sqllogictest

#!/usr/bin/make
#
#### The suffix to add to executable files.  ".exe" for windows.
#    Nothing for unix.
#
E =

#### C Compile and options for use in building executables that 
#    will run on the target platform.
#
CC = gcc -g -Wall
#CC = gcc -g -Wall -DOMIT_ODBC=1 -fprofile-arcs -ftest-coverage
#CC += -DSQLITE_COVERAGE_TEST
CC += -DSQLITE_NO_SYNC=1

#### Extra arguments for linking the finished binary. 
#
LIB = $(LDFLAGS)

#
# nmake Makefile for sqllogictest
#
###############################################################################

# The toplevel directory of the source tree.  This is the directory that
# contains this "Makefile.msc".
#
TOP = .

# Check for the predefined command macro CC.  This should point to the compiler
# binary for the target platform.  If it is not defined, simply define it to
# the legacy default value 'cl.exe'.
#
!IFNDEF CC
CC = cl.exe
!ENDIF

# Check for the command macro LD.  This should point to the linker binary for
# the target platform.  If it is not defined, simply define it to the legacy
# default value 'link.exe'.
#
!IFNDEF LD
LD = link.exe
!ENDIF

# C compiler and options for use in building executables that
# will run on the target platform.  (BCC and TCC are usually the
# same unless your are cross-compiling.)
#
TCC = $(CC) -nologo -W3
TCC = $(TCC) -I$(TOP) -fp:precise

# Prevent warnings about "insecure" MSVC runtime library functions
# being used.
#
TCC = $(TCC) -D_CRT_SECURE_NO_DEPRECATE -D_CRT_SECURE_NO_WARNINGS
BCC = $(BCC) -D_CRT_SECURE_NO_DEPRECATE -D_CRT_SECURE_NO_WARNINGS
RCC = $(RCC) -D_CRT_SECURE_NO_DEPRECATE -D_CRT_SECURE_NO_WARNINGS

# Prevent warnings about "deprecated" POSIX functions being used.
#
TCC = $(TCC) -D_CRT_NONSTDC_NO_DEPRECATE -D_CRT_NONSTDC_NO_WARNINGS
BCC = $(BCC) -D_CRT_NONSTDC_NO_DEPRECATE -D_CRT_NONSTDC_NO_WARNINGS
RCC = $(RCC) -D_CRT_NONSTDC_NO_DEPRECATE -D_CRT_NONSTDC_NO_WARNINGS

# Add in any optional parameters specified on the commane line, e.g.
# nmake /f Makefile.msc all "OPTS=-DSQLITE_ENABLE_FOO=1 -DSQLITE_OMIT_FOO=1"
#
TCC = $(TCC) $(OPTS)
RCC = $(RCC) $(OPTS)

# This is the default Makefile target.  The objects listed here
# are what get build when you type just "make" with no arguments.
#
all:	sqllogictest.exe

# Rules to build individual *.lo files from files in the src directory.
#
md5.lo:	$(TOP)\md5.c
	$(TCC) -Fo$@ -c $(TOP)\md5.c

sqlite3.lo:	$(TOP)\sqlite3.c
	$(TCC) -Fo$@ -c $(TOP)\sqlite3.c

sqllogictest.exe:	md5.lo sqlite3.lo
	$(TCC) -Fe$@ $(TOP)\sqllogictest.c /link odbc32.lib md5.lo sqlite3.lo

clean:
	del /Q *.exp *.lo *.ilk *.lib *.obj *.ncb *.pdb *.sdf *.suo 2>NUL
	del /Q *.bsc *.cod *.da *.bb *.bbg gmon.out 2>NUL
	del /Q sqllogictest.exe 2>NUL

        /* Append length in bits and transform */
        ((uint32 *)ctx->in)[ 14 ] = ctx->bits[0];
        ((uint32 *)ctx->in)[ 15 ] = ctx->bits[1];

        MD5Transform(ctx->buf, (uint32 *)ctx->in);
        byteReverse((unsigned char *)ctx->buf, 4);
        memcpy(digest, ctx->buf, 16);
        memset(&ctx, 0, sizeof(ctx));    /* In case it is sensitive */
}

/*
** Convert a digest into base-16.  digest should be declared as
** "unsigned char digest[16]" in the calling function.  The MD5
** digest is stored in the first 16 bytes.  zBuf should
** be "char zBuf[33]".

for /R ..\test %%i in (*.test) do sqllogictest -odbc "DSN=slt.mssql;UID=slt;PWD=slt;" -verify %%i

for /R ..\test %%i in (*.test) do sqllogictest -odbc "DSN=slt.pgsql;UID=slt;PWD=slt;" -verify %%i

#!/usr/bin/tclsh
#
# Run this script in the "src" subdirectory of sqllogictest, after first
# compiling the ./sqllogictest binary, in order to verify correct output
# of all historical test cases.
#

set starttime [clock seconds]

if {$tcl_platform(platform)=="unix"} {
  set BIN ./sqllogictest
} else {
  set BIN ./sqllogictest.exe
}
if {![file exec $BIN]} {
  error "$BIN does not exist or is not executable.  Run make."
}

# add all test case file in the $subdir subdirectory to the
# set of all test case files in the global tcase() array.
#
proc search_for_test_cases {subdir} {
  foreach nx [glob -nocomplain $subdir/*] {
    if {[file isdir $nx]} {
      search_for_test_cases $nx
    } elseif {[string match *.test $nx]} {
      set ::tcase($nx) 1
    }
  }
}
search_for_test_cases ../test

# Run the tests
#
set totalerr 0
set totaltest 0
set totalrun 0
foreach tx [lsort [array names tcase]] {
  foreach opt {0 0xfff} {
    set opt "integrity_check;optimizer=[expr {$opt+0}]"
    catch {
      exec $BIN -verify -parameter $opt $tx
    } res
    puts $res
    if {[regexp {(\d+) errors out of (\d+) tests} $res all nerr ntst]} {
      incr totalerr $nerr
      incr totaltest $ntst
    } else {
      error "test did not complete: $BIN -verify -parameter optimizer=$opt $tx"
    }
    incr totalrun
  }
}

set endtime [clock seconds]
set totaltime [expr {$endtime - $starttime}]
puts "$totalerr errors out of $totaltest tests and $totalrun invocations\
      in $totaltime seconds"

**
** The DSN name and DB name are controlled by the defines
** SLT_DSN and SLT_DB.
**
*/
#ifndef OMIT_ODBC  /* Omit this module if OMIT_ODBC is defined */

#ifdef _WIN32
#include <windows.h>
#endif
#define SQL_NOUNICODEMAP
#include <sql.h>
#include <sqlext.h>

