2 = sqlite3PExpr(pParse, TK_LT,
           sqlite3ExprAddCollateToken(pParse,pNewExpr2,&sCollSeqName),
           pStr2, 0);

    idxNew2 = whereClauseInsert(pWC, pNewExpr2, TERM_VIRTUAL|TERM_DYNAMIC);
    testcase( idxNew2==0 );
    exprAnalyze(pSrc, pWC, idxNew2);
    pTerm = &pWC->a[idxTerm];
    if( isComplete ){
      pWC->a[idxNew1].iParent = idxTerm;
      pWC->a[idxNew2].iParent = idxTerm;
................................................................................
      pTerm->nChild = 1;
      pTerm->wtFlags |= TERM_COPIED;
      pNewTerm->prereqAll = pTerm->prereqAll;
    }
  }
#endif /* SQLITE_OMIT_VIRTUALTABLE */

#ifdef SQLITE_ENABLE_STAT3
  /* When sqlite_stat3 histogram data is available an operator of the
  ** form "x IS NOT NULL" can sometimes be evaluated more efficiently
  ** as "x>NULL" if x is not an INTEGER PRIMARY KEY.  So construct a
  ** virtual term of that form.
  **
  ** Note that the virtual term must be tagged with TERM_VNULL.  This
  ** TERM_VNULL tag will suppress the not-null check at the beginning
................................................................................
      pNewTerm->iParent = idxTerm;
      pTerm = &pWC->a[idxTerm];
      pTerm->nChild = 1;
      pTerm->wtFlags |= TERM_COPIED;
      pNewTerm->prereqAll = pTerm->prereqAll;
    }
  }
#endif /* SQLITE_ENABLE_STAT */

  /* Prevent ON clause terms of a LEFT JOIN from being used to drive
  ** an index for tables to the left of the join.
  */
  pTerm->prereqRight |= extraRight;
}

................................................................................
      return 1;
    }
  }

  return 0;
}

/* 
** Find (an approximate) sum of two WhereCosts.  This computation is
** not a simple "+" operator because WhereCost is stored as a logarithmic
** value.
** 
*/
static WhereCost whereCostAdd(WhereCost a, WhereCost b){
  static const unsigned char x[] = {
     10, 10,                         /* 0,1 */
      9, 9,                          /* 2,3 */
      8, 8,                          /* 4,5 */
      7, 7, 7,                       /* 6,7,8 */
      6, 6, 6,                       /* 9,10,11 */
      5, 5, 5,                       /* 12-14 */
      4, 4, 4, 4,                    /* 15-18 */
      3, 3, 3, 3, 3, 3,              /* 19-24 */
      2, 2, 2, 2, 2, 2, 2,           /* 25-31 */
  };
  if( a>=b ){
    if( a>b+49 ) return a;
    if( a>b+31 ) return a+1;
    return a+x[a-b];
  }else{
    if( b>a+49 ) return b;
    if( b>a+31 ) return b+1;
    return b+x[b-a];
  }
}

/*
** Convert an integer into a WhereCost.  In other words, compute a
** good approximatation for 10*log2(x).
*/
static WhereCost whereCost(tRowcnt x){
  static WhereCost a[] = { 0, 2, 3, 5, 6, 7, 8, 9 };
  WhereCost y = 40;
  if( x<8 ){
    if( x<2 ) return 0;
    while( x<8 ){  y -= 10; x <<= 1; }
  }else{
    while( x>255 ){ y += 40; x >>= 4; }
    while( x>15 ){  y += 10; x >>= 1; }
  }
  return a[x&7] + y - 10;
}

#ifndef SQLITE_OMIT_VIRTUALTABLE
/*
** Convert a double (as received from xBestIndex of a virtual table)
** into a WhereCost.  In other words, compute an approximation for
** 10*log2(x).
*/
static WhereCost whereCostFromDouble(double x){
  u64 a;
  WhereCost e;
  assert( sizeof(x)==8 && sizeof(a)==8 );
  if( x<=1 ) return 0;
  if( x<=2000000000 ) return whereCost((tRowcnt)x);
  memcpy(&a, &x, 8);
  e = (a>>52) - 1022;
  return e*10;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */

/*
** Estimate the logarithm of the input value to base 2.
*/
static WhereCost estLog(WhereCost N){
  WhereCost x = whereCost(N);


  return x>33 ? x - 33 : 0;
}

/*
** Two routines for printing the content of an sqlite3_index_info
** structure.  Used for testing and debugging only.  If neither
** SQLITE_TEST or SQLITE_DEBUG are defined, then these routines
................................................................................
  }

  return pParse->nErr;
}
#endif /* !defined(SQLITE_OMIT_VIRTUALTABLE) */


#ifdef SQLITE_ENABLE_STAT3
/*
** Estimate the location of a particular key among all keys in an
** index.  Store the results in aStat as follows:
**
**    aStat[0]      Est. number of rows less than pVal
**    aStat[1]      Est. number of rows equal to pVal
**
** Return SQLITE_OK on success.
*/
static int whereKeyStats(
  Parse *pParse,              /* Database connection */
  Index *pIdx,                /* Index to consider domain of */
  sqlite3_value *pVal,        /* Value to consider */
  int roundUp,                /* Round up if true.  Round down if false */
  tRowcnt *aStat              /* OUT: stats written here */
){
  tRowcnt n;
  IndexSample *aSample;

  int i, eType;
  int isEq = 0;
  i64 v;
  double r, rS;

  assert( roundUp==0 || roundUp==1 );





  assert( pIdx->nSample>0 );
  if( pVal==0 ) return SQLITE_ERROR;
  n = pIdx->aiRowEst[0];
  aSample = pIdx->aSample;
  eType = sqlite3_value_type(pVal);

  if( eType==SQLITE_INTEGER ){
    v = sqlite3_value_int64(pVal);

    r = (i64)v;
    for(i=0; i<pIdx->nSample; i++){
      if( aSample[i].eType==SQLITE_NULL ) continue;
      if( aSample[i].eType>=SQLITE_TEXT ) break;
      if( aSample[i].eType==SQLITE_INTEGER ){
        if( aSample[i].u.i>=v ){
          isEq = aSample[i].u.i==v;
          break;
        }
      }else{
        assert( aSample[i].eType==SQLITE_FLOAT );
        if( aSample[i].u.r>=r ){
          isEq = aSample[i].u.r==r;
          break;
        }
      }
    }
  }else if( eType==SQLITE_FLOAT ){
    r = sqlite3_value_double(pVal);
    for(i=0; i<pIdx->nSample; i++){
      if( aSample[i].eType==SQLITE_NULL ) continue;
      if( aSample[i].eType>=SQLITE_TEXT ) break;
      if( aSample[i].eType==SQLITE_FLOAT ){
        rS = aSample[i].u.r;
      }else{
        rS = aSample[i].u.i;
      }
      if( rS>=r ){
        isEq = rS==r;
        break;
      }
    }
  }else if( eType==SQLITE_NULL ){
    i = 0;
    if( aSample[0].eType==SQLITE_NULL ) isEq = 1;
  }else{
    assert( eType==SQLITE_TEXT || eType==SQLITE_BLOB );
    for(i=0; i<pIdx->nSample; i++){
      if( aSample[i].eType==SQLITE_TEXT || aSample[i].eType==SQLITE_BLOB ){
        break;
      }

    }






    if( i<pIdx->nSample ){      

      sqlite3 *db = pParse->db;
      CollSeq *pColl;
      const u8 *z;
      if( eType==SQLITE_BLOB ){
        z = (const u8 *)sqlite3_value_blob(pVal);
        pColl = db->pDfltColl;
        assert( pColl->enc==SQLITE_UTF8 );
      }else{
        pColl = sqlite3GetCollSeq(pParse, SQLITE_UTF8, 0, *pIdx->azColl);
        /* If the collating sequence was unavailable, we should have failed
        ** long ago and never reached this point.  But we'll check just to
        ** be doubly sure. */
        if( NEVER(pColl==0) ) return SQLITE_ERROR;
        z = (const u8 *)sqlite3ValueText(pVal, pColl->enc);
        if( !z ){
          return SQLITE_NOMEM;
        }
        assert( z && pColl && pColl->xCmp );
      }
      n = sqlite3ValueBytes(pVal, pColl->enc);
  


      for(; i<pIdx->nSample; i++){
        int c;
        int eSampletype = aSample[i].eType;
        if( eSampletype<eType ) continue;
        if( eSampletype!=eType ) break;
#ifndef SQLITE_OMIT_UTF16
        if( pColl->enc!=SQLITE_UTF8 ){
          int nSample;
          char *zSample = sqlite3Utf8to16(
              db, pColl->enc, aSample[i].u.z, aSample[i].nByte, &nSample
          );
          if( !zSample ){

            assert( db->mallocFailed );
            return SQLITE_NOMEM;



          }
          c = pColl->xCmp(pColl->pUser, nSample, zSample, n, z);
          sqlite3DbFree(db, zSample);
        }else
#endif

        {
          c = pColl->xCmp(pColl->pUser, aSample[i].nByte, aSample[i].u.z, n, z);
        }
        if( c>=0 ){
          if( c==0 ) isEq = 1;
          break;
        }
      }
    }
  }

  /* At this point, aSample[i] is the first sample that is greater than
  ** or equal to pVal.  Or if i==pIdx->nSample, then all samples are less
  ** than pVal.  If aSample[i]==pVal, then isEq==1.
  */
  if( isEq ){
    assert( i<pIdx->nSample );

    aStat[0] = aSample[i].nLt;
    aStat[1] = aSample[i].nEq;
  }else{
    tRowcnt iLower, iUpper, iGap;
    if( i==0 ){
      iLower = 0;
      iUpper = aSample[0].nLt;
    }else{
      iUpper = i>=pIdx->nSample ? n : aSample[i].nLt;
      iLower = aSample[i-1].nEq + aSample[i-1].nLt;
    }
    aStat[1] = pIdx->avgEq;
    if( iLower>=iUpper ){
      iGap = 0;
    }else{
      iGap = iUpper - iLower;
    }
    if( roundUp ){
      iGap = (iGap*2)/3;
    }else{
      iGap = iGap/3;
    }
    aStat[0] = iLower + iGap;
  }
  return SQLITE_OK;
}
#endif /* SQLITE_ENABLE_STAT3 */

/*
** If expression pExpr represents a literal value, set *pp to point to
** an sqlite3_value structure containing the same value, with affinity
** aff applied to it, before returning. It is the responsibility of the 
** caller to eventually release this structure by passing it to 
** sqlite3ValueFree().
**
** If the current parse is a recompile (sqlite3Reprepare()) and pExpr
** is an SQL variable that currently has a non-NULL value bound to it,
** create an sqlite3_value structure containing this value, again with
** affinity aff applied to it, instead.
**
** If neither of the above apply, set *pp to NULL.
**
** If an error occurs, return an error code. Otherwise, SQLITE_OK.
*/
#ifdef SQLITE_ENABLE_STAT3
static int valueFromExpr(
  Parse *pParse, 
  Expr *pExpr, 
  u8 aff, 
  sqlite3_value **pp
){
  if( pExpr->op==TK_VARIABLE
   || (pExpr->op==TK_REGISTER && pExpr->op2==TK_VARIABLE)
  ){
    int iVar = pExpr->iColumn;
    sqlite3VdbeSetVarmask(pParse->pVdbe, iVar);
    *pp = sqlite3VdbeGetBoundValue(pParse->pReprepare, iVar, aff);
    return SQLITE_OK;
  }
  return sqlite3ValueFromExpr(pParse->db, pExpr, SQLITE_UTF8, aff, pp);
}
#endif

/*
** This function is used to estimate the number of rows that will be visited
** by scanning an index for a range of values. The range may have an upper
** bound, a lower bound, or both. The WHERE clause terms that set the upper
** and lower bounds are represented by pLower and pUpper respectively. For
** example, assuming that index p is on t1(a):
................................................................................
**                    |_____|   |_____|
**                       |         |
**                     pLower    pUpper
**
** If either of the upper or lower bound is not present, then NULL is passed in
** place of the corresponding WhereTerm.
**
** The nEq parameter is passed the index of the index column subject to the
** range constraint. Or, equivalently, the number of equality constraints
** optimized by the proposed index scan. For example, assuming index p is
** on t1(a, b), and the SQL query is:
**
**   ... FROM t1 WHERE a = ? AND b > ? AND b < ? ...
**
** then nEq should be passed the value 1 (as the range restricted column,
** b, is the second left-most column of the index). Or, if the query is:
**
**   ... FROM t1 WHERE a > ? AND a < ? ...
**
** then nEq should be passed 0.
**
** The returned value is an integer divisor to reduce the estimated
** search space.  A return value of 1 means that range constraints are
** no help at all.  A return value of 2 means range constraints are
** expected to reduce the search space by half.  And so forth...

**
** In the absence of sqlite_stat3 ANALYZE data, each range inequality
** reduces the search space by a factor of 4.  Hence a single constraint (x>?)
** results in a return of 4 and a range constraint (x>? AND x<?) results
** in a return of 16.

*/
static int whereRangeScanEst(
  Parse *pParse,       /* Parsing & code generating context */
  Index *p,            /* The index containing the range-compared column; "x" */
  int nEq,             /* index into p->aCol[] of the range-compared column */
  WhereTerm *pLower,   /* Lower bound on the range. ex: "x>123" Might be NULL */
  WhereTerm *pUpper,   /* Upper bound on the range. ex: "x<455" Might be NULL */
  WhereCost *pRangeDiv /* OUT: Reduce search space by this divisor */

){
  int rc = SQLITE_OK;



#ifdef SQLITE_ENABLE_STAT3






  if( nEq==0 && p->nSample && OptimizationEnabled(pParse->db, SQLITE_Stat3) ){
    sqlite3_value *pRangeVal;


    tRowcnt iLower = 0;



















    tRowcnt iUpper = p->aiRowEst[0];
    tRowcnt a[2];




    u8 aff = p->pTable->aCol[p->aiColumn[0]].affinity;














    if( pLower ){

      Expr *pExpr = pLower->pExpr->pRight;
      rc = valueFromExpr(pParse, pExpr, aff, &pRangeVal);
      assert( (pLower->eOperator & (WO_GT|WO_GE))!=0 );

      if( rc==SQLITE_OK

       && whereKeyStats(pParse, p, pRangeVal, 0, a)==SQLITE_OK
      ){
        iLower = a[0];
        if( (pLower->eOperator & WO_GT)!=0 ) iLower += a[1];


      }
      sqlite3ValueFree(pRangeVal);
    }


    if( rc==SQLITE_OK && pUpper ){

      Expr *pExpr = pUpper->pExpr->pRight;
      rc = valueFromExpr(pParse, pExpr, aff, &pRangeVal);
      assert( (pUpper->eOperator & (WO_LT|WO_LE))!=0 );

      if( rc==SQLITE_OK

       && whereKeyStats(pParse, p, pRangeVal, 1, a)==SQLITE_OK
      ){
        iUpper = a[0];
        if( (pUpper->eOperator & WO_LE)!=0 ) iUpper += a[1];


      }
      sqlite3ValueFree(pRangeVal);
    }


    if( rc==SQLITE_OK ){
      WhereCost iBase = whereCost(p->aiRowEst[0]);
      if( iUpper>iLower ){
        iBase -= whereCost(iUpper - iLower);


      }
      *pRangeDiv = iBase;




      WHERETRACE(0x100, ("range scan regions: %u..%u  div=%d\n",
                         (u32)iLower, (u32)iUpper, *pRangeDiv));
      return SQLITE_OK;
    }
  }
#else
  UNUSED_PARAMETER(pParse);
  UNUSED_PARAMETER(p);
  UNUSED_PARAMETER(nEq);
#endif
  assert( pLower || pUpper );
  *pRangeDiv = 0;
  /* TUNING:  Each inequality constraint reduces the search space 4-fold.
  ** A BETWEEN operator, therefore, reduces the search space 16-fold */

  if( pLower && (pLower->wtFlags & TERM_VNULL)==0 ){

    *pRangeDiv += 20;  assert( 20==whereCost(4) );
  }
  if( pUpper ){
    *pRangeDiv += 20;  assert( 20==whereCost(4) );

  }



  return rc;
}

#ifdef SQLITE_ENABLE_STAT3
/*
** Estimate the number of rows that will be returned based on
** an equality constraint x=VALUE and where that VALUE occurs in
** the histogram data.  This only works when x is the left-most
** column of an index and sqlite_stat3 histogram data is available
** for that index.  When pExpr==NULL that means the constraint is
** "x IS NULL" instead of "x=VALUE".
................................................................................
** This routine can fail if it is unable to load a collating sequence
** required for string comparison, or if unable to allocate memory
** for a UTF conversion required for comparison.  The error is stored
** in the pParse structure.
*/
static int whereEqualScanEst(
  Parse *pParse,       /* Parsing & code generating context */
  Index *p,            /* The index whose left-most column is pTerm */
  Expr *pExpr,         /* Expression for VALUE in the x=VALUE constraint */
  tRowcnt *pnRow       /* Write the revised row estimate here */
){
  sqlite3_value *pRhs = 0;  /* VALUE on right-hand side of pTerm */


  u8 aff;                   /* Column affinity */
  int rc;                   /* Subfunction return code */
  tRowcnt a[2];             /* Statistics */




  assert( p->aSample!=0 );
  assert( p->nSample>0 );
  aff = p->pTable->aCol[p->aiColumn[0]].affinity;
  if( pExpr ){
    rc = valueFromExpr(pParse, pExpr, aff, &pRhs);
    if( rc ) goto whereEqualScanEst_cancel;
  }else{

    pRhs = sqlite3ValueNew(pParse->db);



  }












  if( pRhs==0 ) return SQLITE_NOTFOUND;


  rc = whereKeyStats(pParse, p, pRhs, 0, a);
  if( rc==SQLITE_OK ){
    WHERETRACE(0x100,("equality scan regions: %d\n", (int)a[1]));
    *pnRow = a[1];
  }
whereEqualScanEst_cancel:
  sqlite3ValueFree(pRhs);
  return rc;
}
#endif /* defined(SQLITE_ENABLE_STAT3) */

#ifdef SQLITE_ENABLE_STAT3
/*
** Estimate the number of rows that will be returned based on
** an IN constraint where the right-hand side of the IN operator
** is a list of values.  Example:
**
**        WHERE x IN (1,2,3,4)
**
................................................................................
** This routine can fail if it is unable to load a collating sequence
** required for string comparison, or if unable to allocate memory
** for a UTF conversion required for comparison.  The error is stored
** in the pParse structure.
*/
static int whereInScanEst(
  Parse *pParse,       /* Parsing & code generating context */
  Index *p,            /* The index whose left-most column is pTerm */
  ExprList *pList,     /* The value list on the RHS of "x IN (v1,v2,v3,...)" */
  tRowcnt *pnRow       /* Write the revised row estimate here */
){


  int rc = SQLITE_OK;     /* Subfunction return code */
  tRowcnt nEst;           /* Number of rows for a single term */
  tRowcnt nRowEst = 0;    /* New estimate of the number of rows */
  int i;                  /* Loop counter */

  assert( p->aSample!=0 );
  for(i=0; rc==SQLITE_OK && i<pList->nExpr; i++){
    nEst = p->aiRowEst[0];
    rc = whereEqualScanEst(pParse, p, pList->a[i].pExpr, &nEst);
    nRowEst += nEst;

  }

  if( rc==SQLITE_OK ){
    if( nRowEst > p->aiRowEst[0] ) nRowEst = p->aiRowEst[0];
    *pnRow = nRowEst;
    WHERETRACE(0x100,("IN row estimate: est=%g\n", nRowEst));
  }

  return rc;
}
#endif /* defined(SQLITE_ENABLE_STAT3) */

/*
** Disable a term in the WHERE clause.  Except, do not disable the term
** if it controls a LEFT OUTER JOIN and it did not originate in the ON
** or USING clause of that join.
**
** Consider the term t2.z='ok' in the following queries:
................................................................................
** as we can without disabling too much.  If we disabled in (1), we'd get
** the wrong answer.  See ticket #813.
*/
static void disableTerm(WhereLevel *pLevel, WhereTerm *pTerm){
  if( pTerm
      && (pTerm->wtFlags & TERM_CODED)==0
      && (pLevel->iLeftJoin==0 || ExprHasProperty(pTerm->pExpr, EP_FromJoin))

  ){
    pTerm->wtFlags |= TERM_CODED;
    if( pTerm->iParent>=0 ){
      WhereTerm *pOther = &pTerm->pWC->a[pTerm->iParent];
      if( (--pOther->nChild)==0 ){
        disableTerm(pLevel, pOther);
      }
................................................................................
  zAff = sqlite3DbStrDup(pParse->db, sqlite3IndexAffinityStr(v, pIdx));
  if( !zAff ){
    pParse->db->mallocFailed = 1;
  }

  /* Evaluate the equality constraints
  */
  assert( zAff==0 || strlen(zAff)>=nEq );
  for(j=0; j<nEq; j++){
    int r1;
    pTerm = pLoop->aLTerm[j];
    assert( pTerm!=0 );
    /* The following true for indices with redundant columns. 
    ** Ex: CREATE INDEX i1 ON t1(a,b,a); SELECT * FROM t1 WHERE a=0 AND b=0; */
    testcase( (pTerm->wtFlags & TERM_CODED)!=0 );
................................................................................
  sqlite3 *db;                    /* Database connection */
  Vdbe *v;                        /* The prepared stmt under constructions */
  struct SrcList_item *pTabItem;  /* FROM clause term being coded */
  int addrBrk;                    /* Jump here to break out of the loop */
  int addrCont;                   /* Jump here to continue with next cycle */
  int iRowidReg = 0;        /* Rowid is stored in this register, if not zero */
  int iReleaseReg = 0;      /* Temp register to free before returning */
  Bitmask newNotReady;      /* Return value */

  pParse = pWInfo->pParse;
  v = pParse->pVdbe;
  pWC = &pWInfo->sWC;
  db = pParse->db;
  pLevel = &pWInfo->a[iLevel];
  pLoop = pLevel->pWLoop;
  pTabItem = &pWInfo->pTabList->a[pLevel->iFrom];
  iCur = pTabItem->iCursor;

  bRev = (pWInfo->revMask>>iLevel)&1;
  omitTable = (pLoop->wsFlags & WHERE_IDX_ONLY)!=0 
           && (pWInfo->wctrlFlags & WHERE_FORCE_TABLE)==0;
  VdbeNoopComment((v, "Begin Join Loop %d", iLevel));

  /* Create labels for the "break" and "continue" instructions
  ** for the current loop.  Jump to addrBrk to break out of a loop.
................................................................................
    static const u8 aStart[] = { OP_Rewind, OP_Last };
    assert( bRev==0 || bRev==1 );
    pLevel->op = aStep[bRev];
    pLevel->p1 = iCur;
    pLevel->p2 = 1 + sqlite3VdbeAddOp2(v, aStart[bRev], iCur, addrBrk);
    pLevel->p5 = SQLITE_STMTSTATUS_FULLSCAN_STEP;
  }
  newNotReady = notReady & ~getMask(&pWInfo->sMaskSet, iCur);

  /* Insert code to test every subexpression that can be completely
  ** computed using the current set of tables.
  */
  for(pTerm=pWC->a, j=pWC->nTerm; j>0; j--, pTerm++){
    Expr *pE;
    testcase( pTerm->wtFlags & TERM_VIRTUAL );
    testcase( pTerm->wtFlags & TERM_CODED );
    if( pTerm->wtFlags & (TERM_VIRTUAL|TERM_CODED) ) continue;
    if( (pTerm->prereqAll & newNotReady)!=0 ){
      testcase( pWInfo->untestedTerms==0
               && (pWInfo->wctrlFlags & WHERE_ONETABLE_ONLY)!=0 );
      pWInfo->untestedTerms = 1;
      continue;
    }
    pE = pTerm->pExpr;
    assert( pE!=0 );
................................................................................
    WhereTerm *pAlt;
    if( pTerm->wtFlags & (TERM_VIRTUAL|TERM_CODED) ) continue;
    if( pTerm->eOperator!=(WO_EQUIV|WO_EQ) ) continue;
    if( pTerm->leftCursor!=iCur ) continue;
    if( pLevel->iLeftJoin ) continue;
    pE = pTerm->pExpr;
    assert( !ExprHasProperty(pE, EP_FromJoin) );
    assert( (pTerm->prereqRight & newNotReady)!=0 );
    pAlt = findTerm(pWC, iCur, pTerm->u.leftColumn, notReady, WO_EQ|WO_IN, 0);
    if( pAlt==0 ) continue;
    if( pAlt->wtFlags & (TERM_CODED) ) continue;
    testcase( pAlt->eOperator & WO_EQ );
    testcase( pAlt->eOperator & WO_IN );
    VdbeNoopComment((v, "begin transitive constraint"));
    pEAlt = sqlite3StackAllocRaw(db, sizeof(*pEAlt));
................................................................................
    sqlite3VdbeAddOp2(v, OP_Integer, 1, pLevel->iLeftJoin);
    VdbeComment((v, "record LEFT JOIN hit"));
    sqlite3ExprCacheClear(pParse);
    for(pTerm=pWC->a, j=0; j<pWC->nTerm; j++, pTerm++){
      testcase( pTerm->wtFlags & TERM_VIRTUAL );
      testcase( pTerm->wtFlags & TERM_CODED );
      if( pTerm->wtFlags & (TERM_VIRTUAL|TERM_CODED) ) continue;
      if( (pTerm->prereqAll & newNotReady)!=0 ){
        assert( pWInfo->untestedTerms );
        continue;
      }
      assert( pTerm->pExpr );
      sqlite3ExprIfFalse(pParse, pTerm->pExpr, addrCont, SQLITE_JUMPIFNULL);
      pTerm->wtFlags |= TERM_CODED;
    }
  }
  sqlite3ReleaseTempReg(pParse, iReleaseReg);

  return newNotReady;
}

#ifdef WHERETRACE_ENABLED
/*
** Print a WhereLoop object for debugging purposes
*/
static void whereLoopPrint(WhereLoop *p, SrcList *pTabList){
................................................................................
  return SQLITE_OK;
}

/*
** Transfer content from the second pLoop into the first.
*/
static int whereLoopXfer(sqlite3 *db, WhereLoop *pTo, WhereLoop *pFrom){
  if( whereLoopResize(db, pTo, pFrom->nLTerm) ) return SQLITE_NOMEM;
  whereLoopClearUnion(db, pTo);




  memcpy(pTo, pFrom, WHERE_LOOP_XFER_SZ);
  memcpy(pTo->aLTerm, pFrom->aLTerm, pTo->nLTerm*sizeof(pTo->aLTerm[0]));
  if( pFrom->wsFlags & WHERE_VIRTUALTABLE ){
    pFrom->u.vtab.needFree = 0;
  }else if( (pFrom->wsFlags & WHERE_AUTO_INDEX)!=0 ){
    pFrom->u.btree.pIndex = 0;
  }
................................................................................
    ** case first.  Hence compatible candidate WhereLoops never have a larger
    ** rSetup. Call this SETUP-INVARIANT */
    assert( p->rSetup>=pTemplate->rSetup );

    if( (p->prereq & pTemplate->prereq)==p->prereq
     && p->rSetup<=pTemplate->rSetup
     && p->rRun<=pTemplate->rRun

    ){
      /* This branch taken when p is equal or better than pTemplate in 
      ** all of (1) dependences (2) setup-cost, and (3) run-cost. */

      assert( p->rSetup==pTemplate->rSetup );

      if( p->nLTerm<pTemplate->nLTerm
       && (p->wsFlags & WHERE_INDEXED)!=0
       && (pTemplate->wsFlags & WHERE_INDEXED)!=0
       && p->u.btree.pIndex==pTemplate->u.btree.pIndex
       && p->prereq==pTemplate->prereq

      ){
        /* Overwrite an existing WhereLoop with an similar one that uses
        ** more terms of the index */
        pNext = p->pNextLoop;
        break;
      }else{
        /* pTemplate is not helpful.
        ** Return without changing or adding anything */
        goto whereLoopInsert_noop;
      }
    }
    if( (p->prereq & pTemplate->prereq)==pTemplate->prereq
     && p->rRun>=pTemplate->rRun
     && ALWAYS(p->rSetup>=pTemplate->rSetup) /* See SETUP-INVARIANT above */
    ){
      /* Overwrite an existing WhereLoop with a better one: one that is
      ** better at one of (1) dependences, (2) setup-cost, or (3) run-cost
      ** and is no worse in any of those categories. */


      pNext = p->pNextLoop;
      break;
    }
  }

  /* If we reach this point it means that either p[] should be overwritten
  ** with pTemplate[] if p[] exists, or if p==NULL then allocate a new
................................................................................
  if( sqlite3WhereTrace & 0x8 ){
    sqlite3DebugPrintf("ins-noop: ");
    whereLoopPrint(pTemplate, pWInfo->pTabList);
  }
#endif
  return SQLITE_OK;  
}































/*
** We have so far matched pBuilder->pNew->u.btree.nEq terms of the index pIndex.
** Try to match one more.
**
** If pProbe->tnum==0, that means pIndex is a fake index used for the
** INTEGER PRIMARY KEY.
*/
static int whereLoopAddBtreeIndex(
  WhereLoopBuilder *pBuilder,     /* The WhereLoop factory */
  struct SrcList_item *pSrc,      /* FROM clause term being analyzed */
  Index *pProbe,                  /* An index on pSrc */
  WhereCost nInMul                /* log(Number of iterations due to IN) */
){
  WhereInfo *pWInfo = pBuilder->pWInfo;  /* WHERE analyse context */
  Parse *pParse = pWInfo->pParse;        /* Parsing context */
  sqlite3 *db = pParse->db;       /* Database connection malloc context */
  WhereLoop *pNew;                /* Template WhereLoop under construction */
  WhereTerm *pTerm;               /* A WhereTerm under consideration */
  int opMask;                     /* Valid operators for constraints */
  WhereScan scan;                 /* Iterator for WHERE terms */
  Bitmask saved_prereq;           /* Original value of pNew->prereq */
  u16 saved_nLTerm;               /* Original value of pNew->nLTerm */
  int saved_nEq;                  /* Original value of pNew->u.btree.nEq */
  u32 saved_wsFlags;              /* Original value of pNew->wsFlags */
  WhereCost saved_nOut;           /* Original value of pNew->nOut */
  int iCol;                       /* Index of the column in the table */
  int rc = SQLITE_OK;             /* Return code */
  WhereCost nRowEst;              /* Estimated index selectivity */
  WhereCost rLogSize;             /* Logarithm of table size */
  WhereTerm *pTop = 0, *pBtm = 0; /* Top and bottom range constraints */

  pNew = pBuilder->pNew;
  if( db->mallocFailed ) return SQLITE_NOMEM;

  assert( (pNew->wsFlags & WHERE_VIRTUALTABLE)==0 );
  assert( (pNew->wsFlags & WHERE_TOP_LIMIT)==0 );
................................................................................
    opMask = WO_EQ|WO_IN|WO_ISNULL|WO_GT|WO_GE|WO_LT|WO_LE;
  }
  if( pProbe->bUnordered ) opMask &= ~(WO_GT|WO_GE|WO_LT|WO_LE);

  assert( pNew->u.btree.nEq<=pProbe->nColumn );
  if( pNew->u.btree.nEq < pProbe->nColumn ){
    iCol = pProbe->aiColumn[pNew->u.btree.nEq];
    nRowEst = whereCost(pProbe->aiRowEst[pNew->u.btree.nEq+1]);
    if( nRowEst==0 && pProbe->onError==OE_None ) nRowEst = 1;
  }else{
    iCol = -1;
    nRowEst = 0;
  }
  pTerm = whereScanInit(&scan, pBuilder->pWC, pSrc->iCursor, iCol,
                        opMask, pProbe);
  saved_nEq = pNew->u.btree.nEq;
  saved_nLTerm = pNew->nLTerm;
  saved_wsFlags = pNew->wsFlags;
  saved_prereq = pNew->prereq;
  saved_nOut = pNew->nOut;
  pNew->rSetup = 0;
  rLogSize = estLog(whereCost(pProbe->aiRowEst[0]));
  for(; rc==SQLITE_OK && pTerm!=0; pTerm = whereScanNext(&scan)){
    int nIn = 0;
    if( pTerm->prereqRight & pNew->maskSelf ) continue;


    if( (pTerm->eOperator==WO_ISNULL || (pTerm->wtFlags&TERM_VNULL)!=0)
     && (iCol<0 || pSrc->pTab->aCol[iCol].notNull)
    ){
      continue; /* ignore IS [NOT] NULL constraints on NOT NULL columns */
    }




    pNew->wsFlags = saved_wsFlags;
    pNew->u.btree.nEq = saved_nEq;
    pNew->nLTerm = saved_nLTerm;
    if( whereLoopResize(db, pNew, pNew->nLTerm+1) ) break; /* OOM */
    pNew->aLTerm[pNew->nLTerm++] = pTerm;
    pNew->prereq = (saved_prereq | pTerm->prereqRight) & ~pNew->maskSelf;
    pNew->rRun = rLogSize; /* Baseline cost is log2(N).  Adjustments below */
    if( pTerm->eOperator & WO_IN ){
      Expr *pExpr = pTerm->pExpr;
      pNew->wsFlags |= WHERE_COLUMN_IN;
      if( ExprHasProperty(pExpr, EP_xIsSelect) ){
        /* "x IN (SELECT ...)":  TUNING: the SELECT returns 25 rows */
        nIn = 46;  assert( 46==whereCost(25) );
      }else if( ALWAYS(pExpr->x.pList && pExpr->x.pList->nExpr) ){
        /* "x IN (value, value, ...)" */
        nIn = whereCost(pExpr->x.pList->nExpr);
      }
      pNew->rRun += nIn;
      pNew->u.btree.nEq++;
      pNew->nOut = nRowEst + nInMul + nIn;
    }else if( pTerm->eOperator & (WO_EQ) ){
      assert( (pNew->wsFlags & (WHERE_COLUMN_NULL|WHERE_COLUMN_IN))!=0
                  || nInMul==0 );
................................................................................
      }
      pNew->u.btree.nEq++;
      pNew->nOut = nRowEst + nInMul;
    }else if( pTerm->eOperator & (WO_ISNULL) ){
      pNew->wsFlags |= WHERE_COLUMN_NULL;
      pNew->u.btree.nEq++;
      /* TUNING: IS NULL selects 2 rows */
      nIn = 10;  assert( 10==whereCost(2) );
      pNew->nOut = nRowEst + nInMul + nIn;
    }else if( pTerm->eOperator & (WO_GT|WO_GE) ){
      testcase( pTerm->eOperator & WO_GT );
      testcase( pTerm->eOperator & WO_GE );
      pNew->wsFlags |= WHERE_COLUMN_RANGE|WHERE_BTM_LIMIT;
      pBtm = pTerm;
      pTop = 0;
................................................................................
      pNew->wsFlags |= WHERE_COLUMN_RANGE|WHERE_TOP_LIMIT;
      pTop = pTerm;
      pBtm = (pNew->wsFlags & WHERE_BTM_LIMIT)!=0 ?
                     pNew->aLTerm[pNew->nLTerm-2] : 0;
    }
    if( pNew->wsFlags & WHERE_COLUMN_RANGE ){
      /* Adjust nOut and rRun for STAT3 range values */
      WhereCost rDiv;
      whereRangeScanEst(pParse, pProbe, pNew->u.btree.nEq,
                        pBtm, pTop, &rDiv);
      pNew->nOut = saved_nOut>rDiv+10 ? saved_nOut - rDiv : 10;
    }
#ifdef SQLITE_ENABLE_STAT3

    if( pNew->u.btree.nEq==1 && pProbe->nSample

     &&  OptimizationEnabled(db, SQLITE_Stat3) ){


      tRowcnt nOut = 0;
      if( (pTerm->eOperator & (WO_EQ|WO_ISNULL))!=0 ){
        testcase( pTerm->eOperator & WO_EQ );
        testcase( pTerm->eOperator & WO_ISNULL );
        rc = whereEqualScanEst(pParse, pProbe, pTerm->pExpr->pRight, &nOut);
      }else if( (pTerm->eOperator & WO_IN)
             &&  !ExprHasProperty(pTerm->pExpr, EP_xIsSelect)  ){
        rc = whereInScanEst(pParse, pProbe, pTerm->pExpr->x.pList, &nOut);
      }
      assert( nOut==0 || rc==SQLITE_OK );


      if( nOut ) pNew->nOut = whereCost(nOut);

    }
#endif
    if( (pNew->wsFlags & (WHERE_IDX_ONLY|WHERE_IPK))==0 ){
      /* Each row involves a step of the index, then a binary search of
      ** the main table */
      pNew->rRun =  whereCostAdd(pNew->rRun, rLogSize>27 ? rLogSize-17 : 10);
    }
    /* Step cost for each output row */
    pNew->rRun = whereCostAdd(pNew->rRun, pNew->nOut);
    /* TBD: Adjust nOut for additional constraints */
    rc = whereLoopInsert(pBuilder, pNew);
    if( (pNew->wsFlags & WHERE_TOP_LIMIT)==0
     && pNew->u.btree.nEq<(pProbe->nColumn + (pProbe->zName!=0))
    ){
      whereLoopAddBtreeIndex(pBuilder, pSrc, pProbe, nInMul+nIn);
    }




  }
  pNew->prereq = saved_prereq;
  pNew->u.btree.nEq = saved_nEq;
  pNew->wsFlags = saved_wsFlags;
  pNew->nOut = saved_nOut;
  pNew->nLTerm = saved_nLTerm;
  return rc;
................................................................................
  int aiColumnPk = -1;        /* The aColumn[] value for the sPk index */
  SrcList *pTabList;          /* The FROM clause */
  struct SrcList_item *pSrc;  /* The FROM clause btree term to add */
  WhereLoop *pNew;            /* Template WhereLoop object */
  int rc = SQLITE_OK;         /* Return code */
  int iSortIdx = 1;           /* Index number */
  int b;                      /* A boolean value */
  WhereCost rSize;            /* number of rows in the table */
  WhereCost rLogSize;         /* Logarithm of the number of rows in the table */
  WhereClause *pWC;           /* The parsed WHERE clause */

  
  pNew = pBuilder->pNew;
  pWInfo = pBuilder->pWInfo;
  pTabList = pWInfo->pTabList;
  pSrc = pTabList->a + pNew->iTab;

  pWC = pBuilder->pWC;
  assert( !IsVirtual(pSrc->pTab) );

  if( pSrc->pIndex ){
    /* An INDEXED BY clause specifies a particular index to use */
    pProbe = pSrc->pIndex;
  }else{
................................................................................
    ** indices to follow */
    Index *pFirst;                  /* First of real indices on the table */
    memset(&sPk, 0, sizeof(Index));
    sPk.nColumn = 1;
    sPk.aiColumn = &aiColumnPk;
    sPk.aiRowEst = aiRowEstPk;
    sPk.onError = OE_Replace;
    sPk.pTable = pSrc->pTab;
    aiRowEstPk[0] = pSrc->pTab->nRowEst;
    aiRowEstPk[1] = 1;
    pFirst = pSrc->pTab->pIndex;
    if( pSrc->notIndexed==0 ){
      /* The real indices of the table are only considered if the
      ** NOT INDEXED qualifier is omitted from the FROM clause */
      sPk.pNext = pFirst;
    }
    pProbe = &sPk;
  }
  rSize = whereCost(pSrc->pTab->nRowEst);
  rLogSize = estLog(rSize);


  /* Automatic indexes */
  if( !pBuilder->pOrSet
   && (pWInfo->pParse->db->flags & SQLITE_AutoIndex)!=0
   && pSrc->pIndex==0
   && !pSrc->viaCoroutine
   && !pSrc->notIndexed
   && !pSrc->isCorrelated
................................................................................
        pNew->u.btree.nEq = 1;
        pNew->u.btree.pIndex = 0;
        pNew->nLTerm = 1;
        pNew->aLTerm[0] = pTerm;
        /* TUNING: One-time cost for computing the automatic index is
        ** approximately 7*N*log2(N) where N is the number of rows in
        ** the table being indexed. */
        pNew->rSetup = rLogSize + rSize + 28;  assert( 28==whereCost(7) );
        /* TUNING: Each index lookup yields 20 rows in the table.  This
        ** is more than the usual guess of 10 rows, since we have no way
        ** of knowning how selective the index will ultimately be.  It would
        ** not be unreasonable to make this value much larger. */
        pNew->nOut = 43;  assert( 43==whereCost(20) );
        pNew->rRun = whereCostAdd(rLogSize,pNew->nOut);
        pNew->wsFlags = WHERE_AUTO_INDEX;
        pNew->prereq = mExtra | pTerm->prereqRight;
        rc = whereLoopInsert(pBuilder, pNew);
      }
    }
  }


  /* Loop over all indices
  */
  for(; rc==SQLITE_OK && pProbe; pProbe=pProbe->pNext, iSortIdx++){
    if( pProbe->pPartIdxWhere!=0
     && !whereUsablePartialIndex(pNew->iTab, pWC, pProbe->pPartIdxWhere) ){
      continue;  /* Partial index inappropriate for this query */
................................................................................
      /* Integer primary key index */
      pNew->wsFlags = WHERE_IPK;

      /* Full table scan */
      pNew->iSortIdx = b ? iSortIdx : 0;
      /* TUNING: Cost of full table scan is 3*(N + log2(N)).
      **  +  The extra 3 factor is to encourage the use of indexed lookups
      **     over full scans.  A smaller constant 2 is used for covering
      **     index scans so that a covering index scan will be favored over
      **     a table scan. */
      pNew->rRun = whereCostAdd(rSize,rLogSize) + 16;
      rc = whereLoopInsert(pBuilder, pNew);
      if( rc ) break;
    }else{
      Bitmask m = pSrc->colUsed & ~columnsInIndex(pProbe);
      pNew->wsFlags = (m==0) ? (WHERE_IDX_ONLY|WHERE_INDEXED) : WHERE_INDEXED;

      /* Full scan via index */
      if( b
       || ( m==0
         && pProbe->bUnordered==0

         && (pWInfo->wctrlFlags & WHERE_ONEPASS_DESIRED)==0
         && sqlite3GlobalConfig.bUseCis
         && OptimizationEnabled(pWInfo->pParse->db, SQLITE_CoverIdxScan)
          )
      ){
        pNew->iSortIdx = b ? iSortIdx : 0;
        if( m==0 ){
          /* TUNING: Cost of a covering index scan is 2*(N + log2(N)).
          **  +  The extra 2 factor is to encourage the use of indexed lookups
          **     over index scans.  A table scan uses a factor of 3 so that
          **     index scans are favored over table scans.
          **  +  If this covering index might also help satisfy the ORDER BY
          **     clause, then the cost is fudged down slightly so that this
          **     index is favored above other indices that have no hope of
          **     helping with the ORDER BY. */
          pNew->rRun = 10 + whereCostAdd(rSize,rLogSize) - b;

        }else{
          assert( b!=0 ); 
          /* TUNING: Cost of scanning a non-covering index is (N+1)*log2(N)
          ** which we will simplify to just N*log2(N) */
          pNew->rRun = rSize + rLogSize;
        }

        rc = whereLoopInsert(pBuilder, pNew);

        if( rc ) break;
      }
    }

    rc = whereLoopAddBtreeIndex(pBuilder, pSrc, pProbe, 0);






    /* If there was an INDEXED BY clause, then only that one index is
    ** considered. */
    if( pSrc->pIndex ) break;
  }
  return rc;
}
................................................................................
      pNew->u.vtab.idxNum = pIdxInfo->idxNum;
      pNew->u.vtab.needFree = pIdxInfo->needToFreeIdxStr;
      pIdxInfo->needToFreeIdxStr = 0;
      pNew->u.vtab.idxStr = pIdxInfo->idxStr;
      pNew->u.vtab.isOrdered = (u8)((pIdxInfo->nOrderBy!=0)
                                     && pIdxInfo->orderByConsumed);
      pNew->rSetup = 0;
      pNew->rRun = whereCostFromDouble(pIdxInfo->estimatedCost);
      /* TUNING: Every virtual table query returns 25 rows */
      pNew->nOut = 46;  assert( 46==whereCost(25) );
      whereLoopInsert(pBuilder, pNew);
      if( pNew->u.vtab.needFree ){
        sqlite3_free(pNew->u.vtab.idxStr);
        pNew->u.vtab.needFree = 0;
      }
    }
  }  
................................................................................
  struct SrcList_item *pItem;
  
  pWC = pBuilder->pWC;
  if( pWInfo->wctrlFlags & WHERE_AND_ONLY ) return SQLITE_OK;
  pWCEnd = pWC->a + pWC->nTerm;
  pNew = pBuilder->pNew;
  memset(&sSum, 0, sizeof(sSum));



  for(pTerm=pWC->a; pTerm<pWCEnd && rc==SQLITE_OK; pTerm++){
    if( (pTerm->eOperator & WO_OR)!=0
     && (pTerm->u.pOrInfo->indexable & pNew->maskSelf)!=0 
    ){
      WhereClause * const pOrWC = &pTerm->u.pOrInfo->wc;
      WhereTerm * const pOrWCEnd = &pOrWC->a[pOrWC->nTerm];
      WhereTerm *pOrTerm;
      int once = 1;
      int i, j;
    
      pItem = pWInfo->pTabList->a + pNew->iTab;
      iCur = pItem->iCursor;
      sSubBuild = *pBuilder;
      sSubBuild.pOrderBy = 0;
      sSubBuild.pOrSet = &sCur;

      for(pOrTerm=pOrWC->a; pOrTerm<pOrWCEnd; pOrTerm++){
        if( (pOrTerm->eOperator & WO_AND)!=0 ){
          sSubBuild.pWC = &pOrTerm->u.pAndInfo->wc;
................................................................................
          once = 0;
        }else{
          whereOrMove(&sPrev, &sSum);
          sSum.n = 0;
          for(i=0; i<sPrev.n; i++){
            for(j=0; j<sCur.n; j++){
              whereOrInsert(&sSum, sPrev.a[i].prereq | sCur.a[j].prereq,
                            whereCostAdd(sPrev.a[i].rRun, sCur.a[j].rRun),
                            whereCostAdd(sPrev.a[i].nOut, sCur.a[j].nOut));
            }
          }
        }
      }
      pNew->nLTerm = 1;
      pNew->aLTerm[0] = pTerm;
      pNew->wsFlags = WHERE_MULTI_OR;
................................................................................
** Assume that the total number of output rows that will need to be sorted
** will be nRowEst (in the 10*log2 representation).  Or, ignore sorting
** costs if nRowEst==0.
**
** Return SQLITE_OK on success or SQLITE_NOMEM of a memory allocation
** error occurs.
*/
static int wherePathSolver(WhereInfo *pWInfo, WhereCost nRowEst){
  int mxChoice;             /* Maximum number of simultaneous paths tracked */
  int nLoop;                /* Number of terms in the join */
  Parse *pParse;            /* Parsing context */
  sqlite3 *db;              /* The database connection */
  int iLoop;                /* Loop counter over the terms of the join */
  int ii, jj;               /* Loop counters */

  WhereCost rCost;             /* Cost of a path */

  WhereCost mxCost = 0;        /* Maximum cost of a set of paths */

  WhereCost rSortCost;         /* Cost to do a sort */
  int nTo, nFrom;           /* Number of valid entries in aTo[] and aFrom[] */
  WherePath *aFrom;         /* All nFrom paths at the previous level */
  WherePath *aTo;           /* The nTo best paths at the current level */
  WherePath *pFrom;         /* An element of aFrom[] that we are working on */
  WherePath *pTo;           /* An element of aTo[] that we are working on */
  WhereLoop *pWLoop;        /* One of the WhereLoop objects */
  WhereLoop **pX;           /* Used to divy up the pSpace memory */
................................................................................
  }

  /* Seed the search with a single WherePath containing zero WhereLoops.
  **
  ** TUNING: Do not let the number of iterations go above 25.  If the cost
  ** of computing an automatic index is not paid back within the first 25
  ** rows, then do not use the automatic index. */
  aFrom[0].nRow = MIN(pParse->nQueryLoop, 46);  assert( 46==whereCost(25) );
  nFrom = 1;

  /* Precompute the cost of sorting the final result set, if the caller
  ** to sqlite3WhereBegin() was concerned about sorting */
  rSortCost = 0;
  if( pWInfo->pOrderBy==0 || nRowEst==0 ){
    aFrom[0].isOrderedValid = 1;
  }else{
    /* TUNING: Estimated cost of sorting is N*log2(N) where N is the
    ** number of output rows. */


    rSortCost = nRowEst + estLog(nRowEst);
    WHERETRACE(0x002,("---- sort cost=%-3d\n", rSortCost));
  }

  /* Compute successively longer WherePaths using the previous generation
  ** of WherePaths as the basis for the next.  Keep track of the mxChoice
  ** best paths at each generation */
................................................................................
        Bitmask revMask = 0;
        u8 isOrderedValid = pFrom->isOrderedValid;
        u8 isOrdered = pFrom->isOrdered;
        if( (pWLoop->prereq & ~pFrom->maskLoop)!=0 ) continue;
        if( (pWLoop->maskSelf & pFrom->maskLoop)!=0 ) continue;
        /* At this point, pWLoop is a candidate to be the next loop. 
        ** Compute its cost */
        rCost = whereCostAdd(pWLoop->rSetup,pWLoop->rRun + pFrom->nRow);
        rCost = whereCostAdd(rCost, pFrom->rCost);

        maskNew = pFrom->maskLoop | pWLoop->maskSelf;
        if( !isOrderedValid ){
          switch( wherePathSatisfiesOrderBy(pWInfo,
                       pWInfo->pOrderBy, pFrom, pWInfo->wctrlFlags,
                       iLoop, pWLoop, &revMask) ){
            case 1:  /* Yes.  pFrom+pWLoop does satisfy the ORDER BY clause */
              isOrdered = 1;
              isOrderedValid = 1;
              break;
            case 0:  /* No.  pFrom+pWLoop will require a separate sort */
              isOrdered = 0;
              isOrderedValid = 1;
              rCost = whereCostAdd(rCost, rSortCost);
              break;
            default: /* Cannot tell yet.  Try again on the next iteration */
              break;
          }
        }else{
          revMask = pFrom->revLoop;
        }
        /* Check to see if pWLoop should be added to the mxChoice best so far */
        for(jj=0, pTo=aTo; jj<nTo; jj++, pTo++){

          if( pTo->maskLoop==maskNew && pTo->isOrderedValid==isOrderedValid ){



            testcase( jj==nTo-1 );
            break;
          }
        }
        if( jj>=nTo ){
          if( nTo>=mxChoice && rCost>=mxCost ){
#ifdef WHERETRACE_ENABLED
            if( sqlite3WhereTrace&0x4 ){
              sqlite3DebugPrintf("Skip   %s cost=%3d order=%c\n",
                  wherePathName(pFrom, iLoop, pWLoop), rCost,
                  isOrderedValid ? (isOrdered ? 'Y' : 'N') : '?');
            }
#endif
            continue;
          }
          /* Add a new Path to the aTo[] set */
          if( nTo<mxChoice ){
            /* Increase the size of the aTo set by one */
            jj = nTo++;
          }else{
            /* New path replaces the prior worst to keep count below mxChoice */
            for(jj=nTo-1; aTo[jj].rCost<mxCost; jj--){ assert(jj>0); }
          }
          pTo = &aTo[jj];
#ifdef WHERETRACE_ENABLED
          if( sqlite3WhereTrace&0x4 ){
            sqlite3DebugPrintf("New    %s cost=%-3d order=%c\n",
                wherePathName(pFrom, iLoop, pWLoop), rCost,
                isOrderedValid ? (isOrdered ? 'Y' : 'N') : '?');
          }
#endif
        }else{
          if( pTo->rCost<=rCost ){
#ifdef WHERETRACE_ENABLED
            if( sqlite3WhereTrace&0x4 ){
              sqlite3DebugPrintf(
                  "Skip   %s cost=%-3d order=%c",
                  wherePathName(pFrom, iLoop, pWLoop), rCost,
                  isOrderedValid ? (isOrdered ? 'Y' : 'N') : '?');
              sqlite3DebugPrintf("   vs %s cost=%-3d order=%c\n",
                  wherePathName(pTo, iLoop+1, 0), pTo->rCost,
                  pTo->isOrderedValid ? (pTo->isOrdered ? 'Y' : 'N') : '?');
            }
#endif
            testcase( pTo->rCost==rCost );
            continue;
          }
          testcase( pTo->rCost==rCost+1 );
          /* A new and better score for a previously created equivalent path */
#ifdef WHERETRACE_ENABLED
          if( sqlite3WhereTrace&0x4 ){
            sqlite3DebugPrintf(
                "Update %s cost=%-3d order=%c",
                wherePathName(pFrom, iLoop, pWLoop), rCost,
                isOrderedValid ? (isOrdered ? 'Y' : 'N') : '?');
            sqlite3DebugPrintf("  was %s cost=%-3d order=%c\n",
                wherePathName(pTo, iLoop+1, 0), pTo->rCost,
                pTo->isOrderedValid ? (pTo->isOrdered ? 'Y' : 'N') : '?');
          }
#endif
        }
        /* pWLoop is a winner.  Add it to the set of best so far */
        pTo->maskLoop = pFrom->maskLoop | pWLoop->maskSelf;
        pTo->revLoop = revMask;
        pTo->nRow = pFrom->nRow + pWLoop->nOut;
        pTo->rCost = rCost;
        pTo->isOrderedValid = isOrderedValid;
        pTo->isOrdered = isOrdered;
        memcpy(pTo->aLoop, pFrom->aLoop, sizeof(WhereLoop*)*iLoop);
        pTo->aLoop[iLoop] = pWLoop;
        if( nTo>=mxChoice ){

          mxCost = aTo[0].rCost;

          for(jj=1, pTo=&aTo[1]; jj<mxChoice; jj++, pTo++){

            if( pTo->rCost>mxCost ) mxCost = pTo->rCost;



          }
        }
      }
    }

#ifdef WHERETRACE_ENABLED
    if( sqlite3WhereTrace>=2 ){
................................................................................
    sqlite3ErrorMsg(pParse, "no query solution");
    sqlite3DbFree(db, pSpace);
    return SQLITE_ERROR;
  }
  
  /* Find the lowest cost path.  pFrom will be left pointing to that path */
  pFrom = aFrom;
  assert( nFrom==1 );
#if 0 /* The following is needed if nFrom is ever more than 1 */
  for(ii=1; ii<nFrom; ii++){
    if( pFrom->rCost>aFrom[ii].rCost ) pFrom = &aFrom[ii];
  }
#endif
  assert( pWInfo->nLevel==nLoop );
  /* Load the lowest cost path into pWInfo */
  for(iLoop=0; iLoop<nLoop; iLoop++){
    WhereLevel *pLevel = pWInfo->a + iLoop;
    pLevel->pWLoop = pWLoop = pFrom->aLoop[iLoop];
    pLevel->iFrom = pWLoop->iTab;
    pLevel->iTabCur = pWInfo->pTabList->a[pLevel->iFrom].iCursor;
................................................................................
  pTerm = findTerm(pWC, iCur, -1, 0, WO_EQ, 0);
  if( pTerm ){
    pLoop->wsFlags = WHERE_COLUMN_EQ|WHERE_IPK|WHERE_ONEROW;
    pLoop->aLTerm[0] = pTerm;
    pLoop->nLTerm = 1;
    pLoop->u.btree.nEq = 1;
    /* TUNING: Cost of a rowid lookup is 10 */
    pLoop->rRun = 33;  /* 33==whereCost(10) */
  }else{
    for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){


      if( pIdx->onError==OE_None || pIdx->pPartIdxWhere!=0 ) continue;



      for(j=0; j<pIdx->nColumn; j++){
        pTerm = findTerm(pWC, iCur, pIdx->aiColumn[j], 0, WO_EQ, pIdx);
        if( pTerm==0 ) break;
        whereLoopResize(pWInfo->pParse->db, pLoop, j);
        pLoop->aLTerm[j] = pTerm;
      }
      if( j!=pIdx->nColumn ) continue;
      pLoop->wsFlags = WHERE_COLUMN_EQ|WHERE_ONEROW|WHERE_INDEXED;
      if( (pItem->colUsed & ~columnsInIndex(pIdx))==0 ){
        pLoop->wsFlags |= WHERE_IDX_ONLY;
      }
      pLoop->nLTerm = j;
      pLoop->u.btree.nEq = j;
      pLoop->u.btree.pIndex = pIdx;
      /* TUNING: Cost of a unique index lookup is 15 */
      pLoop->rRun = 39;  /* 39==whereCost(15) */
      break;
    }
  }
  if( pLoop->wsFlags ){
    pLoop->nOut = (WhereCost)1;
    pWInfo->a[0].pWLoop = pLoop;
    pLoop->maskSelf = getMask(&pWInfo->sMaskSet, iCur);
    pWInfo->a[0].iTabCur = iCur;
    pWInfo->nRowOut = 1;
    if( pWInfo->pOrderBy ) pWInfo->bOBSat =  1;
    if( pWInfo->wctrlFlags & WHERE_WANT_DISTINCT ){
      pWInfo->eDistinct = WHERE_DISTINCT_UNIQUE;
................................................................................
#endif
  /* Attempt to omit tables from the join that do not effect the result */
  if( pWInfo->nLevel>=2
   && pResultSet!=0
   && OptimizationEnabled(db, SQLITE_OmitNoopJoin)
  ){
    Bitmask tabUsed = exprListTableUsage(pMaskSet, pResultSet);
    if( pOrderBy ) tabUsed |= exprListTableUsage(pMaskSet, pOrderBy);
    while( pWInfo->nLevel>=2 ){
      WhereTerm *pTerm, *pEnd;
      pLoop = pWInfo->a[pWInfo->nLevel-1].pWLoop;
      if( (pWInfo->pTabList->a[pLoop->iTab].jointype & JT_LEFT)==0 ) break;
      if( (wctrlFlags & WHERE_WANT_DISTINCT)==0
       && (pLoop->wsFlags & WHERE_ONEROW)==0
      ){
................................................................................
    }
  }
  WHERETRACE(0xffff,("*** Optimizer Finished ***\n"));
  pWInfo->pParse->nQueryLoop += pWInfo->nRowOut;

  /* If the caller is an UPDATE or DELETE statement that is requesting
  ** to use a one-pass algorithm, determine if this is appropriate.
  ** The one-pass algorithm only works if the WHERE clause constraints
  ** the statement to update a single row.
  */
  assert( (wctrlFlags & WHERE_ONEPASS_DESIRED)==0 || pWInfo->nLevel==1 );
  if( (wctrlFlags & WHERE_ONEPASS_DESIRED)!=0 
   && (pWInfo->a[0].pWLoop->wsFlags & WHERE_ONEROW)!=0 ){
    pWInfo->okOnePass = 1;
    pWInfo->a[0].pWLoop->wsFlags &= ~WHERE_IDX_ONLY;
................................................................................
    }
    yygotominor.yy342.zStart = yymsp[-3].minor.yy0.z;
    yygotominor.yy342.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
  }
        break;
      case 231: /* expr ::= CASE case_operand case_exprlist case_else END */
{
  yygotominor.yy342.pExpr = sqlite3PExpr(pParse, TK_CASE, yymsp[-3].minor.yy122, yymsp[-1].minor.yy122, 0);
  if( yygotominor.yy342.pExpr ){
    yygotominor.yy342.pExpr->x.pList = yymsp[-2].minor.yy442;
    sqlite3ExprSetHeight(pParse, yygotominor.yy342.pExpr);
  }else{
    sqlite3ExprListDelete(pParse->db, yymsp[-2].minor.yy442);

  }
  yygotominor.yy342.zStart = yymsp[-4].minor.yy0.z;
  yygotominor.yy342.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
}
        break;
      case 232: /* case_exprlist ::= case_exprlist WHEN expr THEN expr */
{
................................................................................
      case SQLITE_IOERR_SHMSIZE:      zName = "SQLITE_IOERR_SHMSIZE";     break;
      case SQLITE_IOERR_SHMLOCK:      zName = "SQLITE_IOERR_SHMLOCK";     break;
      case SQLITE_IOERR_SHMMAP:       zName = "SQLITE_IOERR_SHMMAP";      break;
      case SQLITE_IOERR_SEEK:         zName = "SQLITE_IOERR_SEEK";        break;
      case SQLITE_IOERR_DELETE_NOENT: zName = "SQLITE_IOERR_DELETE_NOENT";break;
      case SQLITE_IOERR_MMAP:         zName = "SQLITE_IOERR_MMAP";        break;
      case SQLITE_IOERR_GETTEMPPATH:  zName = "SQLITE_IOERR_GETTEMPPATH"; break;

      case SQLITE_CORRUPT:            zName = "SQLITE_CORRUPT";           break;
      case SQLITE_CORRUPT_VTAB:       zName = "SQLITE_CORRUPT_VTAB";      break;
      case SQLITE_NOTFOUND:           zName = "SQLITE_NOTFOUND";          break;
      case SQLITE_FULL:               zName = "SQLITE_FULL";              break;
      case SQLITE_CANTOPEN:           zName = "SQLITE_CANTOPEN";          break;
      case SQLITE_CANTOPEN_NOTEMPDIR: zName = "SQLITE_CANTOPEN_NOTEMPDIR";break;
      case SQLITE_CANTOPEN_ISDIR:     zName = "SQLITE_CANTOPEN_ISDIR";    break;
      case SQLITE_CANTOPEN_FULLPATH:  zName = "SQLITE_CANTOPEN_FULLPATH"; break;

      case SQLITE_PROTOCOL:           zName = "SQLITE_PROTOCOL";          break;
      case SQLITE_EMPTY:              zName = "SQLITE_EMPTY";             break;
      case SQLITE_SCHEMA:             zName = "SQLITE_SCHEMA";            break;
      case SQLITE_TOOBIG:             zName = "SQLITE_TOOBIG";            break;
      case SQLITE_CONSTRAINT:         zName = "SQLITE_CONSTRAINT";        break;
      case SQLITE_CONSTRAINT_UNIQUE:  zName = "SQLITE_CONSTRAINT_UNIQUE"; break;
      case SQLITE_CONSTRAINT_TRIGGER: zName = "SQLITE_CONSTRAINT_TRIGGER";break;
................................................................................
  
  /* Check if an existing function is being overridden or deleted. If so,
  ** and there are active VMs, then return SQLITE_BUSY. If a function
  ** is being overridden/deleted but there are no active VMs, allow the
  ** operation to continue but invalidate all precompiled statements.
  */
  p = sqlite3FindFunction(db, zFunctionName, nName, nArg, (u8)enc, 0);
  if( p && p->iPrefEnc==enc && p->nArg==nArg ){
    if( db->nVdbeActive ){
      sqlite3Error(db, SQLITE_BUSY, 
        "unable to delete/modify user-function due to active statements");
      assert( !db->mallocFailed );
      return SQLITE_BUSY;
    }else{
      sqlite3ExpirePreparedStatements(db);
................................................................................
  ** being replaced invoke the destructor function here. */
  functionDestroy(db, p);

  if( pDestructor ){
    pDestructor->nRef++;
  }
  p->pDestructor = pDestructor;
  p->flags = 0;
  p->xFunc = xFunc;
  p->xStep = xStep;
  p->xFinalize = xFinal;
  p->pUserData = pUserData;
  p->nArg = (u16)nArg;
  return SQLITE_OK;
}
................................................................................
  ** methods of the virtual table are called at appropriate times.  These
  ** values do not contribute to FTS functionality; they are used for
  ** verifying the operation of the SQLite core.
  */
  int inTransaction;     /* True after xBegin but before xCommit/xRollback */
  int mxSavepoint;       /* Largest valid xSavepoint integer */
#endif






};

/*
** When the core wants to read from the virtual table, it creates a
** virtual table cursor (an instance of the following structure) using
** the xOpen method. Cursors are destroyed using the xClose method.
*/
................................................................................
  char *pNextId;                  /* Pointer into the body of aDoclist */
  char *aDoclist;                 /* List of docids for full-text queries */
  int nDoclist;                   /* Size of buffer at aDoclist */
  u8 bDesc;                       /* True to sort in descending order */
  int eEvalmode;                  /* An FTS3_EVAL_XX constant */
  int nRowAvg;                    /* Average size of database rows, in pages */
  sqlite3_int64 nDoc;             /* Documents in table */


  int isMatchinfoNeeded;          /* True when aMatchinfo[] needs filling in */
  u32 *aMatchinfo;                /* Information about most recent match */
  int nMatchinfo;                 /* Number of elements in aMatchinfo[] */
  char *zMatchinfo;               /* Matchinfo specification */
};

#define FTS3_EVAL_FILTER    0
................................................................................
** indicating that all columns should be searched,
** then eSearch would be set to FTS3_FULLTEXT_SEARCH+4.
*/
#define FTS3_FULLSCAN_SEARCH 0    /* Linear scan of %_content table */
#define FTS3_DOCID_SEARCH    1    /* Lookup by rowid on %_content table */
#define FTS3_FULLTEXT_SEARCH 2    /* Full-text index search */











struct Fts3Doclist {
  char *aAll;                    /* Array containing doclist (or NULL) */
  int nAll;                      /* Size of a[] in bytes */
  char *pNextDocid;              /* Pointer to next docid */

  sqlite3_int64 iDocid;          /* Current docid (if pList!=0) */
................................................................................
**   2. Full-text search using a MATCH operator on a non-docid column.
**   3. Linear scan of %_content table.
*/
static int fts3BestIndexMethod(sqlite3_vtab *pVTab, sqlite3_index_info *pInfo){
  Fts3Table *p = (Fts3Table *)pVTab;
  int i;                          /* Iterator variable */
  int iCons = -1;                 /* Index of constraint to use */

  int iLangidCons = -1;           /* Index of langid=x constraint, if present */




  /* By default use a full table scan. This is an expensive option,
  ** so search through the constraints to see if a more efficient 
  ** strategy is possible.
  */
  pInfo->idxNum = FTS3_FULLSCAN_SEARCH;
  pInfo->estimatedCost = 5000000;
  for(i=0; i<pInfo->nConstraint; i++){

    struct sqlite3_index_constraint *pCons = &pInfo->aConstraint[i];
    if( pCons->usable==0 ) continue;



    /* A direct lookup on the rowid or docid column. Assign a cost of 1.0. */
    if( iCons<0 
     && pCons->op==SQLITE_INDEX_CONSTRAINT_EQ 
     && (pCons->iColumn<0 || pCons->iColumn==p->nColumn+1 )
    ){
      pInfo->idxNum = FTS3_DOCID_SEARCH;
      pInfo->estimatedCost = 1.0;
      iCons = i;
    }

    /* A MATCH constraint. Use a full-text search.
    **
................................................................................

    /* Equality constraint on the langid column */
    if( pCons->op==SQLITE_INDEX_CONSTRAINT_EQ 
     && pCons->iColumn==p->nColumn + 2
    ){
      iLangidCons = i;
    }
  }
















  if( iCons>=0 ){
    pInfo->aConstraintUsage[iCons].argvIndex = 1;
    pInfo->aConstraintUsage[iCons].omit = 1;
  } 
  if( iLangidCons>=0 ){

    pInfo->aConstraintUsage[iLangidCons].argvIndex = 2;








  } 

  /* Regardless of the strategy selected, FTS can deliver rows in rowid (or
  ** docid) order. Both ascending and descending are possible. 
  */
  if( pInfo->nOrderBy==1 ){
    struct sqlite3_index_orderby *pOrder = &pInfo->aOrderBy[0];
................................................................................
    }
  }else{
    rc = fts3EvalNext((Fts3Cursor *)pCursor);
  }
  assert( ((Fts3Table *)pCsr->base.pVtab)->pSegments==0 );
  return rc;
}




























/*
** This is the xFilter interface for the virtual table.  See
** the virtual table xFilter method documentation for additional
** information.
**
** If idxNum==FTS3_FULLSCAN_SEARCH then do a full table scan against
................................................................................
  int idxNum,                     /* Strategy index */
  const char *idxStr,             /* Unused */
  int nVal,                       /* Number of elements in apVal */
  sqlite3_value **apVal           /* Arguments for the indexing scheme */
){
  int rc;
  char *zSql;                     /* SQL statement used to access %_content */

  Fts3Table *p = (Fts3Table *)pCursor->pVtab;
  Fts3Cursor *pCsr = (Fts3Cursor *)pCursor;







  UNUSED_PARAMETER(idxStr);
  UNUSED_PARAMETER(nVal);


  assert( idxNum>=0 && idxNum<=(FTS3_FULLTEXT_SEARCH+p->nColumn) );
  assert( nVal==0 || nVal==1 || nVal==2 );
  assert( (nVal==0)==(idxNum==FTS3_FULLSCAN_SEARCH) );
  assert( p->pSegments==0 );









  /* In case the cursor has been used before, clear it now. */
  sqlite3_finalize(pCsr->pStmt);
  sqlite3_free(pCsr->aDoclist);
  sqlite3Fts3ExprFree(pCsr->pExpr);
  memset(&pCursor[1], 0, sizeof(Fts3Cursor)-sizeof(sqlite3_vtab_cursor));





  if( idxStr ){
    pCsr->bDesc = (idxStr[0]=='D');
  }else{
    pCsr->bDesc = p->bDescIdx;
  }
  pCsr->eSearch = (i16)idxNum;

  if( idxNum!=FTS3_DOCID_SEARCH && idxNum!=FTS3_FULLSCAN_SEARCH ){
    int iCol = idxNum-FTS3_FULLTEXT_SEARCH;
    const char *zQuery = (const char *)sqlite3_value_text(apVal[0]);

    if( zQuery==0 && sqlite3_value_type(apVal[0])!=SQLITE_NULL ){
      return SQLITE_NOMEM;
    }

    pCsr->iLangid = 0;
    if( nVal==2 ) pCsr->iLangid = sqlite3_value_int(apVal[1]);

    assert( p->base.zErrMsg==0 );
    rc = sqlite3Fts3ExprParse(p->pTokenizer, pCsr->iLangid,
        p->azColumn, p->bFts4, p->nColumn, iCol, zQuery, -1, &pCsr->pExpr, 
        &p->base.zErrMsg
    );
    if( rc!=SQLITE_OK ){
................................................................................
  }

  /* Compile a SELECT statement for this cursor. For a full-table-scan, the
  ** statement loops through all rows of the %_content table. For a
  ** full-text query or docid lookup, the statement retrieves a single
  ** row by docid.
  */
  if( idxNum==FTS3_FULLSCAN_SEARCH ){
    zSql = sqlite3_mprintf(
        "SELECT %s ORDER BY rowid %s",
        p->zReadExprlist, (pCsr->bDesc ? "DESC" : "ASC")
    );
    if( zSql ){
      rc = sqlite3_prepare_v2(p->db, zSql, -1, &pCsr->pStmt, 0);
      sqlite3_free(zSql);
    }else{
      rc = SQLITE_NOMEM;
    }
  }else if( idxNum==FTS3_DOCID_SEARCH ){
    rc = fts3CursorSeekStmt(pCsr, &pCsr->pStmt);
    if( rc==SQLITE_OK ){
      rc = sqlite3_bind_value(pCsr->pStmt, 1, apVal[0]);
    }
  }
  if( rc!=SQLITE_OK ) return rc;

  return fts3NextMethod(pCursor);
}

................................................................................
      sqlite3_free(aPoslist);
    }
  }

  return SQLITE_OK;
}







/*
** This function is called for each Fts3Phrase in a full-text query 
** expression to initialize the mechanism for returning rows. Once this
** function has been called successfully on an Fts3Phrase, it may be
** used with fts3EvalPhraseNext() to iterate through the matching docids.
**
** If parameter bOptOk is true, then the phrase may (or may not) use the
** incremental loading strategy. Otherwise, the entire doclist is loaded into
** memory within this call.
**
** SQLITE_OK is returned if no error occurs, otherwise an SQLite error code.
*/
static int fts3EvalPhraseStart(Fts3Cursor *pCsr, int bOptOk, Fts3Phrase *p){
  int rc;                         /* Error code */
  Fts3PhraseToken *pFirst = &p->aToken[0];
  Fts3Table *pTab = (Fts3Table *)pCsr->base.pVtab;










  if( pCsr->bDesc==pTab->bDescIdx 
   && bOptOk==1 
   && p->nToken==1 
   && pFirst->pSegcsr 
   && pFirst->pSegcsr->bLookup 
   && pFirst->bFirst==0




  ){









    /* Use the incremental approach. */
    int iCol = (p->iColumn >= pTab->nColumn ? -1 : p->iColumn);




    rc = sqlite3Fts3MsrIncrStart(
        pTab, pFirst->pSegcsr, iCol, pFirst->z, pFirst->n);
    p->bIncr = 1;



  }else{
    /* Load the full doclist for the phrase into memory. */
    rc = fts3EvalPhraseLoad(pCsr, p);
    p->bIncr = 0;
  }

  assert( rc!=SQLITE_OK || p->nToken<1 || p->aToken[0].pSegcsr==0 || p->bIncr );
................................................................................
      p += sqlite3Fts3GetVarint(p, &iVar);
      *piDocid += ((bDescIdx ? -1 : 1) * iVar);
    }
  }

  *ppIter = p;
}



















































































































































































































/*
** Attempt to move the phrase iterator to point to the next matching docid. 
** If an error occurs, return an SQLite error code. Otherwise, return 
** SQLITE_OK.
**
** If there is no "next" entry and no error occurs, then *pbEof is set to
................................................................................
  u8 *pbEof                       /* OUT: Set to 1 if EOF */
){
  int rc = SQLITE_OK;
  Fts3Doclist *pDL = &p->doclist;
  Fts3Table *pTab = (Fts3Table *)pCsr->base.pVtab;

  if( p->bIncr ){
    assert( p->nToken==1 );
    assert( pDL->pNextDocid==0 );
    rc = sqlite3Fts3MsrIncrNext(pTab, p->aToken[0].pSegcsr, 
        &pDL->iDocid, &pDL->pList, &pDL->nList
    );
    if( rc==SQLITE_OK && !pDL->pList ){
      *pbEof = 1;
    }
  }else if( pCsr->bDesc!=pTab->bDescIdx && pDL->nAll ){
    sqlite3Fts3DoclistPrev(pTab->bDescIdx, pDL->aAll, pDL->nAll, 
        &pDL->pNextDocid, &pDL->iDocid, &pDL->nList, pbEof
    );
    pDL->pList = pDL->pNextDocid;
  }else{
    char *pIter;                            /* Used to iterate through aAll */
    char *pEnd = &pDL->aAll[pDL->nAll];     /* 1 byte past end of aAll */
    if( pDL->pNextDocid ){
      pIter = pDL->pNextDocid;
    }else{
      pIter = pDL->aAll;
    }

    if( pIter>=pEnd ){
      /* We have already reached the end of this doclist. EOF. */
      *pbEof = 1;
    }else{
      sqlite3_int64 iDelta;
      pIter += sqlite3Fts3GetVarint(pIter, &iDelta);
      if( pTab->bDescIdx==0 || pDL->pNextDocid==0 ){
        pDL->iDocid += iDelta;
      }else{
        pDL->iDocid -= iDelta;
      }
      pDL->pList = pIter;
      fts3PoslistCopy(0, &pIter);
      pDL->nList = (int)(pIter - pDL->pList);

      /* pIter now points just past the 0x00 that terminates the position-
      ** list for document pDL->iDocid. However, if this position-list was
      ** edited in place by fts3EvalNearTrim(), then pIter may not actually
      ** point to the start of the next docid value. The following line deals
      ** with this case by advancing pIter past the zero-padding added by
      ** fts3EvalNearTrim().  */
      while( pIter<pEnd && *pIter==0 ) pIter++;

      pDL->pNextDocid = pIter;
      assert( pIter>=&pDL->aAll[pDL->nAll] || *pIter );
      *pbEof = 0;
    }
  }

  return rc;
}

/*
**
................................................................................
**
** If an error occurs within this function, *pRc is set to an SQLite error
** code before returning.
*/
static void fts3EvalStartReaders(
  Fts3Cursor *pCsr,               /* FTS Cursor handle */
  Fts3Expr *pExpr,                /* Expression to initialize phrases in */
  int bOptOk,                     /* True to enable incremental loading */
  int *pRc                        /* IN/OUT: Error code */
){
  if( pExpr && SQLITE_OK==*pRc ){
    if( pExpr->eType==FTSQUERY_PHRASE ){
      int i;
      int nToken = pExpr->pPhrase->nToken;
      for(i=0; i<nToken; i++){
        if( pExpr->pPhrase->aToken[i].pDeferred==0 ) break;
      }
      pExpr->bDeferred = (i==nToken);
      *pRc = fts3EvalPhraseStart(pCsr, bOptOk, pExpr->pPhrase);
    }else{
      fts3EvalStartReaders(pCsr, pExpr->pLeft, bOptOk, pRc);
      fts3EvalStartReaders(pCsr, pExpr->pRight, bOptOk, pRc);
      pExpr->bDeferred = (pExpr->pLeft->bDeferred && pExpr->pRight->bDeferred);
    }
  }
}

/*
** An array of the following structures is assembled as part of the process
................................................................................
      pToken->pSegcsr = 0;
    }else{
      /* Set nLoad4 to the value of (4^nOther) for the next iteration of the
      ** for-loop. Except, limit the value to 2^24 to prevent it from 
      ** overflowing the 32-bit integer it is stored in. */
      if( ii<12 ) nLoad4 = nLoad4*4;

      if( ii==0 || pTC->pPhrase->nToken>1 ){
        /* Either this is the cheapest token in the entire query, or it is
        ** part of a multi-token phrase. Either way, the entire doclist will
        ** (eventually) be loaded into memory. It may as well be now. */
        Fts3PhraseToken *pToken = pTC->pToken;
        int nList = 0;
        char *pList = 0;
        rc = fts3TermSelect(pTab, pToken, pTC->iCol, &nList, &pList);
................................................................................
      }

      sqlite3_free(aTC);
    }
  }
#endif

  fts3EvalStartReaders(pCsr, pCsr->pExpr, 1, &rc);
  return rc;
}

/*
** Invalidate the current position list for phrase pPhrase.
*/
static void fts3EvalInvalidatePoslist(Fts3Phrase *pPhrase){
................................................................................
      fts3EvalNextRow(pCsr, pExpr, &rc);
      pCsr->isEof = pExpr->bEof;
      pCsr->isRequireSeek = 1;
      pCsr->isMatchinfoNeeded = 1;
      pCsr->iPrevId = pExpr->iDocid;
    }while( pCsr->isEof==0 && fts3EvalTestDeferredAndNear(pCsr, &rc) );
  }










  return rc;
}

/*
** Restart interation for expression pExpr so that the next call to
** fts3EvalNext() visits the first row. Do not allow incremental 
** loading or merging of phrase doclists for this iteration.
................................................................................
){
  if( pExpr && *pRc==SQLITE_OK ){
    Fts3Phrase *pPhrase = pExpr->pPhrase;

    if( pPhrase ){
      fts3EvalInvalidatePoslist(pPhrase);
      if( pPhrase->bIncr ){

        assert( pPhrase->nToken==1 );
        assert( pPhrase->aToken[0].pSegcsr );


        sqlite3Fts3MsrIncrRestart(pPhrase->aToken[0].pSegcsr);
        *pRc = fts3EvalPhraseStart(pCsr, 0, pPhrase);
      }



      pPhrase->doclist.pNextDocid = 0;
      pPhrase->doclist.iDocid = 0;
    }

    pExpr->iDocid = 0;
    pExpr->bEof = 0;
    pExpr->bStart = 0;
................................................................................
    return SQLITE_OK;
  }

  iDocid = pExpr->iDocid;
  pIter = pPhrase->doclist.pList;
  if( iDocid!=pCsr->iPrevId || pExpr->bEof ){
    int bDescDoclist = pTab->bDescIdx;      /* For DOCID_CMP macro */

    int bOr = 0;
    u8 bEof = 0;
    Fts3Expr *p;




    /* Check if this phrase descends from an OR expression node. If not, 
    ** return NULL. Otherwise, the entry that corresponds to docid 
    ** pCsr->iPrevId may lie earlier in the doclist buffer. */



    for(p=pExpr->pParent; p; p=p->pParent){
      if( p->eType==FTSQUERY_OR ) bOr = 1;


    }
    if( bOr==0 ) return SQLITE_OK;

    /* This is the descendent of an OR node. In this case we cannot use
    ** an incremental phrase. Load the entire doclist for the phrase
    ** into memory in this case.  */
    if( pPhrase->bIncr ){
................................................................................
        fts3EvalNextRow(pCsr, pExpr, &rc);
        if( bEofSave==0 && pExpr->iDocid==iDocid ) break;
      }
      pIter = pPhrase->doclist.pList;
      assert( rc!=SQLITE_OK || pPhrase->bIncr==0 );
      if( rc!=SQLITE_OK ) return rc;
    }



    if( pExpr->bEof ){
      pIter = 0;





      iDocid = 0;

    }

    bEof = (pPhrase->doclist.nAll==0);
    assert( bDescDoclist==0 || bDescDoclist==1 );
    assert( pCsr->bDesc==0 || pCsr->bDesc==1 );


    if( pCsr->bDesc==bDescDoclist ){
      int dummy;
















      while( (pIter==0 || DOCID_CMP(iDocid, pCsr->iPrevId)>0 ) && bEof==0 ){
        sqlite3Fts3DoclistPrev(
            bDescDoclist, pPhrase->doclist.aAll, pPhrase->doclist.nAll, 
            &pIter, &iDocid, &dummy, &bEof
        );
      }
    }else{




      while( (pIter==0 || DOCID_CMP(iDocid, pCsr->iPrevId)<0 ) && bEof==0 ){
        sqlite3Fts3DoclistNext(
            bDescDoclist, pPhrase->doclist.aAll, pPhrase->doclist.nAll, 
            &pIter, &iDocid, &bEof
        );

      }
    }

    if( bEof || iDocid!=pCsr->iPrevId ) pIter = 0;
  }
  if( pIter==0 ) return SQLITE_OK;

................................................................................
  p->bAutoincrmerge = fts3Getint(&zParam)!=0;
  if( !p->bHasStat ){
    assert( p->bFts4==0 );
    sqlite3Fts3CreateStatTable(&rc, p);
    if( rc ) return rc;
  }
  rc = fts3SqlStmt(p, SQL_REPLACE_STAT, &pStmt, 0);
  if( rc ) return rc;;
  sqlite3_bind_int(pStmt, 1, FTS_STAT_AUTOINCRMERGE);
  sqlite3_bind_int(pStmt, 2, p->bAutoincrmerge);
  sqlite3_step(pStmt);
  rc = sqlite3_reset(pStmt);
  return rc;
}

................................................................................
    rc = fts3DoAutoincrmerge(p, &zVal[10]);
#ifdef SQLITE_TEST
  }else if( nVal>9 && 0==sqlite3_strnicmp(zVal, "nodesize=", 9) ){
    p->nNodeSize = atoi(&zVal[9]);
    rc = SQLITE_OK;
  }else if( nVal>11 && 0==sqlite3_strnicmp(zVal, "maxpending=", 9) ){
    p->nMaxPendingData = atoi(&zVal[11]);



    rc = SQLITE_OK;
#endif
  }else{
    rc = SQLITE_ERROR;
  }

  return rc;

/******************************************************************************
** This file is an amalgamation of many separate C source files from SQLite
** version 3.8.1.  By combining all the individual C code files into this 
** single large file, the entire code can be compiled as a single translation
** unit.  This allows many compilers to do optimizations that would not be
** possible if the files were compiled separately.  Performance improvements
** of 5% or more are commonly seen when SQLite is compiled as a single
** translation unit.
**
** This file is all you need to compile SQLite.  To use SQLite in other
................................................................................
#define SQLITE_AMALGAMATION 1
#ifndef SQLITE_PRIVATE
# define SQLITE_PRIVATE static
#endif
#ifndef SQLITE_API
# define SQLITE_API
#endif









































































































































































































































































































































































































































































































































/************** Begin file sqlite3.h *****************************************/
/*
** 2001 September 15
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
................................................................................
** string contains the date and time of the check-in (UTC) and an SHA1
** hash of the entire source tree.
**
** See also: [sqlite3_libversion()],
** [sqlite3_libversion_number()], [sqlite3_sourceid()],
** [sqlite_version()] and [sqlite_source_id()].
*/
#define SQLITE_VERSION        "3.8.1"
#define SQLITE_VERSION_NUMBER 3008001
#define SQLITE_SOURCE_ID      "2013-10-14 13:21:00 1660efbe46439734c7dc1674994ceb86a9b41d1a"