/*
** Append a value to a result set.  zValue is copied into memory obtained
** from malloc.  Or if zValue is NULL, then a NULL pointer is appended.
*/
static void ODBC3_appendValue(ODBC3_resAccum *p, const char *zValue){
  char *z;
  if( zValue ){
#ifdef _WIN32
    z = _strdup(zValue);
#else
    z = strdup(zValue);
#endif
    if( z==0 ){
      fprintf(stderr, "out of memory at %s:%d\n", __FILE__,__LINE__);
      exit(1);

    }else if( 0 == stricmp(zDmbsName, "mssql") ){
      for( i=0; !rc && (i+4<res.nUsed); i+=5 ){
        if(    (0 == stricmp(res.azValue[i], zDbName))
            && (0 == strcmp(res.azValue[i+1], "dbo"))
            && (strlen(res.azValue[i+2])>0)
            && (0 == strcmp(res.azValue[i+3], "TABLE"))
            && (0 == strcmp(res.azValue[i+4], "NULL"))
        ){
          sprintf(zSql, "DROP TABLE %s", res.azValue[i+2]);
          rc = ODBC3Statement(pODBC3conn, zSql, 0);
        }
      }
    }else if( 0 == stricmp(zDmbsName, "postgresql") ){
      for( i=0; !rc && (i+4<res.nUsed); i+=5 ){
        if(    (0 == stricmp(res.azValue[i], zDbName))
            && (0 == strcmp(res.azValue[i+1], "(empty)")
                 || 0 == strcmp(res.azValue[i+1], "NULL")
                 || 0 == stricmp(res.azValue[i+1], "public"))
            && (strlen(res.azValue[i+2])>0)
            && (0 == strcmp(res.azValue[i+3], "TABLE"))
            && (0 == strcmp(res.azValue[i+4], "(empty)")
                 || 0 == strcmp(res.azValue[i+4], "NULL"))
        ){
          sprintf(zSql, "DROP TABLE %s", res.azValue[i+2]);
          rc = ODBC3Statement(pODBC3conn, zSql, 0);
        }
      }
    }else{
      for( i=0; !rc && (i+4<res.nUsed); i+=5 ){

  ret = SQLGetInfo(pODBC3conn->dbc,
                   SQL_DBMS_NAME,
                   zDmbsName,
                   sizeof(zDmbsName),
                   &outLen);
  if( SQL_SUCCEEDED(ret) || (ret == SQL_SUCCESS_WITH_INFO) ){
    /* map Microsoft SQL Server -> mssql */
    if( stricmp("Microsoft SQL Server", zDmbsName)==0 ){
      *zName = "mssql";
    }else{
      *zName = zDmbsName;
    }
    return 0;
  }
  return 1;
}

**
** Use this interface as a model for other database engine interfaces.
*/
#include "sqlite3.h"
#include <ctype.h>
#include <stdio.h>

/*
** The SQLite database connection object
*/
typedef struct SQLiteConn SQLiteConn;
struct SQLiteConn {
  sqlite3 *db;            /* The database connection */
  unsigned flags;         /* Various flags */
};

/*
** Allowed values for SQLiteConn.flags
*/
#define FG_INTEGRITY_CHECK  0x0001    /* Run PRAGMA integrity_check */


/*
** Skip forward over whitespace in a string.
*/
static const char *skipWhitespace(const char *z){
  while( isspace(*z) ){ z++; }
  return z;

*/
static int sqliteConnect(
  void *NotUsed,              /* Argument from DbEngine object.  Not used */
  const char *zConnectStr,    /* Connection string */
  void **ppConn,              /* Write completed connection here */
  const char *zParam          /* Value of the -parameters command-line option */
){

  int rc;
  SQLiteConn *p;

  /* If the database filename is defined and the database already exists,
  ** then delete the database before we start, thus resetting it to an
  ** empty database.
  */
  if( zConnectStr==0 ) zConnectStr = "test.db";
  if( zConnectStr && zConnectStr[0] ){
#ifndef _WIN32
    unlink(zConnectStr);
#else
    _unlink(zConnectStr);
#endif
  }

  p = sqlite3_malloc( sizeof(*p) );
  if( p==0 ){
    return 1;
  }
  memset(p, 0, sizeof(*p));

  /* Open a connection to the new database.
  */
  rc = sqlite3_open(zConnectStr, &p->db);
  if( rc!=SQLITE_OK ){
    sqlite3_free(p);
    return 1;
  }
  if( zParam ){
    zParam = skipWhitespace(zParam);
    while( zParam[0] ){
      if( strncmp(zParam, "optimizer=", 10)==0 ){
        int x = atoi(&zParam[10]);
        sqlite3_test_control(SQLITE_TESTCTRL_OPTIMIZATIONS, p->db, x);
      }else if( strncmp(zParam, "integrity_check", 15)==0 ){
        p->flags |= FG_INTEGRITY_CHECK;
      }else{
        fprintf(stderr, "unknown parameter: [%s]\n", zParam);
        exit(1);
      }
      zParam = skipToNextParameter(zParam);
    }
  }
  sqlite3_exec(p->db, "PRAGMA synchronous=OFF", 0, 0, 0);
  *ppConn = (void*)p;
  return 0;  
}

/*
** Evaluate the single SQL statement given in zSql.  Return 0 on success.
** return non-zero if any error occurs.
*/
static int sqliteStatement(
  void *pConn,                /* Connection created by xConnect */
  const char *zSql,           /* SQL statement to evaluate */
  int bQuiet                  /* True to suppress printing errors. */
){
  int rc;
  SQLiteConn *p;
  

  p = (SQLiteConn*)pConn;
  rc = sqlite3_exec(p->db, zSql, 0, 0, 0);
  if( rc==SQLITE_OK && (p->flags & FG_INTEGRITY_CHECK)!=0 ){
    sqlite3_stmt *pStmt;
    rc = sqlite3_prepare_v2(p->db, "PRAGMA integrity_check;", -1, &pStmt, 0);
    if( rc!=SQLITE_OK ){
      fprintf(stderr, "cannot prepare integrity_check\n");
      rc = 1;
    }else{
      char *z;
      if( sqlite3_step(pStmt)!=SQLITE_ROW ){
        fprintf(stderr, "cannot run integrity_check\n");
        rc = 1;
      }else if( (z = (char*)sqlite3_column_text(pStmt,0))==0
            || strcmp(z,"ok")!=0
      ){
        fprintf(stderr, "integrity_check returns: %s\n", z);
        rc = 1;
      }else{
        rc = 0;
      }
      sqlite3_finalize(pStmt);
    }
  }
  return rc!=SQLITE_OK;
}