/*
** CAPI3REF: Run-Time Library Version Numbers
** KEYWORDS: sqlite3_version, sqlite3_sourceid
**
** These interfaces provide the same information as the [SQLITE_VERSION],
** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
................................................................................
#define SQLITE_IOERR_SHMSIZE           (SQLITE_IOERR | (19<<8))
#define SQLITE_IOERR_SHMLOCK           (SQLITE_IOERR | (20<<8))
#define SQLITE_IOERR_SHMMAP            (SQLITE_IOERR | (21<<8))
#define SQLITE_IOERR_SEEK              (SQLITE_IOERR | (22<<8))
#define SQLITE_IOERR_DELETE_NOENT      (SQLITE_IOERR | (23<<8))
#define SQLITE_IOERR_MMAP              (SQLITE_IOERR | (24<<8))
#define SQLITE_IOERR_GETTEMPPATH       (SQLITE_IOERR | (25<<8))
#define SQLITE_IOERR_CONVPATH          (SQLITE_IOERR | (26<<8))
#define SQLITE_LOCKED_SHAREDCACHE      (SQLITE_LOCKED |  (1<<8))
#define SQLITE_BUSY_RECOVERY           (SQLITE_BUSY   |  (1<<8))
#define SQLITE_BUSY_SNAPSHOT           (SQLITE_BUSY   |  (2<<8))
#define SQLITE_CANTOPEN_NOTEMPDIR      (SQLITE_CANTOPEN | (1<<8))
#define SQLITE_CANTOPEN_ISDIR          (SQLITE_CANTOPEN | (2<<8))
#define SQLITE_CANTOPEN_FULLPATH       (SQLITE_CANTOPEN | (3<<8))
#define SQLITE_CANTOPEN_CONVPATH       (SQLITE_CANTOPEN | (4<<8))
#define SQLITE_CORRUPT_VTAB            (SQLITE_CORRUPT | (1<<8))
#define SQLITE_READONLY_RECOVERY       (SQLITE_READONLY | (1<<8))
#define SQLITE_READONLY_CANTLOCK       (SQLITE_READONLY | (2<<8))
#define SQLITE_READONLY_ROLLBACK       (SQLITE_READONLY | (3<<8))
#define SQLITE_ABORT_ROLLBACK          (SQLITE_ABORT | (2<<8))
#define SQLITE_CONSTRAINT_CHECK        (SQLITE_CONSTRAINT | (1<<8))
#define SQLITE_CONSTRAINT_COMMITHOOK   (SQLITE_CONSTRAINT | (2<<8))
................................................................................
** log message after formatting via [sqlite3_snprintf()].
** The SQLite logging interface is not reentrant; the logger function
** supplied by the application must not invoke any SQLite interface.
** In a multi-threaded application, the application-defined logger
** function must be threadsafe. </dd>
**
** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI
** <dd>^(This option takes a single argument of type int. If non-zero, then
** URI handling is globally enabled. If the parameter is zero, then URI handling
** is globally disabled.)^ ^If URI handling is globally enabled, all filenames
** passed to [sqlite3_open()], [sqlite3_open_v2()], [sqlite3_open16()] or
** specified as part of [ATTACH] commands are interpreted as URIs, regardless
** of whether or not the [SQLITE_OPEN_URI] flag is set when the database
** connection is opened. ^If it is globally disabled, filenames are
** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the
** database connection is opened. ^(By default, URI handling is globally
** disabled. The default value may be changed by compiling with the
** [SQLITE_USE_URI] symbol defined.)^
**
** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN
** <dd>^This option takes a single integer argument which is interpreted as
** a boolean in order to enable or disable the use of covering indices for
** full table scans in the query optimizer.  ^The default setting is determined
** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on"
** if that compile-time option is omitted.
** The ability to disable the use of covering indices for full table scans
** is because some incorrectly coded legacy applications might malfunction
** when the optimization is enabled.  Providing the ability to
** disable the optimization allows the older, buggy application code to work
** without change even with newer versions of SQLite.
**
** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE
** <dd> These options are obsolete and should not be used by new code.
** They are retained for backwards compatibility but are now no-ops.
................................................................................
** the connection being passed as the second parameter is being closed. The
** third parameter is passed NULL In this case.  An example of using this
** configuration option can be seen in the "test_sqllog.c" source file in
** the canonical SQLite source tree.</dd>
**
** [[SQLITE_CONFIG_MMAP_SIZE]]
** <dt>SQLITE_CONFIG_MMAP_SIZE
** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values
** that are the default mmap size limit (the default setting for
** [PRAGMA mmap_size]) and the maximum allowed mmap size limit.
** ^The default setting can be overridden by each database connection using
** either the [PRAGMA mmap_size] command, or by using the
** [SQLITE_FCNTL_MMAP_SIZE] file control.  ^(The maximum allowed mmap size
** cannot be changed at run-time.  Nor may the maximum allowed mmap size
** exceed the compile-time maximum mmap size set by the
** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^
** ^If either argument to this option is negative, then that argument is
** changed to its compile-time default.
** </dl>
*/
#define SQLITE_CONFIG_SINGLETHREAD  1  /* nil */
#define SQLITE_CONFIG_MULTITHREAD   2  /* nil */
#define SQLITE_CONFIG_SERIALIZED    3  /* nil */
#define SQLITE_CONFIG_MALLOC        4  /* sqlite3_mem_methods* */
................................................................................
}  /* end of the 'extern "C"' block */
#endif

#endif  /* ifndef _SQLITE3RTREE_H_ */


/************** End of sqlite3.h *********************************************/
/************** Begin file sqliteInt.h ***************************************/
/*
** 2001 September 15
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_

/*
** These #defines should enable >2GB file support on POSIX if the
** underlying operating system supports it.  If the OS lacks
** large file support, or if the OS is windows, these should be no-ops.
**
** Ticket #2739:  The _LARGEFILE_SOURCE macro must appear before any
** system #includes.  Hence, this block of code must be the very first
** code in all source files.
**
** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch
** on the compiler command line.  This is necessary if you are compiling
** on a recent machine (ex: Red Hat 7.2) but you want your code to work
** on an older machine (ex: Red Hat 6.0).  If you compile on Red Hat 7.2
** without this option, LFS is enable.  But LFS does not exist in the kernel
** in Red Hat 6.0, so the code won't work.  Hence, for maximum binary
** portability you should omit LFS.
**
** Similar is true for Mac OS X.  LFS is only supported on Mac OS X 9 and later.
*/
#ifndef SQLITE_DISABLE_LFS
# define _LARGE_FILE       1
# ifndef _FILE_OFFSET_BITS
#   define _FILE_OFFSET_BITS 64
# endif
# define _LARGEFILE_SOURCE 1
#endif

/*
** Include the configuration header output by 'configure' if we're using the
** autoconf-based build
*/
#ifdef _HAVE_SQLITE_CONFIG_H
#include "config.h"
#endif

/************** Include sqliteLimit.h in the middle of sqliteInt.h ***********/
/************** Begin file sqliteLimit.h *************************************/
/*
** 2007 May 7
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** 
** This file defines various limits of what SQLite can process.
*/

/*
** The maximum length of a TEXT or BLOB in bytes.   This also
** limits the size of a row in a table or index.
**
** The hard limit is the ability of a 32-bit signed integer
** to count the size: 2^31-1 or 2147483647.
*/
#ifndef SQLITE_MAX_LENGTH
# define SQLITE_MAX_LENGTH 1000000000
#endif

/*
** This is the maximum number of
**
**    * Columns in a table
**    * Columns in an index
**    * Columns in a view
**    * Terms in the SET clause of an UPDATE statement
**    * Terms in the result set of a SELECT statement
**    * Terms in the GROUP BY or ORDER BY clauses of a SELECT statement.
**    * Terms in the VALUES clause of an INSERT statement
**
** The hard upper limit here is 32676.  Most database people will
** tell you that in a well-normalized database, you usually should
** not have more than a dozen or so columns in any table.  And if
** that is the case, there is no point in having more than a few
** dozen values in any of the other situations described above.
*/
#ifndef SQLITE_MAX_COLUMN
# define SQLITE_MAX_COLUMN 2000
#endif

/*
** The maximum length of a single SQL statement in bytes.
**
** It used to be the case that setting this value to zero would
** turn the limit off.  That is no longer true.  It is not possible
** to turn this limit off.
*/
#ifndef SQLITE_MAX_SQL_LENGTH
# define SQLITE_MAX_SQL_LENGTH 1000000000
#endif

/*
** The maximum depth of an expression tree. This is limited to 
** some extent by SQLITE_MAX_SQL_LENGTH. But sometime you might 
** want to place more severe limits on the complexity of an 
** expression.
**
** A value of 0 used to mean that the limit was not enforced.
** But that is no longer true.  The limit is now strictly enforced
** at all times.
*/
#ifndef SQLITE_MAX_EXPR_DEPTH
# define SQLITE_MAX_EXPR_DEPTH 1000
#endif

/*
** The maximum number of terms in a compound SELECT statement.
** The code generator for compound SELECT statements does one
** level of recursion for each term.  A stack overflow can result
** if the number of terms is too large.  In practice, most SQL
** never has more than 3 or 4 terms.  Use a value of 0 to disable
** any limit on the number of terms in a compount SELECT.
*/
#ifndef SQLITE_MAX_COMPOUND_SELECT
# define SQLITE_MAX_COMPOUND_SELECT 500
#endif

/*
** The maximum number of opcodes in a VDBE program.
** Not currently enforced.
*/
#ifndef SQLITE_MAX_VDBE_OP
# define SQLITE_MAX_VDBE_OP 25000
#endif

/*
** The maximum number of arguments to an SQL function.
*/
#ifndef SQLITE_MAX_FUNCTION_ARG
# define SQLITE_MAX_FUNCTION_ARG 127
#endif

/*
** The maximum number of in-memory pages to use for the main database
** table and for temporary tables.  The SQLITE_DEFAULT_CACHE_SIZE
*/
#ifndef SQLITE_DEFAULT_CACHE_SIZE
# define SQLITE_DEFAULT_CACHE_SIZE  2000
#endif
#ifndef SQLITE_DEFAULT_TEMP_CACHE_SIZE
# define SQLITE_DEFAULT_TEMP_CACHE_SIZE  500
#endif

/*
** The default number of frames to accumulate in the log file before
** checkpointing the database in WAL mode.
*/
#ifndef SQLITE_DEFAULT_WAL_AUTOCHECKPOINT
# define SQLITE_DEFAULT_WAL_AUTOCHECKPOINT  1000
#endif

/*
** The maximum number of attached databases.  This must be between 0
** and 62.  The upper bound on 62 is because a 64-bit integer bitmap
** is used internally to track attached databases.
*/
#ifndef SQLITE_MAX_ATTACHED
# define SQLITE_MAX_ATTACHED 10
#endif


/*
** The maximum value of a ?nnn wildcard that the parser will accept.
*/
#ifndef SQLITE_MAX_VARIABLE_NUMBER
# define SQLITE_MAX_VARIABLE_NUMBER 999
#endif

/* Maximum page size.  The upper bound on this value is 65536.  This a limit
** imposed by the use of 16-bit offsets within each page.
**
** Earlier versions of SQLite allowed the user to change this value at
** compile time. This is no longer permitted, on the grounds that it creates
** a library that is technically incompatible with an SQLite library 
** compiled with a different limit. If a process operating on a database 
** with a page-size of 65536 bytes crashes, then an instance of SQLite 
** compiled with the default page-size limit will not be able to rollback 
** the aborted transaction. This could lead to database corruption.
*/
#ifdef SQLITE_MAX_PAGE_SIZE
# undef SQLITE_MAX_PAGE_SIZE
#endif
#define SQLITE_MAX_PAGE_SIZE 65536


/*
** The default size of a database page.
*/
#ifndef SQLITE_DEFAULT_PAGE_SIZE
# define SQLITE_DEFAULT_PAGE_SIZE 1024
#endif
#if SQLITE_DEFAULT_PAGE_SIZE>SQLITE_MAX_PAGE_SIZE
# undef SQLITE_DEFAULT_PAGE_SIZE
# define SQLITE_DEFAULT_PAGE_SIZE SQLITE_MAX_PAGE_SIZE
#endif

/*
** Ordinarily, if no value is explicitly provided, SQLite creates databases
** with page size SQLITE_DEFAULT_PAGE_SIZE. However, based on certain
** device characteristics (sector-size and atomic write() support),
** SQLite may choose a larger value. This constant is the maximum value
** SQLite will choose on its own.
*/
#ifndef SQLITE_MAX_DEFAULT_PAGE_SIZE
# define SQLITE_MAX_DEFAULT_PAGE_SIZE 8192
#endif
#if SQLITE_MAX_DEFAULT_PAGE_SIZE>SQLITE_MAX_PAGE_SIZE
# undef SQLITE_MAX_DEFAULT_PAGE_SIZE
# define SQLITE_MAX_DEFAULT_PAGE_SIZE SQLITE_MAX_PAGE_SIZE
#endif


/*
** Maximum number of pages in one database file.
**
** This is really just the default value for the max_page_count pragma.
** This value can be lowered (or raised) at run-time using that the
** max_page_count macro.
*/
#ifndef SQLITE_MAX_PAGE_COUNT
# define SQLITE_MAX_PAGE_COUNT 1073741823
#endif

/*
** Maximum length (in bytes) of the pattern in a LIKE or GLOB
** operator.
*/
#ifndef SQLITE_MAX_LIKE_PATTERN_LENGTH
# define SQLITE_MAX_LIKE_PATTERN_LENGTH 50000
#endif

/*
** Maximum depth of recursion for triggers.
**
** A value of 1 means that a trigger program will not be able to itself
** fire any triggers. A value of 0 means that no trigger programs at all 
** may be executed.
*/
#ifndef SQLITE_MAX_TRIGGER_DEPTH
# define SQLITE_MAX_TRIGGER_DEPTH 1000
#endif

/************** End of sqliteLimit.h *****************************************/
/************** Continuing where we left off in sqliteInt.h ******************/

/* Disable nuisance warnings on Borland compilers */
#if defined(__BORLANDC__)
#pragma warn -rch /* unreachable code */
#pragma warn -ccc /* Condition is always true or false */
#pragma warn -aus /* Assigned value is never used */
#pragma warn -csu /* Comparing signed and unsigned */
#pragma warn -spa /* Suspicious pointer arithmetic */
#endif

/* Needed for various definitions... */
#ifndef _GNU_SOURCE
# define _GNU_SOURCE
#endif

#if defined(__OpenBSD__) && !defined(_BSD_SOURCE)
# define _BSD_SOURCE
#endif

/*
** Include standard header files as necessary
*/
#ifdef HAVE_STDINT_H
#include <stdint.h>
#endif
#ifdef HAVE_INTTYPES_H
#include <inttypes.h>
#endif

/*
** The following macros are used to cast pointers to integers and
** integers to pointers.  The way you do this varies from one compiler
** to the next, so we have developed the following set of #if statements
** to generate appropriate macros for a wide range of compilers.
**
** The correct "ANSI" way to do this is to use the intptr_t type. 
** Unfortunately, that typedef is not available on all compilers, or
** if it is available, it requires an #include of specific headers
** that vary from one machine to the next.
**
** Ticket #3860:  The llvm-gcc-4.2 compiler from Apple chokes on
** the ((void*)&((char*)0)[X]) construct.  But MSVC chokes on ((void*)(X)).
** So we have to define the macros in different ways depending on the
** compiler.
*/
#if defined(__PTRDIFF_TYPE__)  /* This case should work for GCC */
# define SQLITE_INT_TO_PTR(X)  ((void*)(__PTRDIFF_TYPE__)(X))
# define SQLITE_PTR_TO_INT(X)  ((int)(__PTRDIFF_TYPE__)(X))
#elif !defined(__GNUC__)       /* Works for compilers other than LLVM */
# define SQLITE_INT_TO_PTR(X)  ((void*)&((char*)0)[X])
# define SQLITE_PTR_TO_INT(X)  ((int)(((char*)X)-(char*)0))
#elif defined(HAVE_STDINT_H)   /* Use this case if we have ANSI headers */
# define SQLITE_INT_TO_PTR(X)  ((void*)(intptr_t)(X))
# define SQLITE_PTR_TO_INT(X)  ((int)(intptr_t)(X))
#else                          /* Generates a warning - but it always works */
# define SQLITE_INT_TO_PTR(X)  ((void*)(X))
# define SQLITE_PTR_TO_INT(X)  ((int)(X))
#endif

/*
** The SQLITE_THREADSAFE macro must be defined as 0, 1, or 2.
** 0 means mutexes are permanently disable and the library is never
** threadsafe.  1 means the library is serialized which is the highest
** level of threadsafety.  2 means the library is multithreaded - multiple
** threads can use SQLite as long as no two threads try to use the same
** database connection at the same time.
**
** Older versions of SQLite used an optional THREADSAFE macro.
** We support that for legacy.
*/
#if !defined(SQLITE_THREADSAFE)
# if defined(THREADSAFE)
#   define SQLITE_THREADSAFE THREADSAFE
# else
#   define SQLITE_THREADSAFE 1 /* IMP: R-07272-22309 */
# endif
#endif

/*
** Powersafe overwrite is on by default.  But can be turned off using
** the -DSQLITE_POWERSAFE_OVERWRITE=0 command-line option.
*/
#ifndef SQLITE_POWERSAFE_OVERWRITE
# define SQLITE_POWERSAFE_OVERWRITE 1
#endif

/*
** The SQLITE_DEFAULT_MEMSTATUS macro must be defined as either 0 or 1.
** It determines whether or not the features related to 
** SQLITE_CONFIG_MEMSTATUS are available by default or not. This value can
** be overridden at runtime using the sqlite3_config() API.
*/
#if !defined(SQLITE_DEFAULT_MEMSTATUS)
# define SQLITE_DEFAULT_MEMSTATUS 1
#endif

/*
** Exactly one of the following macros must be defined in order to
** specify which memory allocation subsystem to use.
**
**     SQLITE_SYSTEM_MALLOC          // Use normal system malloc()
**     SQLITE_WIN32_MALLOC           // Use Win32 native heap API
**     SQLITE_ZERO_MALLOC            // Use a stub allocator that always fails
**     SQLITE_MEMDEBUG               // Debugging version of system malloc()
**
** On Windows, if the SQLITE_WIN32_MALLOC_VALIDATE macro is defined and the
** assert() macro is enabled, each call into the Win32 native heap subsystem
** will cause HeapValidate to be called.  If heap validation should fail, an
** assertion will be triggered.
**
** If none of the above are defined, then set SQLITE_SYSTEM_MALLOC as
** the default.
*/
#if defined(SQLITE_SYSTEM_MALLOC) \
  + defined(SQLITE_WIN32_MALLOC) \
  + defined(SQLITE_ZERO_MALLOC) \
  + defined(SQLITE_MEMDEBUG)>1
# error "Two or more of the following compile-time configuration options\
 are defined but at most one is allowed:\
 SQLITE_SYSTEM_MALLOC, SQLITE_WIN32_MALLOC, SQLITE_MEMDEBUG,\
 SQLITE_ZERO_MALLOC"
#endif
#if defined(SQLITE_SYSTEM_MALLOC) \
  + defined(SQLITE_WIN32_MALLOC) \
  + defined(SQLITE_ZERO_MALLOC) \
  + defined(SQLITE_MEMDEBUG)==0
# define SQLITE_SYSTEM_MALLOC 1
#endif

/*
** If SQLITE_MALLOC_SOFT_LIMIT is not zero, then try to keep the
** sizes of memory allocations below this value where possible.
*/
#if !defined(SQLITE_MALLOC_SOFT_LIMIT)
# define SQLITE_MALLOC_SOFT_LIMIT 1024
#endif

/*
** We need to define _XOPEN_SOURCE as follows in order to enable
** recursive mutexes on most Unix systems and fchmod() on OpenBSD.
** But _XOPEN_SOURCE define causes problems for Mac OS X, so omit
** it.
*/
#if !defined(_XOPEN_SOURCE) && !defined(__DARWIN__) && !defined(__APPLE__)
#  define _XOPEN_SOURCE 600
#endif

/*
** NDEBUG and SQLITE_DEBUG are opposites.  It should always be true that
** defined(NDEBUG)==!defined(SQLITE_DEBUG).  If this is not currently true,
** make it true by defining or undefining NDEBUG.
**
** Setting NDEBUG makes the code smaller and faster by disabling the
** assert() statements in the code.  So we want the default action
** to be for NDEBUG to be set and NDEBUG to be undefined only if SQLITE_DEBUG
** is set.  Thus NDEBUG becomes an opt-in rather than an opt-out
** feature.
*/
#if !defined(NDEBUG) && !defined(SQLITE_DEBUG) 
# define NDEBUG 1
#endif
#if defined(NDEBUG) && defined(SQLITE_DEBUG)
# undef NDEBUG
#endif

/*
** The testcase() macro is used to aid in coverage testing.  When 
** doing coverage testing, the condition inside the argument to
** testcase() must be evaluated both true and false in order to
** get full branch coverage.  The testcase() macro is inserted
** to help ensure adequate test coverage in places where simple
** condition/decision coverage is inadequate.  For example, testcase()
** can be used to make sure boundary values are tested.  For
** bitmask tests, testcase() can be used to make sure each bit
** is significant and used at least once.  On switch statements
** where multiple cases go to the same block of code, testcase()
** can insure that all cases are evaluated.
**
*/
#ifdef SQLITE_COVERAGE_TEST
SQLITE_PRIVATE   void sqlite3Coverage(int);
# define testcase(X)  if( X ){ sqlite3Coverage(__LINE__); }
#else
# define testcase(X)
#endif

/*
** The TESTONLY macro is used to enclose variable declarations or
** other bits of code that are needed to support the arguments
** within testcase() and assert() macros.
*/
#if !defined(NDEBUG) || defined(SQLITE_COVERAGE_TEST)
# define TESTONLY(X)  X
#else
# define TESTONLY(X)
#endif

/*
** Sometimes we need a small amount of code such as a variable initialization
** to setup for a later assert() statement.  We do not want this code to
** appear when assert() is disabled.  The following macro is therefore
** used to contain that setup code.  The "VVA" acronym stands for
** "Verification, Validation, and Accreditation".  In other words, the
** code within VVA_ONLY() will only run during verification processes.
*/
#ifndef NDEBUG
# define VVA_ONLY(X)  X
#else
# define VVA_ONLY(X)
#endif

/*
** The ALWAYS and NEVER macros surround boolean expressions which 
** are intended to always be true or false, respectively.  Such
** expressions could be omitted from the code completely.  But they
** are included in a few cases in order to enhance the resilience
** of SQLite to unexpected behavior - to make the code "self-healing"
** or "ductile" rather than being "brittle" and crashing at the first
** hint of unplanned behavior.
**
** In other words, ALWAYS and NEVER are added for defensive code.
**
** When doing coverage testing ALWAYS and NEVER are hard-coded to
** be true and false so that the unreachable code they specify will
** not be counted as untested code.
*/
#if defined(SQLITE_COVERAGE_TEST)
# define ALWAYS(X)      (1)
# define NEVER(X)       (0)
#elif !defined(NDEBUG)
# define ALWAYS(X)      ((X)?1:(assert(0),0))
# define NEVER(X)       ((X)?(assert(0),1):0)
#else
# define ALWAYS(X)      (X)
# define NEVER(X)       (X)
#endif

/*
** Return true (non-zero) if the input is a integer that is too large
** to fit in 32-bits.  This macro is used inside of various testcase()
** macros to verify that we have tested SQLite for large-file support.
*/
#define IS_BIG_INT(X)  (((X)&~(i64)0xffffffff)!=0)

/*
** The macro unlikely() is a hint that surrounds a boolean
** expression that is usually false.  Macro likely() surrounds
** a boolean expression that is usually true.  These hints could,
** in theory, be used by the compiler to generate better code, but
** currently they are just comments for human readers.
*/
#define likely(X)    (X)
#define unlikely(X)  (X)

/************** Include hash.h in the middle of sqliteInt.h ******************/
/************** Begin file hash.h ********************************************/
/*
** 2001 September 22
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
................................................................................
*/
#ifdef SQLITE_64BIT_STATS
 typedef u64 tRowcnt;    /* 64-bit only if requested at compile-time */
#else
 typedef u32 tRowcnt;    /* 32-bit is the default */
#endif

/*
** Estimated quantities used for query planning are stored as 16-bit
** logarithms.  For quantity X, the value stored is 10*log2(X).  This
** gives a possible range of values of approximately 1.0e986 to 1e-986.
** But the allowed values are "grainy".  Not every value is representable.
** For example, quantities 16 and 17 are both represented by a LogEst
** of 40.  However, since LogEst quantatites are suppose to be estimates,
** not exact values, this imprecision is not a problem.
**
** "LogEst" is short for "Logarithimic Estimate".
**
** Examples:
**      1 -> 0              20 -> 43          10000 -> 132
**      2 -> 10             25 -> 46          25000 -> 146
**      3 -> 16            100 -> 66        1000000 -> 199
**      4 -> 20           1000 -> 99        1048576 -> 200
**     10 -> 33           1024 -> 100    4294967296 -> 320
**
** The LogEst can be negative to indicate fractional values. 
** Examples:
**
**    0.5 -> -10           0.1 -> -33        0.0625 -> -40
*/
typedef INT16_TYPE LogEst;

/*
** Macros to determine whether the machine is big or little endian,
** evaluated at runtime.
*/
#ifdef SQLITE_AMALGAMATION
SQLITE_PRIVATE const int sqlite3one = 1;
#else
................................................................................
# define SQLITE_DEFAULT_MMAP_SIZE_xc 1  /* Exclude from ctime.c */
#endif
#if SQLITE_DEFAULT_MMAP_SIZE>SQLITE_MAX_MMAP_SIZE
# undef SQLITE_DEFAULT_MMAP_SIZE
# define SQLITE_DEFAULT_MMAP_SIZE SQLITE_MAX_MMAP_SIZE
#endif

/*
** Only one of SQLITE_ENABLE_STAT3 or SQLITE_ENABLE_STAT4 can be defined.
** Priority is given to SQLITE_ENABLE_STAT4.  If either are defined, also
** define SQLITE_ENABLE_STAT3_OR_STAT4
*/
#ifdef SQLITE_ENABLE_STAT4
# undef SQLITE_ENABLE_STAT3
# define SQLITE_ENABLE_STAT3_OR_STAT4 1
#elif SQLITE_ENABLE_STAT3
# define SQLITE_ENABLE_STAT3_OR_STAT4 1
#elif SQLITE_ENABLE_STAT3_OR_STAT4
# undef SQLITE_ENABLE_STAT3_OR_STAT4
#endif

/*
** An instance of the following structure is used to store the busy-handler
** callback for a given sqlite handle. 
**
** The sqlite.busyHandler member of the sqlite struct contains the busy
** callback for the database handle. Each pager opened via the sqlite
** handle is passed a pointer to sqlite.busyHandler. The busy-handler
................................................................................
  int (*xWalCallback)(void *, sqlite3 *, const char *, int);
  void *pWalArg;
#endif
  void(*xCollNeeded)(void*,sqlite3*,int eTextRep,const char*);
  void(*xCollNeeded16)(void*,sqlite3*,int eTextRep,const void*);
  void *pCollNeededArg;
  sqlite3_value *pErr;          /* Most recent error message */


  union {
    volatile int isInterrupted; /* True if sqlite3_interrupt has been called */
    double notUsed1;            /* Spacer */
  } u1;
  Lookaside lookaside;          /* Lookaside malloc configuration */
#ifndef SQLITE_OMIT_AUTHORIZATION
  int (*xAuth)(void*,int,const char*,const char*,const char*,const char*);
................................................................................
#define SQLITE_DistinctOpt    0x0020   /* DISTINCT using indexes */
#define SQLITE_CoverIdxScan   0x0040   /* Covering index scans */
#define SQLITE_OrderByIdxJoin 0x0080   /* ORDER BY of joins via index */
#define SQLITE_SubqCoroutine  0x0100   /* Evaluate subqueries as coroutines */
#define SQLITE_Transitive     0x0200   /* Transitive constraints */
#define SQLITE_OmitNoopJoin   0x0400   /* Omit unused tables in joins */
#define SQLITE_Stat3          0x0800   /* Use the SQLITE_STAT3 table */
#define SQLITE_AdjustOutEst   0x1000   /* Adjust output estimates using WHERE */
#define SQLITE_AllOpts        0xffff   /* All optimizations */

/*
** Macros for testing whether or not optimizations are enabled or disabled.
*/
#ifndef SQLITE_OMIT_BUILTIN_TEST
#define OptimizationDisabled(db, mask)  (((db)->dbOptFlags&(mask))!=0)
................................................................................
** Each SQL function is defined by an instance of the following
** structure.  A pointer to this structure is stored in the sqlite.aFunc
** hash table.  When multiple functions have the same name, the hash table
** points to a linked list of these structures.
*/
struct FuncDef {
  i16 nArg;            /* Number of arguments.  -1 means unlimited */

  u16 funcFlags;       /* Some combination of SQLITE_FUNC_* */
  void *pUserData;     /* User data parameter */
  FuncDef *pNext;      /* Next function with same name */
  void (*xFunc)(sqlite3_context*,int,sqlite3_value**); /* Regular function */
  void (*xStep)(sqlite3_context*,int,sqlite3_value**); /* Aggregate step */
  void (*xFinalize)(sqlite3_context*);                /* Aggregate finalizer */
  char *zName;         /* SQL name of the function. */
  FuncDef *pHash;      /* Next with a different name but the same hash */
................................................................................
};

/*
** Possible values for FuncDef.flags.  Note that the _LENGTH and _TYPEOF
** values must correspond to OPFLAG_LENGTHARG and OPFLAG_TYPEOFARG.  There
** are assert() statements in the code to verify this.
*/
#define SQLITE_FUNC_ENCMASK  0x003 /* SQLITE_UTF8, SQLITE_UTF16BE or UTF16LE */
#define SQLITE_FUNC_LIKE     0x004 /* Candidate for the LIKE optimization */
#define SQLITE_FUNC_CASE     0x008 /* Case-sensitive LIKE-type function */
#define SQLITE_FUNC_EPHEM    0x010 /* Ephemeral.  Delete with VDBE */
#define SQLITE_FUNC_NEEDCOLL 0x020 /* sqlite3GetFuncCollSeq() might be called */


#define SQLITE_FUNC_LENGTH   0x040 /* Built-in length() function */
#define SQLITE_FUNC_TYPEOF   0x080 /* Built-in typeof() function */
#define SQLITE_FUNC_COUNT    0x100 /* Built-in count(*) aggregate */
#define SQLITE_FUNC_COALESCE 0x200 /* Built-in coalesce() or ifnull() */
#define SQLITE_FUNC_UNLIKELY 0x400 /* Built-in unlikely() function */

/*
** The following three macros, FUNCTION(), LIKEFUNC() and AGGREGATE() are
** used to create the initializers for the FuncDef structures.
**
**   FUNCTION(zName, nArg, iArg, bNC, xFunc)
**     Used to create a scalar function definition of a function zName 
................................................................................
**     that accepts nArg arguments and is implemented by a call to C 
**     function likeFunc. Argument pArg is cast to a (void *) and made
**     available as the function user-data (sqlite3_user_data()). The
**     FuncDef.flags variable is set to the value passed as the flags
**     parameter.
*/
#define FUNCTION(zName, nArg, iArg, bNC, xFunc) \
  {nArg, SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
   SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, #zName, 0, 0}
#define FUNCTION2(zName, nArg, iArg, bNC, xFunc, extraFlags) \
  {nArg, SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL)|extraFlags, \
   SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, #zName, 0, 0}
#define STR_FUNCTION(zName, nArg, pArg, bNC, xFunc) \
  {nArg, SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
   pArg, 0, xFunc, 0, 0, #zName, 0, 0}
#define LIKEFUNC(zName, nArg, arg, flags) \
  {nArg, SQLITE_UTF8|flags, (void *)arg, 0, likeFunc, 0, 0, #zName, 0, 0}
#define AGGREGATE(zName, nArg, arg, nc, xStep, xFinal) \
  {nArg, SQLITE_UTF8|(nc*SQLITE_FUNC_NEEDCOLL), \
   SQLITE_INT_TO_PTR(arg), 0, 0, xStep,xFinal,#zName,0,0}

/*
** All current savepoints are stored in a linked list starting at
** sqlite3.pSavepoint. The first element in the list is the most recently
** opened savepoint. Savepoints are added to the list by the vdbe
** OP_Savepoint instruction.
................................................................................
  char *zName;     /* Name of this column */
  Expr *pDflt;     /* Default value of this column */
  char *zDflt;     /* Original text of the default value */
  char *zType;     /* Data type for this column */
  char *zColl;     /* Collating sequence.  If NULL, use the default */
  u8 notNull;      /* An OE_ code for handling a NOT NULL constraint */
  char affinity;   /* One of the SQLITE_AFF_... values */
  u8 szEst;        /* Estimated size of this column.  INT==1 */
  u8 colFlags;     /* Boolean properties.  See COLFLAG_ defines below */
};

/* Allowed values for Column.colFlags:
*/
#define COLFLAG_PRIMKEY  0x0001    /* Column is part of the primary key */
#define COLFLAG_HIDDEN   0x0002    /* A hidden column in a virtual table */

................................................................................
  ExprList *pCheck;    /* All CHECK constraints */
#endif
  tRowcnt nRowEst;     /* Estimated rows in table - from sqlite_stat1 table */
  int tnum;            /* Root BTree node for this table (see note above) */
  i16 iPKey;           /* If not negative, use aCol[iPKey] as the primary key */
  i16 nCol;            /* Number of columns in this table */
  u16 nRef;            /* Number of pointers to this Table */
  LogEst szTabRow;     /* Estimated size of each table row in bytes */
  u8 tabFlags;         /* Mask of TF_* values */
  u8 keyConf;          /* What to do in case of uniqueness conflict on iPKey */
#ifndef SQLITE_OMIT_ALTERTABLE
  int addColOffset;    /* Offset in CREATE TABLE stmt to add a new column */
#endif
#ifndef SQLITE_OMIT_VIRTUALTABLE
  int nModuleArg;      /* Number of arguments to the module */
................................................................................
#define OE_Replace  5   /* Delete existing record, then do INSERT or UPDATE */

#define OE_Restrict 6   /* OE_Abort for IMMEDIATE, OE_Rollback for DEFERRED */
#define OE_SetNull  7   /* Set the foreign key value to NULL */
#define OE_SetDflt  8   /* Set the foreign key value to its default */
#define OE_Cascade  9   /* Cascade the changes */

#define OE_Default  10  /* Do whatever the default action is */


/*
** An instance of the following structure is passed as the first
** argument to sqlite3VdbeKeyCompare and is used to control the 
** comparison of the two index keys.
**
................................................................................
  char *zColAff;           /* String defining the affinity of each column */
  Index *pNext;            /* The next index associated with the same table */
  Schema *pSchema;         /* Schema containing this index */
  u8 *aSortOrder;          /* for each column: True==DESC, False==ASC */
  char **azColl;           /* Array of collation sequence names for index */
  Expr *pPartIdxWhere;     /* WHERE clause for partial indices */
  int tnum;                /* DB Page containing root of this index */
  LogEst szIdxRow;         /* Estimated average row size in bytes */
  u16 nColumn;             /* Number of columns in table used by this index */
  u8 onError;              /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
  unsigned autoIndex:2;    /* 1==UNIQUE, 2==PRIMARY KEY, 0==CREATE INDEX */
  unsigned bUnordered:1;   /* Use this index for == or IN queries only */
  unsigned uniqNotNull:1;  /* True if UNIQUE and NOT NULL for all columns */
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
  int nSample;             /* Number of elements in aSample[] */
  int nSampleCol;          /* Size of IndexSample.anEq[] and so on */
  tRowcnt *aAvgEq;         /* Average nEq values for keys not in aSample */
  IndexSample *aSample;    /* Samples of the left-most key */
#endif
};

/*
** Each sample stored in the sqlite_stat3 table is represented in memory 
** using a structure of this type.  See documentation at the top of the
** analyze.c source file for additional information.
*/
struct IndexSample {
  void *p;          /* Pointer to sampled record */
  int n;            /* Size of record in bytes */





  tRowcnt *anEq;    /* Est. number of rows where the key equals this sample */
  tRowcnt *anLt;    /* Est. number of rows where key is less than this sample */
  tRowcnt *anDLt;   /* Est. number of distinct keys less than this sample */
};

/*
** Each token coming out of the lexer is an instance of
** this structure.  Tokens are also used as part of an expression.
**
** Note if Token.z==0 then Token.dyn and Token.n are undefined and
................................................................................
** are contained within the same memory allocation.  Note, however, that
** the subtrees in Expr.x.pList or Expr.x.pSelect are always separately
** allocated, regardless of whether or not EP_Reduced is set.
*/
struct Expr {
  u8 op;                 /* Operation performed by this node */
  char affinity;         /* The affinity of the column or 0 if not a column */
  u32 flags;             /* Various flags.  EP_* See below */
  union {
    char *zToken;          /* Token value. Zero terminated and dequoted */
    int iValue;            /* Non-negative integer value if EP_IntValue */
  } u;

  /* If the EP_TokenOnly flag is set in the Expr.flags mask, then no
  ** space is allocated for the fields below this point. An attempt to
  ** access them will result in a segfault or malfunction. 
  *********************************************************************/

  Expr *pLeft;           /* Left subnode */
  Expr *pRight;          /* Right subnode */
  union {
    ExprList *pList;     /* op = IN, EXISTS, SELECT, CASE, FUNCTION, BETWEEN */
    Select *pSelect;     /* EP_xIsSelect and op = IN, EXISTS, SELECT */
  } x;

  /* If the EP_Reduced flag is set in the Expr.flags mask, then no
  ** space is allocated for the fields below this point. An attempt to
  ** access them will result in a segfault or malfunction.
  *********************************************************************/

#if SQLITE_MAX_EXPR_DEPTH>0
  int nHeight;           /* Height of the tree headed by this node */
#endif
  int iTable;            /* TK_COLUMN: cursor number of table holding column
                         ** TK_REGISTER: register number
                         ** TK_TRIGGER: 1 -> new, 0 -> old
                         ** EP_Unlikely:  1000 times likelihood */
  ynVar iColumn;         /* TK_COLUMN: column index.  -1 for rowid.
                         ** TK_VARIABLE: variable number (always >= 1). */
  i16 iAgg;              /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
  i16 iRightJoinTable;   /* If EP_FromJoin, the right table of the join */

  u8 op2;                /* TK_REGISTER: original value of Expr.op
                         ** TK_COLUMN: the value of p5 for OP_Column
                         ** TK_AGG_FUNCTION: nesting depth */
  AggInfo *pAggInfo;     /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */
  Table *pTab;           /* Table for TK_COLUMN expressions. */
};

/*
** The following are the meanings of bits in the Expr.flags field.
*/
#define EP_FromJoin  0x000001 /* Originated in ON or USING clause of a join */
#define EP_Agg       0x000002 /* Contains one or more aggregate functions */
#define EP_Resolved  0x000004 /* IDs have been resolved to COLUMNs */
#define EP_Error     0x000008 /* Expression contains one or more errors */
#define EP_Distinct  0x000010 /* Aggregate function with DISTINCT keyword */
#define EP_VarSelect 0x000020 /* pSelect is correlated, not constant */
#define EP_DblQuoted 0x000040 /* token.z was originally in "..." */
#define EP_InfixFunc 0x000080 /* True for an infix function: LIKE, GLOB, etc */
#define EP_Collate   0x000100 /* Tree contains a TK_COLLATE opeartor */
#define EP_FixedDest 0x000200 /* Result needed in a specific register */
#define EP_IntValue  0x000400 /* Integer value contained in u.iValue */
#define EP_xIsSelect 0x000800 /* x.pSelect is valid (otherwise x.pList is) */
#define EP_Skip      0x001000 /* COLLATE, AS, or UNLIKELY */
#define EP_Reduced   0x002000 /* Expr struct EXPR_REDUCEDSIZE bytes only */
#define EP_TokenOnly 0x004000 /* Expr struct EXPR_TOKENONLYSIZE bytes only */
#define EP_Static    0x008000 /* Held in memory not obtained from malloc() */
#define EP_MemToken  0x010000 /* Need to sqlite3DbFree() Expr.zToken */
#define EP_NoReduce  0x020000 /* Cannot EXPRDUP_REDUCE this Expr */
#define EP_Unlikely  0x040000 /* unlikely() or likelihood() function */

/*
** These macros can be used to test, set, or clear bits in the 
** Expr.flags field.
*/
#define ExprHasProperty(E,P)     (((E)->flags&(P))!=0)
#define ExprHasAllProperty(E,P)  (((E)->flags&(P))==(P))
#define ExprSetProperty(E,P)     (E)->flags|=(P)
#define ExprClearProperty(E,P)   (E)->flags&=~(P)

/* The ExprSetVVAProperty() macro is used for Verification, Validation,
** and Accreditation only.  It works like ExprSetProperty() during VVA
** processes but is a no-op for delivery.
*/
#ifdef SQLITE_DEBUG
# define ExprSetVVAProperty(E,P)  (E)->flags|=(P)
#else
# define ExprSetVVAProperty(E,P)
#endif






/*
** Macros to determine the number of bytes required by a normal Expr 
** struct, an Expr struct with the EP_Reduced flag set in Expr.flags 
** and an Expr struct with the EP_TokenOnly flag set.
*/
#define EXPR_FULLSIZE           sizeof(Expr)           /* Full size */
................................................................................
** routines as they walk the parse tree to make database references
** explicit.  
*/
typedef struct DbFixer DbFixer;
struct DbFixer {
  Parse *pParse;      /* The parsing context.  Error messages written here */
  Schema *pSchema;    /* Fix items to this schema */
  int bVarOnly;       /* Check for variable references only */
  const char *zDb;    /* Make sure all objects are contained in this database */
  const char *zType;  /* Type of the container - used for error messages */
  const Token *pName; /* Name of the container - used for error messages */
};

/*
** An objected used to accumulate the text of a string where we
................................................................................
# define sqlite3AuthRead(a,b,c,d)
# define sqlite3AuthCheck(a,b,c,d,e)    SQLITE_OK
# define sqlite3AuthContextPush(a,b,c)
# define sqlite3AuthContextPop(a)  ((void)(a))
#endif
SQLITE_PRIVATE void sqlite3Attach(Parse*, Expr*, Expr*, Expr*);
SQLITE_PRIVATE void sqlite3Detach(Parse*, Expr*);
SQLITE_PRIVATE void sqlite3FixInit(DbFixer*, Parse*, int, const char*, const Token*);
SQLITE_PRIVATE int sqlite3FixSrcList(DbFixer*, SrcList*);
SQLITE_PRIVATE int sqlite3FixSelect(DbFixer*, Select*);
SQLITE_PRIVATE int sqlite3FixExpr(DbFixer*, Expr*);
SQLITE_PRIVATE int sqlite3FixExprList(DbFixer*, ExprList*);
SQLITE_PRIVATE int sqlite3FixTriggerStep(DbFixer*, TriggerStep*);
SQLITE_PRIVATE int sqlite3AtoF(const char *z, double*, int, u8);
SQLITE_PRIVATE int sqlite3GetInt32(const char *, int*);
SQLITE_PRIVATE int sqlite3Atoi(const char*);
SQLITE_PRIVATE int sqlite3Utf16ByteLen(const void *pData, int nChar);
SQLITE_PRIVATE int sqlite3Utf8CharLen(const char *pData, int nByte);
SQLITE_PRIVATE u32 sqlite3Utf8Read(const u8**);
SQLITE_PRIVATE LogEst sqlite3LogEst(u64);
SQLITE_PRIVATE LogEst sqlite3LogEstAdd(LogEst,LogEst);
#ifndef SQLITE_OMIT_VIRTUALTABLE
SQLITE_PRIVATE LogEst sqlite3LogEstFromDouble(double);
#endif
SQLITE_PRIVATE u64 sqlite3LogEstToInt(LogEst);

/*
** Routines to read and write variable-length integers.  These used to
** be defined locally, but now we use the varint routines in the util.c
** file.  Code should use the MACRO forms below, as the Varint32 versions
** are coded to assume the single byte case is already handled (which 
** the MACRO form does).
................................................................................
SQLITE_PRIVATE const void *sqlite3ValueText(sqlite3_value*, u8);
SQLITE_PRIVATE int sqlite3ValueBytes(sqlite3_value*, u8);
SQLITE_PRIVATE void sqlite3ValueSetStr(sqlite3_value*, int, const void *,u8, 
                        void(*)(void*));
SQLITE_PRIVATE void sqlite3ValueFree(sqlite3_value*);
SQLITE_PRIVATE sqlite3_value *sqlite3ValueNew(sqlite3 *);
SQLITE_PRIVATE char *sqlite3Utf16to8(sqlite3 *, const void*, int, u8);



SQLITE_PRIVATE int sqlite3ValueFromExpr(sqlite3 *, Expr *, u8, u8, sqlite3_value **);
SQLITE_PRIVATE void sqlite3ValueApplyAffinity(sqlite3_value *, u8, u8);
#ifndef SQLITE_AMALGAMATION
SQLITE_PRIVATE const unsigned char sqlite3OpcodeProperty[];
SQLITE_PRIVATE const unsigned char sqlite3UpperToLower[];
SQLITE_PRIVATE const unsigned char sqlite3CtypeMap[];
SQLITE_PRIVATE const Token sqlite3IntTokens[];
................................................................................
SQLITE_PRIVATE void sqlite3ResolveSelectNames(Parse*, Select*, NameContext*);
SQLITE_PRIVATE void sqlite3ResolveSelfReference(Parse*,Table*,int,Expr*,ExprList*);
SQLITE_PRIVATE int sqlite3ResolveOrderGroupBy(Parse*, Select*, ExprList*, const char*);
SQLITE_PRIVATE void sqlite3ColumnDefault(Vdbe *, Table *, int, int);
SQLITE_PRIVATE void sqlite3AlterFinishAddColumn(Parse *, Token *);
SQLITE_PRIVATE void sqlite3AlterBeginAddColumn(Parse *, SrcList *);
SQLITE_PRIVATE CollSeq *sqlite3GetCollSeq(Parse*, u8, CollSeq *, const char*);
SQLITE_PRIVATE char sqlite3AffinityType(const char*, u8*);
SQLITE_PRIVATE void sqlite3Analyze(Parse*, Token*, Token*);
SQLITE_PRIVATE int sqlite3InvokeBusyHandler(BusyHandler*);
SQLITE_PRIVATE int sqlite3FindDb(sqlite3*, Token*);
SQLITE_PRIVATE int sqlite3FindDbName(sqlite3 *, const char *);
SQLITE_PRIVATE int sqlite3AnalysisLoad(sqlite3*,int iDB);
SQLITE_PRIVATE void sqlite3DeleteIndexSamples(sqlite3*,Index*);
SQLITE_PRIVATE void sqlite3DefaultRowEst(Index*);
................................................................................
SQLITE_PRIVATE char *sqlite3StrAccumFinish(StrAccum*);
SQLITE_PRIVATE void sqlite3StrAccumReset(StrAccum*);
SQLITE_PRIVATE void sqlite3SelectDestInit(SelectDest*,int,int);
SQLITE_PRIVATE Expr *sqlite3CreateColumnExpr(sqlite3 *, SrcList *, int, int);

SQLITE_PRIVATE void sqlite3BackupRestart(sqlite3_backup *);
SQLITE_PRIVATE void sqlite3BackupUpdate(sqlite3_backup *, Pgno, const u8 *);

#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
SQLITE_PRIVATE void sqlite3AnalyzeFunctions(void);
SQLITE_PRIVATE int sqlite3Stat4ProbeSetValue(Parse*,Index*,UnpackedRecord**,Expr*,u8,int,int*);
SQLITE_PRIVATE void sqlite3Stat4ProbeFree(UnpackedRecord*);
#endif

/*
** The interface to the LEMON-generated parser
*/
SQLITE_PRIVATE void *sqlite3ParserAlloc(void*(*)(size_t));
SQLITE_PRIVATE void sqlite3ParserFree(void*, void(*)(void*));
SQLITE_PRIVATE void sqlite3Parser(void*, int, Token, Parse*);
................................................................................
SQLITE_PRIVATE void sqlite3VtabArgExtend(Parse*, Token*);
SQLITE_PRIVATE int sqlite3VtabCallCreate(sqlite3*, int, const char *, char **);
SQLITE_PRIVATE int sqlite3VtabCallConnect(Parse*, Table*);
SQLITE_PRIVATE int sqlite3VtabCallDestroy(sqlite3*, int, const char *);
SQLITE_PRIVATE int sqlite3VtabBegin(sqlite3 *, VTable *);
SQLITE_PRIVATE FuncDef *sqlite3VtabOverloadFunction(sqlite3 *,FuncDef*, int nArg, Expr*);
SQLITE_PRIVATE void sqlite3InvalidFunction(sqlite3_context*,int,sqlite3_value**);
SQLITE_PRIVATE sqlite3_int64 sqlite3StmtCurrentTime(sqlite3_context*);
SQLITE_PRIVATE int sqlite3VdbeParameterIndex(Vdbe*, const char*, int);
SQLITE_PRIVATE int sqlite3TransferBindings(sqlite3_stmt *, sqlite3_stmt *);
SQLITE_PRIVATE int sqlite3Reprepare(Vdbe*);
SQLITE_PRIVATE void sqlite3ExprListCheckLength(Parse*, ExprList*, const char*);
SQLITE_PRIVATE CollSeq *sqlite3BinaryCompareCollSeq(Parse *, Expr *, Expr *);
SQLITE_PRIVATE int sqlite3TempInMemory(const sqlite3*);
SQLITE_PRIVATE const char *sqlite3JournalModename(int);
................................................................................
** no-op macros if OMIT_FOREIGN_KEY is defined. In this case no foreign
** key functionality is available. If OMIT_TRIGGER is defined but
** OMIT_FOREIGN_KEY is not, only some of the functions are no-oped. In
** this case foreign keys are parsed, but no other functionality is 
** provided (enforcement of FK constraints requires the triggers sub-system).
*/
#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
SQLITE_PRIVATE   void sqlite3FkCheck(Parse*, Table*, int, int, int*, int);
SQLITE_PRIVATE   void sqlite3FkDropTable(Parse*, SrcList *, Table*);
SQLITE_PRIVATE   void sqlite3FkActions(Parse*, Table*, ExprList*, int, int*, int);
SQLITE_PRIVATE   int sqlite3FkRequired(Parse*, Table*, int*, int);
SQLITE_PRIVATE   u32 sqlite3FkOldmask(Parse*, Table*);
SQLITE_PRIVATE   FKey *sqlite3FkReferences(Table *);
#else
  #define sqlite3FkActions(a,b,c,d,e,f)
  #define sqlite3FkCheck(a,b,c,d)
  #define sqlite3FkDropTable(a,b,c)
  #define sqlite3FkOldmask(a,b)          0
  #define sqlite3FkRequired(a,b,c,d,e,f) 0
#endif
#ifndef SQLITE_OMIT_FOREIGN_KEY
SQLITE_PRIVATE   void sqlite3FkDelete(sqlite3 *, Table*);
SQLITE_PRIVATE   int sqlite3FkLocateIndex(Parse*,Table*,FKey*,Index**,int**);
#else
  #define sqlite3FkDelete(a,b)
  #define sqlite3FkLocateIndex(a,b,c,d,e)
................................................................................
#endif
#ifdef SQLITE_ENABLE_OVERSIZE_CELL_CHECK
  "ENABLE_OVERSIZE_CELL_CHECK",
#endif
#ifdef SQLITE_ENABLE_RTREE
  "ENABLE_RTREE",
#endif
#if defined(SQLITE_ENABLE_STAT4)
  "ENABLE_STAT4",
#elif defined(SQLITE_ENABLE_STAT3)
  "ENABLE_STAT3",
#endif
#ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
  "ENABLE_UNLOCK_NOTIFY",
#endif
#ifdef SQLITE_ENABLE_UPDATE_DELETE_LIMIT
  "ENABLE_UPDATE_DELETE_LIMIT",
................................................................................
  yDbMask btreeMask;      /* Bitmask of db->aDb[] entries referenced */
  yDbMask lockMask;       /* Subset of btreeMask that requires a lock */
  int iStatement;         /* Statement number (or 0 if has not opened stmt) */
  u32 aCounter[5];        /* Counters used by sqlite3_stmt_status() */
#ifndef SQLITE_OMIT_TRACE
  i64 startTime;          /* Time when query started - used for profiling */
#endif
  i64 iCurrentTime;       /* Value of julianday('now') for this statement */
  i64 nFkConstraint;      /* Number of imm. FK constraints this VM */
  i64 nStmtDefCons;       /* Number of def. constraints when stmt started */
  i64 nStmtDefImmCons;    /* Number of def. imm constraints when stmt started */
  char *zSql;             /* Text of the SQL statement that generated this */
  void *pFree;            /* Free this when deleting the vdbe */
#ifdef SQLITE_DEBUG
  FILE *trace;            /* Write an execution trace here, if not NULL */
................................................................................

/*
** Set the time to the current time reported by the VFS.
**
** Return the number of errors.
*/
static int setDateTimeToCurrent(sqlite3_context *context, DateTime *p){
  p->iJD = sqlite3StmtCurrentTime(context);
  if( p->iJD>0 ){
    p->validJD = 1;
    return 0;
  }else{
    return 1;
  }
}

................................................................................
** The following routine implements the rough equivalent of localtime_r()
** using whatever operating-system specific localtime facility that
** is available.  This routine returns 0 on success and
** non-zero on any kind of error.
**
** If the sqlite3GlobalConfig.bLocaltimeFault variable is true then this
** routine will always fail.
**
** EVIDENCE-OF: R-62172-00036 In this implementation, the standard C
** library function localtime_r() is used to assist in the calculation of
** local time.
*/
static int osLocaltime(time_t *t, struct tm *pTm){
  int rc;
#if (!defined(HAVE_LOCALTIME_R) || !HAVE_LOCALTIME_R) \
      && (!defined(HAVE_LOCALTIME_S) || !HAVE_LOCALTIME_S)
  struct tm *pX;
#if SQLITE_THREADSAFE>0
................................................................................

  /* Initialize the contents of sLocal to avoid a compiler warning. */
  memset(&sLocal, 0, sizeof(sLocal));

  x = *p;
  computeYMD_HMS(&x);
  if( x.Y<1971 || x.Y>=2038 ){
    /* EVIDENCE-OF: R-55269-29598 The localtime_r() C function normally only
    ** works for years between 1970 and 2037. For dates outside this range,
    ** SQLite attempts to map the year into an equivalent year within this
    ** range, do the calculation, then map the year back.
    */
    x.Y = 2000;
    x.M = 1;
    x.D = 1;
    x.h = 0;
    x.m = 0;
    x.s = 0.0;
  } else {
................................................................................
  struct tm *pTm;
  struct tm sNow;
  char zBuf[20];

  UNUSED_PARAMETER(argc);
  UNUSED_PARAMETER(argv);

  iT = sqlite3StmtCurrentTime(context);
  if( iT<=0 ) return;
  t = iT/1000 - 10000*(sqlite3_int64)21086676;
#ifdef HAVE_GMTIME_R
  pTm = gmtime_r(&t, &sNow);
#else
  sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
  pTm = gmtime(&t);
  if( pTm ) memcpy(&sNow, pTm, sizeof(sNow));
................................................................................
*/
static int sqlite3MemSize(void *p){
  struct MemBlockHdr *pHdr;
  if( !p ){
    return 0;
  }
  pHdr = sqlite3MemsysGetHeader(p);
  return (int)pHdr->iSize;
}

/*
** Initialize the memory allocation subsystem.
*/
static int sqlite3MemInit(void *NotUsed){
  UNUSED_PARAMETER(NotUsed);
................................................................................
** to clear the content of a freed allocation to unpredictable values.
*/
static void randomFill(char *pBuf, int nByte){
  unsigned int x, y, r;
  x = SQLITE_PTR_TO_INT(pBuf);
  y = nByte | 1;
  while( nByte >= 4 ){
    x = (x>>1) ^ (-(int)(x&1) & 0xd0000001);
    y = y*1103515245 + 12345;
    r = x ^ y;
    *(int*)pBuf = r;
    pBuf += 4;
    nByte -= 4;
  }
  while( nByte-- > 0 ){
    x = (x>>1) ^ (-(int)(x&1) & 0xd0000001);
    y = y*1103515245 + 12345;
    r = x ^ y;
    *(pBuf++) = r & 0xff;
  }
}

/*
................................................................................
    pHdr->pNext->pPrev = pHdr->pPrev;
  }else{
    assert( mem.pLast==pHdr );
    mem.pLast = pHdr->pPrev;
  }
  z = (char*)pBt;
  z -= pHdr->nTitle;
  adjustStats((int)pHdr->iSize, -1);
  randomFill(z, sizeof(void*)*pHdr->nBacktraceSlots + sizeof(*pHdr) +
                (int)pHdr->iSize + sizeof(int) + pHdr->nTitle);
  free(z);
  sqlite3_mutex_leave(mem.mutex);  
}

/*
** Change the size of an existing memory allocation.
**
................................................................................
  struct MemBlockHdr *pOldHdr;
  void *pNew;
  assert( mem.disallow==0 );
  assert( (nByte & 7)==0 );     /* EV: R-46199-30249 */
  pOldHdr = sqlite3MemsysGetHeader(pPrior);
  pNew = sqlite3MemMalloc(nByte);
  if( pNew ){
    memcpy(pNew, pPrior, (int)(nByte<pOldHdr->iSize ? nByte : pOldHdr->iSize));
    if( nByte>pOldHdr->iSize ){
      randomFill(&((char*)pNew)[pOldHdr->iSize], nByte - (int)pOldHdr->iSize);
    }
    sqlite3MemFree(pPrior);
  }
  return pNew;
}

/*
................................................................................
}

SQLITE_PRIVATE void sqlite3MemdebugSync(){
  struct MemBlockHdr *pHdr;
  for(pHdr=mem.pFirst; pHdr; pHdr=pHdr->pNext){
    void **pBt = (void**)pHdr;
    pBt -= pHdr->nBacktraceSlots;
    mem.xBacktrace((int)pHdr->iSize, pHdr->nBacktrace-1, &pBt[1]);
  }
}

/*
** Open the file indicated and write a log of all unfreed memory 
** allocations into that log.
*/
................................................................................
      OSVERSIONINFO sInfo;
      sInfo.dwOSVersionInfoSize = sizeof(sInfo);
      GetVersionEx(&sInfo);
      osType = sInfo.dwPlatformId==VER_PLATFORM_WIN32_NT ? 2 : 1;
    }
    return osType==2;
  }
#endif /* SQLITE_OS_WINCE || SQLITE_OS_WINRT */
#endif

#ifdef SQLITE_DEBUG
/*
** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routine are
** intended for use only inside assert() statements.
*/
................................................................................
};
static int winMutex_isInit = 0;
/* As winMutexInit() and winMutexEnd() are called as part
** of the sqlite3_initialize and sqlite3_shutdown()
** processing, the "interlocked" magic is probably not
** strictly necessary.
*/
static LONG winMutex_lock = 0;

SQLITE_API void sqlite3_win32_sleep(DWORD milliseconds); /* os_win.c */

static int winMutexInit(void){ 
  /* The first to increment to 1 does actual initialization */
  if( InterlockedCompareExchange(&winMutex_lock, 1, 0)==0 ){
    int i;
................................................................................

/*
** Free memory that might be associated with a particular database
** connection.
*/
SQLITE_PRIVATE void sqlite3DbFree(sqlite3 *db, void *p){
  assert( db==0 || sqlite3_mutex_held(db->mutex) );
  if( p==0 ) return;
  if( db ){
    if( db->pnBytesFreed ){
      *db->pnBytesFreed += sqlite3DbMallocSize(db, p);
      return;
    }
    if( isLookaside(db, p) ){
      LookasideSlot *pBuf = (LookasideSlot*)p;
................................................................................
  assert( (m.flags & MEM_Term)!=0 || db->mallocFailed );
  assert( (m.flags & MEM_Str)!=0 || db->mallocFailed );
  assert( (m.flags & MEM_Dyn)!=0 || db->mallocFailed );
  assert( m.z || db->mallocFailed );
  return m.z;
}



























/*
** zIn is a UTF-16 encoded unicode string at least nChar characters long.
** Return the number of bytes in the first nChar unicode characters
** in pZ.  nChar must be non-negative.
*/
SQLITE_PRIVATE int sqlite3Utf16ByteLen(const void *zIn, int nChar){
  int c;
................................................................................
  switch( quote ){
    case '\'':  break;
    case '"':   break;
    case '`':   break;                /* For MySQL compatibility */
    case '[':   quote = ']';  break;  /* For MS SqlServer compatibility */
    default:    return -1;
  }
  for(i=1, j=0;; i++){
    assert( z[i] );
    if( z[i]==quote ){
      if( z[i+1]==quote ){
        z[j++] = quote;
        i++;
      }else{
        break;
      }
................................................................................
    int i, sz;
    sz = sqlite3Strlen30(z);
    for(i=sz-1; i>0 && z[i]!='/' && z[i]!='.'; i--){}
    if( z[i]=='.' && ALWAYS(sz>i+4) ) memmove(&z[i+1], &z[sz-3], 4);
  }
}
#endif

/* 
** Find (an approximate) sum of two LogEst values.  This computation is
** not a simple "+" operator because LogEst is stored as a logarithmic
** value.
** 
*/
SQLITE_PRIVATE LogEst sqlite3LogEstAdd(LogEst a, LogEst b){
  static const unsigned char x[] = {
     10, 10,                         /* 0,1 */
      9, 9,                          /* 2,3 */
      8, 8,                          /* 4,5 */
      7, 7, 7,                       /* 6,7,8 */
      6, 6, 6,                       /* 9,10,11 */
      5, 5, 5,                       /* 12-14 */
      4, 4, 4, 4,                    /* 15-18 */
      3, 3, 3, 3, 3, 3,              /* 19-24 */
      2, 2, 2, 2, 2, 2, 2,           /* 25-31 */
  };
  if( a>=b ){
    if( a>b+49 ) return a;
    if( a>b+31 ) return a+1;
    return a+x[a-b];
  }else{
    if( b>a+49 ) return b;
    if( b>a+31 ) return b+1;
    return b+x[b-a];
  }
}

/*
** Convert an integer into a LogEst.  In other words, compute a
** good approximatation for 10*log2(x).
*/
SQLITE_PRIVATE LogEst sqlite3LogEst(u64 x){
  static LogEst a[] = { 0, 2, 3, 5, 6, 7, 8, 9 };
  LogEst y = 40;
  if( x<8 ){
    if( x<2 ) return 0;
    while( x<8 ){  y -= 10; x <<= 1; }
  }else{
    while( x>255 ){ y += 40; x >>= 4; }
    while( x>15 ){  y += 10; x >>= 1; }
  }
  return a[x&7] + y - 10;
}

#ifndef SQLITE_OMIT_VIRTUALTABLE
/*
** Convert a double into a LogEst
** In other words, compute an approximation for 10*log2(x).
*/
SQLITE_PRIVATE LogEst sqlite3LogEstFromDouble(double x){
  u64 a;
  LogEst e;
  assert( sizeof(x)==8 && sizeof(a)==8 );
  if( x<=1 ) return 0;
  if( x<=2000000000 ) return sqlite3LogEst((u64)x);
  memcpy(&a, &x, 8);
  e = (a>>52) - 1022;
  return e*10;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */

/*
** Convert a LogEst into an integer.
*/
SQLITE_PRIVATE u64 sqlite3LogEstToInt(LogEst x){
  u64 n;
  if( x<10 ) return 1;
  n = x%10;
  x /= 10;
  if( n>=5 ) n -= 2;
  else if( n>=1 ) n -= 1;
  if( x>=3 ) return (n+8)<<(x-3);
  return (n+8)>>(3-x);
}

/************** End of util.c ************************************************/
/************** Begin file hash.c ********************************************/
/*
** 2001 September 22
**
** The author disclaims copyright to this source code.  In place of
................................................................................
  unsigned short int ctrlFlags;       /* Behavioral bits.  UNIXFILE_* flags */
  int lastErrno;                      /* The unix errno from last I/O error */
  void *lockingContext;               /* Locking style specific state */
  UnixUnusedFd *pUnused;              /* Pre-allocated UnixUnusedFd */
  const char *zPath;                  /* Name of the file */
  unixShm *pShm;                      /* Shared memory segment information */
  int szChunk;                        /* Configured by FCNTL_CHUNK_SIZE */
#if SQLITE_MAX_MMAP_SIZE>0
  int nFetchOut;                      /* Number of outstanding xFetch refs */
  sqlite3_int64 mmapSize;             /* Usable size of mapping at pMapRegion */
  sqlite3_int64 mmapSizeActual;       /* Actual size of mapping at pMapRegion */
  sqlite3_int64 mmapSizeMax;          /* Configured FCNTL_MMAP_SIZE value */
  void *pMapRegion;                   /* Memory mapped region */
#endif
#ifdef __QNXNTO__
  int sectorSize;                     /* Device sector size */
  int deviceCharacteristics;          /* Precomputed device characteristics */
#endif
#if SQLITE_ENABLE_LOCKING_STYLE
  int openFlags;                      /* The flags specified at open() */
#endif
................................................................................

  { "rmdir",        (sqlite3_syscall_ptr)rmdir,           0 },
#define osRmdir     ((int(*)(const char*))aSyscall[19].pCurrent)

  { "fchown",       (sqlite3_syscall_ptr)posixFchown,     0 },
#define osFchown    ((int(*)(int,uid_t,gid_t))aSyscall[20].pCurrent)

#if !defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0
  { "mmap",       (sqlite3_syscall_ptr)mmap,     0 },
#define osMmap ((void*(*)(void*,size_t,int,int,int,off_t))aSyscall[21].pCurrent)

  { "munmap",       (sqlite3_syscall_ptr)munmap,          0 },
#define osMunmap ((void*(*)(void*,size_t))aSyscall[22].pCurrent)

#if HAVE_MREMAP
  { "mremap",       (sqlite3_syscall_ptr)mremap,          0 },
#else
  { "mremap",       (sqlite3_syscall_ptr)0,               0 },
#endif
#define osMremap ((void*(*)(void*,size_t,size_t,int,...))aSyscall[23].pCurrent)
#endif

}; /* End of the overrideable system calls */

/*
** This is the xSetSystemCall() method of sqlite3_vfs for all of the
** "unix" VFSes.  Return SQLITE_OK opon successfully updating the
** system call pointer, or SQLITE_NOTFOUND if there is no configurable
................................................................................
  }
  for(i++; i<ArraySize(aSyscall); i++){
    if( aSyscall[i].pCurrent!=0 ) return aSyscall[i].zName;
  }
  return 0;
}

/*
** Do not accept any file descriptor less than this value, in order to avoid
** opening database file using file descriptors that are commonly used for 
** standard input, output, and error.
*/
#ifndef SQLITE_MINIMUM_FILE_DESCRIPTOR
# define SQLITE_MINIMUM_FILE_DESCRIPTOR 3
#endif

/*
** Invoke open().  Do so multiple times, until it either succeeds or
** fails for some reason other than EINTR.
**
** If the file creation mode "m" is 0 then set it to the default for
** SQLite.  The default is SQLITE_DEFAULT_FILE_PERMISSIONS (normally
** 0644) as modified by the system umask.  If m is not 0, then
................................................................................
** transaction crashes and leaves behind hot journals, then any
** process that is able to write to the database will also be able to
** recover the hot journals.
*/
static int robust_open(const char *z, int f, mode_t m){
  int fd;
  mode_t m2 = m ? m : SQLITE_DEFAULT_FILE_PERMISSIONS;
  while(1){
#if defined(O_CLOEXEC)
    fd = osOpen(z,f|O_CLOEXEC,m2);
#else
    fd = osOpen(z,f,m2);
#endif
    if( fd<0 ){
      if( errno==EINTR ) continue;
      break;
    }
    if( fd>=SQLITE_MINIMUM_FILE_DESCRIPTOR ) break;
    osClose(fd);
    sqlite3_log(SQLITE_WARNING, 
                "attempt to open \"%s\" as file descriptor %d", z, fd);
    fd = -1;
    if( osOpen("/dev/null", f, m)<0 ) break;
  }
  if( fd>=0 ){
    if( m!=0 ){
      struct stat statbuf;
      if( osFstat(fd, &statbuf)==0 
       && statbuf.st_size==0
       && (statbuf.st_mode&0777)!=m 
      ){
................................................................................
** the requested locking level, this routine is a no-op.
*/
static int unixUnlock(sqlite3_file *id, int eFileLock){
  assert( eFileLock==SHARED_LOCK || ((unixFile *)id)->nFetchOut==0 );
  return posixUnlock(id, eFileLock, 0);
}

#if SQLITE_MAX_MMAP_SIZE>0
static int unixMapfile(unixFile *pFd, i64 nByte);
static void unixUnmapfile(unixFile *pFd);
#endif

/*
** This function performs the parts of the "close file" operation 
** common to all locking schemes. It closes the directory and file
** handles, if they are valid, and sets all fields of the unixFile
** structure to 0.
**
** It is *not* necessary to hold the mutex when this routine is called,
** even on VxWorks.  A mutex will be acquired on VxWorks by the
** vxworksReleaseFileId() routine.
*/
static int closeUnixFile(sqlite3_file *id){
  unixFile *pFile = (unixFile*)id;
#if SQLITE_MAX_MMAP_SIZE>0
  unixUnmapfile(pFile);
#endif
  if( pFile->h>=0 ){
    robust_close(pFile, pFile->h, __LINE__);
    pFile->h = -1;
  }
#if OS_VXWORKS
  if( pFile->pId ){
    if( pFile->ctrlFlags & UNIXFILE_DELETE ){
................................................................................
  int got;
  int prior = 0;
#if (!defined(USE_PREAD) && !defined(USE_PREAD64))
  i64 newOffset;
#endif
  TIMER_START;
  assert( cnt==(cnt&0x1ffff) );
  assert( id->h>2 );
  cnt &= 0x1ffff;
  do{
#if defined(USE_PREAD)
    got = osPread(id->h, pBuf, cnt, offset);
    SimulateIOError( got = -1 );
#elif defined(USE_PREAD64)
    got = osPread64(id->h, pBuf, cnt, offset);
................................................................................
  const void *pBuf,               /* Copy data from this buffer to the file */
  int nBuf,                       /* Size of buffer pBuf in bytes */
  int *piErrno                    /* OUT: Error number if error occurs */
){
  int rc = 0;                     /* Value returned by system call */

  assert( nBuf==(nBuf&0x1ffff) );
  assert( fd>2 );
  nBuf &= 0x1ffff;
  TIMER_START;

#if defined(USE_PREAD)
  do{ rc = osPwrite(fd, pBuf, nBuf, iOff); }while( rc<0 && errno==EINTR );
#elif defined(USE_PREAD64)
  do{ rc = osPwrite64(fd, pBuf, nBuf, iOff);}while( rc<0 && errno==EINTR);
................................................................................
    ** source.
    */
    if( pFile->inNormalWrite && nByte==0 ){
      pFile->transCntrChng = 1;
    }
#endif

#if SQLITE_MAX_MMAP_SIZE>0
    /* If the file was just truncated to a size smaller than the currently
    ** mapped region, reduce the effective mapping size as well. SQLite will
    ** use read() and write() to access data beyond this point from now on.  
    */
    if( nByte<pFile->mmapSize ){
      pFile->mmapSize = nByte;
    }
#endif

    return SQLITE_OK;
  }
}

/*
** Determine the current size of a file in bytes
................................................................................
        if( nWrite!=1 ) return SQLITE_IOERR_WRITE;
        iWrite += nBlk;
      }
#endif
    }
  }

#if SQLITE_MAX_MMAP_SIZE>0
  if( pFile->mmapSizeMax>0 && nByte>pFile->mmapSize ){
    int rc;
    if( pFile->szChunk<=0 ){
      if( robust_ftruncate(pFile->h, nByte) ){
        pFile->lastErrno = errno;
        return unixLogError(SQLITE_IOERR_TRUNCATE, "ftruncate", pFile->zPath);
      }
    }

    rc = unixMapfile(pFile, nByte);
    return rc;
  }
#endif

  return SQLITE_OK;
}

/*
** If *pArg is inititially negative then this is a query.  Set *pArg to
** 1 or 0 depending on whether or not bit mask of pFile->ctrlFlags is set.
................................................................................
      char *zTFile = sqlite3_malloc( pFile->pVfs->mxPathname );
      if( zTFile ){
        unixGetTempname(pFile->pVfs->mxPathname, zTFile);
        *(char**)pArg = zTFile;
      }
      return SQLITE_OK;
    }
#if SQLITE_MAX_MMAP_SIZE>0
    case SQLITE_FCNTL_MMAP_SIZE: {
      i64 newLimit = *(i64*)pArg;
      int rc = SQLITE_OK;
      if( newLimit>sqlite3GlobalConfig.mxMmap ){
        newLimit = sqlite3GlobalConfig.mxMmap;
      }
      *(i64*)pArg = pFile->mmapSizeMax;
................................................................................
        if( pFile->mmapSize>0 ){
          unixUnmapfile(pFile);
          rc = unixMapfile(pFile, -1);
        }
      }
      return rc;
    }
#endif
#ifdef SQLITE_DEBUG
    /* The pager calls this method to signal that it has done
    ** a rollback and that the database is therefore unchanged and
    ** it hence it is OK for the transaction change counter to be
    ** unchanged.
    */
    case SQLITE_FCNTL_DB_UNCHANGED: {
................................................................................
#else
# define unixShmMap     0
# define unixShmLock    0
# define unixShmBarrier 0
# define unixShmUnmap   0
#endif /* #ifndef SQLITE_OMIT_WAL */

#if SQLITE_MAX_MMAP_SIZE>0
/*
** If it is currently memory mapped, unmap file pFd.
*/
static void unixUnmapfile(unixFile *pFd){
  assert( pFd->nFetchOut==0 );

  if( pFd->pMapRegion ){
    osMunmap(pFd->pMapRegion, pFd->mmapSizeActual);
    pFd->pMapRegion = 0;
    pFd->mmapSize = 0;
    pFd->mmapSizeActual = 0;
  }

}


/*
** Return the system page size.
*/
static int unixGetPagesize(void){
#if HAVE_MREMAP
  return 512;
#elif defined(_BSD_SOURCE)
  return getpagesize();
#else
  return (int)sysconf(_SC_PAGESIZE);
#endif
}



/*
** Attempt to set the size of the memory mapping maintained by file 
** descriptor pFd to nNew bytes. Any existing mapping is discarded.
**
** If successful, this function sets the following variables:
**
**       unixFile.pMapRegion
................................................................................
    ** will probably fail too. Fall back to using xRead/xWrite exclusively
    ** in this case.  */
    pFd->mmapSizeMax = 0;
  }
  pFd->pMapRegion = (void *)pNew;
  pFd->mmapSize = pFd->mmapSizeActual = nNew;
}


/*
** Memory map or remap the file opened by file-descriptor pFd (if the file
** is already mapped, the existing mapping is replaced by the new). Or, if 
** there already exists a mapping for this file, and there are still 
** outstanding xFetch() references to it, this function is a no-op.
**
................................................................................
** using SQLITE_FCNTL_MMAP_LIMIT, whichever is smaller.
**
** SQLITE_OK is returned if no error occurs (even if the mapping is not
** recreated as a result of outstanding references) or an SQLite error
** code otherwise.
*/
static int unixMapfile(unixFile *pFd, i64 nByte){

  i64 nMap = nByte;
  int rc;

  assert( nMap>=0 || pFd->nFetchOut==0 );
  if( pFd->nFetchOut>0 ) return SQLITE_OK;

  if( nMap<0 ){
................................................................................
  if( nMap!=pFd->mmapSize ){
    if( nMap>0 ){
      unixRemapfile(pFd, nMap);
    }else{
      unixUnmapfile(pFd);
    }
  }


  return SQLITE_OK;
}
#endif /* SQLITE_MAX_MMAP_SIZE>0 */

/*
** If possible, return a pointer to a mapping of file fd starting at offset
** iOff. The mapping must be valid for at least nAmt bytes.
**
** If such a pointer can be obtained, store it in *pp and return SQLITE_OK.
** Or, if one cannot but no error occurs, set *pp to 0 and return SQLITE_OK.
................................................................................
** to inform the VFS layer that, according to POSIX, any existing mapping 
** may now be invalid and should be unmapped.
*/
static int unixUnfetch(sqlite3_file *fd, i64 iOff, void *p){
  unixFile *pFd = (unixFile *)fd;   /* The underlying database file */
  UNUSED_PARAMETER(iOff);

#if SQLITE_MAX_MMAP_SIZE>0
  /* If p==0 (unmap the entire file) then there must be no outstanding 
  ** xFetch references. Or, if p!=0 (meaning it is an xFetch reference),
  ** then there must be at least one outstanding.  */
  assert( (p==0)==(pFd->nFetchOut==0) );

  /* If p!=0, it must match the iOff value. */
  assert( p==0 || p==&((u8 *)pFd->pMapRegion)[iOff] );
................................................................................
  if( p ){
    pFd->nFetchOut--;
  }else{
    unixUnmapfile(pFd);
  }

  assert( pFd->nFetchOut>=0 );
#endif
  return SQLITE_OK;
}

/*
** Here ends the implementation of all sqlite3_file methods.
**
********************** End sqlite3_file Methods *******************************
................................................................................
  assert( zFilename!=0 || (ctrlFlags & UNIXFILE_NOLOCK)!=0 );

  OSTRACE(("OPEN    %-3d %s\n", h, zFilename));
  pNew->h = h;
  pNew->pVfs = pVfs;
  pNew->zPath = zFilename;
  pNew->ctrlFlags = (u8)ctrlFlags;
#if SQLITE_MAX_MMAP_SIZE>0
  pNew->mmapSizeMax = sqlite3GlobalConfig.szMmap;
#endif
  if( sqlite3_uri_boolean(((ctrlFlags & UNIXFILE_URI) ? zFilename : 0),
                           "psow", SQLITE_POWERSAFE_OVERWRITE) ){
    pNew->ctrlFlags |= UNIXFILE_PSOW;
  }
  if( strcmp(pVfs->zName,"unix-excl")==0 ){
    pNew->ctrlFlags |= UNIXFILE_EXCL;
  }
................................................................................
/*
** Return the name of a directory in which to put temporary files.
** If no suitable temporary file directory can be found, return NULL.
*/
static const char *unixTempFileDir(void){
  static const char *azDirs[] = {
     0,
     0,
     0,
     "/var/tmp",
     "/usr/tmp",
     "/tmp",
     0        /* List terminator */
  };
  unsigned int i;
  struct stat buf;
  const char *zDir = 0;

  azDirs[0] = sqlite3_temp_directory;
  if( !azDirs[1] ) azDirs[1] = getenv("SQLITE_TMPDIR");
  if( !azDirs[2] ) azDirs[2] = getenv("TMPDIR");
  for(i=0; i<sizeof(azDirs)/sizeof(azDirs[0]); zDir=azDirs[i++]){
    if( zDir==0 ) continue;
    if( osStat(zDir, &buf) ) continue;
    if( !S_ISDIR(buf.st_mode) ) continue;
    if( osAccess(zDir, 07) ) continue;
    break;
  }
................................................................................
**
** This file contains code that is specific to Windows.
*/
#if SQLITE_OS_WIN               /* This file is used for Windows only */

#ifdef __CYGWIN__
# include <sys/cygwin.h>
# include <errno.h> /* amalgamator: keep */
#endif

/*
** Include code that is common to all os_*.c files
*/
/************** Include os_common.h in the middle of os_win.c ****************/
/************** Begin file os_common.h ***************************************/
................................................................................
/************** Continuing where we left off in os_win.c *********************/

/*
** Compiling and using WAL mode requires several APIs that are only
** available in Windows platforms based on the NT kernel.
*/
#if !SQLITE_OS_WINNT && !defined(SQLITE_OMIT_WAL)
#  error "WAL mode requires support from the Windows NT kernel, compile\
 with SQLITE_OMIT_WAL."
#endif

/*
** Are most of the Win32 ANSI APIs available (i.e. with certain exceptions
** based on the sub-platform)?
*/
#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && !defined(SQLITE_WIN32_NO_ANSI)
#  define SQLITE_WIN32_HAS_ANSI
#endif

/*
** Are most of the Win32 Unicode APIs available (i.e. with certain exceptions
** based on the sub-platform)?
*/
#if (SQLITE_OS_WINCE || SQLITE_OS_WINNT || SQLITE_OS_WINRT) && \
    !defined(SQLITE_WIN32_NO_WIDE)
#  define SQLITE_WIN32_HAS_WIDE
#endif

/*
** Make sure at least one set of Win32 APIs is available.
*/
#if !defined(SQLITE_WIN32_HAS_ANSI) && !defined(SQLITE_WIN32_HAS_WIDE)
#  error "At least one of SQLITE_WIN32_HAS_ANSI and SQLITE_WIN32_HAS_WIDE\
 must be defined."
#endif

/*
** Maximum pathname length (in chars) for Win32.  This should normally be
** MAX_PATH.
*/
#ifndef SQLITE_WIN32_MAX_PATH_CHARS
#  define SQLITE_WIN32_MAX_PATH_CHARS   (MAX_PATH)
#endif

/*
** Maximum pathname length (in chars) for WinNT.  This should normally be
** 32767.
*/
#ifndef SQLITE_WINNT_MAX_PATH_CHARS
#  define SQLITE_WINNT_MAX_PATH_CHARS   (32767)
#endif

/*
** Maximum pathname length (in bytes) for Win32.  The MAX_PATH macro is in
** characters, so we allocate 3 bytes per character assuming worst-case of
** 4-bytes-per-character for UTF8.
*/
#ifndef SQLITE_WIN32_MAX_PATH_BYTES
#  define SQLITE_WIN32_MAX_PATH_BYTES   (SQLITE_WIN32_MAX_PATH_CHARS*4)
#endif

/*
** Maximum pathname length (in bytes) for WinNT.  This should normally be
** 32767 * sizeof(WCHAR).
*/
#ifndef SQLITE_WINNT_MAX_PATH_BYTES
#  define SQLITE_WINNT_MAX_PATH_BYTES   \
                            (sizeof(WCHAR) * SQLITE_WINNT_MAX_PATH_CHARS)
#endif

/*
** Maximum error message length (in chars) for WinRT.
*/
#ifndef SQLITE_WIN32_MAX_ERRMSG_CHARS
#  define SQLITE_WIN32_MAX_ERRMSG_CHARS (1024)
#endif

/*
** Returns non-zero if the character should be treated as a directory
** separator.
*/
#ifndef winIsDirSep
#  define winIsDirSep(a)                (((a) == '/') || ((a) == '\\'))
#endif

/*
** This macro is used when a local variable is set to a value that is
** [sometimes] not used by the code (e.g. via conditional compilation).
*/
#ifndef UNUSED_VARIABLE_VALUE
#  define UNUSED_VARIABLE_VALUE(x) (void)(x)
#endif

/*
** Returns the string that should be used as the directory separator.
*/
#ifndef winGetDirDep
#  ifdef __CYGWIN__
#    define winGetDirDep()              "/"
#  else
#    define winGetDirDep()              "\\"
#  endif
#endif

/*
** Do we need to manually define the Win32 file mapping APIs for use with WAL
** mode (e.g. these APIs are available in the Windows CE SDK; however, they
** are not present in the header file)?
*/
#if SQLITE_WIN32_FILEMAPPING_API && !defined(SQLITE_OMIT_WAL)
/*
................................................................................
#endif

#ifndef FILE_ATTRIBUTE_MASK
# define FILE_ATTRIBUTE_MASK     (0x0003FFF7)
#endif

#ifndef SQLITE_OMIT_WAL
/* Forward references to structures used for WAL */
typedef struct winShm winShm;           /* A connection to shared-memory */
typedef struct winShmNode winShmNode;   /* A region of shared-memory */
#endif

/*
** WinCE lacks native support for file locking so we have to fake it
** with some code of our own.
................................................................................
** 2:   Operating system is WinNT.
**
** In order to facilitate testing on a WinNT system, the test fixture
** can manually set this value to 1 to emulate Win98 behavior.
*/
#ifdef SQLITE_TEST
SQLITE_API int sqlite3_os_type = 0;
#elif !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && \
      defined(SQLITE_WIN32_HAS_ANSI) && defined(SQLITE_WIN32_HAS_WIDE)
static int sqlite3_os_type = 0;
#endif

#ifndef SYSCALL
#  define SYSCALL sqlite3_syscall_ptr
#endif

................................................................................
  { "GetVersionExA",           (SYSCALL)GetVersionExA,           0 },
#else
  { "GetVersionExA",           (SYSCALL)0,                       0 },
#endif

#define osGetVersionExA ((BOOL(WINAPI*)( \
        LPOSVERSIONINFOA))aSyscall[34].pCurrent)

#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
  { "GetVersionExW",           (SYSCALL)GetVersionExW,           0 },
#else
  { "GetVersionExW",           (SYSCALL)0,                       0 },
#endif

#define osGetVersionExW ((BOOL(WINAPI*)( \
        LPOSVERSIONINFOW))aSyscall[35].pCurrent)

  { "HeapAlloc",               (SYSCALL)HeapAlloc,               0 },

#define osHeapAlloc ((LPVOID(WINAPI*)(HANDLE,DWORD, \
        SIZE_T))aSyscall[36].pCurrent)

#if !SQLITE_OS_WINRT
  { "HeapCreate",              (SYSCALL)HeapCreate,              0 },
#else
  { "HeapCreate",              (SYSCALL)0,                       0 },
#endif

#define osHeapCreate ((HANDLE(WINAPI*)(DWORD,SIZE_T, \
        SIZE_T))aSyscall[37].pCurrent)

#if !SQLITE_OS_WINRT
  { "HeapDestroy",             (SYSCALL)HeapDestroy,             0 },
#else
  { "HeapDestroy",             (SYSCALL)0,                       0 },
#endif

#define osHeapDestroy ((BOOL(WINAPI*)(HANDLE))aSyscall[38].pCurrent)

  { "HeapFree",                (SYSCALL)HeapFree,                0 },

#define osHeapFree ((BOOL(WINAPI*)(HANDLE,DWORD,LPVOID))aSyscall[39].pCurrent)

  { "HeapReAlloc",             (SYSCALL)HeapReAlloc,             0 },

#define osHeapReAlloc ((LPVOID(WINAPI*)(HANDLE,DWORD,LPVOID, \
        SIZE_T))aSyscall[40].pCurrent)

  { "HeapSize",                (SYSCALL)HeapSize,                0 },

#define osHeapSize ((SIZE_T(WINAPI*)(HANDLE,DWORD, \
        LPCVOID))aSyscall[41].pCurrent)