/*
** Structure used to accumulate a result set.
*/
typedef struct ResAccum ResAccum;

  char ***pazResult,          /* RETURN:  Array of result values */
  int *pnResult               /* RETURN:  Number of result values */
){
  sqlite3 *db;                /* The database connection */
  sqlite3_stmt *pStmt;        /* Prepared statement */
  int rc;                     /* Result code from subroutine calls */
  ResAccum res;               /* query result accumulator */
  SQLiteConn *p;              /* The database connection */
  char zBuffer[200];          /* Buffer to render numbers */

  memset(&res, 0, sizeof(res));
  p = (SQLiteConn*)pConn;
  db = p->db;
  rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0);
  if( rc!=SQLITE_OK ){
    sqlite3_finalize(pStmt);
    return 1;
  }
  if( strlen(zType)!=sqlite3_column_count(pStmt) ){
    fprintf(stderr, "wrong number of result columns: expected %d but got %d\n",

** database files.  If the database is deleted here, that is one approach.
** The other approach is to delete left-over databases in the xConnect
** method.  The SQLite interface takes the latter approach.
*/
static int sqliteDisconnect(
  void *pConn                 /* Connection created by xConnect */
){
  SQLiteConn *p = (SQLiteConn*)pConn;
  int rc;
  rc = sqlite3_close(p->db);
  sqlite3_free(p);
  if( sqlite3_memory_used()>0 ){
    fprintf(stderr, "memory leak after connection close\n");
    rc = 1;
  }
  return rc;
}

/*
** This routine is called to return the name of the DB engine
** used by the connection pConn.  This name may or may not
** be the same as specified in the DbEngine structure.
**

** "experimental".  Experimental interfaces are normally new
** features recently added to SQLite.  We do not anticipate changes
** to experimental interfaces but reserve the right to make minor changes
** if experience from use "in the wild" suggest such changes are prudent.
**
** The official C-language API documentation for SQLite is derived
** from comments in this file.  This file is the authoritative source
** on how SQLite interfaces are supposed to operate.
**
** The name of this file under configuration management is "sqlite.h.in".
** The makefile makes some minor changes to this file (such as inserting
** the version number) and changes its name to "sqlite3.h" as
** part of the build process.
*/
#ifndef SQLITE3_H
#define SQLITE3_H
#include <stdarg.h>     /* Needed for the definition of va_list */

/*
** Make sure we can call this stuff from C++.
*/
#ifdef __cplusplus
extern "C" {
#endif


/*
** Provide the ability to override linkage features of the interface.
*/
#ifndef SQLITE_EXTERN
# define SQLITE_EXTERN extern
#endif

#ifndef SQLITE_API
# define SQLITE_API
#endif
#ifndef SQLITE_CDECL
# define SQLITE_CDECL
#endif
#ifndef SQLITE_APICALL
# define SQLITE_APICALL
#endif
#ifndef SQLITE_STDCALL
# define SQLITE_STDCALL SQLITE_APICALL
#endif
#ifndef SQLITE_CALLBACK
# define SQLITE_CALLBACK
#endif
#ifndef SQLITE_SYSAPI
# define SQLITE_SYSAPI
#endif

/*
** These no-op macros are used in front of interfaces to mark those
** interfaces as either deprecated or experimental.  New applications
** should not use deprecated interfaces - they are supported for backwards
** compatibility only.  Application writers should be aware that
** experimental interfaces are subject to change in point releases.
**
** These macros used to resolve to various kinds of compiler magic that
** would generate warning messages when they were used.  But that
** compiler magic ended up generating such a flurry of bug reports
** that we have taken it all out and gone back to using simple

** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same
** numbers used in [SQLITE_VERSION].)^
** The SQLITE_VERSION_NUMBER for any given release of SQLite will also
** be larger than the release from which it is derived.  Either Y will
** be held constant and Z will be incremented or else Y will be incremented
** and Z will be reset to zero.
**
** Since [version 3.6.18] ([dateof:3.6.18]), 
** SQLite source code has been stored in the
** <a href="http://www.fossil-scm.org/">Fossil configuration management
** system</a>.  ^The SQLITE_SOURCE_ID macro evaluates to
** a string which identifies a particular check-in of SQLite
** within its configuration management system.  ^The SQLITE_SOURCE_ID
** 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        "3.15.0"
#define SQLITE_VERSION_NUMBER 3015000
#define SQLITE_SOURCE_ID      "2016-10-05 15:04:35 b2ef39b11f7c46e69e53439680c32adbb18903bd"

/*
** 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
** but are associated with the library instead of the header file.  ^(Cautious
** programmers might include assert() statements in their application to
** verify that values returned by these interfaces match the macros in
** the header, and thus ensure that the application is
** compiled with matching library and header files.
**
** <blockquote><pre>
** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
** assert( strcmp(sqlite3_sourceid(),SQLITE_SOURCE_ID)==0 );
** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
** </pre></blockquote>)^

** the desired setting of the [SQLITE_THREADSAFE] macro.
**
** This interface only reports on the compile-time mutex setting
** of the [SQLITE_THREADSAFE] flag.  If SQLite is compiled with
** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
** can be fully or partially disabled using a call to [sqlite3_config()]
** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
** or [SQLITE_CONFIG_SERIALIZED].  ^(The return value of the
** sqlite3_threadsafe() function shows only the compile-time setting of
** thread safety, not any run-time changes to that setting made by
** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
** is unchanged by calls to sqlite3_config().)^
**
** See the [threading mode] documentation for additional information.
*/

*/
#ifdef SQLITE_OMIT_FLOATING_POINT
# define double sqlite3_int64
#endif

/*
** CAPI3REF: Closing A Database Connection
** DESTRUCTOR: sqlite3
**
** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors
** for the [sqlite3] object.
** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if
** the [sqlite3] object is successfully destroyed and all associated
** resources are deallocated.
**
** ^If the database connection is associated with unfinalized prepared
** statements or unfinished sqlite3_backup objects then sqlite3_close()
** will leave the database connection open and return [SQLITE_BUSY].
** ^If sqlite3_close_v2() is called with unfinalized prepared statements
** and/or unfinished sqlite3_backups, then the database connection becomes
** an unusable "zombie" which will automatically be deallocated when the
** last prepared statement is finalized or the last sqlite3_backup is
** finished.  The sqlite3_close_v2() interface is intended for use with
** host languages that are garbage collected, and where the order in which
** destructors are called is arbitrary.
**
** Applications should [sqlite3_finalize | finalize] all [prepared statements],
** [sqlite3_blob_close | close] all [BLOB handles], and 
** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated
** with the [sqlite3] object prior to attempting to close the object.  ^If
** sqlite3_close_v2() is called on a [database connection] that still has
** outstanding [prepared statements], [BLOB handles], and/or
** [sqlite3_backup] objects then it returns [SQLITE_OK] and the deallocation
** of resources is deferred until all [prepared statements], [BLOB handles],
** and [sqlite3_backup] objects are also destroyed.
**
** ^If an [sqlite3] object is destroyed while a transaction is open,
** the transaction is automatically rolled back.
**
** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)]