#if !SQLITE_OS_WINRT
  { "HeapValidate",            (SYSCALL)HeapValidate,            0 },
#else
  { "HeapValidate",            (SYSCALL)0,                       0 },
#endif

#define osHeapValidate ((BOOL(WINAPI*)(HANDLE,DWORD, \
        LPCVOID))aSyscall[42].pCurrent)

#if defined(SQLITE_WIN32_HAS_ANSI) && !defined(SQLITE_OMIT_LOAD_EXTENSION)
  { "LoadLibraryA",            (SYSCALL)LoadLibraryA,            0 },
#else
  { "LoadLibraryA",            (SYSCALL)0,                       0 },
#endif

#define osLoadLibraryA ((HMODULE(WINAPI*)(LPCSTR))aSyscall[43].pCurrent)

#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE) && \
        !defined(SQLITE_OMIT_LOAD_EXTENSION)
  { "LoadLibraryW",            (SYSCALL)LoadLibraryW,            0 },
#else
  { "LoadLibraryW",            (SYSCALL)0,                       0 },
#endif

#define osLoadLibraryW ((HMODULE(WINAPI*)(LPCWSTR))aSyscall[44].pCurrent)

#if !SQLITE_OS_WINRT
  { "LocalFree",               (SYSCALL)LocalFree,               0 },
#else
  { "LocalFree",               (SYSCALL)0,                       0 },
#endif

#define osLocalFree ((HLOCAL(WINAPI*)(HLOCAL))aSyscall[45].pCurrent)

#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
  { "LockFile",                (SYSCALL)LockFile,                0 },
#else
  { "LockFile",                (SYSCALL)0,                       0 },
#endif

#ifndef osLockFile
#define osLockFile ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
        DWORD))aSyscall[46].pCurrent)
#endif

#if !SQLITE_OS_WINCE
  { "LockFileEx",              (SYSCALL)LockFileEx,              0 },
#else
  { "LockFileEx",              (SYSCALL)0,                       0 },
#endif

#ifndef osLockFileEx
#define osLockFileEx ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD,DWORD, \
        LPOVERLAPPED))aSyscall[47].pCurrent)
#endif

#if SQLITE_OS_WINCE || (!SQLITE_OS_WINRT && !defined(SQLITE_OMIT_WAL))
  { "MapViewOfFile",           (SYSCALL)MapViewOfFile,           0 },
#else
  { "MapViewOfFile",           (SYSCALL)0,                       0 },
#endif

#define osMapViewOfFile ((LPVOID(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
        SIZE_T))aSyscall[48].pCurrent)

  { "MultiByteToWideChar",     (SYSCALL)MultiByteToWideChar,     0 },

#define osMultiByteToWideChar ((int(WINAPI*)(UINT,DWORD,LPCSTR,int,LPWSTR, \
        int))aSyscall[49].pCurrent)

  { "QueryPerformanceCounter", (SYSCALL)QueryPerformanceCounter, 0 },

#define osQueryPerformanceCounter ((BOOL(WINAPI*)( \
        LARGE_INTEGER*))aSyscall[50].pCurrent)

  { "ReadFile",                (SYSCALL)ReadFile,                0 },

#define osReadFile ((BOOL(WINAPI*)(HANDLE,LPVOID,DWORD,LPDWORD, \
        LPOVERLAPPED))aSyscall[51].pCurrent)

  { "SetEndOfFile",            (SYSCALL)SetEndOfFile,            0 },

#define osSetEndOfFile ((BOOL(WINAPI*)(HANDLE))aSyscall[52].pCurrent)

#if !SQLITE_OS_WINRT
  { "SetFilePointer",          (SYSCALL)SetFilePointer,          0 },
#else
  { "SetFilePointer",          (SYSCALL)0,                       0 },
#endif

#define osSetFilePointer ((DWORD(WINAPI*)(HANDLE,LONG,PLONG, \
        DWORD))aSyscall[53].pCurrent)

#if !SQLITE_OS_WINRT
  { "Sleep",                   (SYSCALL)Sleep,                   0 },
#else
  { "Sleep",                   (SYSCALL)0,                       0 },
#endif

#define osSleep ((VOID(WINAPI*)(DWORD))aSyscall[54].pCurrent)

  { "SystemTimeToFileTime",    (SYSCALL)SystemTimeToFileTime,    0 },

#define osSystemTimeToFileTime ((BOOL(WINAPI*)(CONST SYSTEMTIME*, \
        LPFILETIME))aSyscall[55].pCurrent)

#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
  { "UnlockFile",              (SYSCALL)UnlockFile,              0 },
#else
  { "UnlockFile",              (SYSCALL)0,                       0 },
#endif

#ifndef osUnlockFile
#define osUnlockFile ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
        DWORD))aSyscall[56].pCurrent)
#endif

#if !SQLITE_OS_WINCE
  { "UnlockFileEx",            (SYSCALL)UnlockFileEx,            0 },
#else
  { "UnlockFileEx",            (SYSCALL)0,                       0 },
#endif

#define osUnlockFileEx ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
        LPOVERLAPPED))aSyscall[57].pCurrent)

#if SQLITE_OS_WINCE || !defined(SQLITE_OMIT_WAL)
  { "UnmapViewOfFile",         (SYSCALL)UnmapViewOfFile,         0 },
#else
  { "UnmapViewOfFile",         (SYSCALL)0,                       0 },
#endif

#define osUnmapViewOfFile ((BOOL(WINAPI*)(LPCVOID))aSyscall[58].pCurrent)

  { "WideCharToMultiByte",     (SYSCALL)WideCharToMultiByte,     0 },

#define osWideCharToMultiByte ((int(WINAPI*)(UINT,DWORD,LPCWSTR,int,LPSTR,int, \
        LPCSTR,LPBOOL))aSyscall[59].pCurrent)

  { "WriteFile",               (SYSCALL)WriteFile,               0 },

#define osWriteFile ((BOOL(WINAPI*)(HANDLE,LPCVOID,DWORD,LPDWORD, \
        LPOVERLAPPED))aSyscall[60].pCurrent)

#if SQLITE_OS_WINRT
  { "CreateEventExW",          (SYSCALL)CreateEventExW,          0 },
#else
  { "CreateEventExW",          (SYSCALL)0,                       0 },
#endif

#define osCreateEventExW ((HANDLE(WINAPI*)(LPSECURITY_ATTRIBUTES,LPCWSTR, \
        DWORD,DWORD))aSyscall[61].pCurrent)

#if !SQLITE_OS_WINRT
  { "WaitForSingleObject",     (SYSCALL)WaitForSingleObject,     0 },
#else
  { "WaitForSingleObject",     (SYSCALL)0,                       0 },
#endif

#define osWaitForSingleObject ((DWORD(WINAPI*)(HANDLE, \
        DWORD))aSyscall[62].pCurrent)

#if SQLITE_OS_WINRT
  { "WaitForSingleObjectEx",   (SYSCALL)WaitForSingleObjectEx,   0 },
#else
  { "WaitForSingleObjectEx",   (SYSCALL)0,                       0 },
#endif

#define osWaitForSingleObjectEx ((DWORD(WINAPI*)(HANDLE,DWORD, \
        BOOL))aSyscall[63].pCurrent)

#if SQLITE_OS_WINRT
  { "SetFilePointerEx",        (SYSCALL)SetFilePointerEx,        0 },
#else
  { "SetFilePointerEx",        (SYSCALL)0,                       0 },
#endif

#define osSetFilePointerEx ((BOOL(WINAPI*)(HANDLE,LARGE_INTEGER, \
        PLARGE_INTEGER,DWORD))aSyscall[64].pCurrent)

#if SQLITE_OS_WINRT
  { "GetFileInformationByHandleEx", (SYSCALL)GetFileInformationByHandleEx, 0 },
#else
  { "GetFileInformationByHandleEx", (SYSCALL)0,                  0 },
#endif

#define osGetFileInformationByHandleEx ((BOOL(WINAPI*)(HANDLE, \
        FILE_INFO_BY_HANDLE_CLASS,LPVOID,DWORD))aSyscall[65].pCurrent)

#if SQLITE_OS_WINRT && !defined(SQLITE_OMIT_WAL)
  { "MapViewOfFileFromApp",    (SYSCALL)MapViewOfFileFromApp,    0 },
#else
  { "MapViewOfFileFromApp",    (SYSCALL)0,                       0 },
#endif

#define osMapViewOfFileFromApp ((LPVOID(WINAPI*)(HANDLE,ULONG,ULONG64, \
        SIZE_T))aSyscall[66].pCurrent)

#if SQLITE_OS_WINRT
  { "CreateFile2",             (SYSCALL)CreateFile2,             0 },
#else
  { "CreateFile2",             (SYSCALL)0,                       0 },
#endif

#define osCreateFile2 ((HANDLE(WINAPI*)(LPCWSTR,DWORD,DWORD,DWORD, \
        LPCREATEFILE2_EXTENDED_PARAMETERS))aSyscall[67].pCurrent)

#if SQLITE_OS_WINRT && !defined(SQLITE_OMIT_LOAD_EXTENSION)
  { "LoadPackagedLibrary",     (SYSCALL)LoadPackagedLibrary,     0 },
#else
  { "LoadPackagedLibrary",     (SYSCALL)0,                       0 },
#endif

#define osLoadPackagedLibrary ((HMODULE(WINAPI*)(LPCWSTR, \
        DWORD))aSyscall[68].pCurrent)

#if SQLITE_OS_WINRT
  { "GetTickCount64",          (SYSCALL)GetTickCount64,          0 },
#else
  { "GetTickCount64",          (SYSCALL)0,                       0 },
#endif

#define osGetTickCount64 ((ULONGLONG(WINAPI*)(VOID))aSyscall[69].pCurrent)

#if SQLITE_OS_WINRT
  { "GetNativeSystemInfo",     (SYSCALL)GetNativeSystemInfo,     0 },
#else
  { "GetNativeSystemInfo",     (SYSCALL)0,                       0 },
#endif

#define osGetNativeSystemInfo ((VOID(WINAPI*)( \
        LPSYSTEM_INFO))aSyscall[70].pCurrent)

#if defined(SQLITE_WIN32_HAS_ANSI)
  { "OutputDebugStringA",      (SYSCALL)OutputDebugStringA,      0 },
#else
  { "OutputDebugStringA",      (SYSCALL)0,                       0 },
#endif

#define osOutputDebugStringA ((VOID(WINAPI*)(LPCSTR))aSyscall[71].pCurrent)

#if defined(SQLITE_WIN32_HAS_WIDE)
  { "OutputDebugStringW",      (SYSCALL)OutputDebugStringW,      0 },
#else
  { "OutputDebugStringW",      (SYSCALL)0,                       0 },
#endif

#define osOutputDebugStringW ((VOID(WINAPI*)(LPCWSTR))aSyscall[72].pCurrent)

  { "GetProcessHeap",          (SYSCALL)GetProcessHeap,          0 },

#define osGetProcessHeap ((HANDLE(WINAPI*)(VOID))aSyscall[73].pCurrent)

#if SQLITE_OS_WINRT && !defined(SQLITE_OMIT_WAL)
  { "CreateFileMappingFromApp", (SYSCALL)CreateFileMappingFromApp, 0 },
#else
  { "CreateFileMappingFromApp", (SYSCALL)0,                      0 },
#endif

#define osCreateFileMappingFromApp ((HANDLE(WINAPI*)(HANDLE, \
        LPSECURITY_ATTRIBUTES,ULONG,ULONG64,LPCWSTR))aSyscall[74].pCurrent)

}; /* End of the overrideable system calls */

/*
** This is the xSetSystemCall() method of sqlite3_vfs for all of the
** "win32" VFSes.  Return SQLITE_OK opon successfully updating the
** system call pointer, or SQLITE_NOTFOUND if there is no configurable
................................................................................
** Here is an interesting observation:  Win95, Win98, and WinME lack
** the LockFileEx() API.  But we can still statically link against that
** API as long as we don't call it when running Win95/98/ME.  A call to
** this routine is used to determine if the host is Win95/98/ME or
** WinNT/2K/XP so that we will know whether or not we can safely call
** the LockFileEx() API.
*/
#ifndef NTDDI_WIN8
#  define NTDDI_WIN8                        0x06020000
#endif

#if SQLITE_OS_WINCE || SQLITE_OS_WINRT || !defined(SQLITE_WIN32_HAS_ANSI)
# define osIsNT()  (1)
#elif !defined(SQLITE_WIN32_HAS_WIDE)
# define osIsNT()  (0)
#else
  static int osIsNT(void){
    if( sqlite3_os_type==0 ){
#if defined(NTDDI_VERSION) && NTDDI_VERSION >= NTDDI_WIN8
      OSVERSIONINFOW sInfo;
      sInfo.dwOSVersionInfoSize = sizeof(sInfo);
      osGetVersionExW(&sInfo);
#else
      OSVERSIONINFOA sInfo;
      sInfo.dwOSVersionInfoSize = sizeof(sInfo);
      osGetVersionExA(&sInfo);
#endif
      sqlite3_os_type = sInfo.dwPlatformId==VER_PLATFORM_WIN32_NT ? 2 : 1;
    }
    return sqlite3_os_type==2;
  }
#endif

#ifdef SQLITE_WIN32_MALLOC
................................................................................
  assert( hHeap!=INVALID_HANDLE_VALUE );
#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
  assert ( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
#endif
  assert( nBytes>=0 );
  p = osHeapAlloc(hHeap, SQLITE_WIN32_HEAP_FLAGS, (SIZE_T)nBytes);
  if( !p ){
    sqlite3_log(SQLITE_NOMEM, "failed to HeapAlloc %u bytes (%lu), heap=%p",
                nBytes, osGetLastError(), (void*)hHeap);
  }
  return p;
}

/*
** Free memory.
................................................................................
  assert( hHeap!=0 );
  assert( hHeap!=INVALID_HANDLE_VALUE );
#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
  assert ( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior) );
#endif
  if( !pPrior ) return; /* Passing NULL to HeapFree is undefined. */
  if( !osHeapFree(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior) ){
    sqlite3_log(SQLITE_NOMEM, "failed to HeapFree block %p (%lu), heap=%p",
                pPrior, osGetLastError(), (void*)hHeap);
  }
}

/*
** Change the size of an existing memory allocation
*/
................................................................................
  assert( nBytes>=0 );
  if( !pPrior ){
    p = osHeapAlloc(hHeap, SQLITE_WIN32_HEAP_FLAGS, (SIZE_T)nBytes);
  }else{
    p = osHeapReAlloc(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior, (SIZE_T)nBytes);
  }
  if( !p ){
    sqlite3_log(SQLITE_NOMEM, "failed to %s %u bytes (%lu), heap=%p",
                pPrior ? "HeapReAlloc" : "HeapAlloc", nBytes, osGetLastError(),
                (void*)hHeap);
  }
  return p;
}

/*
................................................................................
  assert( hHeap!=INVALID_HANDLE_VALUE );
#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
  assert ( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
#endif
  if( !p ) return 0;
  n = osHeapSize(hHeap, SQLITE_WIN32_HEAP_FLAGS, p);
  if( n==(SIZE_T)-1 ){
    sqlite3_log(SQLITE_NOMEM, "failed to HeapSize block %p (%lu), heap=%p",
                p, osGetLastError(), (void*)hHeap);
    return 0;
  }
  return (int)n;
}

/*
................................................................................
#if !SQLITE_OS_WINRT && SQLITE_WIN32_HEAP_CREATE
  if( !pWinMemData->hHeap ){
    pWinMemData->hHeap = osHeapCreate(SQLITE_WIN32_HEAP_FLAGS,
                                      SQLITE_WIN32_HEAP_INIT_SIZE,
                                      SQLITE_WIN32_HEAP_MAX_SIZE);
    if( !pWinMemData->hHeap ){
      sqlite3_log(SQLITE_NOMEM,
          "failed to HeapCreate (%lu), flags=%u, initSize=%u, maxSize=%u",
          osGetLastError(), SQLITE_WIN32_HEAP_FLAGS,
          SQLITE_WIN32_HEAP_INIT_SIZE, SQLITE_WIN32_HEAP_MAX_SIZE);
      return SQLITE_NOMEM;
    }
    pWinMemData->bOwned = TRUE;
    assert( pWinMemData->bOwned );
  }
#else
  pWinMemData->hHeap = osGetProcessHeap();
  if( !pWinMemData->hHeap ){
    sqlite3_log(SQLITE_NOMEM,
        "failed to GetProcessHeap (%lu)", osGetLastError());
    return SQLITE_NOMEM;
  }
  pWinMemData->bOwned = FALSE;
  assert( !pWinMemData->bOwned );
#endif
  assert( pWinMemData->hHeap!=0 );
  assert( pWinMemData->hHeap!=INVALID_HANDLE_VALUE );
................................................................................
  if( pWinMemData->hHeap ){
    assert( pWinMemData->hHeap!=INVALID_HANDLE_VALUE );
#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
    assert( osHeapValidate(pWinMemData->hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
#endif
    if( pWinMemData->bOwned ){
      if( !osHeapDestroy(pWinMemData->hHeap) ){
        sqlite3_log(SQLITE_NOMEM, "failed to HeapDestroy (%lu), heap=%p",
                    osGetLastError(), (void*)pWinMemData->hHeap);
      }
      pWinMemData->bOwned = FALSE;
    }
    pWinMemData->hHeap = NULL;
  }
}
................................................................................
#endif /* SQLITE_WIN32_MALLOC */

/*
** Convert a UTF-8 string to Microsoft Unicode (UTF-16?). 
**
** Space to hold the returned string is obtained from malloc.
*/
static LPWSTR winUtf8ToUnicode(const char *zFilename){
  int nChar;
  LPWSTR zWideFilename;

  nChar = osMultiByteToWideChar(CP_UTF8, 0, zFilename, -1, NULL, 0);
  if( nChar==0 ){
    return 0;
  }
................................................................................
  return zWideFilename;
}

/*
** Convert Microsoft Unicode to UTF-8.  Space to hold the returned string is
** obtained from sqlite3_malloc().
*/
static char *winUnicodeToUtf8(LPCWSTR zWideFilename){
  int nByte;
  char *zFilename;

  nByte = osWideCharToMultiByte(CP_UTF8, 0, zWideFilename, -1, 0, 0, 0, 0);
  if( nByte == 0 ){
    return 0;
  }
................................................................................
/*
** Convert an ANSI string to Microsoft Unicode, based on the
** current codepage settings for file apis.
** 
** Space to hold the returned string is obtained
** from sqlite3_malloc.
*/
static LPWSTR winMbcsToUnicode(const char *zFilename){
  int nByte;
  LPWSTR zMbcsFilename;
  int codepage = osAreFileApisANSI() ? CP_ACP : CP_OEMCP;

  nByte = osMultiByteToWideChar(codepage, 0, zFilename, -1, NULL,
                                0)*sizeof(WCHAR);
  if( nByte==0 ){
................................................................................
/*
** Convert Microsoft Unicode to multi-byte character string, based on the
** user's ANSI codepage.
**
** Space to hold the returned string is obtained from
** sqlite3_malloc().
*/
static char *winUnicodeToMbcs(LPCWSTR zWideFilename){
  int nByte;
  char *zFilename;
  int codepage = osAreFileApisANSI() ? CP_ACP : CP_OEMCP;

  nByte = osWideCharToMultiByte(codepage, 0, zWideFilename, -1, 0, 0, 0, 0);
  if( nByte == 0 ){
    return 0;
................................................................................
** Convert multibyte character string to UTF-8.  Space to hold the
** returned string is obtained from sqlite3_malloc().
*/
SQLITE_API char *sqlite3_win32_mbcs_to_utf8(const char *zFilename){
  char *zFilenameUtf8;
  LPWSTR zTmpWide;

  zTmpWide = winMbcsToUnicode(zFilename);
  if( zTmpWide==0 ){
    return 0;
  }
  zFilenameUtf8 = winUnicodeToUtf8(zTmpWide);
  sqlite3_free(zTmpWide);
  return zFilenameUtf8;
}

/*
** Convert UTF-8 to multibyte character string.  Space to hold the 
** returned string is obtained from sqlite3_malloc().
*/
SQLITE_API char *sqlite3_win32_utf8_to_mbcs(const char *zFilename){
  char *zFilenameMbcs;
  LPWSTR zTmpWide;

  zTmpWide = winUtf8ToUnicode(zFilename);
  if( zTmpWide==0 ){
    return 0;
  }
  zFilenameMbcs = winUnicodeToMbcs(zTmpWide);
  sqlite3_free(zTmpWide);
  return zFilenameMbcs;
}

/*
** This function sets the data directory or the temporary directory based on
** the provided arguments.  The type argument must be 1 in order to set the
................................................................................
  assert( !ppDirectory || type==SQLITE_WIN32_DATA_DIRECTORY_TYPE
          || type==SQLITE_WIN32_TEMP_DIRECTORY_TYPE
  );
  assert( !ppDirectory || sqlite3MemdebugHasType(*ppDirectory, MEMTYPE_HEAP) );
  if( ppDirectory ){
    char *zValueUtf8 = 0;
    if( zValue && zValue[0] ){
      zValueUtf8 = winUnicodeToUtf8(zValue);
      if ( zValueUtf8==0 ){
        return SQLITE_NOMEM;
      }
    }
    sqlite3_free(*ppDirectory);
    *ppDirectory = zValueUtf8;
    return SQLITE_OK;
  }
  return SQLITE_ERROR;
}

/*
** The return value of winGetLastErrorMsg
** is zero if the error message fits in the buffer, or non-zero
** otherwise (if the message was truncated).
*/
static int winGetLastErrorMsg(DWORD lastErrno, int nBuf, char *zBuf){
  /* FormatMessage returns 0 on failure.  Otherwise it
  ** returns the number of TCHARs written to the output
  ** buffer, excluding the terminating null char.
  */
  DWORD dwLen = 0;
  char *zOut = 0;

  if( osIsNT() ){
#if SQLITE_OS_WINRT
    WCHAR zTempWide[SQLITE_WIN32_MAX_ERRMSG_CHARS+1];
    dwLen = osFormatMessageW(FORMAT_MESSAGE_FROM_SYSTEM |
                             FORMAT_MESSAGE_IGNORE_INSERTS,
                             NULL,
                             lastErrno,
                             0,
                             zTempWide,
                             SQLITE_WIN32_MAX_ERRMSG_CHARS,
                             0);
#else
    LPWSTR zTempWide = NULL;
    dwLen = osFormatMessageW(FORMAT_MESSAGE_ALLOCATE_BUFFER |
                             FORMAT_MESSAGE_FROM_SYSTEM |
                             FORMAT_MESSAGE_IGNORE_INSERTS,
                             NULL,
................................................................................
                             (LPWSTR) &zTempWide,
                             0,
                             0);
#endif
    if( dwLen > 0 ){
      /* allocate a buffer and convert to UTF8 */
      sqlite3BeginBenignMalloc();
      zOut = winUnicodeToUtf8(zTempWide);
      sqlite3EndBenignMalloc();
#if !SQLITE_OS_WINRT
      /* free the system buffer allocated by FormatMessage */
      osLocalFree(zTempWide);
#endif
    }
  }
................................................................................
  const char *zPath,              /* File path associated with error */
  int iLine                       /* Source line number where error occurred */
){
  char zMsg[500];                 /* Human readable error text */
  int i;                          /* Loop counter */

  zMsg[0] = 0;
  winGetLastErrorMsg(lastErrno, sizeof(zMsg), zMsg);
  assert( errcode!=SQLITE_OK );
  if( zPath==0 ) zPath = "";
  for(i=0; zMsg[i] && zMsg[i]!='\r' && zMsg[i]!='\n'; i++){}
  zMsg[i] = 0;
  sqlite3_log(errcode,
      "os_win.c:%d: (%lu) %s(%s) - %s",
      iLine, lastErrno, zFunc, zPath, zMsg
................................................................................
*/
#ifndef SQLITE_WIN32_IOERR_RETRY
# define SQLITE_WIN32_IOERR_RETRY 10
#endif
#ifndef SQLITE_WIN32_IOERR_RETRY_DELAY
# define SQLITE_WIN32_IOERR_RETRY_DELAY 25
#endif
static int winIoerrRetry = SQLITE_WIN32_IOERR_RETRY;
static int winIoerrRetryDelay = SQLITE_WIN32_IOERR_RETRY_DELAY;

/*
** If a ReadFile() or WriteFile() error occurs, invoke this routine
** to see if it should be retried.  Return TRUE to retry.  Return FALSE
** to give up with an error.
*/
static int winRetryIoerr(int *pnRetry, DWORD *pError){
  DWORD e = osGetLastError();
  if( *pnRetry>=winIoerrRetry ){
    if( pError ){
      *pError = e;
    }
    return 0;
  }
  if( e==ERROR_ACCESS_DENIED ||
      e==ERROR_LOCK_VIOLATION ||
      e==ERROR_SHARING_VIOLATION ){
    sqlite3_win32_sleep(winIoerrRetryDelay*(1+*pnRetry));
    ++*pnRetry;
    return 1;
  }
  if( pError ){
    *pError = e;
  }
  return 0;
}

/*
** Log a I/O error retry episode.
*/
static void winLogIoerr(int nRetry){
  if( nRetry ){
    sqlite3_log(SQLITE_IOERR, 
      "delayed %dms for lock/sharing conflict",
      winIoerrRetryDelay*nRetry*(nRetry+1)/2
    );
  }
}

#if SQLITE_OS_WINCE
/*************************************************************************
** This section contains code for WinCE only.
................................................................................
static int winceCreateLock(const char *zFilename, winFile *pFile){
  LPWSTR zTok;
  LPWSTR zName;
  DWORD lastErrno;
  BOOL bLogged = FALSE;
  BOOL bInit = TRUE;

  zName = winUtf8ToUnicode(zFilename);
  if( zName==0 ){
    /* out of memory */
    return SQLITE_IOERR_NOMEM;
  }

  /* Initialize the local lockdata */
  memset(&pFile->local, 0, sizeof(pFile->local));
................................................................................
    if (*zTok == '\\') *zTok = '_';
  }

  /* Create/open the named mutex */
  pFile->hMutex = osCreateMutexW(NULL, FALSE, zName);
  if (!pFile->hMutex){
    pFile->lastErrno = osGetLastError();
    sqlite3_free(zName);
    return winLogError(SQLITE_IOERR, pFile->lastErrno,
                       "winceCreateLock1", zFilename);


  }

  /* Acquire the mutex before continuing */
  winceMutexAcquire(pFile->hMutex);
  
  /* Since the names of named mutexes, semaphores, file mappings etc are 
  ** case-sensitive, take advantage of that by uppercasing the mutex name
................................................................................
  /*
  ** NOTE: Windows CE is handled differently here due its lack of the Win32
  **       API LockFile.
  */
  return winceLockFile(phFile, offsetLow, offsetHigh,
                       numBytesLow, numBytesHigh);
#else
  if( osIsNT() ){
    OVERLAPPED ovlp;
    memset(&ovlp, 0, sizeof(OVERLAPPED));
    ovlp.Offset = offsetLow;
    ovlp.OffsetHigh = offsetHigh;
    return osLockFileEx(*phFile, flags, 0, numBytesLow, numBytesHigh, &ovlp);
  }else{
    return osLockFile(*phFile, offsetLow, offsetHigh, numBytesLow,
................................................................................
  /*
  ** NOTE: Windows CE is handled differently here due its lack of the Win32
  **       API UnlockFile.
  */
  return winceUnlockFile(phFile, offsetLow, offsetHigh,
                         numBytesLow, numBytesHigh);
#else
  if( osIsNT() ){
    OVERLAPPED ovlp;
    memset(&ovlp, 0, sizeof(OVERLAPPED));
    ovlp.Offset = offsetLow;
    ovlp.OffsetHigh = offsetHigh;
    return osUnlockFileEx(*phFile, 0, numBytesLow, numBytesHigh, &ovlp);
  }else{
    return osUnlockFile(*phFile, offsetLow, offsetHigh, numBytesLow,
................................................................................
#endif

/*
** Move the current position of the file handle passed as the first 
** argument to offset iOffset within the file. If successful, return 0. 
** Otherwise, set pFile->lastErrno and return non-zero.
*/
static int winSeekFile(winFile *pFile, sqlite3_int64 iOffset){
#if !SQLITE_OS_WINRT
  LONG upperBits;                 /* Most sig. 32 bits of new offset */
  LONG lowerBits;                 /* Least sig. 32 bits of new offset */
  DWORD dwRet;                    /* Value returned by SetFilePointer() */
  DWORD lastErrno;                /* Value returned by GetLastError() */

  OSTRACE(("SEEK file=%p, offset=%lld\n", pFile->h, iOffset));
................................................................................
  */
  dwRet = osSetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);

  if( (dwRet==INVALID_SET_FILE_POINTER
      && ((lastErrno = osGetLastError())!=NO_ERROR)) ){
    pFile->lastErrno = lastErrno;
    winLogError(SQLITE_IOERR_SEEK, pFile->lastErrno,
                "winSeekFile", pFile->zPath);
    OSTRACE(("SEEK file=%p, rc=SQLITE_IOERR_SEEK\n", pFile->h));
    return 1;
  }

  OSTRACE(("SEEK file=%p, rc=SQLITE_OK\n", pFile->h));
  return 0;
#else
................................................................................

  x.QuadPart = iOffset;
  bRet = osSetFilePointerEx(pFile->h, x, 0, FILE_BEGIN);

  if(!bRet){
    pFile->lastErrno = osGetLastError();
    winLogError(SQLITE_IOERR_SEEK, pFile->lastErrno,
                "winSeekFile", pFile->zPath);
    OSTRACE(("SEEK file=%p, rc=SQLITE_IOERR_SEEK\n", pFile->h));
    return 1;
  }

  OSTRACE(("SEEK file=%p, rc=SQLITE_OK\n", pFile->h));
  return 0;
#endif
}

#if SQLITE_MAX_MMAP_SIZE>0
/* Forward references to VFS helper methods used for memory mapped files */
static int winMapfile(winFile*, sqlite3_int64);
static int winUnmapfile(winFile*);
#endif

/*
** Close a file.
**
** It is reported that an attempt to close a handle might sometimes
................................................................................
      amt -= nCopy;
      offset += nCopy;
    }
  }
#endif

#if SQLITE_OS_WINCE
  if( winSeekFile(pFile, offset) ){
    OSTRACE(("READ file=%p, rc=SQLITE_FULL\n", pFile->h));
    return SQLITE_FULL;
  }
  while( !osReadFile(pFile->h, pBuf, amt, &nRead, 0) ){
#else
  memset(&overlapped, 0, sizeof(OVERLAPPED));
  overlapped.Offset = (LONG)(offset & 0xffffffff);
  overlapped.OffsetHigh = (LONG)((offset>>32) & 0x7fffffff);
  while( !osReadFile(pFile->h, pBuf, amt, &nRead, &overlapped) &&
         osGetLastError()!=ERROR_HANDLE_EOF ){
#endif
    DWORD lastErrno;
    if( winRetryIoerr(&nRetry, &lastErrno) ) continue;
    pFile->lastErrno = lastErrno;
    OSTRACE(("READ file=%p, rc=SQLITE_IOERR_READ\n", pFile->h));
    return winLogError(SQLITE_IOERR_READ, pFile->lastErrno,
                       "winRead", pFile->zPath);
  }
  winLogIoerr(nRetry);
  if( nRead<(DWORD)amt ){
    /* Unread parts of the buffer must be zero-filled */
    memset(&((char*)pBuf)[nRead], 0, amt-nRead);
    OSTRACE(("READ file=%p, rc=SQLITE_IOERR_SHORT_READ\n", pFile->h));
    return SQLITE_IOERR_SHORT_READ;
  }

................................................................................
      amt -= nCopy;
      offset += nCopy;
    }
  }
#endif

#if SQLITE_OS_WINCE
  rc = winSeekFile(pFile, offset);
  if( rc==0 ){
#else
  {
#endif
#if !SQLITE_OS_WINCE
    OVERLAPPED overlapped;        /* The offset for WriteFile. */
#endif
................................................................................

    while( nRem>0 ){
#if SQLITE_OS_WINCE
      if( !osWriteFile(pFile->h, aRem, nRem, &nWrite, 0) ){
#else
      if( !osWriteFile(pFile->h, aRem, nRem, &nWrite, &overlapped) ){
#endif
        if( winRetryIoerr(&nRetry, &lastErrno) ) continue;
        break;
      }
      assert( nWrite==0 || nWrite<=(DWORD)nRem );
      if( nWrite==0 || nWrite>(DWORD)nRem ){
        lastErrno = osGetLastError();
        break;
      }
................................................................................
    }
  }

  if( rc ){
    if(   ( pFile->lastErrno==ERROR_HANDLE_DISK_FULL )
       || ( pFile->lastErrno==ERROR_DISK_FULL )){
      OSTRACE(("WRITE file=%p, rc=SQLITE_FULL\n", pFile->h));
      return winLogError(SQLITE_FULL, pFile->lastErrno,
                         "winWrite1", pFile->zPath);
    }
    OSTRACE(("WRITE file=%p, rc=SQLITE_IOERR_WRITE\n", pFile->h));
    return winLogError(SQLITE_IOERR_WRITE, pFile->lastErrno,
                       "winWrite2", pFile->zPath);
  }else{
    winLogIoerr(nRetry);
  }
  OSTRACE(("WRITE file=%p, rc=SQLITE_OK\n", pFile->h));
  return SQLITE_OK;
}

/*
** Truncate an open file to a specified size
................................................................................
  ** size).
  */
  if( pFile->szChunk>0 ){
    nByte = ((nByte + pFile->szChunk - 1)/pFile->szChunk) * pFile->szChunk;
  }

  /* SetEndOfFile() returns non-zero when successful, or zero when it fails. */
  if( winSeekFile(pFile, nByte) ){
    rc = winLogError(SQLITE_IOERR_TRUNCATE, pFile->lastErrno,
                     "winTruncate1", pFile->zPath);
  }else if( 0==osSetEndOfFile(pFile->h) &&
            ((lastErrno = osGetLastError())!=ERROR_USER_MAPPED_FILE) ){
    pFile->lastErrno = lastErrno;
    rc = winLogError(SQLITE_IOERR_TRUNCATE, pFile->lastErrno,
                     "winTruncate2", pFile->zPath);
................................................................................
  sqlite3_sync_count++;
#endif

  /* If we compiled with the SQLITE_NO_SYNC flag, then syncing is a
  ** no-op
  */
#ifdef SQLITE_NO_SYNC
  OSTRACE(("SYNC-NOP file=%p, rc=SQLITE_OK\n", pFile->h));
  return SQLITE_OK;
#else
  rc = osFlushFileBuffers(pFile->h);
  SimulateIOError( rc=FALSE );
  if( rc ){
    OSTRACE(("SYNC file=%p, rc=SQLITE_OK\n", pFile->h));
    return SQLITE_OK;
  }else{
    pFile->lastErrno = osGetLastError();
    OSTRACE(("SYNC file=%p, rc=SQLITE_IOERR_FSYNC\n", pFile->h));
    return winLogError(SQLITE_IOERR_FSYNC, pFile->lastErrno,
                       "winSync", pFile->zPath);
  }
#endif
}

/*
** Determine the current size of a file in bytes
*/
................................................................................

    lowerBits = osGetFileSize(pFile->h, &upperBits);
    *pSize = (((sqlite3_int64)upperBits)<<32) + lowerBits;
    if(   (lowerBits == INVALID_FILE_SIZE)
       && ((lastErrno = osGetLastError())!=NO_ERROR) ){
      pFile->lastErrno = lastErrno;
      rc = winLogError(SQLITE_IOERR_FSTAT, pFile->lastErrno,
                       "winFileSize", pFile->zPath);
    }
  }
#endif
  OSTRACE(("SIZE file=%p, pSize=%p, *pSize=%lld, rc=%s\n",
           pFile->h, pSize, *pSize, sqlite3ErrName(rc)));
  return rc;
}
................................................................................
#endif

/*
** Acquire a reader lock.
** Different API routines are called depending on whether or not this
** is Win9x or WinNT.
*/
static int winGetReadLock(winFile *pFile){
  int res;
  OSTRACE(("READ-LOCK file=%p, lock=%d\n", pFile->h, pFile->locktype));
  if( osIsNT() ){
#if SQLITE_OS_WINCE
    /*
    ** NOTE: Windows CE is handled differently here due its lack of the Win32
    **       API LockFileEx.
    */
    res = winceLockFile(&pFile->h, SHARED_FIRST, 0, 1, 0);
#else
................................................................................
  OSTRACE(("READ-LOCK file=%p, rc=%s\n", pFile->h, sqlite3ErrName(res)));
  return res;
}

/*
** Undo a readlock
*/
static int winUnlockReadLock(winFile *pFile){
  int res;
  DWORD lastErrno;
  OSTRACE(("READ-UNLOCK file=%p, lock=%d\n", pFile->h, pFile->locktype));
  if( osIsNT() ){
    res = winUnlockFile(&pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
  }
#ifdef SQLITE_WIN32_HAS_ANSI
  else{
    res = winUnlockFile(&pFile->h, SHARED_FIRST+pFile->sharedLockByte, 0, 1, 0);
  }
#endif
  if( res==0 && ((lastErrno = osGetLastError())!=ERROR_NOT_LOCKED) ){
    pFile->lastErrno = lastErrno;
    winLogError(SQLITE_IOERR_UNLOCK, pFile->lastErrno,
                "winUnlockReadLock", pFile->zPath);
  }
  OSTRACE(("READ-UNLOCK file=%p, rc=%s\n", pFile->h, sqlite3ErrName(res)));
  return res;
}

/*
** Lock the file with the lock specified by parameter locktype - one
................................................................................
    }
  }

  /* Acquire a shared lock
  */
  if( locktype==SHARED_LOCK && res ){
    assert( pFile->locktype==NO_LOCK );
    res = winGetReadLock(pFile);
    if( res ){
      newLocktype = SHARED_LOCK;
    }else{
      lastErrno = osGetLastError();
    }
  }

................................................................................
    gotPendingLock = 0;
  }

  /* Acquire an EXCLUSIVE lock
  */
  if( locktype==EXCLUSIVE_LOCK && res ){
    assert( pFile->locktype>=SHARED_LOCK );
    res = winUnlockReadLock(pFile);
    res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS, SHARED_FIRST, 0,
                      SHARED_SIZE, 0);
    if( res ){
      newLocktype = EXCLUSIVE_LOCK;
    }else{
      lastErrno = osGetLastError();
      winGetReadLock(pFile);
    }
  }

  /* If we are holding a PENDING lock that ought to be released, then
  ** release it now.
  */
  if( gotPendingLock && locktype==SHARED_LOCK ){
................................................................................

  /* Update the state of the lock has held in the file descriptor then
  ** return the appropriate result code.
  */
  if( res ){
    rc = SQLITE_OK;
  }else{


    pFile->lastErrno = lastErrno;
    rc = SQLITE_BUSY;
    OSTRACE(("LOCK-FAIL file=%p, wanted=%d, got=%d\n",
             pFile->h, locktype, newLocktype));
  }
  pFile->locktype = (u8)newLocktype;
  OSTRACE(("LOCK file=%p, lock=%d, rc=%s\n",
           pFile->h, pFile->locktype, sqlite3ErrName(rc)));
  return rc;
}

................................................................................
  assert( pFile!=0 );
  assert( locktype<=SHARED_LOCK );
  OSTRACE(("UNLOCK file=%p, oldLock=%d(%d), newLock=%d\n",
           pFile->h, pFile->locktype, pFile->sharedLockByte, locktype));
  type = pFile->locktype;
  if( type>=EXCLUSIVE_LOCK ){
    winUnlockFile(&pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
    if( locktype==SHARED_LOCK && !winGetReadLock(pFile) ){
      /* This should never happen.  We should always be able to
      ** reacquire the read lock */
      rc = winLogError(SQLITE_IOERR_UNLOCK, osGetLastError(),
                       "winUnlock", pFile->zPath);
    }
  }
  if( type>=RESERVED_LOCK ){
    winUnlockFile(&pFile->h, RESERVED_BYTE, 0, 1, 0);
  }
  if( locktype==NO_LOCK && type>=SHARED_LOCK ){
    winUnlockReadLock(pFile);
  }
  if( type>=PENDING_LOCK ){
    winUnlockFile(&pFile->h, PENDING_BYTE, 0, 1, 0);
  }
  pFile->locktype = (u8)locktype;
  OSTRACE(("UNLOCK file=%p, lock=%d, rc=%s\n",
           pFile->h, pFile->locktype, sqlite3ErrName(rc)));
................................................................................
  }else if( (*pArg)==0 ){
    pFile->ctrlFlags &= ~mask;
  }else{
    pFile->ctrlFlags |= mask;
  }
}

/* Forward references to VFS helper methods used for temporary files */
static int winGetTempname(sqlite3_vfs *, char **);
static int winIsDir(const void *);
static BOOL winIsDriveLetterAndColon(const char *);


/*
** Control and query of the open file handle.
*/
static int winFileControl(sqlite3_file *id, int op, void *pArg){
  winFile *pFile = (winFile*)id;
  OSTRACE(("FCNTL file=%p, op=%d, pArg=%p\n", pFile->h, op, pArg));
................................................................................
      *(char**)pArg = sqlite3_mprintf("win32");
      OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
      return SQLITE_OK;
    }
    case SQLITE_FCNTL_WIN32_AV_RETRY: {
      int *a = (int*)pArg;
      if( a[0]>0 ){
        winIoerrRetry = a[0];
      }else{
        a[0] = winIoerrRetry;
      }
      if( a[1]>0 ){
        winIoerrRetryDelay = a[1];
      }else{
        a[1] = winIoerrRetryDelay;
      }
      OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
      return SQLITE_OK;
    }
    case SQLITE_FCNTL_TEMPFILENAME: {

      char *zTFile = 0;
      int rc = winGetTempname(pFile->pVfs, &zTFile);
      if( rc==SQLITE_OK ){
        *(char**)pArg = zTFile;
      }
      OSTRACE(("FCNTL file=%p, rc=%s\n", pFile->h, sqlite3ErrName(rc)));
      return rc;
    }
#if SQLITE_MAX_MMAP_SIZE>0
    case SQLITE_FCNTL_MMAP_SIZE: {
      i64 newLimit = *(i64*)pArg;
      int rc = SQLITE_OK;
      if( newLimit>sqlite3GlobalConfig.mxMmap ){
        newLimit = sqlite3GlobalConfig.mxMmap;
................................................................................
      if( newLimit>=0 && newLimit!=pFile->mmapSizeMax && pFile->nFetchOut==0 ){
        pFile->mmapSizeMax = newLimit;
        if( pFile->mmapSize>0 ){
          (void)winUnmapfile(pFile);
          rc = winMapfile(pFile, -1);
        }
      }
      OSTRACE(("FCNTL file=%p, rc=%s\n", pFile->h, sqlite3ErrName(rc)));
      return rc;
    }
#endif
  }
  OSTRACE(("FCNTL file=%p, rc=SQLITE_NOTFOUND\n", pFile->h));
  return SQLITE_NOTFOUND;
}
................................................................................
**
** This is not a VFS shared-memory method; it is a utility function called
** by VFS shared-memory methods.
*/
static void winShmPurge(sqlite3_vfs *pVfs, int deleteFlag){
  winShmNode **pp;
  winShmNode *p;

  assert( winShmMutexHeld() );
  OSTRACE(("SHM-PURGE pid=%lu, deleteFlag=%d\n",
           osGetCurrentProcessId(), deleteFlag));
  pp = &winShmNodeList;
  while( (p = *pp)!=0 ){
    if( p->nRef==0 ){
      int i;
      if( p->mutex ) sqlite3_mutex_free(p->mutex);
      for(i=0; i<p->nRegion; i++){
        BOOL bRc = osUnmapViewOfFile(p->aRegion[i].pMap);
        OSTRACE(("SHM-PURGE-UNMAP pid=%lu, region=%d, rc=%s\n",
                 osGetCurrentProcessId(), i, bRc ? "ok" : "failed"));
        UNUSED_VARIABLE_VALUE(bRc);
        bRc = osCloseHandle(p->aRegion[i].hMap);
        OSTRACE(("SHM-PURGE-CLOSE pid=%lu, region=%d, rc=%s\n",
                 osGetCurrentProcessId(), i, bRc ? "ok" : "failed"));
        UNUSED_VARIABLE_VALUE(bRc);
      }
      if( p->hFile.h!=NULL && p->hFile.h!=INVALID_HANDLE_VALUE ){
        SimulateIOErrorBenign(1);
        winClose((sqlite3_file *)&p->hFile);
        SimulateIOErrorBenign(0);
      }
      if( deleteFlag ){
................................................................................
    /* Check to see if another process is holding the dead-man switch.
    ** If not, truncate the file to zero length. 
    */
    if( winShmSystemLock(pShmNode, _SHM_WRLCK, WIN_SHM_DMS, 1)==SQLITE_OK ){
      rc = winTruncate((sqlite3_file *)&pShmNode->hFile, 0);
      if( rc!=SQLITE_OK ){
        rc = winLogError(SQLITE_IOERR_SHMOPEN, osGetLastError(),
                         "winOpenShm", pDbFd->zPath);
      }
    }
    if( rc==SQLITE_OK ){
      winShmSystemLock(pShmNode, _SHM_UNLCK, WIN_SHM_DMS, 1);
      rc = winShmSystemLock(pShmNode, _SHM_RDLCK, WIN_SHM_DMS, 1);
    }
    if( rc ) goto shm_open_err;
................................................................................
    /* The requested region is not mapped into this processes address space.
    ** Check to see if it has been allocated (i.e. if the wal-index file is
    ** large enough to contain the requested region).
    */
    rc = winFileSize((sqlite3_file *)&pShmNode->hFile, &sz);
    if( rc!=SQLITE_OK ){
      rc = winLogError(SQLITE_IOERR_SHMSIZE, osGetLastError(),
                       "winShmMap1", pDbFd->zPath);
      goto shmpage_out;
    }

    if( sz<nByte ){
      /* The requested memory region does not exist. If isWrite is set to
      ** zero, exit early. *pp will be set to NULL and SQLITE_OK returned.
      **
................................................................................
      ** Alternatively, if isWrite is non-zero, use ftruncate() to allocate
      ** the requested memory region.
      */
      if( !isWrite ) goto shmpage_out;
      rc = winTruncate((sqlite3_file *)&pShmNode->hFile, nByte);
      if( rc!=SQLITE_OK ){
        rc = winLogError(SQLITE_IOERR_SHMSIZE, osGetLastError(),
                         "winShmMap2", pDbFd->zPath);
        goto shmpage_out;
      }
    }

    /* Map the requested memory region into this processes address space. */
    apNew = (struct ShmRegion *)sqlite3_realloc(
        pShmNode->aRegion, (iRegion+1)*sizeof(apNew[0])
................................................................................
        OSTRACE(("SHM-MAP-MAP pid=%lu, region=%d, offset=%d, size=%d, rc=%s\n",
                 osGetCurrentProcessId(), pShmNode->nRegion, iOffset,
                 szRegion, pMap ? "ok" : "failed"));
      }
      if( !pMap ){
        pShmNode->lastErrno = osGetLastError();
        rc = winLogError(SQLITE_IOERR_SHMMAP, pShmNode->lastErrno,
                         "winShmMap3", pDbFd->zPath);
        if( hMap ) osCloseHandle(hMap);
        goto shmpage_out;
      }

      pShmNode->aRegion[pShmNode->nRegion].pMap = pMap;
      pShmNode->aRegion[pShmNode->nRegion].hMap = hMap;
      pShmNode->nRegion++;
................................................................................
  if( pFile->pMapRegion ){
    if( !osUnmapViewOfFile(pFile->pMapRegion) ){
      pFile->lastErrno = osGetLastError();
      OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, pMapRegion=%p, "
               "rc=SQLITE_IOERR_MMAP\n", osGetCurrentProcessId(), pFile,
               pFile->pMapRegion));
      return winLogError(SQLITE_IOERR_MMAP, pFile->lastErrno,
                         "winUnmapfile1", pFile->zPath);
    }
    pFile->pMapRegion = 0;
    pFile->mmapSize = 0;
    pFile->mmapSizeActual = 0;
  }
  if( pFile->hMap!=NULL ){
    if( !osCloseHandle(pFile->hMap) ){
      pFile->lastErrno = osGetLastError();
      OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, hMap=%p, rc=SQLITE_IOERR_MMAP\n",
               osGetCurrentProcessId(), pFile, pFile->hMap));
      return winLogError(SQLITE_IOERR_MMAP, pFile->lastErrno,
                         "winUnmapfile2", pFile->zPath);
    }
    pFile->hMap = NULL;
  }
  OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, rc=SQLITE_OK\n",
           osGetCurrentProcessId(), pFile));
  return SQLITE_OK;
}
................................................................................
    pFd->hMap = osCreateFileMappingA(pFd->h, NULL, protect,
                                (DWORD)((nMap>>32) & 0xffffffff),
                                (DWORD)(nMap & 0xffffffff), NULL);
#endif
    if( pFd->hMap==NULL ){
      pFd->lastErrno = osGetLastError();
      rc = winLogError(SQLITE_IOERR_MMAP, pFd->lastErrno,
                       "winMapfile1", pFd->zPath);
      /* Log the error, but continue normal operation using xRead/xWrite */
      OSTRACE(("MAP-FILE-CREATE pid=%lu, pFile=%p, rc=%s\n",
               osGetCurrentProcessId(), pFd, sqlite3ErrName(rc)));
      return SQLITE_OK;
    }
    assert( (nMap % winSysInfo.dwPageSize)==0 );
    assert( sizeof(SIZE_T)==sizeof(sqlite3_int64) || nMap<=0xffffffff );
#if SQLITE_OS_WINRT
    pNew = osMapViewOfFileFromApp(pFd->hMap, flags, 0, (SIZE_T)nMap);
#else
    pNew = osMapViewOfFile(pFd->hMap, flags, 0, 0, (SIZE_T)nMap);
#endif
    if( pNew==NULL ){
      osCloseHandle(pFd->hMap);
      pFd->hMap = NULL;
      pFd->lastErrno = osGetLastError();
      rc = winLogError(SQLITE_IOERR_MMAP, pFd->lastErrno,
                       "winMapfile2", pFd->zPath);
      /* Log the error, but continue normal operation using xRead/xWrite */
      OSTRACE(("MAP-FILE-MAP pid=%lu, pFile=%p, rc=%s\n",
               osGetCurrentProcessId(), pFd, sqlite3ErrName(rc)));
      return SQLITE_OK;
    }
    pFd->pMapRegion = pNew;
    pFd->mmapSize = nMap;
    pFd->mmapSizeActual = nMap;
  }

................................................................................
/****************************************************************************
**************************** sqlite3_vfs methods ****************************
**
** This division contains the implementation of methods on the
** sqlite3_vfs object.
*/

#if 0
/*
** Convert a filename from whatever the underlying operating system
** supports for filenames into UTF-8.  Space to hold the result is
** obtained from malloc and must be freed by the calling function.
*/
static char *winConvertToUtf8Filename(const void *zFilename){
  char *zConverted = 0;
  if( osIsNT() ){
    zConverted = winUnicodeToUtf8(zFilename);
  }
#ifdef SQLITE_WIN32_HAS_ANSI
  else{
    zConverted = sqlite3_win32_mbcs_to_utf8(zFilename);
  }
#endif
  /* caller will handle out of memory */
  return zConverted;
}
#endif

/*
** Convert a UTF-8 filename into whatever form the underlying
** operating system wants filenames in.  Space to hold the result
** is obtained from malloc and must be freed by the calling
** function.
*/
static void *winConvertFromUtf8Filename(const char *zFilename){
  void *zConverted = 0;
  if( osIsNT() ){
    zConverted = winUtf8ToUnicode(zFilename);
  }
#ifdef SQLITE_WIN32_HAS_ANSI
  else{
    zConverted = sqlite3_win32_utf8_to_mbcs(zFilename);
  }
#endif
  /* caller will handle out of memory */
  return zConverted;
}

/*
** This function returns non-zero if the specified UTF-8 string buffer
** ends with a directory separator character.

*/
static int winEndsInDirSep(char *zBuf){
  if( zBuf ){
    int nLen = sqlite3Strlen30(zBuf);
    return nLen>0 && winIsDirSep(zBuf[nLen-1]);
  }
  return 0;
}

/*
** Create a temporary file name and store the resulting pointer into pzBuf.

** The pointer returned in pzBuf must be freed via sqlite3_free().
*/

static int winGetTempname(sqlite3_vfs *pVfs, char **pzBuf){
  static char zChars[] =
    "abcdefghijklmnopqrstuvwxyz"
    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
    "0123456789";
  size_t i, j;
  int nBuf, nLen;
  char *zBuf;

  /* It's odd to simulate an io-error here, but really this is just
  ** using the io-error infrastructure to test that SQLite handles this
  ** function failing. 
  */
  SimulateIOError( return SQLITE_IOERR );

  /* Allocate a temporary buffer to store the fully qualified file
  ** name for the temporary file.  If this fails, we cannot continue.
  */
  nBuf = pVfs->mxPathname;
  zBuf = sqlite3MallocZero( nBuf+2 );
  if( !zBuf ){
    OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
    return SQLITE_IOERR_NOMEM;
  }

  /* Figure out the effective temporary directory.  First, check if one
  ** has been explicitly set by the application; otherwise, use the one
  ** configured by the operating system.
  */
  assert( nBuf>30 );
  if( sqlite3_temp_directory ){

    sqlite3_snprintf(nBuf-30, zBuf, "%s%s", sqlite3_temp_directory,
                     winEndsInDirSep(sqlite3_temp_directory) ? "" :
                     winGetDirDep());
  }
#if defined(__CYGWIN__)
  else{
    static const char *azDirs[] = {
       0, /* getenv("SQLITE_TMPDIR") */
       0, /* getenv("TMPDIR") */
       0, /* getenv("TMP") */
       0, /* getenv("TEMP") */
       0, /* getenv("USERPROFILE") */
       "/var/tmp",
       "/usr/tmp",
       "/tmp",
       ".",
       0        /* List terminator */
    };
    unsigned int i;
    const char *zDir = 0;

    if( !azDirs[0] ) azDirs[0] = getenv("SQLITE_TMPDIR");
    if( !azDirs[1] ) azDirs[1] = getenv("TMPDIR");
    if( !azDirs[2] ) azDirs[2] = getenv("TMP");
    if( !azDirs[3] ) azDirs[3] = getenv("TEMP");
    if( !azDirs[4] ) azDirs[4] = getenv("USERPROFILE");
    for(i=0; i<sizeof(azDirs)/sizeof(azDirs[0]); zDir=azDirs[i++]){
      void *zConverted;
      if( zDir==0 ) continue;
      /* If the path starts with a drive letter followed by the colon
      ** character, assume it is already a native Win32 path; otherwise,
      ** it must be converted to a native Win32 path prior via the Cygwin
      ** API prior to using it.
      */
      if( winIsDriveLetterAndColon(zDir) ){
        zConverted = winConvertFromUtf8Filename(zDir);
        if( !zConverted ){
          OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
          return SQLITE_IOERR_NOMEM;
        }
        if( winIsDir(zConverted) ){
          sqlite3_snprintf(nBuf-30, zBuf, "%s", zDir);
          sqlite3_free(zConverted);
          break;
        }
        sqlite3_free(zConverted);
      }else{
        zConverted = sqlite3MallocZero( nBuf+1 );
        if( !zConverted ){
          OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
          return SQLITE_IOERR_NOMEM;
        }
        if( cygwin_conv_path(
                osIsNT() ? CCP_POSIX_TO_WIN_W : CCP_POSIX_TO_WIN_A, zDir,
                zConverted, nBuf+1)<0 ){
          sqlite3_free(zConverted);
          OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_CONVPATH\n"));
          return winLogError(SQLITE_IOERR_CONVPATH, (DWORD)errno,
                             "winGetTempname1", zDir);
        }
        if( winIsDir(zConverted) ){
          /* At this point, we know the candidate directory exists and should
          ** be used.  However, we may need to convert the string containing
          ** its name into UTF-8 (i.e. if it is UTF-16 right now).
          */
          if( osIsNT() ){
            char *zUtf8 = winUnicodeToUtf8(zConverted);
            if( !zUtf8 ){
              sqlite3_free(zConverted);
              OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
              return SQLITE_IOERR_NOMEM;
            }
            sqlite3_snprintf(nBuf-30, zBuf, "%s", zUtf8);
            sqlite3_free(zUtf8);
            sqlite3_free(zConverted);
            break;
          }else{
            sqlite3_snprintf(nBuf-30, zBuf, "%s", zConverted);
            sqlite3_free(zConverted);
            break;
          }
        }
        sqlite3_free(zConverted);
      }
      break;
    }
  }
#elif !SQLITE_OS_WINRT && !defined(__CYGWIN__)
  else if( osIsNT() ){
    char *zMulti;
    LPWSTR zWidePath = sqlite3MallocZero( nBuf*sizeof(WCHAR) );
    if( !zWidePath ){
      sqlite3_free(zBuf);
      OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
      return SQLITE_IOERR_NOMEM;
    }
    if( osGetTempPathW(nBuf, zWidePath)==0 ){
      sqlite3_free(zWidePath);
      sqlite3_free(zBuf);
      OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_GETTEMPPATH\n"));
      return winLogError(SQLITE_IOERR_GETTEMPPATH, osGetLastError(),
                         "winGetTempname1", 0);
    }
    zMulti = winUnicodeToUtf8(zWidePath);
    if( zMulti ){

      sqlite3_snprintf(nBuf-30, zBuf, "%s", zMulti);
      sqlite3_free(zMulti);
      sqlite3_free(zWidePath);
    }else{
      sqlite3_free(zWidePath);
      sqlite3_free(zBuf);
      OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
      return SQLITE_IOERR_NOMEM;
    }
  }
#ifdef SQLITE_WIN32_HAS_ANSI
  else{
    char *zUtf8;
    char *zMbcsPath = sqlite3MallocZero( nBuf );
    if( !zMbcsPath ){
      sqlite3_free(zBuf);
      OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
      return SQLITE_IOERR_NOMEM;
    }
    if( osGetTempPathA(nBuf, zMbcsPath)==0 ){
      sqlite3_free(zBuf);
      OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_GETTEMPPATH\n"));
      return winLogError(SQLITE_IOERR_GETTEMPPATH, osGetLastError(),
                         "winGetTempname2", 0);
    }
    zUtf8 = sqlite3_win32_mbcs_to_utf8(zMbcsPath);
    if( zUtf8 ){
      sqlite3_snprintf(nBuf-30, zBuf, "%s", zUtf8);
      sqlite3_free(zUtf8);
    }else{
      sqlite3_free(zBuf);
      OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
      return SQLITE_IOERR_NOMEM;
    }
  }








#endif /* SQLITE_WIN32_HAS_ANSI */








#endif /* !SQLITE_OS_WINRT */

  /* Check that the output buffer is large enough for the temporary file 
  ** name. If it is not, return SQLITE_ERROR.
  */
  nLen = sqlite3Strlen30(zBuf);

  if( (nLen + sqlite3Strlen30(SQLITE_TEMP_FILE_PREFIX) + 18) >= nBuf ){
    sqlite3_free(zBuf);
    OSTRACE(("TEMP-FILENAME rc=SQLITE_ERROR\n"));

    return winLogError(SQLITE_ERROR, 0, "winGetTempname3", 0);
  }


  sqlite3_snprintf(nBuf-18-nLen, zBuf+nLen, SQLITE_TEMP_FILE_PREFIX);




  j = sqlite3Strlen30(zBuf);
  sqlite3_randomness(15, &zBuf[j]);
  for(i=0; i<15; i++, j++){
    zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
  }
  zBuf[j] = 0;
  zBuf[j+1] = 0;
  *pzBuf = zBuf;

  OSTRACE(("TEMP-FILENAME name=%s, rc=SQLITE_OK\n", zBuf));
  return SQLITE_OK;
}

/*
** Return TRUE if the named file is really a directory.  Return false if
................................................................................
** allocation failure.
*/
static int winIsDir(const void *zConverted){
  DWORD attr;
  int rc = 0;
  DWORD lastErrno;

  if( osIsNT() ){
    int cnt = 0;
    WIN32_FILE_ATTRIBUTE_DATA sAttrData;
    memset(&sAttrData, 0, sizeof(sAttrData));
    while( !(rc = osGetFileAttributesExW((LPCWSTR)zConverted,
                             GetFileExInfoStandard,
                             &sAttrData)) && winRetryIoerr(&cnt, &lastErrno) ){}
    if( !rc ){
      return 0; /* Invalid name? */
    }
    attr = sAttrData.dwFileAttributes;
#if SQLITE_OS_WINCE==0
  }else{
    attr = osGetFileAttributesA((char*)zConverted);
................................................................................
  return (attr!=INVALID_FILE_ATTRIBUTES) && (attr&FILE_ATTRIBUTE_DIRECTORY);
}

/*
** Open a file.
*/
static int winOpen(
  sqlite3_vfs *pVfs,        /* Used to get maximum path name length */
  const char *zName,        /* Name of the file (UTF-8) */
  sqlite3_file *id,         /* Write the SQLite file handle here */
  int flags,                /* Open mode flags */
  int *pOutFlags            /* Status return flags */
){
  HANDLE h;
  DWORD lastErrno;
................................................................................
  void *zConverted;              /* Filename in OS encoding */
  const char *zUtf8Name = zName; /* Filename in UTF-8 encoding */
  int cnt = 0;

  /* If argument zPath is a NULL pointer, this function is required to open
  ** a temporary file. Use this buffer to store the file name in.
  */
  char *zTmpname = 0; /* For temporary filename, if necessary. */

  int rc = SQLITE_OK;            /* Function Return Code */
#if !defined(NDEBUG) || SQLITE_OS_WINCE
  int eType = flags&0xFFFFFF00;  /* Type of file to open */
#endif

  int isExclusive  = (flags & SQLITE_OPEN_EXCLUSIVE);
................................................................................
  );

  assert( pFile!=0 );
  memset(pFile, 0, sizeof(winFile));
  pFile->h = INVALID_HANDLE_VALUE;

#if SQLITE_OS_WINRT
  if( !zUtf8Name && !sqlite3_temp_directory ){
    sqlite3_log(SQLITE_ERROR,
        "sqlite3_temp_directory variable should be set for WinRT");
  }
#endif

  /* If the second argument to this function is NULL, generate a 
  ** temporary file name to use 
  */
  if( !zUtf8Name ){
    assert( isDelete && !isOpenJournal );
    rc = winGetTempname(pVfs, &zTmpname);
    if( rc!=SQLITE_OK ){
      OSTRACE(("OPEN name=%s, rc=%s", zUtf8Name, sqlite3ErrName(rc)));
      return rc;
    }
    zUtf8Name = zTmpname;
  }

  /* Database filenames are double-zero terminated if they are not
  ** URIs with parameters.  Hence, they can always be passed into
  ** sqlite3_uri_parameter().
  */
  assert( (eType!=SQLITE_OPEN_MAIN_DB) || (flags & SQLITE_OPEN_URI) ||
       zUtf8Name[sqlite3Strlen30(zUtf8Name)+1]==0 );

  /* Convert the filename to the system encoding. */
  zConverted = winConvertFromUtf8Filename(zUtf8Name);
  if( zConverted==0 ){
    sqlite3_free(zTmpname);
    OSTRACE(("OPEN name=%s, rc=SQLITE_IOERR_NOMEM", zUtf8Name));
    return SQLITE_IOERR_NOMEM;
  }

  if( winIsDir(zConverted) ){
    sqlite3_free(zConverted);
    sqlite3_free(zTmpname);
    OSTRACE(("OPEN name=%s, rc=SQLITE_CANTOPEN_ISDIR", zUtf8Name));
    return SQLITE_CANTOPEN_ISDIR;
  }

  if( isReadWrite ){
    dwDesiredAccess = GENERIC_READ | GENERIC_WRITE;
  }else{
................................................................................
  }
  /* Reports from the internet are that performance is always
  ** better if FILE_FLAG_RANDOM_ACCESS is used.  Ticket #2699. */
#if SQLITE_OS_WINCE
  dwFlagsAndAttributes |= FILE_FLAG_RANDOM_ACCESS;
#endif

  if( osIsNT() ){
#if SQLITE_OS_WINRT
    CREATEFILE2_EXTENDED_PARAMETERS extendedParameters;
    extendedParameters.dwSize = sizeof(CREATEFILE2_EXTENDED_PARAMETERS);
    extendedParameters.dwFileAttributes =
            dwFlagsAndAttributes & FILE_ATTRIBUTE_MASK;
    extendedParameters.dwFileFlags = dwFlagsAndAttributes & FILE_FLAG_MASK;
    extendedParameters.dwSecurityQosFlags = SECURITY_ANONYMOUS;
................................................................................
    extendedParameters.lpSecurityAttributes = NULL;
    extendedParameters.hTemplateFile = NULL;
    while( (h = osCreateFile2((LPCWSTR)zConverted,
                              dwDesiredAccess,
                              dwShareMode,
                              dwCreationDisposition,
                              &extendedParameters))==INVALID_HANDLE_VALUE &&
                              winRetryIoerr(&cnt, &lastErrno) ){
               /* Noop */
    }
#else
    while( (h = osCreateFileW((LPCWSTR)zConverted,
                              dwDesiredAccess,
                              dwShareMode, NULL,
                              dwCreationDisposition,
                              dwFlagsAndAttributes,
                              NULL))==INVALID_HANDLE_VALUE &&
                              winRetryIoerr(&cnt, &lastErrno) ){
               /* Noop */
    }
#endif
  }
#ifdef SQLITE_WIN32_HAS_ANSI
  else{
    while( (h = osCreateFileA((LPCSTR)zConverted,
                              dwDesiredAccess,
                              dwShareMode, NULL,
                              dwCreationDisposition,
                              dwFlagsAndAttributes,
                              NULL))==INVALID_HANDLE_VALUE &&
                              winRetryIoerr(&cnt, &lastErrno) ){
               /* Noop */
    }
  }
#endif
  winLogIoerr(cnt);

  OSTRACE(("OPEN file=%p, name=%s, access=%lx, rc=%s\n", h, zUtf8Name,
           dwDesiredAccess, (h==INVALID_HANDLE_VALUE) ? "failed" : "ok"));

  if( h==INVALID_HANDLE_VALUE ){
    pFile->lastErrno = lastErrno;
    winLogError(SQLITE_CANTOPEN, pFile->lastErrno, "winOpen", zUtf8Name);
    sqlite3_free(zConverted);
    sqlite3_free(zTmpname);
    if( isReadWrite && !isExclusive ){
      return winOpen(pVfs, zName, id, 
         ((flags|SQLITE_OPEN_READONLY) &
                     ~(SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE)),
         pOutFlags);
    }else{
      return SQLITE_CANTOPEN_BKPT;
................................................................................

#if SQLITE_OS_WINCE
  if( isReadWrite && eType==SQLITE_OPEN_MAIN_DB
       && (rc = winceCreateLock(zName, pFile))!=SQLITE_OK
  ){
    osCloseHandle(h);
    sqlite3_free(zConverted);
    sqlite3_free(zTmpname);
    OSTRACE(("OPEN-CE-LOCK name=%s, rc=%s\n", zName, sqlite3ErrName(rc)));
    return rc;
  }
  if( isTemp ){
    pFile->zDeleteOnClose = zConverted;
  }else
#endif
  {
    sqlite3_free(zConverted);
    sqlite3_free(zTmpname);
  }

  pFile->pMethod = &winIoMethod;
  pFile->pVfs = pVfs;
  pFile->h = h;
  if( isReadonly ){
    pFile->ctrlFlags |= WINFILE_RDONLY;
................................................................................
  void *zConverted;
  UNUSED_PARAMETER(pVfs);
  UNUSED_PARAMETER(syncDir);

  SimulateIOError(return SQLITE_IOERR_DELETE);
  OSTRACE(("DELETE name=%s, syncDir=%d\n", zFilename, syncDir));

  zConverted = winConvertFromUtf8Filename(zFilename);
  if( zConverted==0 ){
    OSTRACE(("DELETE name=%s, rc=SQLITE_IOERR_NOMEM\n", zFilename));
    return SQLITE_IOERR_NOMEM;
  }
  if( osIsNT() ){
    do {
#if SQLITE_OS_WINRT
      WIN32_FILE_ATTRIBUTE_DATA sAttrData;
      memset(&sAttrData, 0, sizeof(sAttrData));
      if ( osGetFileAttributesExW(zConverted, GetFileExInfoStandard,
                                  &sAttrData) ){
        attr = sAttrData.dwFileAttributes;
................................................................................
        rc = SQLITE_ERROR; /* Files only. */
        break;
      }
      if ( osDeleteFileW(zConverted) ){
        rc = SQLITE_OK; /* Deleted OK. */
        break;
      }
      if ( !winRetryIoerr(&cnt, &lastErrno) ){
        rc = SQLITE_ERROR; /* No more retries. */
        break;
      }
    } while(1);
  }
#ifdef SQLITE_WIN32_HAS_ANSI
  else{
................................................................................
        rc = SQLITE_ERROR; /* Files only. */
        break;
      }
      if ( osDeleteFileA(zConverted) ){
        rc = SQLITE_OK; /* Deleted OK. */
        break;
      }
      if ( !winRetryIoerr(&cnt, &lastErrno) ){
        rc = SQLITE_ERROR; /* No more retries. */
        break;
      }
    } while(1);
  }
#endif
  if( rc && rc!=SQLITE_IOERR_DELETE_NOENT ){
    rc = winLogError(SQLITE_IOERR_DELETE, lastErrno, "winDelete", zFilename);

  }else{
    winLogIoerr(cnt);
  }
  sqlite3_free(zConverted);
  OSTRACE(("DELETE name=%s, rc=%s\n", zFilename, sqlite3ErrName(rc)));
  return rc;
}

/*
................................................................................
  void *zConverted;
  UNUSED_PARAMETER(pVfs);

  SimulateIOError( return SQLITE_IOERR_ACCESS; );
  OSTRACE(("ACCESS name=%s, flags=%x, pResOut=%p\n",
           zFilename, flags, pResOut));

  zConverted = winConvertFromUtf8Filename(zFilename);
  if( zConverted==0 ){
    OSTRACE(("ACCESS name=%s, rc=SQLITE_IOERR_NOMEM\n", zFilename));
    return SQLITE_IOERR_NOMEM;
  }
  if( osIsNT() ){
    int cnt = 0;
    WIN32_FILE_ATTRIBUTE_DATA sAttrData;
    memset(&sAttrData, 0, sizeof(sAttrData));
    while( !(rc = osGetFileAttributesExW((LPCWSTR)zConverted,
                             GetFileExInfoStandard, 
                             &sAttrData)) && winRetryIoerr(&cnt, &lastErrno) ){}
    if( rc ){
      /* For an SQLITE_ACCESS_EXISTS query, treat a zero-length file
      ** as if it does not exist.
      */
      if(    flags==SQLITE_ACCESS_EXISTS
          && sAttrData.nFileSizeHigh==0 
          && sAttrData.nFileSizeLow==0 ){
        attr = INVALID_FILE_ATTRIBUTES;
      }else{
        attr = sAttrData.dwFileAttributes;
      }
    }else{
      winLogIoerr(cnt);
      if( lastErrno!=ERROR_FILE_NOT_FOUND && lastErrno!=ERROR_PATH_NOT_FOUND ){

        sqlite3_free(zConverted);
        return winLogError(SQLITE_IOERR_ACCESS, lastErrno, "winAccess",
                           zFilename);
      }else{
        attr = INVALID_FILE_ATTRIBUTES;
      }
    }
  }
#ifdef SQLITE_WIN32_HAS_ANSI
  else{
................................................................................
  }
  *pResOut = rc;
  OSTRACE(("ACCESS name=%s, pResOut=%p, *pResOut=%d, rc=SQLITE_OK\n",
           zFilename, pResOut, *pResOut));
  return SQLITE_OK;
}

/*
** Returns non-zero if the specified path name starts with a drive letter
** followed by a colon character.
*/
static BOOL winIsDriveLetterAndColon(
  const char *zPathname
){
  return ( sqlite3Isalpha(zPathname[0]) && zPathname[1]==':' );
}

/*
** Returns non-zero if the specified path name should be used verbatim.  If
** non-zero is returned from this function, the calling function must simply
** use the provided path name verbatim -OR- resolve it into a full path name
** using the GetFullPathName Win32 API function (if available).
*/
................................................................................
  /*
  ** If the path name starts with a forward slash or a backslash, it is either
  ** a legal UNC name, a volume relative path, or an absolute path name in the
  ** "Unix" format on Windows.  There is no easy way to differentiate between
  ** the final two cases; therefore, we return the safer return value of TRUE
  ** so that callers of this function will simply use it verbatim.
  */
  if ( winIsDirSep(zPathname[0]) ){
    return TRUE;
  }

  /*
  ** If the path name starts with a letter and a colon it is either a volume
  ** relative path or an absolute path.  Callers of this function must not
  ** attempt to treat it as a relative path name (i.e. they should simply use
  ** it verbatim).
  */
  if ( winIsDriveLetterAndColon(zPathname) ){
    return TRUE;
  }

  /*
  ** If we get to this point, the path name should almost certainly be a purely
  ** relative one (i.e. not a UNC name, not absolute, and not volume relative).
  */
................................................................................
  int nFull,                    /* Size of output buffer in bytes */
  char *zFull                   /* Output buffer */
){
  
#if defined(__CYGWIN__)
  SimulateIOError( return SQLITE_ERROR );
  UNUSED_PARAMETER(nFull);

  assert( nFull>=pVfs->mxPathname );
  if ( sqlite3_data_directory && !winIsVerbatimPathname(zRelative) ){
    /*
    ** NOTE: We are dealing with a relative path name and the data
    **       directory has been set.  Therefore, use it as the basis
    **       for converting the relative path name to an absolute
    **       one by prepending the data directory and a slash.
    */
    char *zOut = sqlite3MallocZero( pVfs->mxPathname+1 );
    if( !zOut ){
      return SQLITE_IOERR_NOMEM;
    }
    if( cygwin_conv_path(CCP_POSIX_TO_WIN_A|CCP_RELATIVE, zRelative, zOut,

                         pVfs->mxPathname+1)<0 ){
      sqlite3_free(zOut);
      return winLogError(SQLITE_CANTOPEN_CONVPATH, (DWORD)errno,
                         "winFullPathname1", zRelative);

    }
    sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s%s%s",
                     sqlite3_data_directory, winGetDirDep(), zOut);
    sqlite3_free(zOut);
  }else{
    if( cygwin_conv_path(CCP_POSIX_TO_WIN_A, zRelative, zFull, nFull)<0 ){
      return winLogError(SQLITE_CANTOPEN_CONVPATH, (DWORD)errno,
                         "winFullPathname2", zRelative);

    }
  }
  return SQLITE_OK;
#endif

#if (SQLITE_OS_WINCE || SQLITE_OS_WINRT) && !defined(__CYGWIN__)
  SimulateIOError( return SQLITE_ERROR );
................................................................................
  if ( sqlite3_data_directory && !winIsVerbatimPathname(zRelative) ){
    /*
    ** NOTE: We are dealing with a relative path name and the data
    **       directory has been set.  Therefore, use it as the basis
    **       for converting the relative path name to an absolute
    **       one by prepending the data directory and a backslash.
    */
    sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s%s%s",
                     sqlite3_data_directory, winGetDirDep(), zRelative);
  }else{
    sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s", zRelative);
  }
  return SQLITE_OK;
#endif

#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && !defined(__CYGWIN__)
................................................................................
  DWORD nByte;
  void *zConverted;
  char *zOut;

  /* If this path name begins with "/X:", where "X" is any alphabetic
  ** character, discard the initial "/" from the pathname.
  */
  if( zRelative[0]=='/' && winIsDriveLetterAndColon(zRelative+1) ){
    zRelative++;
  }

  /* It's odd to simulate an io-error here, but really this is just
  ** using the io-error infrastructure to test that SQLite handles this
  ** function failing. This function could fail if, for example, the
  ** current working directory has been unlinked.
................................................................................
  if ( sqlite3_data_directory && !winIsVerbatimPathname(zRelative) ){
    /*
    ** NOTE: We are dealing with a relative path name and the data
    **       directory has been set.  Therefore, use it as the basis
    **       for converting the relative path name to an absolute
    **       one by prepending the data directory and a backslash.
    */
    sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s%s%s",
                     sqlite3_data_directory, winGetDirDep(), zRelative);
    return SQLITE_OK;
  }
  zConverted = winConvertFromUtf8Filename(zRelative);
  if( zConverted==0 ){
    return SQLITE_IOERR_NOMEM;
  }
  if( osIsNT() ){
    LPWSTR zTemp;
    nByte = osGetFullPathNameW((LPCWSTR)zConverted, 0, 0, 0);
    if( nByte==0 ){


      sqlite3_free(zConverted);
      return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
                         "winFullPathname1", zRelative);
    }
    nByte += 3;
    zTemp = sqlite3MallocZero( nByte*sizeof(zTemp[0]) );
    if( zTemp==0 ){
      sqlite3_free(zConverted);
      return SQLITE_IOERR_NOMEM;
    }
    nByte = osGetFullPathNameW((LPCWSTR)zConverted, nByte, zTemp, 0);
    if( nByte==0 ){


      sqlite3_free(zConverted);
      sqlite3_free(zTemp);
      return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
                         "winFullPathname2", zRelative);
    }
    sqlite3_free(zConverted);
    zOut = winUnicodeToUtf8(zTemp);
    sqlite3_free(zTemp);
  }
#ifdef SQLITE_WIN32_HAS_ANSI
  else{
    char *zTemp;
    nByte = osGetFullPathNameA((char*)zConverted, 0, 0, 0);
    if( nByte==0 ){


      sqlite3_free(zConverted);
      return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
                         "winFullPathname3", zRelative);
    }
    nByte += 3;
    zTemp = sqlite3MallocZero( nByte*sizeof(zTemp[0]) );
    if( zTemp==0 ){
      sqlite3_free(zConverted);
      return SQLITE_IOERR_NOMEM;
    }
    nByte = osGetFullPathNameA((char*)zConverted, nByte, zTemp, 0);
    if( nByte==0 ){


      sqlite3_free(zConverted);
      sqlite3_free(zTemp);
      return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
                         "winFullPathname4", zRelative);
    }
    sqlite3_free(zConverted);
    zOut = sqlite3_win32_mbcs_to_utf8(zTemp);
    sqlite3_free(zTemp);
  }
#endif
  if( zOut ){
................................................................................
*/
/*
** Interfaces for opening a shared library, finding entry points
** within the shared library, and closing the shared library.
*/
static void *winDlOpen(sqlite3_vfs *pVfs, const char *zFilename){
  HANDLE h;
  void *zConverted = winConvertFromUtf8Filename(zFilename);
  UNUSED_PARAMETER(pVfs);
  if( zConverted==0 ){
    return 0;
  }
  if( osIsNT() ){
#if SQLITE_OS_WINRT
    h = osLoadPackagedLibrary((LPCWSTR)zConverted, 0);
#else
    h = osLoadLibraryW((LPCWSTR)zConverted);
#endif
  }
#ifdef SQLITE_WIN32_HAS_ANSI
................................................................................
  }
#endif
  sqlite3_free(zConverted);
  return (void*)h;
}
static void winDlError(sqlite3_vfs *pVfs, int nBuf, char *zBufOut){
  UNUSED_PARAMETER(pVfs);
  winGetLastErrorMsg(osGetLastError(), nBuf, zBufOut);
}
static void (*winDlSym(sqlite3_vfs *pVfs,void *pH,const char *zSym))(void){
  UNUSED_PARAMETER(pVfs);
  return (void(*)(void))osGetProcAddressA((HANDLE)pH, zSym);
}
static void winDlClose(sqlite3_vfs *pVfs, void *pHandle){
  UNUSED_PARAMETER(pVfs);
................................................................................
**
** However if an error message is supplied, it will be incorporated
** by sqlite into the error message available to the user using
** sqlite3_errmsg(), possibly making IO errors easier to debug.
*/
static int winGetLastError(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
  UNUSED_PARAMETER(pVfs);
  return winGetLastErrorMsg(osGetLastError(), nBuf, zBuf);
}

/*
** Initialize and deinitialize the operating system interface.
*/
SQLITE_API int sqlite3_os_init(void){
  static sqlite3_vfs winVfs = {
    3,                   /* iVersion */
    sizeof(winFile),     /* szOsFile */
    SQLITE_WIN32_MAX_PATH_BYTES, /* mxPathname */
    0,                   /* pNext */
    "win32",             /* zName */
    0,                   /* pAppData */
    winOpen,             /* xOpen */
    winDelete,           /* xDelete */
    winAccess,           /* xAccess */
    winFullPathname,     /* xFullPathname */
................................................................................
    winCurrentTime,      /* xCurrentTime */
    winGetLastError,     /* xGetLastError */
    winCurrentTimeInt64, /* xCurrentTimeInt64 */
    winSetSystemCall,    /* xSetSystemCall */
    winGetSystemCall,    /* xGetSystemCall */
    winNextSystemCall,   /* xNextSystemCall */
  };
#if defined(SQLITE_WIN32_HAS_WIDE)
  static sqlite3_vfs winLongPathVfs = {
    3,                   /* iVersion */
    sizeof(winFile),     /* szOsFile */
    SQLITE_WINNT_MAX_PATH_BYTES, /* mxPathname */
    0,                   /* pNext */
    "win32-longpath",    /* zName */
    0,                   /* pAppData */
    winOpen,             /* xOpen */
    winDelete,           /* xDelete */
    winAccess,           /* xAccess */
    winFullPathname,     /* xFullPathname */
    winDlOpen,           /* xDlOpen */
    winDlError,          /* xDlError */
    winDlSym,            /* xDlSym */
    winDlClose,          /* xDlClose */
    winRandomness,       /* xRandomness */
    winSleep,            /* xSleep */
    winCurrentTime,      /* xCurrentTime */
    winGetLastError,     /* xGetLastError */
    winCurrentTimeInt64, /* xCurrentTimeInt64 */
    winSetSystemCall,    /* xSetSystemCall */
    winGetSystemCall,    /* xGetSystemCall */
    winNextSystemCall,   /* xNextSystemCall */
  };
#endif

  /* Double-check that the aSyscall[] array has been constructed
  ** correctly.  See ticket [bb3a86e890c8e96ab] */
  assert( ArraySize(aSyscall)==75 );

  /* get memory map allocation granularity */
  memset(&winSysInfo, 0, sizeof(SYSTEM_INFO));
#if SQLITE_OS_WINRT
  osGetNativeSystemInfo(&winSysInfo);
#else
  osGetSystemInfo(&winSysInfo);
#endif
  assert( winSysInfo.dwAllocationGranularity>0 );
  assert( winSysInfo.dwPageSize>0 );

  sqlite3_vfs_register(&winVfs, 1);

#if defined(SQLITE_WIN32_HAS_WIDE)
  sqlite3_vfs_register(&winLongPathVfs, 0);
#endif

  return SQLITE_OK; 
}

SQLITE_API int sqlite3_os_end(void){ 
#if SQLITE_OS_WINRT
  if( sleepObj!=NULL ){
    osCloseHandle(sleepObj);
................................................................................
**
** The first page is always a btree page.  The first 100 bytes of the first
** page contain a special header (the "file header") that describes the file.
** The format of the file header is as follows:
**
**   OFFSET   SIZE    DESCRIPTION
**      0      16     Header string: "SQLite format 3\000"
**     16       2     Page size in bytes.  (1 means 65536)
**     18       1     File format write version
**     19       1     File format read version
**     20       1     Bytes of unused space at the end of each page
**     21       1     Max embedded payload fraction (must be 64)
**     22       1     Min embedded payload fraction (must be 32)
**     23       1     Min leaf payload fraction (must be 32)
**     24       4     File change counter
**     28       4     Reserved for future use
**     32       4     First freelist page
**     36       4     Number of freelist pages in the file
**     40      60     15 4-byte meta values passed to higher layers
**
**     40       4     Schema cookie
**     44       4     File format of schema layer
**     48       4     Size of page cache
**     52       4     Largest root-page (auto/incr_vacuum)
**     56       4     1=UTF-8 2=UTF16le 3=UTF16be
**     60       4     User version
**     64       4     Incremental vacuum mode
**     68       4     Application-ID
**     72      20     unused
**     92       4     The version-valid-for number
**     96       4     SQLITE_VERSION_NUMBER
**
** All of the integer values are big-endian (most significant byte first).
**
** The file change counter is incremented when the database is changed
** This counter allows other processes to know when the file has changed
** and thus when they need to flush their cache.
**
................................................................................
  /* If the btree is already in a write-transaction, or it
  ** is already in a read-transaction and a read-transaction
  ** is requested, this is a no-op.
  */
  if( p->inTrans==TRANS_WRITE || (p->inTrans==TRANS_READ && !wrflag) ){
    goto trans_begun;
  }
  assert( pBt->inTransaction==TRANS_WRITE || IfNotOmitAV(pBt->bDoTruncate)==0 );

  /* Write transactions are not possible on a read-only database */
  if( (pBt->btsFlags & BTS_READ_ONLY)!=0 && wrflag ){
    rc = SQLITE_READONLY;
    goto trans_begun;
  }

................................................................................
    p->type = SQLITE_NULL;
    p->db = db;
  }
  return p;
}

/*
** Context object passed by sqlite3Stat4ProbeSetValue() through to 
** valueNew(). See comments above valueNew() for details.
*/
struct ValueNewStat4Ctx {
  Parse *pParse;
  Index *pIdx;
  UnpackedRecord **ppRec;
  int iVal;
};