** This is legacy and deprecated.  It is included for historical
** compatibility and is not documented.
*/
typedef int (*sqlite3_callback)(void*,int,char**, char**);

/*
** CAPI3REF: One-Step Query Execution Interface
** METHOD: sqlite3
**
** The sqlite3_exec() interface is a convenience wrapper around
** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
** that allows an application to run multiple statements of SQL
** without having to use a lot of C code. 
**
** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,

** ^If an error occurs while evaluating the SQL statements passed into
** sqlite3_exec(), then execution of the current statement stops and
** subsequent statements are skipped.  ^If the 5th parameter to sqlite3_exec()
** is not NULL then any error message is written into memory obtained
** from [sqlite3_malloc()] and passed back through the 5th parameter.
** To avoid memory leaks, the application should invoke [sqlite3_free()]
** on error message strings returned through the 5th parameter of
** sqlite3_exec() after the error message string is no longer needed.
** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
** NULL before returning.
**
** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
** routine returns SQLITE_ABORT without invoking the callback again and
** without running any subsequent SQL statements.

** to an empty string, or a pointer that contains only whitespace and/or 
** SQL comments, then no SQL statements are evaluated and the database
** is not changed.
**
** Restrictions:
**
** <ul>
** <li> The application must ensure that the 1st parameter to sqlite3_exec()
**      is a valid and open [database connection].
** <li> The application must not close the [database connection] specified by
**      the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
** <li> The application must not modify the SQL statement text passed into
**      the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
** </ul>
*/
SQLITE_API int sqlite3_exec(
  sqlite3*,                                  /* An open database */
  const char *sql,                           /* SQL to be evaluated */
  int (*callback)(void*,int,char**,char**),  /* Callback function */
  void *,                                    /* 1st argument to callback */
  char **errmsg                              /* Error msg written here */
);

/*
** CAPI3REF: Result Codes

** KEYWORDS: {result code definitions}
**
** Many SQLite functions return an integer result code from the set shown
** here in order to indicate success or failure.
**
** New error codes may be added in future versions of SQLite.
**
** See also: [extended result code definitions]

*/
#define SQLITE_OK           0   /* Successful result */
/* beginning-of-error-codes */
#define SQLITE_ERROR        1   /* SQL error or missing database */
#define SQLITE_INTERNAL     2   /* Internal logic error in SQLite */
#define SQLITE_PERM         3   /* Access permission denied */
#define SQLITE_ABORT        4   /* Callback routine requested an abort */

#define SQLITE_MISMATCH    20   /* Data type mismatch */
#define SQLITE_MISUSE      21   /* Library used incorrectly */
#define SQLITE_NOLFS       22   /* Uses OS features not supported on host */
#define SQLITE_AUTH        23   /* Authorization denied */
#define SQLITE_FORMAT      24   /* Auxiliary database format error */
#define SQLITE_RANGE       25   /* 2nd parameter to sqlite3_bind out of range */
#define SQLITE_NOTADB      26   /* File opened that is not a database file */
#define SQLITE_NOTICE      27   /* Notifications from sqlite3_log() */
#define SQLITE_WARNING     28   /* Warnings from sqlite3_log() */
#define SQLITE_ROW         100  /* sqlite3_step() has another row ready */
#define SQLITE_DONE        101  /* sqlite3_step() has finished executing */
/* end-of-error-codes */

/*
** CAPI3REF: Extended Result Codes

** KEYWORDS: {extended result code definitions}
**
** In its default configuration, SQLite API routines return one of 30 integer
** [result codes].  However, experience has shown that many of
** these result codes are too coarse-grained.  They do not provide as
** much information about problems as programmers might like.  In an effort to
** address this, newer versions of SQLite (version 3.3.8 [dateof:3.3.8]
** and later) include
** support for additional result codes that provide more detailed information
** about errors. These [extended result codes] are enabled or disabled
** on a per database connection basis using the
** [sqlite3_extended_result_codes()] API.  Or, the extended code for
** the most recent error can be obtained using
** [sqlite3_extended_errcode()].






*/
#define SQLITE_IOERR_READ              (SQLITE_IOERR | (1<<8))
#define SQLITE_IOERR_SHORT_READ        (SQLITE_IOERR | (2<<8))
#define SQLITE_IOERR_WRITE             (SQLITE_IOERR | (3<<8))
#define SQLITE_IOERR_FSYNC             (SQLITE_IOERR | (4<<8))
#define SQLITE_IOERR_DIR_FSYNC         (SQLITE_IOERR | (5<<8))
#define SQLITE_IOERR_TRUNCATE          (SQLITE_IOERR | (6<<8))

#define SQLITE_IOERR_DIR_CLOSE         (SQLITE_IOERR | (17<<8))
#define SQLITE_IOERR_SHMOPEN           (SQLITE_IOERR | (18<<8))
#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_IOERR_VNODE             (SQLITE_IOERR | (27<<8))
#define SQLITE_IOERR_AUTH              (SQLITE_IOERR | (28<<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_READONLY_DBMOVED        (SQLITE_READONLY | (4<<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))
#define SQLITE_CONSTRAINT_FOREIGNKEY   (SQLITE_CONSTRAINT | (3<<8))
#define SQLITE_CONSTRAINT_FUNCTION     (SQLITE_CONSTRAINT | (4<<8))
#define SQLITE_CONSTRAINT_NOTNULL      (SQLITE_CONSTRAINT | (5<<8))
#define SQLITE_CONSTRAINT_PRIMARYKEY   (SQLITE_CONSTRAINT | (6<<8))
#define SQLITE_CONSTRAINT_TRIGGER      (SQLITE_CONSTRAINT | (7<<8))
#define SQLITE_CONSTRAINT_UNIQUE       (SQLITE_CONSTRAINT | (8<<8))
#define SQLITE_CONSTRAINT_VTAB         (SQLITE_CONSTRAINT | (9<<8))
#define SQLITE_CONSTRAINT_ROWID        (SQLITE_CONSTRAINT |(10<<8))
#define SQLITE_NOTICE_RECOVER_WAL      (SQLITE_NOTICE | (1<<8))
#define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8))
#define SQLITE_WARNING_AUTOINDEX       (SQLITE_WARNING | (1<<8))
#define SQLITE_AUTH_USER               (SQLITE_AUTH | (1<<8))
#define SQLITE_OK_LOAD_PERMANENTLY     (SQLITE_OK | (1<<8))

/*
** CAPI3REF: Flags For File Open Operations
**
** These bit values are intended for use in the
** 3rd parameter to the [sqlite3_open_v2()] interface and
** in the 4th parameter to the [sqlite3_vfs.xOpen] method.