/*
** Allocate and return a pointer to a new sqlite3_value object. If
** the second argument to this function is NULL, the object is allocated
** by calling sqlite3ValueNew().
**






** Otherwise, if the second argument is non-zero, then this function is 
** being called indirectly by sqlite3Stat4ProbeSetValue(). If it has not
** already been allocated, allocate the UnpackedRecord structure that 
** that function will return to its caller here. Then return a pointer 
** an sqlite3_value within the UnpackedRecord.a[] array.
*/
static sqlite3_value *valueNew(sqlite3 *db, struct ValueNewStat4Ctx *p){
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
  if( p ){
    UnpackedRecord *pRec = p->ppRec[0];

    if( pRec==0 ){
      Index *pIdx = p->pIdx;      /* Index being probed */
      int nByte;                  /* Bytes of space to allocate */
      int i;                      /* Counter variable */
      int nCol = pIdx->nColumn+1; /* Number of index columns including rowid */
  
      nByte = sizeof(Mem) * nCol + sizeof(UnpackedRecord);
      pRec = (UnpackedRecord*)sqlite3DbMallocZero(db, nByte);
      if( pRec ){
        pRec->pKeyInfo = sqlite3IndexKeyinfo(p->pParse, pIdx);
        if( pRec->pKeyInfo ){
          assert( pRec->pKeyInfo->nField+1==nCol );
          pRec->pKeyInfo->enc = ENC(db);
          pRec->flags = UNPACKED_PREFIX_MATCH;
          pRec->aMem = (Mem *)&pRec[1];
          for(i=0; i<nCol; i++){
            pRec->aMem[i].flags = MEM_Null;
            pRec->aMem[i].type = SQLITE_NULL;
            pRec->aMem[i].db = db;
          }
        }else{
          sqlite3DbFree(db, pRec);
          pRec = 0;
        }
      }
      if( pRec==0 ) return 0;
      p->ppRec[0] = pRec;
    }
  
    pRec->nField = p->iVal+1;
    return &pRec->aMem[p->iVal];
  }
#else
  UNUSED_PARAMETER(p);
#endif /* defined(SQLITE_ENABLE_STAT3_OR_STAT4) */
  return sqlite3ValueNew(db);
}

/*
** Extract a value from the supplied expression in the manner described
** above sqlite3ValueFromExpr(). Allocate the sqlite3_value object
** using valueNew().
**
** If pCtx is NULL and an error occurs after the sqlite3_value object
** has been allocated, it is freed before returning. Or, if pCtx is not
** NULL, it is assumed that the caller will free any allocated object
** in all cases.
*/
static int valueFromExpr(
  sqlite3 *db,                    /* The database connection */
  Expr *pExpr,                    /* The expression to evaluate */
  u8 enc,                         /* Encoding to use */
  u8 affinity,                    /* Affinity to use */
  sqlite3_value **ppVal,          /* Write the new value here */
  struct ValueNewStat4Ctx *pCtx   /* Second argument for valueNew() */
){
  int op;
  char *zVal = 0;
  sqlite3_value *pVal = 0;
  int negInt = 1;
  const char *zNeg = "";
  int rc = SQLITE_OK;

  if( !pExpr ){
    *ppVal = 0;
    return SQLITE_OK;
  }
  op = pExpr->op;

  /* op can only be TK_REGISTER if we have compiled with SQLITE_ENABLE_STAT4.
  ** The ifdef here is to enable us to achieve 100% branch test coverage even
  ** when SQLITE_ENABLE_STAT4 is omitted.
  */
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
  if( op==TK_REGISTER ) op = pExpr->op2;
#else
  if( NEVER(op==TK_REGISTER) ) op = pExpr->op2;
#endif

  /* Handle negative integers in a single step.  This is needed in the
  ** case when the value is -9223372036854775808.
................................................................................
    pExpr = pExpr->pLeft;
    op = pExpr->op;
    negInt = -1;
    zNeg = "-";
  }

  if( op==TK_STRING || op==TK_FLOAT || op==TK_INTEGER ){
    pVal = valueNew(db, pCtx);
    if( pVal==0 ) goto no_mem;
    if( ExprHasProperty(pExpr, EP_IntValue) ){
      sqlite3VdbeMemSetInt64(pVal, (i64)pExpr->u.iValue*negInt);
    }else{
      zVal = sqlite3MPrintf(db, "%s%s", zNeg, pExpr->u.zToken);
      if( zVal==0 ) goto no_mem;
      sqlite3ValueSetStr(pVal, -1, zVal, SQLITE_UTF8, SQLITE_DYNAMIC);
................................................................................
    if( (op==TK_INTEGER || op==TK_FLOAT ) && affinity==SQLITE_AFF_NONE ){
      sqlite3ValueApplyAffinity(pVal, SQLITE_AFF_NUMERIC, SQLITE_UTF8);
    }else{
      sqlite3ValueApplyAffinity(pVal, affinity, SQLITE_UTF8);
    }
    if( pVal->flags & (MEM_Int|MEM_Real) ) pVal->flags &= ~MEM_Str;
    if( enc!=SQLITE_UTF8 ){
      rc = sqlite3VdbeChangeEncoding(pVal, enc);
    }
  }else if( op==TK_UMINUS ) {
    /* This branch happens for multiple negative signs.  Ex: -(-5) */
    if( SQLITE_OK==sqlite3ValueFromExpr(db,pExpr->pLeft,enc,affinity,&pVal) 
     && pVal!=0
    ){
      sqlite3VdbeMemNumerify(pVal);
      if( pVal->u.i==SMALLEST_INT64 ){
        pVal->flags &= MEM_Int;
        pVal->flags |= MEM_Real;
        pVal->r = (double)LARGEST_INT64;
      }else{
        pVal->u.i = -pVal->u.i;
      }
      pVal->r = -pVal->r;
      sqlite3ValueApplyAffinity(pVal, affinity, enc);
    }
  }else if( op==TK_NULL ){
    pVal = valueNew(db, pCtx);
    if( pVal==0 ) goto no_mem;
  }
#ifndef SQLITE_OMIT_BLOB_LITERAL
  else if( op==TK_BLOB ){
    int nVal;
    assert( pExpr->u.zToken[0]=='x' || pExpr->u.zToken[0]=='X' );
    assert( pExpr->u.zToken[1]=='\'' );
    pVal = valueNew(db, pCtx);
    if( !pVal ) goto no_mem;
    zVal = &pExpr->u.zToken[2];
    nVal = sqlite3Strlen30(zVal)-1;
    assert( zVal[nVal]=='\'' );
    sqlite3VdbeMemSetStr(pVal, sqlite3HexToBlob(db, zVal, nVal), nVal/2,
                         0, SQLITE_DYNAMIC);
  }
#endif

  if( pVal ){
    sqlite3VdbeMemStoreType(pVal);
  }
  *ppVal = pVal;
  return rc;

no_mem:
  db->mallocFailed = 1;
  sqlite3DbFree(db, zVal);
  assert( *ppVal==0 );
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
  if( pCtx==0 ) sqlite3ValueFree(pVal);

#else
  assert( pCtx==0 ); sqlite3ValueFree(pVal);
#endif
  return SQLITE_NOMEM;
}

/*
** Create a new sqlite3_value object, containing the value of pExpr.
**
** This only works for very simple expressions that consist of one constant
** token (i.e. "5", "5.1", "'a string'"). If the expression can
** be converted directly into a value, then the value is allocated and
** a pointer written to *ppVal. The caller is responsible for deallocating
** the value by passing it to sqlite3ValueFree() later on. If the expression
** cannot be converted to a value, then *ppVal is set to NULL.
*/
SQLITE_PRIVATE int sqlite3ValueFromExpr(
  sqlite3 *db,              /* The database connection */
  Expr *pExpr,              /* The expression to evaluate */
  u8 enc,                   /* Encoding to use */
  u8 affinity,              /* Affinity to use */
  sqlite3_value **ppVal     /* Write the new value here */
){
  return valueFromExpr(db, pExpr, enc, affinity, ppVal, 0);
}

#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
/*
** The implementation of the sqlite_record() function. This function accepts
** a single argument of any type. The return value is a formatted database 
** record (a blob) containing the argument value.
**
** This is used to convert the value stored in the 'sample' column of the
** sqlite_stat3 table to the record format SQLite uses internally.
*/
static void recordFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  const int file_format = 1;
  int iSerial;                    /* Serial type */
  int nSerial;                    /* Bytes of space for iSerial as varint */
  int nVal;                       /* Bytes of space required for argv[0] */
  int nRet;
  sqlite3 *db;
  u8 *aRet;

  UNUSED_PARAMETER( argc );
  iSerial = sqlite3VdbeSerialType(argv[0], file_format);
  nSerial = sqlite3VarintLen(iSerial);
  nVal = sqlite3VdbeSerialTypeLen(iSerial);
  db = sqlite3_context_db_handle(context);

  nRet = 1 + nSerial + nVal;
  aRet = sqlite3DbMallocRaw(db, nRet);
  if( aRet==0 ){
    sqlite3_result_error_nomem(context);
  }else{
    aRet[0] = nSerial+1;
    sqlite3PutVarint(&aRet[1], iSerial);
    sqlite3VdbeSerialPut(&aRet[1+nSerial], nVal, argv[0], file_format);
    sqlite3_result_blob(context, aRet, nRet, SQLITE_TRANSIENT);
    sqlite3DbFree(db, aRet);
  }
}

/*
** Register built-in functions used to help read ANALYZE data.
*/
SQLITE_PRIVATE void sqlite3AnalyzeFunctions(void){
  static SQLITE_WSD FuncDef aAnalyzeTableFuncs[] = {
    FUNCTION(sqlite_record,   1, 0, 0, recordFunc),
  };
  int i;
  FuncDefHash *pHash = &GLOBAL(FuncDefHash, sqlite3GlobalFunctions);
  FuncDef *aFunc = (FuncDef*)&GLOBAL(FuncDef, aAnalyzeTableFuncs);
  for(i=0; i<ArraySize(aAnalyzeTableFuncs); i++){
    sqlite3FuncDefInsert(pHash, &aFunc[i]);
  }
}

/*
** This function is used to allocate and populate UnpackedRecord 
** structures intended to be compared against sample index keys stored 
** in the sqlite_stat4 table.
**
** A single call to this function attempts to populates field iVal (leftmost 
** is 0 etc.) of the unpacked record with a value extracted from expression
** pExpr. Extraction of values is possible if:
**
**  * (pExpr==0). In this case the value is assumed to be an SQL NULL,
**
**  * The expression is a bound variable, and this is a reprepare, or
**
**  * The sqlite3ValueFromExpr() function is able to extract a value 
**    from the expression (i.e. the expression is a literal value).
**
** If a value can be extracted, the affinity passed as the 5th argument
** is applied to it before it is copied into the UnpackedRecord. Output
** parameter *pbOk is set to true if a value is extracted, or false 
** otherwise.
**
** When this function is called, *ppRec must either point to an object
** allocated by an earlier call to this function, or must be NULL. If it
** is NULL and a value can be successfully extracted, a new UnpackedRecord
** is allocated (and *ppRec set to point to it) before returning.
**
** Unless an error is encountered, SQLITE_OK is returned. It is not an
** error if a value cannot be extracted from pExpr. If an error does
** occur, an SQLite error code is returned.
*/
SQLITE_PRIVATE int sqlite3Stat4ProbeSetValue(
  Parse *pParse,                  /* Parse context */
  Index *pIdx,                    /* Index being probed */
  UnpackedRecord **ppRec,         /* IN/OUT: Probe record */
  Expr *pExpr,                    /* The expression to extract a value from */
  u8 affinity,                    /* Affinity to use */
  int iVal,                       /* Array element to populate */
  int *pbOk                       /* OUT: True if value was extracted */
){
  int rc = SQLITE_OK;
  sqlite3_value *pVal = 0;
  sqlite3 *db = pParse->db;


  struct ValueNewStat4Ctx alloc;
  alloc.pParse = pParse;
  alloc.pIdx = pIdx;
  alloc.ppRec = ppRec;
  alloc.iVal = iVal;

  /* Skip over any TK_COLLATE nodes */
  pExpr = sqlite3ExprSkipCollate(pExpr);

  if( !pExpr ){
    pVal = valueNew(db, &alloc);
    if( pVal ){
      sqlite3VdbeMemSetNull((Mem*)pVal);
      *pbOk = 1;
    }
  }else if( pExpr->op==TK_VARIABLE
        || (pExpr->op==TK_REGISTER && pExpr->op2==TK_VARIABLE)
  ){
    Vdbe *v;
    int iBindVar = pExpr->iColumn;
    sqlite3VdbeSetVarmask(pParse->pVdbe, iBindVar);
    if( (v = pParse->pReprepare)!=0 ){
      pVal = valueNew(db, &alloc);
      if( pVal ){
        rc = sqlite3VdbeMemCopy((Mem*)pVal, &v->aVar[iBindVar-1]);
        if( rc==SQLITE_OK ){
          sqlite3ValueApplyAffinity(pVal, affinity, ENC(db));
        }
        pVal->db = pParse->db;
        *pbOk = 1;
        sqlite3VdbeMemStoreType((Mem*)pVal);
      }
    }else{
      *pbOk = 0;
    }
  }else{
    rc = valueFromExpr(db, pExpr, ENC(db), affinity, &pVal, &alloc);
    *pbOk = (pVal!=0);
  }

  assert( pVal==0 || pVal->db==db );
  return rc;
}

/*
** Unless it is NULL, the argument must be an UnpackedRecord object returned
** by an earlier call to sqlite3Stat4ProbeSetValue(). This call deletes
** the object.
*/
SQLITE_PRIVATE void sqlite3Stat4ProbeFree(UnpackedRecord *pRec){
  if( pRec ){
    int i;
    int nCol = pRec->pKeyInfo->nField+1;
    Mem *aMem = pRec->aMem;
    sqlite3 *db = aMem[0].db;
    for(i=0; i<nCol; i++){
      sqlite3DbFree(db, aMem[i].zMalloc);
    }
    sqlite3DbFree(db, pRec->pKeyInfo);
    sqlite3DbFree(db, pRec);
  }
}
#endif /* ifdef SQLITE_ENABLE_STAT4 */

/*
** Change the string value of an sqlite3_value object
*/
SQLITE_PRIVATE void sqlite3ValueSetStr(
  sqlite3_value *v,     /* Value to be set */
  int n,                /* Length of string z */
  const void *z,        /* Text of the new string */
................................................................................


/*
** If the input FuncDef structure is ephemeral, then free it.  If
** the FuncDef is not ephermal, then do nothing.
*/
static void freeEphemeralFunction(sqlite3 *db, FuncDef *pDef){
  if( ALWAYS(pDef) && (pDef->funcFlags & SQLITE_FUNC_EPHEM)!=0 ){
    sqlite3DbFree(db, pDef);
  }
}

static void vdbeFreeOpArray(sqlite3 *, Op *, int);

/*
................................................................................
        );
        sqlite3VdbePrintOp(out, i, &p->aOp[i]);
      }
      fclose(out);
    }
  }
#endif
  p->iCurrentTime = 0;
  p->magic = VDBE_MAGIC_INIT;
  return p->rc & db->errMask;
}
 
/*
** Clean up and delete a VDBE after execution.  Return an integer which is
** the result code.  Write any error message text into *pzErrMsg.
................................................................................
      v->rc = rc = SQLITE_NOMEM;
    }
  }
  rc = sqlite3ApiExit(db, rc);
  sqlite3_mutex_leave(db->mutex);
  return rc;
}


/*
** Extract the user data from a sqlite3_context structure and return a
** pointer to it.
*/
SQLITE_API void *sqlite3_user_data(sqlite3_context *p){
  assert( p && p->pFunc );
................................................................................
** sqlite3_create_function16() routines that originally registered the
** application defined function.
*/
SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context *p){
  assert( p && p->pFunc );
  return p->s.db;
}

/*
** Return the current time for a statement
*/
SQLITE_PRIVATE sqlite3_int64 sqlite3StmtCurrentTime(sqlite3_context *p){
  Vdbe *v = p->pVdbe;
  int rc;
  if( v->iCurrentTime==0 ){
    rc = sqlite3OsCurrentTimeInt64(p->s.db->pVfs, &v->iCurrentTime);
    if( rc ) v->iCurrentTime = 0;
  }
  return v->iCurrentTime;
}

/*
** The following is the implementation of an SQL function that always
** fails with an error message stating that the function is used in the
** wrong context.  The sqlite3_overload_function() API might construct
** SQL function that use this routine so that the functions will exist
** for name resolution but are actually overloaded by the xFindFunction
................................................................................
    /* This happens if a malloc() inside a call to sqlite3_column_text() or
    ** sqlite3_column_text16() failed.  */
    goto no_mem;
  }
  assert( p->rc==SQLITE_OK || p->rc==SQLITE_BUSY );
  assert( p->bIsReader || p->readOnly!=0 );
  p->rc = SQLITE_OK;
  p->iCurrentTime = 0;
  assert( p->explain==0 );
  p->pResultSet = 0;
  db->busyHandler.nBusy = 0;
  CHECK_FOR_INTERRUPT;
  sqlite3VdbeIOTraceSql(p);
#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
  if( db->xProgress ){
................................................................................
    ** external allocations out of mem[p2] and set mem[p2] to be
    ** an undefined integer.  Opcodes will either fill in the integer
    ** value or convert mem[p2] to a different type.
    */
    assert( pOp->opflags==sqlite3OpcodeProperty[pOp->opcode] );
    if( pOp->opflags & OPFLG_OUT2_PRERELEASE ){
      assert( pOp->p2>0 );
      assert( pOp->p2<=(p->nMem-p->nCursor) );
      pOut = &aMem[pOp->p2];
      memAboutToChange(p, pOut);
      VdbeMemRelease(pOut);
      pOut->flags = MEM_Int;
    }

    /* Sanity checking on other operands */
#ifdef SQLITE_DEBUG
    if( (pOp->opflags & OPFLG_IN1)!=0 ){
      assert( pOp->p1>0 );
      assert( pOp->p1<=(p->nMem-p->nCursor) );
      assert( memIsValid(&aMem[pOp->p1]) );
      REGISTER_TRACE(pOp->p1, &aMem[pOp->p1]);
    }
    if( (pOp->opflags & OPFLG_IN2)!=0 ){
      assert( pOp->p2>0 );
      assert( pOp->p2<=(p->nMem-p->nCursor) );
      assert( memIsValid(&aMem[pOp->p2]) );
      REGISTER_TRACE(pOp->p2, &aMem[pOp->p2]);
    }
    if( (pOp->opflags & OPFLG_IN3)!=0 ){
      assert( pOp->p3>0 );
      assert( pOp->p3<=(p->nMem-p->nCursor) );
      assert( memIsValid(&aMem[pOp->p3]) );
      REGISTER_TRACE(pOp->p3, &aMem[pOp->p3]);
    }
    if( (pOp->opflags & OPFLG_OUT2)!=0 ){
      assert( pOp->p2>0 );
      assert( pOp->p2<=(p->nMem-p->nCursor) );
      memAboutToChange(p, &aMem[pOp->p2]);
    }
    if( (pOp->opflags & OPFLG_OUT3)!=0 ){
      assert( pOp->p3>0 );
      assert( pOp->p3<=(p->nMem-p->nCursor) );
      memAboutToChange(p, &aMem[pOp->p3]);
    }
#endif
  
    switch( pOp->opcode ){

/*****************************************************************************
................................................................................

/* Opcode:  Gosub P1 P2 * * *
**
** Write the current address onto register P1
** and then jump to address P2.
*/
case OP_Gosub: {            /* jump */
  assert( pOp->p1>0 && pOp->p1<=(p->nMem-p->nCursor) );
  pIn1 = &aMem[pOp->p1];
  assert( (pIn1->flags & MEM_Dyn)==0 );
  memAboutToChange(p, pIn1);
  pIn1->flags = MEM_Int;
  pIn1->u.i = pc;
  REGISTER_TRACE(pOp->p1, pIn1);
  pc = pOp->p2 - 1;
................................................................................
*/
case OP_Null: {           /* out2-prerelease */
#if 0  /* local variables moved into u.ab */
  int cnt;
  u16 nullFlag;
#endif /* local variables moved into u.ab */
  u.ab.cnt = pOp->p3-pOp->p2;
  assert( pOp->p3<=(p->nMem-p->nCursor) );
  pOut->flags = u.ab.nullFlag = pOp->p1 ? (MEM_Null|MEM_Cleared) : MEM_Null;
  while( u.ab.cnt>0 ){
    pOut++;
    memAboutToChange(p, pOut);
    VdbeMemRelease(pOut);
    pOut->flags = u.ab.nullFlag;
    u.ab.cnt--;
................................................................................
  u.ad.p2 = pOp->p2;
  assert( u.ad.n>0 && u.ad.p1>0 && u.ad.p2>0 );
  assert( u.ad.p1+u.ad.n<=u.ad.p2 || u.ad.p2+u.ad.n<=u.ad.p1 );

  pIn1 = &aMem[u.ad.p1];
  pOut = &aMem[u.ad.p2];
  while( u.ad.n-- ){
    assert( pOut<=&aMem[(p->nMem-p->nCursor)] );
    assert( pIn1<=&aMem[(p->nMem-p->nCursor)] );
    assert( memIsValid(pIn1) );
    memAboutToChange(p, pOut);
    u.ad.zMalloc = pOut->zMalloc;
    pOut->zMalloc = 0;
    sqlite3VdbeMemMove(pOut, pIn1);
#ifdef SQLITE_DEBUG
    if( pOut->pScopyFrom>=&aMem[u.ad.p1] && pOut->pScopyFrom<&aMem[u.ad.p1+pOp->p3] ){
................................................................................
case OP_ResultRow: {
#if 0  /* local variables moved into u.af */
  Mem *pMem;
  int i;
#endif /* local variables moved into u.af */
  assert( p->nResColumn==pOp->p2 );
  assert( pOp->p1>0 );
  assert( pOp->p1+pOp->p2<=(p->nMem-p->nCursor)+1 );

  /* If this statement has violated immediate foreign key constraints, do
  ** not return the number of rows modified. And do not RELEASE the statement
  ** transaction. It needs to be rolled back.  */
  if( SQLITE_OK!=(rc = sqlite3VdbeCheckFk(p, 0)) ){
    assert( db->flags&SQLITE_CountRows );
    assert( p->usesStmtJournal );
................................................................................
  sqlite3_value **apVal;
  int n;
#endif /* local variables moved into u.ai */

  u.ai.n = pOp->p5;
  u.ai.apVal = p->apArg;
  assert( u.ai.apVal || u.ai.n==0 );
  assert( pOp->p3>0 && pOp->p3<=(p->nMem-p->nCursor) );
  pOut = &aMem[pOp->p3];
  memAboutToChange(p, pOut);

  assert( u.ai.n==0 || (pOp->p2>0 && pOp->p2+u.ai.n<=(p->nMem-p->nCursor)+1) );
  assert( pOp->p3<pOp->p2 || pOp->p3>=pOp->p2+u.ai.n );
  u.ai.pArg = &aMem[pOp->p2];
  for(u.ai.i=0; u.ai.i<u.ai.n; u.ai.i++, u.ai.pArg++){
    assert( memIsValid(u.ai.pArg) );
    u.ai.apVal[u.ai.i] = u.ai.pArg;
    Deephemeralize(u.ai.pArg);
    sqlite3VdbeMemStoreType(u.ai.pArg);
................................................................................
  ** the pointer to u.ai.ctx.s so in case the user-function can use
  ** the already allocated buffer instead of allocating a new one.
  */
  sqlite3VdbeMemMove(&u.ai.ctx.s, pOut);
  MemSetTypeFlag(&u.ai.ctx.s, MEM_Null);

  u.ai.ctx.fErrorOrAux = 0;
  if( u.ai.ctx.pFunc->funcFlags & SQLITE_FUNC_NEEDCOLL ){
    assert( pOp>aOp );
    assert( pOp[-1].p4type==P4_COLLSEQ );
    assert( pOp[-1].opcode==OP_CollSeq );
    u.ai.ctx.pColl = pOp[-1].p4.pColl;
  }
  db->lastRowid = lastRowid;
  (*u.ai.ctx.pFunc->xFunc)(&u.ai.ctx, u.ai.n, u.ai.apVal); /* IMP: R-24505-23230 */
................................................................................
  assert( u.al.pKeyInfo!=0 );
  u.al.p1 = pOp->p1;
  u.al.p2 = pOp->p2;
#if SQLITE_DEBUG
  if( aPermute ){
    int k, mx = 0;
    for(k=0; k<u.al.n; k++) if( aPermute[k]>mx ) mx = aPermute[k];
    assert( u.al.p1>0 && u.al.p1+mx<=(p->nMem-p->nCursor)+1 );
    assert( u.al.p2>0 && u.al.p2+mx<=(p->nMem-p->nCursor)+1 );
  }else{
    assert( u.al.p1>0 && u.al.p1+u.al.n<=(p->nMem-p->nCursor)+1 );
    assert( u.al.p2>0 && u.al.p2+u.al.n<=(p->nMem-p->nCursor)+1 );
  }
#endif /* SQLITE_DEBUG */
  for(u.al.i=0; u.al.i<u.al.n; u.al.i++){
    u.al.idx = aPermute ? aPermute[u.al.i] : u.al.i;
    assert( memIsValid(&aMem[u.al.p1+u.al.idx]) );
    assert( memIsValid(&aMem[u.al.p2+u.al.idx]) );
    REGISTER_TRACE(u.al.p1+u.al.idx, &aMem[u.al.p1+u.al.idx]);
................................................................................


  u.ao.p1 = pOp->p1;
  u.ao.p2 = pOp->p2;
  u.ao.pC = 0;
  memset(&u.ao.sMem, 0, sizeof(u.ao.sMem));
  assert( u.ao.p1<p->nCursor );
  assert( pOp->p3>0 && pOp->p3<=(p->nMem-p->nCursor) );
  u.ao.pDest = &aMem[pOp->p3];
  memAboutToChange(p, u.ao.pDest);
  u.ao.zRec = 0;

  /* This block sets the variable u.ao.payloadSize to be the total number of
  ** bytes in the record.
  **
................................................................................
#endif /* local variables moved into u.ap */

  u.ap.zAffinity = pOp->p4.z;
  assert( u.ap.zAffinity!=0 );
  assert( u.ap.zAffinity[pOp->p2]==0 );
  pIn1 = &aMem[pOp->p1];
  while( (u.ap.cAff = *(u.ap.zAffinity++))!=0 ){
    assert( pIn1 <= &p->aMem[(p->nMem-p->nCursor)] );
    assert( memIsValid(pIn1) );
    ExpandBlob(pIn1);
    applyAffinity(pIn1, u.ap.cAff, encoding);
    pIn1++;
  }
  break;
}
................................................................................
  ** of the record to data0.
  */
  u.aq.nData = 0;         /* Number of bytes of data space */
  u.aq.nHdr = 0;          /* Number of bytes of header space */
  u.aq.nZero = 0;         /* Number of zero bytes at the end of the record */
  u.aq.nField = pOp->p1;
  u.aq.zAffinity = pOp->p4.z;
  assert( u.aq.nField>0 && pOp->p2>0 && pOp->p2+u.aq.nField<=(p->nMem-p->nCursor)+1 );
  u.aq.pData0 = &aMem[u.aq.nField];
  u.aq.nField = pOp->p2;
  u.aq.pLast = &u.aq.pData0[u.aq.nField-1];
  u.aq.file_format = p->minWriteFileFormat;

  /* Identify the output register */
  assert( pOp->p3<pOp->p1 || pOp->p3>=pOp->p1+pOp->p2 );
................................................................................
    u.aq.i += putVarint32(&u.aq.zNewRecord[u.aq.i], u.aq.serial_type);      /* serial type */
  }
  for(u.aq.pRec=u.aq.pData0; u.aq.pRec<=u.aq.pLast; u.aq.pRec++){  /* serial data */
    u.aq.i += sqlite3VdbeSerialPut(&u.aq.zNewRecord[u.aq.i], (int)(u.aq.nByte-u.aq.i), u.aq.pRec,u.aq.file_format);
  }
  assert( u.aq.i==u.aq.nByte );

  assert( pOp->p3>0 && pOp->p3<=(p->nMem-p->nCursor) );
  pOut->n = (int)u.aq.nByte;
  pOut->flags = MEM_Blob | MEM_Dyn;
  pOut->xDel = 0;
  if( u.aq.nZero ){
    pOut->u.nZero = u.aq.nZero;
    pOut->flags |= MEM_Zero;
  }
................................................................................
      p->minWriteFileFormat = u.ay.pDb->pSchema->file_format;
    }
  }else{
    u.ay.wrFlag = 0;
  }
  if( pOp->p5 & OPFLAG_P2ISREG ){
    assert( u.ay.p2>0 );
    assert( u.ay.p2<=(p->nMem-p->nCursor) );
    pIn2 = &aMem[u.ay.p2];
    assert( memIsValid(pIn2) );
    assert( (pIn2->flags & MEM_Int)!=0 );
    sqlite3VdbeMemIntegerify(pIn2);
    u.ay.p2 = (int)pIn2->u.i;
    /* The u.ay.p2 value always comes from a prior OP_CreateTable opcode and
    ** that opcode will always set the u.ay.p2 value to 2 or more or else fail.
................................................................................
  i64 R;                             /* Rowid stored in register P3 */
#endif /* local variables moved into u.bf */

  pIn3 = &aMem[pOp->p3];
  u.bf.aMx = &aMem[pOp->p4.i];
  /* Assert that the values of parameters P1 and P4 are in range. */
  assert( pOp->p4type==P4_INT32 );
  assert( pOp->p4.i>0 && pOp->p4.i<=(p->nMem-p->nCursor) );
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );

  /* Find the index cursor. */
  u.bf.pCx = p->apCsr[pOp->p1];
  assert( u.bf.pCx->deferredMoveto==0 );
  u.bf.pCx->seekResult = 0;
  u.bf.pCx->cacheStatus = CACHE_STALE;
................................................................................
        if( p->pFrame ){
          for(u.bh.pFrame=p->pFrame; u.bh.pFrame->pParent; u.bh.pFrame=u.bh.pFrame->pParent);
          /* Assert that P3 is a valid memory cell. */
          assert( pOp->p3<=u.bh.pFrame->nMem );
          u.bh.pMem = &u.bh.pFrame->aMem[pOp->p3];
        }else{
          /* Assert that P3 is a valid memory cell. */
          assert( pOp->p3<=(p->nMem-p->nCursor) );
          u.bh.pMem = &aMem[pOp->p3];
          memAboutToChange(p, u.bh.pMem);
        }
        assert( memIsValid(u.bh.pMem) );

        REGISTER_TRACE(pOp->p3, u.bh.pMem);
        sqlite3VdbeMemIntegerify(u.bh.pMem);
................................................................................
  VdbeCursor *pC;
  BtCursor *pCrsr;
  int res;
  UnpackedRecord r;
#endif /* local variables moved into u.bt */

  assert( pOp->p3>0 );
  assert( pOp->p2>0 && pOp->p2+pOp->p3<=(p->nMem-p->nCursor)+1 );
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  u.bt.pC = p->apCsr[pOp->p1];
  assert( u.bt.pC!=0 );
  u.bt.pCrsr = u.bt.pC->pCursor;
  if( ALWAYS(u.bt.pCrsr!=0) ){
    u.bt.r.pKeyInfo = u.bt.pC->pKeyInfo;
    u.bt.r.nField = (u16)pOp->p3;
................................................................................
case OP_Clear: {
#if 0  /* local variables moved into u.bx */
  int nChange;
#endif /* local variables moved into u.bx */

  u.bx.nChange = 0;
  assert( p->readOnly==0 );
  assert( pOp->p1!=1 );
  assert( (p->btreeMask & (((yDbMask)1)<<pOp->p2))!=0 );
  rc = sqlite3BtreeClearTable(
      db->aDb[pOp->p2].pBt, pOp->p1, (pOp->p3 ? &u.bx.nChange : 0)
  );
  if( pOp->p3 ){
    p->nChange += u.bx.nChange;
    if( pOp->p3>0 ){
................................................................................
#endif /* local variables moved into u.ca */

  assert( p->bIsReader );
  u.ca.nRoot = pOp->p2;
  assert( u.ca.nRoot>0 );
  u.ca.aRoot = sqlite3DbMallocRaw(db, sizeof(int)*(u.ca.nRoot+1) );
  if( u.ca.aRoot==0 ) goto no_mem;
  assert( pOp->p3>0 && pOp->p3<=(p->nMem-p->nCursor) );
  u.ca.pnErr = &aMem[pOp->p3];
  assert( (u.ca.pnErr->flags & MEM_Int)!=0 );
  assert( (u.ca.pnErr->flags & (MEM_Str|MEM_Blob))==0 );
  pIn1 = &aMem[pOp->p1];
  for(u.ca.j=0; u.ca.j<u.ca.nRoot; u.ca.j++){
    u.ca.aRoot[u.ca.j] = (int)sqlite3VdbeIntValue(&pIn1[u.ca.j]);
  }
................................................................................
  for(u.cg.i=0; u.cg.i<u.cg.n; u.cg.i++, u.cg.pRec++){
    assert( memIsValid(u.cg.pRec) );
    u.cg.apVal[u.cg.i] = u.cg.pRec;
    memAboutToChange(p, u.cg.pRec);
    sqlite3VdbeMemStoreType(u.cg.pRec);
  }
  u.cg.ctx.pFunc = pOp->p4.pFunc;
  assert( pOp->p3>0 && pOp->p3<=(p->nMem-p->nCursor) );
  u.cg.ctx.pMem = u.cg.pMem = &aMem[pOp->p3];
  u.cg.pMem->n++;
  u.cg.ctx.s.flags = MEM_Null;
  u.cg.ctx.s.z = 0;
  u.cg.ctx.s.zMalloc = 0;
  u.cg.ctx.s.xDel = 0;
  u.cg.ctx.s.db = db;
  u.cg.ctx.isError = 0;
  u.cg.ctx.pColl = 0;
  u.cg.ctx.skipFlag = 0;
  if( u.cg.ctx.pFunc->funcFlags & SQLITE_FUNC_NEEDCOLL ){
    assert( pOp>p->aOp );
    assert( pOp[-1].p4type==P4_COLLSEQ );
    assert( pOp[-1].opcode==OP_CollSeq );
    u.cg.ctx.pColl = pOp[-1].p4.pColl;
  }
  (u.cg.ctx.pFunc->xStep)(&u.cg.ctx, u.cg.n, u.cg.apVal); /* IMP: R-24505-23230 */
  if( u.cg.ctx.isError ){
................................................................................
** P4 argument is only needed for the degenerate case where
** the step function was not previously called.
*/
case OP_AggFinal: {
#if 0  /* local variables moved into u.ch */
  Mem *pMem;
#endif /* local variables moved into u.ch */
  assert( pOp->p1>0 && pOp->p1<=(p->nMem-p->nCursor) );
  u.ch.pMem = &aMem[pOp->p1];
  assert( (u.ch.pMem->flags & ~(MEM_Null|MEM_Agg))==0 );
  rc = sqlite3VdbeMemFinalize(u.ch.pMem, pOp->p4.pFunc);
  if( rc ){
    sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3_value_text(u.ch.pMem));
  }
  sqlite3VdbeChangeEncoding(u.ch.pMem, encoding);
................................................................................
  const sqlite3_module *pModule;
  Mem *pDest;
  sqlite3_context sContext;
#endif /* local variables moved into u.co */

  VdbeCursor *pCur = p->apCsr[pOp->p1];
  assert( pCur->pVtabCursor );
  assert( pOp->p3>0 && pOp->p3<=(p->nMem-p->nCursor) );
  u.co.pDest = &aMem[pOp->p3];
  memAboutToChange(p, u.co.pDest);
  if( pCur->nullRow ){
    sqlite3VdbeMemSetNull(u.co.pDest);
    break;
  }
  u.co.pVtab = pCur->pVtabCursor->pVtab;
................................................................................
SQLITE_PRIVATE int sqlite3WalkExpr(Walker *pWalker, Expr *pExpr){
  int rc;
  if( pExpr==0 ) return WRC_Continue;
  testcase( ExprHasProperty(pExpr, EP_TokenOnly) );
  testcase( ExprHasProperty(pExpr, EP_Reduced) );
  rc = pWalker->xExprCallback(pWalker, pExpr);
  if( rc==WRC_Continue
              && !ExprHasProperty(pExpr,EP_TokenOnly) ){
    if( sqlite3WalkExpr(pWalker, pExpr->pLeft) ) return WRC_Abort;
    if( sqlite3WalkExpr(pWalker, pExpr->pRight) ) return WRC_Abort;
    if( ExprHasProperty(pExpr, EP_xIsSelect) ){
      if( sqlite3WalkSelect(pWalker, pExpr->x.pSelect) ) return WRC_Abort;
    }else{
      if( sqlite3WalkExprList(pWalker, pExpr->x.pList) ) return WRC_Abort;
    }
................................................................................
  db = pParse->db;
  pDup = sqlite3ExprDup(db, pOrig, 0);
  if( pDup==0 ) return;
  if( pOrig->op!=TK_COLUMN && zType[0]!='G' ){
    incrAggFunctionDepth(pDup, nSubquery);
    pDup = sqlite3PExpr(pParse, TK_AS, pDup, 0, 0);
    if( pDup==0 ) return;
    ExprSetProperty(pDup, EP_Skip);
    if( pEList->a[iCol].iAlias==0 ){
      pEList->a[iCol].iAlias = (u16)(++pParse->nAlias);
    }
    pDup->iTable = pEList->a[iCol].iAlias;
  }
  if( pExpr->op==TK_COLLATE ){
    pDup = sqlite3ExprAddCollateString(pParse, pDup, pExpr->u.zToken);
................................................................................
  */
  ExprSetProperty(pExpr, EP_Static);
  sqlite3ExprDelete(db, pExpr);
  memcpy(pExpr, pDup, sizeof(*pExpr));
  if( !ExprHasProperty(pExpr, EP_IntValue) && pExpr->u.zToken!=0 ){
    assert( (pExpr->flags & (EP_Reduced|EP_TokenOnly))==0 );
    pExpr->u.zToken = sqlite3DbStrDup(db, pExpr->u.zToken);
    pExpr->flags |= EP_MemToken;
  }
  sqlite3DbFree(db, pDup);
}


/*
** Return TRUE if the name zCol occurs anywhere in the USING clause.
................................................................................
  struct SrcList_item *pMatch = 0;  /* The matching pSrcList item */
  NameContext *pTopNC = pNC;        /* First namecontext in the list */
  Schema *pSchema = 0;              /* Schema of the expression */
  int isTrigger = 0;

  assert( pNC );     /* the name context cannot be NULL. */
  assert( zCol );    /* The Z in X.Y.Z cannot be NULL */
  assert( !ExprHasProperty(pExpr, EP_TokenOnly|EP_Reduced) );

  /* Initialize the node to no-match */
  pExpr->iTable = -1;
  pExpr->pTab = 0;
  ExprSetVVAProperty(pExpr, EP_NoReduce);

  /* Translate the schema name in zDb into a pointer to the corresponding
  ** schema.  If not found, pSchema will remain NULL and nothing will match
  ** resulting in an appropriate error message toward the end of this routine
  */
  if( zDb ){
    testcase( pNC->ncFlags & NC_PartIdx );
................................................................................
    sqlite3ErrorMsg(pParse,"%s prohibited in CHECK constraints", zMsg);
  }
}
#else
# define notValidCheckConstraint(P,N,M)
#endif

/*
** Expression p should encode a floating point value between 1.0 and 0.0.
** Return 1024 times this value.  Or return -1 if p is not a floating point
** value between 1.0 and 0.0.
*/
static int exprProbability(Expr *p){
  double r = -1.0;
  if( p->op!=TK_FLOAT ) return -1;
  sqlite3AtoF(p->u.zToken, &r, sqlite3Strlen30(p->u.zToken), SQLITE_UTF8);
  assert( r>=0.0 );
  if( r>1.0 ) return -1;
  return (int)(r*1000.0);
}

/*
** This routine is callback for sqlite3WalkExpr().
**
** Resolve symbolic names into TK_COLUMN operators for the current
** node in the expression tree.  Return 0 to continue the search down
** the tree or 2 to abort the tree walk.
................................................................................
  Parse *pParse;

  pNC = pWalker->u.pNC;
  assert( pNC!=0 );
  pParse = pNC->pParse;
  assert( pParse==pWalker->pParse );

  if( ExprHasProperty(pExpr, EP_Resolved) ) return WRC_Prune;
  ExprSetProperty(pExpr, EP_Resolved);
#ifndef NDEBUG
  if( pNC->pSrcList && pNC->pSrcList->nAlloc>0 ){
    SrcList *pSrcList = pNC->pSrcList;
    int i;
    for(i=0; i<pNC->pSrcList->nSrc; i++){
      assert( pSrcList->a[i].iCursor>=0 && pSrcList->a[i].iCursor<pParse->nTab);
................................................................................
        if( pDef==0 ){
          no_such_func = 1;
        }else{
          wrong_num_args = 1;
        }
      }else{
        is_agg = pDef->xFunc==0;
        if( pDef->funcFlags & SQLITE_FUNC_UNLIKELY ){
          ExprSetProperty(pExpr, EP_Unlikely|EP_Skip);
          if( n==2 ){
            pExpr->iTable = exprProbability(pList->a[1].pExpr);
            if( pExpr->iTable<0 ){
              sqlite3ErrorMsg(pParse, "second argument to likelihood() must be a "
                                      "constant between 0.0 and 1.0");
              pNC->nErr++;
            }
          }else{
            /* EVIDENCE-OF: R-61304-29449 The unlikely(X) function is equivalent to
            ** likelihood(X, 0.0625).
            ** EVIDENCE-OF: R-35738-39582 The unlikely(X) fucntion is short-hand for
            ** likelihood(X,0.0625). */
            pExpr->iTable = 62;  /* TUNING:  Default 2nd arg to unlikely() is 0.0625 */
          }             
        }
      }
#ifndef SQLITE_OMIT_AUTHORIZATION
      if( pDef ){
        auth = sqlite3AuthCheck(pParse, SQLITE_FUNCTION, 0, pDef->zName, 0);
        if( auth!=SQLITE_OK ){
          if( auth==SQLITE_DENY ){
            sqlite3ErrorMsg(pParse, "not authorized to use function: %s",
................................................................................
  if( op==TK_SELECT ){
    assert( pExpr->flags&EP_xIsSelect );
    return sqlite3ExprAffinity(pExpr->x.pSelect->pEList->a[0].pExpr);
  }
#ifndef SQLITE_OMIT_CAST
  if( op==TK_CAST ){
    assert( !ExprHasProperty(pExpr, EP_IntValue) );
    return sqlite3AffinityType(pExpr->u.zToken, 0);
  }
#endif
  if( (op==TK_AGG_COLUMN || op==TK_COLUMN || op==TK_REGISTER) 
   && pExpr->pTab!=0
  ){
    /* op==TK_REGISTER && pExpr->pTab!=0 happens when pExpr was originally
    ** a TK_COLUMN but was previously evaluated and cached in a register */
................................................................................
** and the pExpr parameter is returned unchanged.
*/
SQLITE_PRIVATE Expr *sqlite3ExprAddCollateToken(Parse *pParse, Expr *pExpr, Token *pCollName){
  if( pCollName->n>0 ){
    Expr *pNew = sqlite3ExprAlloc(pParse->db, TK_COLLATE, pCollName, 1);
    if( pNew ){
      pNew->pLeft = pExpr;
      pNew->flags |= EP_Collate|EP_Skip;
      pExpr = pNew;
    }
  }
  return pExpr;
}
SQLITE_PRIVATE Expr *sqlite3ExprAddCollateString(Parse *pParse, Expr *pExpr, const char *zC){
  Token s;
................................................................................
  assert( zC!=0 );
  s.z = zC;
  s.n = sqlite3Strlen30(s.z);
  return sqlite3ExprAddCollateToken(pParse, pExpr, &s);
}