** first then the size of the file is extended, never the other
** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
** information is written to disk in the same order as calls
** to xWrite().  The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that
** after reboot following a crash or power loss, the only bytes in a
** file that were written at the application level might have changed
** and that adjacent bytes, even bytes within the same sector are
** guaranteed to be unchanged.  The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN
** flag indicate that a file cannot be deleted when open.  The
** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on
** read-only media and cannot be changed even by processes with
** elevated privileges.
*/
#define SQLITE_IOCAP_ATOMIC                 0x00000001
#define SQLITE_IOCAP_ATOMIC512              0x00000002
#define SQLITE_IOCAP_ATOMIC1K               0x00000004
#define SQLITE_IOCAP_ATOMIC2K               0x00000008
#define SQLITE_IOCAP_ATOMIC4K               0x00000010
#define SQLITE_IOCAP_ATOMIC8K               0x00000020
#define SQLITE_IOCAP_ATOMIC16K              0x00000040
#define SQLITE_IOCAP_ATOMIC32K              0x00000080
#define SQLITE_IOCAP_ATOMIC64K              0x00000100
#define SQLITE_IOCAP_SAFE_APPEND            0x00000200
#define SQLITE_IOCAP_SEQUENTIAL             0x00000400
#define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN  0x00000800
#define SQLITE_IOCAP_POWERSAFE_OVERWRITE    0x00001000
#define SQLITE_IOCAP_IMMUTABLE              0x00002000

/*
** CAPI3REF: File Locking Levels
**
** SQLite uses one of these integer values as the second
** argument to calls it makes to the xLock() and xUnlock() methods
** of an [sqlite3_io_methods] object.

** integer opcode.  The third argument is a generic pointer intended to
** point to a structure that may contain arguments or space in which to
** write return values.  Potential uses for xFileControl() might be
** functions to enable blocking locks with timeouts, to change the
** locking strategy (for example to use dot-file locks), to inquire
** about the status of a lock, or to break stale locks.  The SQLite
** core reserves all opcodes less than 100 for its own use.
** A [file control opcodes | list of opcodes] less than 100 is available.
** Applications that define a custom xFileControl method should use opcodes
** greater than 100 to avoid conflicts.  VFS implementations should
** return [SQLITE_NOTFOUND] for file control opcodes that they do not
** recognize.
**
** The xSectorSize() method returns the sector size of the
** device that underlies the file.  The sector size is the

  int (*xDeviceCharacteristics)(sqlite3_file*);
  /* Methods above are valid for version 1 */
  int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
  int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
  void (*xShmBarrier)(sqlite3_file*);
  int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
  /* Methods above are valid for version 2 */
  int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp);
  int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p);
  /* Methods above are valid for version 3 */
  /* Additional methods may be added in future releases */
};

/*
** CAPI3REF: Standard File Control Opcodes
** KEYWORDS: {file control opcodes} {file control opcode}
**
** These integer constants are opcodes for the xFileControl method
** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
** interface.
**
** <ul>
** <li>[[SQLITE_FCNTL_LOCKSTATE]]
** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging.  This
** opcode causes the xFileControl method to write the current state of
** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
** into an integer that the pArg argument points to. This capability
** is used during testing and is only available when the SQLITE_TEST
** compile-time option is used.
**
** <li>[[SQLITE_FCNTL_SIZE_HINT]]
** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
** layer a hint of how large the database file will grow to be during the
** current transaction.  This hint is not guaranteed to be accurate but it
** is often close.  The underlying VFS might choose to preallocate database
** file space based on this hint in order to help writes to the database
** file run faster.
**
** <li>[[SQLITE_FCNTL_CHUNK_SIZE]]
** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
** extends and truncates the database file in chunks of a size specified
** by the user. The fourth argument to [sqlite3_file_control()] should 
** point to an integer (type int) containing the new chunk-size to use
** for the nominated database. Allocating database file space in large
** chunks (say 1MB at a time), may reduce file-system fragmentation and
** improve performance on some systems.
**
** <li>[[SQLITE_FCNTL_FILE_POINTER]]
** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer
** to the [sqlite3_file] object associated with a particular database
** connection.  See also [SQLITE_FCNTL_JOURNAL_POINTER].
**
** <li>[[SQLITE_FCNTL_JOURNAL_POINTER]]
** The [SQLITE_FCNTL_JOURNAL_POINTER] opcode is used to obtain a pointer
** to the [sqlite3_file] object associated with the journal file (either
** the [rollback journal] or the [write-ahead log]) for a particular database
** connection.  See also [SQLITE_FCNTL_FILE_POINTER].
**
** <li>[[SQLITE_FCNTL_SYNC_OMITTED]]
** No longer in use.
**
** <li>[[SQLITE_FCNTL_SYNC]]
** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and
** sent to the VFS immediately before the xSync method is invoked on a
** database file descriptor. Or, if the xSync method is not invoked 

** because the user has configured SQLite with 
** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place 
** of the xSync method. In most cases, the pointer argument passed with
** this file-control is NULL. However, if the database file is being synced
** as part of a multi-database commit, the argument points to a nul-terminated
** string containing the transactions master-journal file name. VFSes that 
** do not need this signal should silently ignore this opcode. Applications 
** should not call [sqlite3_file_control()] with this opcode as doing so may 
** disrupt the operation of the specialized VFSes that do require it.  
**
** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]]
** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite
** and sent to the VFS after a transaction has been committed immediately
** but before the database is unlocked. VFSes that do not need this signal
** should silently ignore this opcode. Applications should not call
** [sqlite3_file_control()] with this opcode as doing so may disrupt the 
** operation of the specialized VFSes that do require it.  
**
** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]]
** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic
** retry counts and intervals for certain disk I/O operations for the
** windows [VFS] in order to provide robustness in the presence of
** anti-virus programs.  By default, the windows VFS will retry file read,
** file write, and file delete operations up to 10 times, with a delay

** [sqlite3_malloc()] and the result is stored in the char* variable
** that the fourth parameter of [sqlite3_file_control()] points to.
** The caller is responsible for freeing the memory when done.  As with
** all file-control actions, there is no guarantee that this will actually
** do anything.  Callers should initialize the char* variable to a NULL
** pointer in case this file-control is not implemented.  This file-control
** is intended for diagnostic use only.
**
** <li>[[SQLITE_FCNTL_VFS_POINTER]]
** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level
** [VFSes] currently in use.  ^(The argument X in
** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be
** of type "[sqlite3_vfs] **".  This opcodes will set *X
** to a pointer to the top-level VFS.)^
** ^When there are multiple VFS shims in the stack, this opcode finds the
** upper-most shim only.
**
** <li>[[SQLITE_FCNTL_PRAGMA]]
** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA] 
** file control is sent to the open [sqlite3_file] object corresponding
** to the database file to which the pragma statement refers. ^The argument
** to the [SQLITE_FCNTL_PRAGMA] file control is an array of
** pointers to strings (char**) in which the second element of the array
** is the name of the pragma and the third element is the argument to the
** pragma or NULL if the pragma has no argument.  ^The handler for an
** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element
** of the char** argument point to a string obtained from [sqlite3_mprintf()]
** or the equivalent and that string will become the result of the pragma or
** the error message if the pragma fails. ^If the
** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal 
** [PRAGMA] processing continues.  ^If the [SQLITE_FCNTL_PRAGMA]
** file control returns [SQLITE_OK], then the parser assumes that the
** VFS has handled the PRAGMA itself and the parser generates a no-op
** prepared statement if result string is NULL, or that returns a copy
** of the result string if the string is non-NULL.
** ^If the [SQLITE_FCNTL_PRAGMA] file control returns
** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means
** that the VFS encountered an error while handling the [PRAGMA] and the
** compilation of the PRAGMA fails with an error.  ^The [SQLITE_FCNTL_PRAGMA]
** file control occurs at the beginning of pragma statement analysis and so
** it is able to override built-in [PRAGMA] statements.
**
** <li>[[SQLITE_FCNTL_BUSYHANDLER]]
** ^The [SQLITE_FCNTL_BUSYHANDLER]
** file-control may be invoked by SQLite on the database file handle
** shortly after it is opened in order to provide a custom VFS with access
** to the connections busy-handler callback. The argument is of type (void **)
** - an array of two (void *) values. The first (void *) actually points
** to a function of type (int (*)(void *)). In order to invoke the connections
** busy-handler, this function should be invoked with the second (void *) in
** the array as the only argument. If it returns non-zero, then the operation
** should be retried. If it returns zero, the custom VFS should abandon the
** current operation.
**
** <li>[[SQLITE_FCNTL_TEMPFILENAME]]
** ^Application can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control
** to have SQLite generate a
** temporary filename using the same algorithm that is followed to generate
** temporary filenames for TEMP tables and other internal uses.  The
** argument should be a char** which will be filled with the filename
** written into memory obtained from [sqlite3_malloc()].  The caller should
** invoke [sqlite3_free()] on the result to avoid a memory leak.
**
** <li>[[SQLITE_FCNTL_MMAP_SIZE]]
** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the
** maximum number of bytes that will be used for memory-mapped I/O.
** The argument is a pointer to a value of type sqlite3_int64 that
** is an advisory maximum number of bytes in the file to memory map.  The
** pointer is overwritten with the old value.  The limit is not changed if
** the value originally pointed to is negative, and so the current limit 
** can be queried by passing in a pointer to a negative number.  This
** file-control is used internally to implement [PRAGMA mmap_size].
**
** <li>[[SQLITE_FCNTL_TRACE]]
** The [SQLITE_FCNTL_TRACE] file control provides advisory information
** to the VFS about what the higher layers of the SQLite stack are doing.
** This file control is used by some VFS activity tracing [shims].
** The argument is a zero-terminated string.  Higher layers in the
** SQLite stack may generate instances of this file control if
** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled.
**
** <li>[[SQLITE_FCNTL_HAS_MOVED]]
** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a
** pointer to an integer and it writes a boolean into that integer depending
** on whether or not the file has been renamed, moved, or deleted since it
** was first opened.
**
** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]]
** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging.  This
** opcode causes the xFileControl method to swap the file handle with the one
** pointed to by the pArg argument.  This capability is used during testing
** and only needs to be supported when SQLITE_TEST is defined.
**
** <li>[[SQLITE_FCNTL_WAL_BLOCK]]
** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might
** be advantageous to block on the next WAL lock if the lock is not immediately
** available.  The WAL subsystem issues this signal during rare
** circumstances in order to fix a problem with priority inversion.
** Applications should <em>not</em> use this file-control.
**
** <li>[[SQLITE_FCNTL_ZIPVFS]]
** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other
** VFS should return SQLITE_NOTFOUND for this opcode.
**
** <li>[[SQLITE_FCNTL_RBU]]
** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by
** the RBU extension only.  All other VFS should return SQLITE_NOTFOUND for
** this opcode.  
** </ul>
*/
#define SQLITE_FCNTL_LOCKSTATE               1
#define SQLITE_FCNTL_GET_LOCKPROXYFILE       2
#define SQLITE_FCNTL_SET_LOCKPROXYFILE       3
#define SQLITE_FCNTL_LAST_ERRNO              4
#define SQLITE_FCNTL_SIZE_HINT               5
#define SQLITE_FCNTL_CHUNK_SIZE              6
#define SQLITE_FCNTL_FILE_POINTER            7
#define SQLITE_FCNTL_SYNC_OMITTED            8
#define SQLITE_FCNTL_WIN32_AV_RETRY          9
#define SQLITE_FCNTL_PERSIST_WAL            10
#define SQLITE_FCNTL_OVERWRITE              11
#define SQLITE_FCNTL_VFSNAME                12
#define SQLITE_FCNTL_POWERSAFE_OVERWRITE    13
#define SQLITE_FCNTL_PRAGMA                 14
#define SQLITE_FCNTL_BUSYHANDLER            15
#define SQLITE_FCNTL_TEMPFILENAME           16
#define SQLITE_FCNTL_MMAP_SIZE              18
#define SQLITE_FCNTL_TRACE                  19
#define SQLITE_FCNTL_HAS_MOVED              20
#define SQLITE_FCNTL_SYNC                   21
#define SQLITE_FCNTL_COMMIT_PHASETWO        22
#define SQLITE_FCNTL_WIN32_SET_HANDLE       23
#define SQLITE_FCNTL_WAL_BLOCK              24
#define SQLITE_FCNTL_ZIPVFS                 25
#define SQLITE_FCNTL_RBU                    26
#define SQLITE_FCNTL_VFS_POINTER            27
#define SQLITE_FCNTL_JOURNAL_POINTER        28

/* deprecated names */
#define SQLITE_GET_LOCKPROXYFILE      SQLITE_FCNTL_GET_LOCKPROXYFILE
#define SQLITE_SET_LOCKPROXYFILE      SQLITE_FCNTL_SET_LOCKPROXYFILE
#define SQLITE_LAST_ERRNO             SQLITE_FCNTL_LAST_ERRNO


/*
** CAPI3REF: Mutex Handle
**
** The mutex module within SQLite defines [sqlite3_mutex] to be an
** abstract type for a mutex object.  The SQLite core never looks
** at the internal representation of an [sqlite3_mutex].  It only
** deals with pointers to the [sqlite3_mutex] object.
**
** Mutexes are created using [sqlite3_mutex_alloc()].
*/
typedef struct sqlite3_mutex sqlite3_mutex;

/*
** CAPI3REF: Loadable Extension Thunk
**
** A pointer to the opaque sqlite3_api_routines structure is passed as
** the third parameter to entry points of [loadable extensions].  This
** structure must be typedefed in order to work around compiler warnings
** on some platforms.
*/
typedef struct sqlite3_api_routines sqlite3_api_routines;

/*
** CAPI3REF: OS Interface Object
**
** An instance of the sqlite3_vfs object defines the interface between
** the SQLite core and the underlying operating system.  The "vfs"
** in the name of the object stands for "virtual file system".  See
** the [VFS | VFS documentation] for further information.