/*
** Skip over any TK_COLLATE or TK_AS operators and any unlikely()
** or likelihood() function at the root of an expression.
*/
SQLITE_PRIVATE Expr *sqlite3ExprSkipCollate(Expr *pExpr){
  while( pExpr && ExprHasProperty(pExpr, EP_Skip) ){
    if( ExprHasProperty(pExpr, EP_Unlikely) ){
      assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
      assert( pExpr->x.pList->nExpr>0 );
      assert( pExpr->op==TK_FUNCTION );
      pExpr = pExpr->x.pList->a[0].pExpr;
    }else{
      assert( pExpr->op==TK_COLLATE || pExpr->op==TK_AS );
      pExpr = pExpr->pLeft;
    }
  }   
  return pExpr;
}

/*
** Return the collation sequence for the expression pExpr. If
** there is no defined collating sequence, return NULL.
**
................................................................................
** assigned.
*/
SQLITE_PRIVATE void sqlite3ExprAssignVarNumber(Parse *pParse, Expr *pExpr){
  sqlite3 *db = pParse->db;
  const char *z;

  if( pExpr==0 ) return;
  assert( !ExprHasProperty(pExpr, EP_IntValue|EP_Reduced|EP_TokenOnly) );
  z = pExpr->u.zToken;
  assert( z!=0 );
  assert( z[0]!=0 );
  if( z[1]==0 ){
    /* Wildcard of the form "?".  Assign the next variable number */
    assert( z[0]=='?' );
    pExpr->iColumn = (ynVar)(++pParse->nVar);
................................................................................
/*
** Recursively delete an expression tree.
*/
SQLITE_PRIVATE void sqlite3ExprDelete(sqlite3 *db, Expr *p){
  if( p==0 ) return;
  /* Sanity check: Assert that the IntValue is non-negative if it exists */
  assert( !ExprHasProperty(p, EP_IntValue) || p->u.iValue>=0 );
  if( !ExprHasProperty(p, EP_TokenOnly) ){
    /* The Expr.x union is never used at the same time as Expr.pRight */
    assert( p->x.pList==0 || p->pRight==0 );
    sqlite3ExprDelete(db, p->pLeft);
    sqlite3ExprDelete(db, p->pRight);
    if( ExprHasProperty(p, EP_MemToken) ) sqlite3DbFree(db, p->u.zToken);
    if( ExprHasProperty(p, EP_xIsSelect) ){
      sqlite3SelectDelete(db, p->x.pSelect);
    }else{
      sqlite3ExprListDelete(db, p->x.pList);
    }
  }
  if( !ExprHasProperty(p, EP_Static) ){
................................................................................
** to reduce a pristine expression tree from the parser.  The implementation
** of dupedExprStructSize() contain multiple assert() statements that attempt
** to enforce this constraint.
*/
static int dupedExprStructSize(Expr *p, int flags){
  int nSize;
  assert( flags==EXPRDUP_REDUCE || flags==0 ); /* Only one flag value allowed */
  assert( EXPR_FULLSIZE<=0xfff );
  assert( (0xfff & (EP_Reduced|EP_TokenOnly))==0 );
  if( 0==(flags&EXPRDUP_REDUCE) ){
    nSize = EXPR_FULLSIZE;
  }else{
    assert( !ExprHasProperty(p, EP_TokenOnly|EP_Reduced) );
    assert( !ExprHasProperty(p, EP_FromJoin) ); 
    assert( !ExprHasProperty(p, EP_MemToken) );
    assert( !ExprHasProperty(p, EP_NoReduce) );
    if( p->pLeft || p->x.pList ){
      nSize = EXPR_REDUCEDSIZE | EP_Reduced;
    }else{
      assert( p->pRight==0 );
      nSize = EXPR_TOKENONLYSIZE | EP_TokenOnly;
    }
  }
  return nSize;
}

/*
................................................................................
      }else{
        int nSize = exprStructSize(p);
        memcpy(zAlloc, p, nSize);
        memset(&zAlloc[nSize], 0, EXPR_FULLSIZE-nSize);
      }

      /* Set the EP_Reduced, EP_TokenOnly, and EP_Static flags appropriately. */
      pNew->flags &= ~(EP_Reduced|EP_TokenOnly|EP_Static|EP_MemToken);
      pNew->flags |= nStructSize & (EP_Reduced|EP_TokenOnly);
      pNew->flags |= staticFlag;

      /* Copy the p->u.zToken string, if any. */
      if( nToken ){
        char *zToken = pNew->u.zToken = (char*)&zAlloc[nNewSize];
        memcpy(zToken, p->u.zToken, nToken);
................................................................................
          pNew->x.pSelect = sqlite3SelectDup(db, p->x.pSelect, isReduced);
        }else{
          pNew->x.pList = sqlite3ExprListDup(db, p->x.pList, isReduced);
        }
      }

      /* Fill in pNew->pLeft and pNew->pRight. */
      if( ExprHasProperty(pNew, EP_Reduced|EP_TokenOnly) ){
        zAlloc += dupedExprNodeSize(p, flags);
        if( ExprHasProperty(pNew, EP_Reduced) ){
          pNew->pLeft = exprDup(db, p->pLeft, EXPRDUP_REDUCE, &zAlloc);
          pNew->pRight = exprDup(db, p->pRight, EXPRDUP_REDUCE, &zAlloc);
        }
        if( pzBuffer ){
          *pzBuffer = zAlloc;
        }
      }else{

        if( !ExprHasProperty(p, EP_TokenOnly) ){
          pNew->pLeft = sqlite3ExprDup(db, p->pLeft, 0);
          pNew->pRight = sqlite3ExprDup(db, p->pRight, 0);
        }
      }

    }
  }
................................................................................
**
*/
static int exprNodeIsConstant(Walker *pWalker, Expr *pExpr){

  /* If pWalker->u.i is 3 then any term of the expression that comes from
  ** the ON or USING clauses of a join disqualifies the expression
  ** from being considered constant. */
  if( pWalker->u.i==3 && ExprHasProperty(pExpr, EP_FromJoin) ){
    pWalker->u.i = 0;
    return WRC_Abort;
  }

  switch( pExpr->op ){
    /* Consider functions to be constant if all their arguments are constant
    ** and pWalker->u.i==2 */
................................................................................
    case TK_UPLUS: {
      rc = sqlite3ExprIsInteger(p->pLeft, pValue);
      break;
    }
    case TK_UMINUS: {
      int v;
      if( sqlite3ExprIsInteger(p->pLeft, &v) ){
        assert( v!=(-2147483647-1) );
        *pValue = -v;
        rc = 1;
      }
      break;
    }
    default: break;
  }
................................................................................
    eType = IN_INDEX_EPH;
    if( prNotFound ){
      *prNotFound = rMayHaveNull = ++pParse->nMem;
      sqlite3VdbeAddOp2(v, OP_Null, 0, *prNotFound);
    }else{
      testcase( pParse->nQueryLoop>0 );
      pParse->nQueryLoop = 0;
      if( pX->pLeft->iColumn<0 && !ExprHasProperty(pX, EP_xIsSelect) ){
        eType = IN_INDEX_ROWID;
      }
    }
    sqlite3CodeSubselect(pParse, pX, rMayHaveNull, eType==IN_INDEX_ROWID);
    pParse->nQueryLoop = savedNQueryLoop;
  }else{
    pX->iTable = iTab;
................................................................................
  **    *  The right-hand side is a correlated subquery
  **    *  The right-hand side is an expression list containing variables
  **    *  We are inside a trigger
  **
  ** If all of the above are false, then we can run this code just once
  ** save the results, and reuse the same result on subsequent invocations.
  */
  if( !ExprHasProperty(pExpr, EP_VarSelect) ){
    testAddr = sqlite3CodeOnce(pParse);
  }

#ifndef SQLITE_OMIT_EXPLAIN
  if( pParse->explain==2 ){
    char *zMsg = sqlite3MPrintf(
        pParse->db, "EXECUTE %s%s SUBQUERY %d", testAddr>=0?"":"CORRELATED ",
................................................................................
      pSel->pLimit = sqlite3PExpr(pParse, TK_INTEGER, 0, 0,
                                  &sqlite3IntTokens[1]);
      pSel->iLimit = 0;
      if( sqlite3Select(pParse, pSel, &dest) ){
        return 0;
      }
      rReg = dest.iSDParm;
      ExprSetVVAProperty(pExpr, EP_NoReduce);
      break;
    }
  }

  if( testAddr>=0 ){
    sqlite3VdbeJumpHere(v, testAddr);
  }
................................................................................
  for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
    int r = p->iReg;
    if( r>=iFrom && r<=iTo ) return 1;    /*NO_TEST*/
  }
  return 0;
}
#endif /* SQLITE_DEBUG || SQLITE_COVERAGE_TEST */

/*
** Convert an expression node to a TK_REGISTER
*/
static void exprToRegister(Expr *p, int iReg){
  p->op2 = p->op;
  p->op = TK_REGISTER;
  p->iTable = iReg;
  ExprClearProperty(p, EP_Skip);
}

/*
** Generate code into the current Vdbe to evaluate the given
** expression.  Attempt to store the results in register "target".
** Return the register where results are stored.
**
** With this routine, there is no guarantee that results will
................................................................................
    }
#ifndef SQLITE_OMIT_CAST
    case TK_CAST: {
      /* Expressions of the form:   CAST(pLeft AS token) */
      int aff, to_op;
      inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
      assert( !ExprHasProperty(pExpr, EP_IntValue) );
      aff = sqlite3AffinityType(pExpr->u.zToken, 0);
      to_op = aff - SQLITE_AFF_TEXT + OP_ToText;
      assert( to_op==OP_ToText    || aff!=SQLITE_AFF_TEXT    );
      assert( to_op==OP_ToBlob    || aff!=SQLITE_AFF_NONE    );
      assert( to_op==OP_ToNumeric || aff!=SQLITE_AFF_NUMERIC );
      assert( to_op==OP_ToInt     || aff!=SQLITE_AFF_INTEGER );
      assert( to_op==OP_ToReal    || aff!=SQLITE_AFF_REAL    );
      testcase( to_op==OP_ToText );
................................................................................
      int i;                 /* Loop counter */
      u8 enc = ENC(db);      /* The text encoding used by this database */
      CollSeq *pColl = 0;    /* A collating sequence */

      assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
      testcase( op==TK_CONST_FUNC );
      testcase( op==TK_FUNCTION );
      if( ExprHasProperty(pExpr, EP_TokenOnly) ){
        pFarg = 0;
      }else{
        pFarg = pExpr->x.pList;
      }
      nFarg = pFarg ? pFarg->nExpr : 0;
      assert( !ExprHasProperty(pExpr, EP_IntValue) );
      zId = pExpr->u.zToken;
................................................................................
        break;
      }

      /* Attempt a direct implementation of the built-in COALESCE() and
      ** IFNULL() functions.  This avoids unnecessary evalation of
      ** arguments past the first non-NULL argument.
      */
      if( pDef->funcFlags & SQLITE_FUNC_COALESCE ){
        int endCoalesce = sqlite3VdbeMakeLabel(v);
        assert( nFarg>=2 );
        sqlite3ExprCode(pParse, pFarg->a[0].pExpr, target);
        for(i=1; i<nFarg; i++){
          sqlite3VdbeAddOp2(v, OP_NotNull, target, endCoalesce);
          sqlite3ExprCacheRemove(pParse, target, 1);
          sqlite3ExprCachePush(pParse);
................................................................................
          sqlite3ExprCode(pParse, pFarg->a[i].pExpr, target);
          sqlite3ExprCachePop(pParse, 1);
        }
        sqlite3VdbeResolveLabel(v, endCoalesce);
        break;
      }

      /* The UNLIKELY() function is a no-op.  The result is the value
      ** of the first argument.
      */
      if( pDef->funcFlags & SQLITE_FUNC_UNLIKELY ){
        assert( nFarg>=1 );
        sqlite3ExprCode(pParse, pFarg->a[0].pExpr, target);
        break;
      }

      if( pFarg ){
        r1 = sqlite3GetTempRange(pParse, nFarg);

        /* For length() and typeof() functions with a column argument,
        ** set the P5 parameter to the OP_Column opcode to OPFLAG_LENGTHARG
        ** or OPFLAG_TYPEOFARG respectively, to avoid unnecessary data
        ** loading.
        */
        if( (pDef->funcFlags & (SQLITE_FUNC_LENGTH|SQLITE_FUNC_TYPEOF))!=0 ){
          u8 exprOp;
          assert( nFarg==1 );
          assert( pFarg->a[0].pExpr!=0 );
          exprOp = pFarg->a[0].pExpr->op;
          if( exprOp==TK_COLUMN || exprOp==TK_AGG_COLUMN ){
            assert( SQLITE_FUNC_LENGTH==OPFLAG_LENGTHARG );
            assert( SQLITE_FUNC_TYPEOF==OPFLAG_TYPEOFARG );
            testcase( (pDef->funcFlags&~SQLITE_FUNC_ENCMASK)
                       ==SQLITE_FUNC_LENGTH );
            pFarg->a[0].pExpr->op2 = pDef->funcFlags&~SQLITE_FUNC_ENCMASK;
          }
        }

        sqlite3ExprCachePush(pParse);     /* Ticket 2ea2425d34be */
        sqlite3ExprCodeExprList(pParse, pFarg, r1, 1);
        sqlite3ExprCachePop(pParse, 1);   /* Ticket 2ea2425d34be */
      }else{
................................................................................
        pDef = sqlite3VtabOverloadFunction(db, pDef, nFarg, pFarg->a[0].pExpr);
      }
#endif
      for(i=0; i<nFarg; i++){
        if( i<32 && sqlite3ExprIsConstant(pFarg->a[i].pExpr) ){
          constMask |= (1<<i);
        }
        if( (pDef->funcFlags & SQLITE_FUNC_NEEDCOLL)!=0 && !pColl ){
          pColl = sqlite3ExprCollSeq(pParse, pFarg->a[i].pExpr);
        }
      }
      if( pDef->funcFlags & SQLITE_FUNC_NEEDCOLL ){
        if( !pColl ) pColl = db->pDfltColl; 
        sqlite3VdbeAddOp4(v, OP_CollSeq, 0, 0, 0, (char *)pColl, P4_COLLSEQ);
      }
      sqlite3VdbeAddOp4(v, OP_Function, constMask, r1, target,
                        (char*)pDef, P4_FUNCDEF);
      sqlite3VdbeChangeP5(v, (u8)nFarg);
      if( nFarg ){
................................................................................
    **   CASE WHEN e1 THEN r1 WHEN e2 THEN r2 ... WHEN eN THEN rN ELSE y END
    **
    ** Form A is can be transformed into the equivalent form B as follows:
    **   CASE WHEN x=e1 THEN r1 WHEN x=e2 THEN r2 ...
    **        WHEN x=eN THEN rN ELSE y END
    **
    ** X (if it exists) is in pExpr->pLeft.
    ** Y is in the last element of pExpr->x.pList if pExpr->x.pList->nExpr is
    ** odd.  The Y is also optional.  If the number of elements in x.pList
    ** is even, then Y is omitted and the "otherwise" result is NULL.
    ** Ei is in pExpr->pList->a[i*2] and Ri is pExpr->pList->a[i*2+1].
    **
    ** The result of the expression is the Ri for the first matching Ei,
    ** or if there is no matching Ei, the ELSE term Y, or if there is
    ** no ELSE term, NULL.
    */
    default: assert( op==TK_CASE ); {
................................................................................
      Expr opCompare;                   /* The X==Ei expression */
      Expr cacheX;                      /* Cached expression X */
      Expr *pX;                         /* The X expression */
      Expr *pTest = 0;                  /* X==Ei (form A) or just Ei (form B) */
      VVA_ONLY( int iCacheLevel = pParse->iCacheLevel; )

      assert( !ExprHasProperty(pExpr, EP_xIsSelect) && pExpr->x.pList );

      assert(pExpr->x.pList->nExpr > 0);
      pEList = pExpr->x.pList;
      aListelem = pEList->a;
      nExpr = pEList->nExpr;
      endLabel = sqlite3VdbeMakeLabel(v);
      if( (pX = pExpr->pLeft)!=0 ){
        cacheX = *pX;
        testcase( pX->op==TK_COLUMN );
        testcase( pX->op==TK_REGISTER );
        exprToRegister(&cacheX, sqlite3ExprCodeTemp(pParse, pX, &regFree1));
        testcase( regFree1==0 );

        opCompare.op = TK_EQ;
        opCompare.pLeft = &cacheX;
        pTest = &opCompare;
        /* Ticket b351d95f9cd5ef17e9d9dbae18f5ca8611190001:
        ** The value in regFree1 might get SCopy-ed into the file result.
        ** So make sure that the regFree1 register is not reused for other
        ** purposes and possibly overwritten.  */
        regFree1 = 0;
      }
      for(i=0; i<nExpr-1; i=i+2){
        sqlite3ExprCachePush(pParse);
        if( pX ){
          assert( pTest!=0 );
          opCompare.pRight = aListelem[i].pExpr;
        }else{
          pTest = aListelem[i].pExpr;
        }
................................................................................
        testcase( aListelem[i+1].pExpr->op==TK_COLUMN );
        testcase( aListelem[i+1].pExpr->op==TK_REGISTER );
        sqlite3ExprCode(pParse, aListelem[i+1].pExpr, target);
        sqlite3VdbeAddOp2(v, OP_Goto, 0, endLabel);
        sqlite3ExprCachePop(pParse, 1);
        sqlite3VdbeResolveLabel(v, nextCase);
      }
      if( (nExpr&1)!=0 ){
        sqlite3ExprCachePush(pParse);
        sqlite3ExprCode(pParse, pEList->a[nExpr-1].pExpr, target);
        sqlite3ExprCachePop(pParse, 1);
      }else{
        sqlite3VdbeAddOp2(v, OP_Null, 0, target);
      }
      assert( db->mallocFailed || pParse->nErr>0 
           || pParse->iCacheLevel==iCacheLevel );
      sqlite3VdbeResolveLabel(v, endLabel);
................................................................................
  ** no way for a TK_REGISTER to exist here.  But it seems prudent to
  ** keep the ALWAYS() in case the conditions above change with future
  ** modifications or enhancements. */
  if( ALWAYS(pExpr->op!=TK_REGISTER) ){  
    int iMem;
    iMem = ++pParse->nMem;
    sqlite3VdbeAddOp2(v, OP_Copy, inReg, iMem);
    exprToRegister(pExpr, iMem);


  }
  return inReg;
}

#if defined(SQLITE_ENABLE_TREE_EXPLAIN)
/*
** Generate a human-readable explanation of an expression tree.
................................................................................
      sqlite3ExplainExpr(pOut, pExpr->pLeft);
      break;
    }
#ifndef SQLITE_OMIT_CAST
    case TK_CAST: {
      /* Expressions of the form:   CAST(pLeft AS token) */
      const char *zAff = "unk";
      switch( sqlite3AffinityType(pExpr->u.zToken, 0) ){
        case SQLITE_AFF_TEXT:    zAff = "TEXT";     break;
        case SQLITE_AFF_NONE:    zAff = "NONE";     break;
        case SQLITE_AFF_NUMERIC: zAff = "NUMERIC";  break;
        case SQLITE_AFF_INTEGER: zAff = "INTEGER";  break;
        case SQLITE_AFF_REAL:    zAff = "REAL";     break;
      }
      sqlite3ExplainPrintf(pOut, "CAST-%s(", zAff);
................................................................................
      break;
    }

    case TK_AGG_FUNCTION:
    case TK_CONST_FUNC:
    case TK_FUNCTION: {
      ExprList *pFarg;       /* List of function arguments */
      if( ExprHasProperty(pExpr, EP_TokenOnly) ){
        pFarg = 0;
      }else{
        pFarg = pExpr->x.pList;
      }
      if( op==TK_AGG_FUNCTION ){
        sqlite3ExplainPrintf(pOut, "AGG_FUNCTION%d:%s(",
                             pExpr->op2, pExpr->u.zToken);
................................................................................
  if( isAppropriateForFactoring(pExpr) ){
    int r1 = ++pParse->nMem;
    int r2 = sqlite3ExprCodeTarget(pParse, pExpr, r1);
    /* If r2!=r1, it means that register r1 is never used.  That is harmless
    ** but suboptimal, so we want to know about the situation to fix it.
    ** Hence the following assert: */
    assert( r2==r1 );
    exprToRegister(pExpr, r2);


    return WRC_Prune;
  }
  return WRC_Continue;
}

/*
** Preevaluate constant subexpressions within pExpr and store the
................................................................................
  exprAnd.pRight = &compRight;
  compLeft.op = TK_GE;
  compLeft.pLeft = &exprX;
  compLeft.pRight = pExpr->x.pList->a[0].pExpr;
  compRight.op = TK_LE;
  compRight.pLeft = &exprX;
  compRight.pRight = pExpr->x.pList->a[1].pExpr;
  exprToRegister(&exprX, sqlite3ExprCodeTemp(pParse, &exprX, &regFree1));


  if( jumpIfTrue ){
    sqlite3ExprIfTrue(pParse, &exprAnd, dest, jumpIfNull);
  }else{
    sqlite3ExprIfFalse(pParse, &exprAnd, dest, jumpIfNull);
  }
  sqlite3ReleaseTempReg(pParse, regFree1);

................................................................................
** just might result in some slightly slower code.  But returning
** an incorrect 0 or 1 could lead to a malfunction.
*/
SQLITE_PRIVATE int sqlite3ExprCompare(Expr *pA, Expr *pB, int iTab){
  if( pA==0||pB==0 ){
    return pB==pA ? 0 : 2;
  }
  assert( !ExprHasProperty(pA, EP_TokenOnly|EP_Reduced) );
  assert( !ExprHasProperty(pB, EP_TokenOnly|EP_Reduced) );
  if( ExprHasProperty(pA, EP_xIsSelect) || ExprHasProperty(pB, EP_xIsSelect) ){
    return 2;
  }
  if( (pA->flags & EP_Distinct)!=(pB->flags & EP_Distinct) ) return 2;
  if( pA->op!=pB->op && (pA->op!=TK_REGISTER || pA->op2!=pB->op) ){
    if( pA->op==TK_COLLATE && sqlite3ExprCompare(pA->pLeft, pB, iTab)<2 ){
      return 1;
................................................................................
      testcase( pExpr->op==TK_COLUMN );
      /* Check to see if the column is in one of the tables in the FROM
      ** clause of the aggregate query */
      if( ALWAYS(pSrcList!=0) ){
        struct SrcList_item *pItem = pSrcList->a;
        for(i=0; i<pSrcList->nSrc; i++, pItem++){
          struct AggInfo_col *pCol;
          assert( !ExprHasProperty(pExpr, EP_TokenOnly|EP_Reduced) );
          if( pExpr->iTable==pItem->iCursor ){
            /* If we reach this point, it means that pExpr refers to a table
            ** that is in the FROM clause of the aggregate query.  
            **
            ** Make an entry for the column in pAggInfo->aCol[] if there
            ** is not an entry there already.
            */
................................................................................
              }
            }
            /* There is now an entry for pExpr in pAggInfo->aCol[] (either
            ** because it was there before or because we just created it).
            ** Convert the pExpr to be a TK_AGG_COLUMN referring to that
            ** pAggInfo->aCol[] entry.
            */
            ExprSetVVAProperty(pExpr, EP_NoReduce);
            pExpr->pAggInfo = pAggInfo;
            pExpr->op = TK_AGG_COLUMN;
            pExpr->iAgg = (i16)k;
            break;
          } /* endif pExpr->iTable==pItem->iCursor */
        } /* end loop over pSrcList */
      }
................................................................................
            }else{
              pItem->iDistinct = -1;
            }
          }
        }
        /* Make pExpr point to the appropriate pAggInfo->aFunc[] entry
        */
        assert( !ExprHasProperty(pExpr, EP_TokenOnly|EP_Reduced) );
        ExprSetVVAProperty(pExpr, EP_NoReduce);
        pExpr->iAgg = (i16)i;
        pExpr->pAggInfo = pAggInfo;
        return WRC_Prune;
      }else{
        return WRC_Continue;
      }
    }
................................................................................
    return;
  }

  /* Ensure the default expression is something that sqlite3ValueFromExpr()
  ** can handle (i.e. not CURRENT_TIME etc.)
  */
  if( pDflt ){
    sqlite3_value *pVal = 0;
    if( sqlite3ValueFromExpr(db, pDflt, SQLITE_UTF8, SQLITE_AFF_NONE, &pVal) ){
      db->mallocFailed = 1;
      return;
    }
    if( !pVal ){
      sqlite3ErrorMsg(pParse, "Cannot add a column with non-constant default");
      return;
................................................................................
  return;
}
#endif  /* SQLITE_ALTER_TABLE */

/************** End of alter.c ***********************************************/
/************** Begin file analyze.c *****************************************/
/*
** 2005-07-08
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
................................................................................
** to help it make better decisions about how to perform queries.
**
** The following system tables are or have been supported:
**
**    CREATE TABLE sqlite_stat1(tbl, idx, stat);
**    CREATE TABLE sqlite_stat2(tbl, idx, sampleno, sample);
**    CREATE TABLE sqlite_stat3(tbl, idx, nEq, nLt, nDLt, sample);
**    CREATE TABLE sqlite_stat4(tbl, idx, nEq, nLt, nDLt, sample);
**
** Additional tables might be added in future releases of SQLite.
** The sqlite_stat2 table is not created or used unless the SQLite version
** is between 3.6.18 and 3.7.8, inclusive, and unless SQLite is compiled
** with SQLITE_ENABLE_STAT2.  The sqlite_stat2 table is deprecated.
** The sqlite_stat2 table is superseded by sqlite_stat3, which is only
** created and used by SQLite versions 3.7.9 and later and with
** SQLITE_ENABLE_STAT3 defined.  The functionality of sqlite_stat3
** is a superset of sqlite_stat2.  The sqlite_stat4 is an enhanced
** version of sqlite_stat3 and is only available when compiled with
** SQLITE_ENABLE_STAT4 and in SQLite versions 3.8.0 and later.  It is
** not possible to enable both STAT3 and STAT4 at the same time.  If they
** are both enabled, then STAT4 takes precedence.
**
** For most applications, sqlite_stat1 provides all the statisics required
** for the query planner to make good choices.
**
** Format of sqlite_stat1:
**
** There is normally one row per index, with the index identified by the
** name in the idx column.  The tbl column is the name of the table to
** which the index belongs.  In each such row, the stat column will be
** a string consisting of a list of integers.  The first integer in this
** list is the number of rows in the index.  (This is the same as the
** number of rows in the table, except for partial indices.)  The second
** integer is the average number of rows in the index that have the same
** value in the first column of the index.  The third integer is the average
** number of rows in the index that have the same value for the first two
** columns.  The N-th integer (for N>1) is the average number of rows in 
** the index which have the same value for the first N-1 columns.  For
** a K-column index, there will be K+1 integers in the stat column.  If
** the index is unique, then the last integer will be 1.
................................................................................
** The format for sqlite_stat2 is recorded here for legacy reference.  This
** version of SQLite does not support sqlite_stat2.  It neither reads nor
** writes the sqlite_stat2 table.  This version of SQLite only supports
** sqlite_stat3.
**
** Format for sqlite_stat3:
**
** The sqlite_stat3 format is a subset of sqlite_stat4.  Hence, the
** sqlite_stat4 format will be described first.  Further information
** about sqlite_stat3 follows the sqlite_stat4 description.
**

** Format for sqlite_stat4:
**
** As with sqlite_stat2, the sqlite_stat4 table contains histogram data
** to aid the query planner in choosing good indices based on the values
** that indexed columns are compared against in the WHERE clauses of
** queries.
**
** The sqlite_stat4 table contains multiple entries for each index.
** The idx column names the index and the tbl column is the table of the
** index.  If the idx and tbl columns are the same, then the sample is
** of the INTEGER PRIMARY KEY.  The sample column is a blob which is the


** binary encoding of a key from the index, with the trailing rowid
** omitted.  The nEq column is a list of integers.  The first integer
** is the approximate number of entries in the index whose left-most 
** column exactly matches the left-most column of the sample.  The second
** integer in nEq is the approximate number of entries in the index where
** the first two columns match the first two columns of the sample.
** And so forth.  nLt is another list of integers that show the approximate
** number of entries that are strictly less than the sample.  The first
** integer in nLt contains the number of entries in the index where the
** left-most column is less than the left-most column of the sample.
** The K-th integer in the nLt entry is the number of index entries 
** where the first K columns are less than the first K columns of the
** sample.  The nDLt column is like nLt except that it contains the 
** number of distinct entries in the index that are less than the
** sample.
**









** There can be an arbitrary number of sqlite_stat4 entries per index.
** The ANALYZE command will typically generate sqlite_stat4 tables
** that contain between 10 and 40 samples which are distributed across
** the key space, though not uniformly, and which include samples with
** large nEq values.
**
** Format for sqlite_stat3 redux:
**
** The sqlite_stat3 table is like sqlite_stat4 except that it only
** looks at the left-most column of the index.  The sqlite_stat3.sample
** column contains the actual value of the left-most column instead
** of a blob encoding of the complete index key as is found in
** sqlite_stat4.sample.  The nEq, nLt, and nDLt entries of sqlite_stat3
** all contain just a single integer which is the same as the first
** integer in the equivalent columns in sqlite_stat4.
*/
#ifndef SQLITE_OMIT_ANALYZE

#if defined(SQLITE_ENABLE_STAT4)
# define IsStat4     1
# define IsStat3     0
#elif defined(SQLITE_ENABLE_STAT3)
# define IsStat4     0
# define IsStat3     1
#else
# define IsStat4     0
# define IsStat3     0
# undef SQLITE_STAT4_SAMPLES
# define SQLITE_STAT4_SAMPLES 1
#endif
#define IsStat34    (IsStat3+IsStat4)  /* 1 for STAT3 or STAT4. 0 otherwise */

/*
** This routine generates code that opens the sqlite_statN tables.



** The sqlite_stat1 table is always relevant.  sqlite_stat2 is now
** obsolete.  sqlite_stat3 and sqlite_stat4 are only opened when
** appropriate compile-time options are provided.
**
** If the sqlite_statN tables do not previously exist, it is created.


**
** Argument zWhere may be a pointer to a buffer containing a table name,
** or it may be a NULL pointer. If it is not NULL, then all entries in

** the sqlite_statN tables associated with the named table are deleted.
** If zWhere==0, then code is generated to delete all stat table entries.
*/
static void openStatTable(
  Parse *pParse,          /* Parsing context */
  int iDb,                /* The database we are looking in */
  int iStatCur,           /* Open the sqlite_stat1 table on this cursor */
  const char *zWhere,     /* Delete entries for this table or index */
  const char *zWhereType  /* Either "tbl" or "idx" */
){
  static const struct {
    const char *zName;
    const char *zCols;
  } aTable[] = {
    { "sqlite_stat1", "tbl,idx,stat" },
#if defined(SQLITE_ENABLE_STAT4)
    { "sqlite_stat4", "tbl,idx,neq,nlt,ndlt,sample" },
    { "sqlite_stat3", 0 },
#elif defined(SQLITE_ENABLE_STAT3)
    { "sqlite_stat3", "tbl,idx,neq,nlt,ndlt,sample" },
    { "sqlite_stat4", 0 },
#else
    { "sqlite_stat3", 0 },
    { "sqlite_stat4", 0 },
#endif
  };




  int i;
  sqlite3 *db = pParse->db;
  Db *pDb;
  Vdbe *v = sqlite3GetVdbe(pParse);
  int aRoot[ArraySize(aTable)];
  u8 aCreateTbl[ArraySize(aTable)];

  if( v==0 ) return;
  assert( sqlite3BtreeHoldsAllMutexes(db) );
  assert( sqlite3VdbeDb(v)==db );
  pDb = &db->aDb[iDb];

  /* Create new statistic tables if they do not exist, or clear them
  ** if they do already exist.
  */
  for(i=0; i<ArraySize(aTable); i++){
    const char *zTab = aTable[i].zName;
    Table *pStat;
    if( (pStat = sqlite3FindTable(db, zTab, pDb->zName))==0 ){
      if( aTable[i].zCols ){
        /* The sqlite_statN table does not exist. Create it. Note that a 
        ** side-effect of the CREATE TABLE statement is to leave the rootpage 
        ** of the new table in register pParse->regRoot. This is important 
        ** because the OpenWrite opcode below will be needing it. */
        sqlite3NestedParse(pParse,
            "CREATE TABLE %Q.%s(%s)", pDb->zName, zTab, aTable[i].zCols
        );
        aRoot[i] = pParse->regRoot;
        aCreateTbl[i] = OPFLAG_P2ISREG;
      }
    }else{
      /* The table already exists. If zWhere is not NULL, delete all entries 
      ** associated with the table zWhere. If zWhere is NULL, delete the
      ** entire contents of the table. */
      aRoot[i] = pStat->tnum;
      aCreateTbl[i] = 0;
      sqlite3TableLock(pParse, iDb, aRoot[i], 1, zTab);
      if( zWhere ){
        sqlite3NestedParse(pParse,
           "DELETE FROM %Q.%s WHERE %s=%Q",
           pDb->zName, zTab, zWhereType, zWhere
        );
      }else{
        /* The sqlite_stat[134] table already exists.  Delete all rows. */
        sqlite3VdbeAddOp2(v, OP_Clear, aRoot[i], iDb);
      }
    }
  }

  /* Open the sqlite_stat[134] tables for writing. */
  for(i=0; aTable[i].zCols; i++){
    assert( i<ArraySize(aTable) );
    sqlite3VdbeAddOp3(v, OP_OpenWrite, iStatCur+i, aRoot[i], iDb);
    sqlite3VdbeChangeP4(v, -1, (char *)3, P4_INT32);
    sqlite3VdbeChangeP5(v, aCreateTbl[i]);
  }
}

/*
** Recommended number of samples for sqlite_stat4
*/
#ifndef SQLITE_STAT4_SAMPLES
# define SQLITE_STAT4_SAMPLES 24
#endif

/*
** Three SQL functions - stat_init(), stat_push(), and stat_get() -
** share an instance of the following structure to hold their state
** information.
*/
typedef struct Stat4Accum Stat4Accum;
typedef struct Stat4Sample Stat4Sample;
struct Stat4Sample {
  tRowcnt *anEq;                  /* sqlite_stat4.nEq */
  tRowcnt *anDLt;                 /* sqlite_stat4.nDLt */
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
  tRowcnt *anLt;                  /* sqlite_stat4.nLt */
  i64 iRowid;                     /* Rowid in main table of the key */
  u8 isPSample;                   /* True if a periodic sample */
  int iCol;                       /* If !isPSample, the reason for inclusion */
  u32 iHash;                      /* Tiebreaker hash */
#endif
};                                                    
struct Stat4Accum {
  tRowcnt nRow;             /* Number of rows in the entire table */
  tRowcnt nPSample;         /* How often to do a periodic sample */
  int nCol;                 /* Number of columns in index + rowid */
  int mxSample;             /* Maximum number of samples to accumulate */
  Stat4Sample current;      /* Current row as a Stat4Sample */
  u32 iPrn;                 /* Pseudo-random number used for sampling */
  Stat4Sample *aBest;       /* Array of (nCol-1) best samples */
  int iMin;                 /* Index in a[] of entry with minimum score */
  int nSample;              /* Current number of samples */
  int iGet;                 /* Index of current sample accessed by stat_get() */
  Stat4Sample *a;           /* Array of mxSample Stat4Sample objects */
};

/*
** Implementation of the stat_init(N,C) SQL function. The two parameters
** are the number of rows in the table or index (C) and the number of columns
** in the index (N).  The second argument (C) is only used for STAT3 and STAT4.
**
** This routine allocates the Stat4Accum object in heap memory. The return 
** value is a pointer to the the Stat4Accum object encoded as a blob (i.e. 
** the size of the blob is sizeof(void*) bytes). 
*/
static void statInit(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  Stat4Accum *p;
  int nCol;                       /* Number of columns in index being sampled */
  int nColUp;                     /* nCol rounded up for alignment */
  int n;                          /* Bytes of space to allocate */
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
  int mxSample = SQLITE_STAT4_SAMPLES;
#endif

  /* Decode the three function arguments */
  UNUSED_PARAMETER(argc);
  nCol = sqlite3_value_int(argv[0]);
  assert( nCol>1 );               /* >1 because it includes the rowid column */
  nColUp = sizeof(tRowcnt)<8 ? (nCol+1)&~1 : nCol;

  /* Allocate the space required for the Stat4Accum object */
  n = sizeof(*p) 
    + sizeof(tRowcnt)*nColUp                  /* Stat4Accum.anEq */
    + sizeof(tRowcnt)*nColUp                  /* Stat4Accum.anDLt */
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
    + sizeof(tRowcnt)*nColUp                  /* Stat4Accum.anLt */
    + sizeof(Stat4Sample)*(nCol+mxSample)   /* Stat4Accum.aBest[], a[] */
    + sizeof(tRowcnt)*3*nColUp*(nCol+mxSample)
#endif
  ;
  p = sqlite3MallocZero(n);
  if( p==0 ){
    sqlite3_result_error_nomem(context);
    return;
  }

  p->nRow = 0;
  p->nCol = nCol;
  p->current.anDLt = (tRowcnt*)&p[1];
  p->current.anEq = &p->current.anDLt[nColUp];

#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
  {
    u8 *pSpace;                     /* Allocated space not yet assigned */
    int i;                          /* Used to iterate through p->aSample[] */

    p->iGet = -1;
    p->mxSample = mxSample;
    p->nPSample = (tRowcnt)(sqlite3_value_int64(argv[1])/(mxSample/3+1) + 1);
    p->current.anLt = &p->current.anEq[nColUp];
    p->iPrn = nCol*0x689e962d ^ sqlite3_value_int(argv[1])*0xd0944565;
  
    /* Set up the Stat4Accum.a[] and aBest[] arrays */
    p->a = (struct Stat4Sample*)&p->current.anLt[nColUp];
    p->aBest = &p->a[mxSample];
    pSpace = (u8*)(&p->a[mxSample+nCol]);
    for(i=0; i<(mxSample+nCol); i++){
      p->a[i].anEq = (tRowcnt *)pSpace; pSpace += (sizeof(tRowcnt) * nColUp);
      p->a[i].anLt = (tRowcnt *)pSpace; pSpace += (sizeof(tRowcnt) * nColUp);
      p->a[i].anDLt = (tRowcnt *)pSpace; pSpace += (sizeof(tRowcnt) * nColUp);
    }
    assert( (pSpace - (u8*)p)==n );
  
    for(i=0; i<nCol; i++){
      p->aBest[i].iCol = i;
    }
  }
#endif

  /* Return a pointer to the allocated object to the caller */
  sqlite3_result_blob(context, p, sizeof(p), sqlite3_free);
}
static const FuncDef statInitFuncdef = {
  1+IsStat34,      /* nArg */
  SQLITE_UTF8,     /* funcFlags */
  0,               /* pUserData */
  0,               /* pNext */
  statInit,        /* xFunc */
  0,               /* xStep */
  0,               /* xFinalize */
  "stat_init",     /* zName */
  0,               /* pHash */
  0                /* pDestructor */
};

#ifdef SQLITE_ENABLE_STAT4
/*
** pNew and pOld are both candidate non-periodic samples selected for 
** the same column (pNew->iCol==pOld->iCol). Ignoring this column and 
** considering only any trailing columns and the sample hash value, this
** function returns true if sample pNew is to be preferred over pOld.
** In other words, if we assume that the cardinalities of the selected
** column for pNew and pOld are equal, is pNew to be preferred over pOld.
**
** This function assumes that for each argument sample, the contents of
** the anEq[] array from pSample->anEq[pSample->iCol+1] onwards are valid. 
*/
static int sampleIsBetterPost(
  Stat4Accum *pAccum, 
  Stat4Sample *pNew, 
  Stat4Sample *pOld
){
  int nCol = pAccum->nCol;
  int i;
  assert( pNew->iCol==pOld->iCol );
  for(i=pNew->iCol+1; i<nCol; i++){
    if( pNew->anEq[i]>pOld->anEq[i] ) return 1;
    if( pNew->anEq[i]<pOld->anEq[i] ) return 0;
  }
  if( pNew->iHash>pOld->iHash ) return 1;
  return 0;
}
#endif

#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
/*
** Return true if pNew is to be preferred over pOld.
**
** This function assumes that for each argument sample, the contents of
** the anEq[] array from pSample->anEq[pSample->iCol] onwards are valid. 
*/
static int sampleIsBetter(
  Stat4Accum *pAccum, 
  Stat4Sample *pNew, 
  Stat4Sample *pOld
){
  tRowcnt nEqNew = pNew->anEq[pNew->iCol];
  tRowcnt nEqOld = pOld->anEq[pOld->iCol];

  assert( pOld->isPSample==0 && pNew->isPSample==0 );
  assert( IsStat4 || (pNew->iCol==0 && pOld->iCol==0) );

  if( (nEqNew>nEqOld) ) return 1;
#ifdef SQLITE_ENABLE_STAT4
  if( nEqNew==nEqOld ){
    if( pNew->iCol<pOld->iCol ) return 1;
    return (pNew->iCol==pOld->iCol && sampleIsBetterPost(pAccum, pNew, pOld));
  }
  return 0;
#else
  return (nEqNew==nEqOld && pNew->iHash>pOld->iHash);
#endif
}

/*
** Copy the contents of object (*pFrom) into (*pTo).
*/
static void sampleCopy(Stat4Accum *p, Stat4Sample *pTo, Stat4Sample *pFrom){
  pTo->iRowid = pFrom->iRowid;
  pTo->isPSample = pFrom->isPSample;
  pTo->iCol = pFrom->iCol;
  pTo->iHash = pFrom->iHash;
  memcpy(pTo->anEq, pFrom->anEq, sizeof(tRowcnt)*p->nCol);
  memcpy(pTo->anLt, pFrom->