  ** Those below are for version 3 and greater.
  */
  int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr);
  sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName);
  const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName);
  /*
  ** The methods above are in versions 1 through 3 of the sqlite_vfs object.
  ** New fields may be appended in future versions.  The iVersion
  ** value will increment whenever this happens. 
  */
};

/*
** CAPI3REF: Flags for the xAccess VFS method
**

** <li>  SQLITE_SHM_LOCK | SQLITE_SHM_SHARED
** <li>  SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE
** <li>  SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED
** <li>  SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE
** </ul>
**
** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as
** was given on the corresponding lock.  
**
** The xShmLock method can transition between unlocked and SHARED or
** between unlocked and EXCLUSIVE.  It cannot transition between SHARED
** and EXCLUSIVE.
*/
#define SQLITE_SHM_UNLOCK       1
#define SQLITE_SHM_LOCK         2

**
** The sqlite3_config() interface is used to make global configuration
** changes to SQLite in order to tune SQLite to the specific needs of
** the application.  The default configuration is recommended for most
** applications and so this routine is usually not necessary.  It is
** provided to support rare applications with unusual needs.
**
** <b>The sqlite3_config() interface is not threadsafe. The application
** must ensure that no other SQLite interfaces are invoked by other
** threads while sqlite3_config() is running.</b>
**
** The sqlite3_config() interface
** may only be invoked prior to library initialization using
** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
** [sqlite3_shutdown()] then it will return SQLITE_MISUSE.
** Note, however, that ^sqlite3_config() can be called as part of the
** implementation of an application-defined [sqlite3_os_init()].
**

** ^If the option is unknown or SQLite is unable to set the option
** then this routine returns a non-zero [error code].
*/
SQLITE_API int sqlite3_config(int, ...);

/*
** CAPI3REF: Configure database connections
** METHOD: sqlite3
**
** The sqlite3_db_config() interface is used to make configuration
** changes to a [database connection].  The interface is similar to
** [sqlite3_config()] except that the changes apply to a single
** [database connection] (specified in the first argument).
**
** The second argument to sqlite3_db_config(D,V,...)  is the

** a memory allocation given a particular requested size.  Most memory
** allocators round up memory allocations at least to the next multiple
** of 8.  Some allocators round up to a larger multiple or to a power of 2.
** Every memory allocation request coming in through [sqlite3_malloc()]
** or [sqlite3_realloc()] first calls xRoundup.  If xRoundup returns 0, 
** that causes the corresponding memory allocation to fail.
**
** The xInit method initializes the memory allocator.  For example,
** it might allocate any require mutexes or initialize internal data
** structures.  The xShutdown method is invoked (indirectly) by
** [sqlite3_shutdown()] and should deallocate any resources acquired
** by xInit.  The pAppData pointer is used as the only parameter to
** xInit and xShutdown.
**
** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes

** ^If SQLite is compiled with
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
** it is not possible to set the Serialized [threading mode] and
** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
** SQLITE_CONFIG_SERIALIZED configuration option.</dd>
**
** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt>
** <dd> ^(The SQLITE_CONFIG_MALLOC option takes a single argument which is 
** a pointer to an instance of the [sqlite3_mem_methods] structure.
** The argument specifies
** alternative low-level memory allocation routines to be used in place of
** the memory allocation routines built into SQLite.)^ ^SQLite makes
** its own private copy of the content of the [sqlite3_mem_methods] structure
** before the [sqlite3_config()] call returns.</dd>
**
** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt>
** <dd> ^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which
** is a pointer to an instance of the [sqlite3_mem_methods] structure.
** The [sqlite3_mem_methods]
** structure is filled with the currently defined memory allocation routines.)^
** This option can be used to overload the default memory allocation
** routines with a wrapper that simulations memory allocation failure or
** tracks memory usage, for example. </dd>
**
** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt>
** <dd> ^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int,
** interpreted as a boolean, which enables or disables the collection of
** memory allocation statistics. ^(When memory allocation statistics are
** disabled, the following SQLite interfaces become non-operational:
**   <ul>
**   <li> [sqlite3_memory_used()]
**   <li> [sqlite3_memory_highwater()]
**   <li> [sqlite3_soft_heap_limit64()]
**   <li> [sqlite3_status64()]
**   </ul>)^
** ^Memory allocation statistics are enabled by default unless SQLite is
** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
** allocation statistics are disabled by default.
** </dd>
**
** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt>
** <dd> ^The SQLITE_CONFIG_SCRATCH option specifies a static memory buffer
** that SQLite can use for scratch memory.  ^(There are three arguments
** to SQLITE_CONFIG_SCRATCH:  A pointer an 8-byte
** aligned memory buffer from which the scratch allocations will be
** drawn, the size of each scratch allocation (sz),
** and the maximum number of scratch allocations (N).)^

** The first argument must be a pointer to an 8-byte aligned buffer
** of at least sz*N bytes of memory.
** ^SQLite will not use more than one scratch buffers per thread.

** ^SQLite will never request a scratch buffer that is more than 6
** times the database page size.
** ^If SQLite needs needs additional
** scratch memory beyond what is provided by this configuration option, then 
** [sqlite3_malloc()] will be used to obtain the memory needed.<p>
** ^When the application provides any amount of scratch memory using
** SQLITE_CONFIG_SCRATCH, SQLite avoids unnecessary large
** [sqlite3_malloc|heap allocations].
** This can help [Robson proof|prevent memory allocation failures] due to heap
** fragmentation in low-memory embedded systems.
** </dd>
**
** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt>
** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool
** that SQLite can use for the database page cache with the default page
** cache implementation.  
** This configuration option is a no-op if an application-define page
** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2].
** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to
** 8-byte aligned memory (pMem), the size of each page cache line (sz),
** and the number of cache lines (N).
** The sz argument should be the size of the largest database page
** (a power of two between 512 and 65536) plus some extra bytes for each
** page header.  ^The number of extra bytes needed by the page header
** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ].
** ^It is harmless, apart from the wasted memory,
** for the sz parameter to be larger than necessary.  The pMem
** argument must be either a NULL pointer or a pointer to an 8-byte
** aligned block of memory of at least sz*N bytes, otherwise
** subsequent behavior is undefined.
** ^When pMem is not NULL, SQLite will strive to use the memory provided
** to satisfy page cache needs, falling back to [sqlite3_malloc()] if
** a page cache line is larger than sz bytes or if all of the pMem buffer
** is exhausted.
** ^If pMem is NULL and N is non-zero, then each database connection
** does an initial bulk allocation for page cache memory
** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or
** of -1024*N bytes if N is negative, . ^If additional
** page cache memory is needed beyond what is provided by the initial
** allocation, then SQLite goes to [sqlite3_malloc()] separately for each


** additional cache line. </dd>
**
** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt>
** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer 
** that SQLite will use for all of its dynamic memory allocation needs
** beyond those provided for by [SQLITE_CONFIG_SCRATCH] and
** [SQLITE_CONFIG_PAGECACHE].
** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled
** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns
** [SQLITE_ERROR] if invoked otherwise.
** ^There are three arguments to SQLITE_CONFIG_HEAP:
** An 8-byte aligned pointer to the memory,
** the number of bytes in the memory buffer, and the minimum allocation size.
** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
** to using its default memory allocator (the system malloc() implementation),
** undoing any prior invocation of [SQLITE_CONFIG_MALLOC].  ^If the
** memory pointer is not NULL then the alternative memory

** allocator is engaged to handle all of SQLites memory allocation needs.
** The first pointer (the memory pointer) must be aligned to an 8-byte
** boundary or subsequent behavior of SQLite will be undefined.
** The minimum allocation size is capped at 2**12. Reasonable values
** for the minimum allocation size are 2**5 through 2**8.</dd>
**
** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt>
** <dd> ^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a
** pointer to an instance of the [sqlite3_mutex_methods] structure.
** The argument specifies alternative low-level mutex routines to be used
** in place the mutex routines built into SQLite.)^  ^SQLite makes a copy of
** the content of the [sqlite3_mutex_methods] structure before the call to
** [sqlite3_config()] returns. ^If SQLite is compiled with
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
** the entire mutexing subsystem is omitted from the build and hence calls to
** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
** return [SQLITE_ERROR].</dd>
**
** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt>
** <dd> ^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which
** is a pointer to an instance of the [sqlite3_mutex_methods] structure.  The
** [sqlite3_mutex_methods]
** structure is filled with the currently defined mutex routines.)^
** This option can be used to overload the default mutex allocation
** routines with a wrapper used to track mutex usage for performance
** profiling or testing, for example.   ^If SQLite is compiled with
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
** the entire mutexing subsystem is omitted from the build and hence calls to
** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
** return [SQLITE_ERROR].</dd>
**
** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt>
** <dd> ^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine
** the default size of lookaside memory on each [database connection].
** The first argument is the
** size of each lookaside buffer slot and the second is the number of
** slots allocated to each database connection.)^  ^(SQLITE_CONFIG_LOOKASIDE
** sets the <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]
** option to [sqlite3_db_config()] can be used to change the lookaside
** configuration on individual connections.)^ </dd>
**
** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt>
** <dd> ^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is 
** a pointer to an [sqlite3_pcache_methods2] object.  This object specifies
** the interface to a custom page cache implementation.)^
** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.</dd>
**
** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt>
** <dd> ^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which
** is a pointer to an [sqlite3_pcache_methods2] object.  SQLite copies of
** the current page cache implementation into that object.)^ </dd>
**
** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt>
** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite
** global [error log].
** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
** function with a call signature of void(*)(void*,int,const char*), 
** and a pointer to void. ^If the function pointer is not NULL, it is
** invoked by [sqlite3_log()] to process each logging event.  ^If the
** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
** passed through as the first parameter to the application-defined logger
** function whenever that function is invoked.  ^The second parameter to
** the logger function is a copy of the first parameter to the corresponding
** [sqlite3_log()] call and is intended to be a [result code] or an
** [extended result code].  ^The third parameter passed to the logger is
** 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>^(The SQLITE_CONFIG_URI 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>^The SQLITE_CONFIG_COVERING_INDEX_SCAN 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.
** </dd>
**
** [[SQLITE_CONFIG_SQLLOG]]
** <dt>SQLITE_CONFIG_SQLLOG
** <dd>This option is only available if sqlite is compiled with the
** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should
** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int).
** The second should be of type (void*). The callback is invoked by the library
** in three separate circumstances, identified by the value passed as the
** fourth parameter. If the fourth parameter is 0, then the database connection
** passed as the second argument has just been opened. The third argument
** points to a buffer containing the name of the main database file. If the
** fourth parameter is 1, then the SQL statement that the third parameter
** points to has just been executed. Or, if the fourth parameter is 2, then
** 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
** will be silently truncated if necessary so that it does not 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.
**
** [[SQLITE_CONFIG_WIN32_HEAPSIZE]]
** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE
** <dd>^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is
** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro
** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value
** that specifies the maximum size of the created heap.
**
** [[SQLITE_CONFIG_PCACHE_HDRSZ]]
** <dt>SQLITE_CONFIG_PCACHE_HDRSZ
** <dd>^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which
** is a pointer to an integer and writes into that integer the number of extra
** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE].
** The amount of extra space required can change depending on the compiler,
** target platform, and SQLite version.
**
** [[SQLITE_CONFIG_PMASZ]]
** <dt>SQLITE_CONFIG_PMASZ
** <dd>^The SQLITE_CONFIG_PMASZ option takes a single parameter which
** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded
** sorter to that integer.  The default minimum PMA Size is set by the
** [SQLITE_SORTER_PMASZ] compile-time option.  New threads are launched
** to help with sort operations when multithreaded sorting
** is enabled (using the [PRAGMA threads] command) and the amount of content
** to be sorted exceeds the page size times the minimum of the
** [PRAGMA cache_size] setting and this value.
**
** [[SQLITE_CONFIG_STMTJRNL_SPILL]]
** <dt>SQLITE_CONFIG_STMTJRNL_SPILL
** <dd>^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which
** becomes the [statement journal] spill-to-disk threshold.  
** [Statement journals] are held in memory until their size (in bytes)
** exceeds this threshold, at which point they are written to disk.
** Or if the threshold is -1, statement journals are always held
** exclusively in memory.
** Since many statement journals never become large, setting the spill
** threshold to a value such as 64KiB can greatly reduce the amount of
** I/O required to support statement rollback.
** The default value for this setting is controlled by the
** [SQLITE_STMTJRNL_SPILL] compile-time option.
** </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* */
#define SQLITE_CONFIG_GETMALLOC     5  /* sqlite3_mem_methods* */

#define SQLITE_CONFIG_GETPCACHE    15  /* no-op */
#define SQLITE_CONFIG_LOG          16  /* xFunc, void* */
#define SQLITE_CONFIG_URI          17  /* int */
#define SQLITE_CONFIG_PCACHE2      18  /* sqlite3_pcache_methods2* */
#define SQLITE_CONFIG_GETPCACHE2   19  /* sqlite3_pcache_methods2* */
#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20  /* int */
#define SQLITE_CONFIG_SQLLOG       21  /* xSqllog, void* */
#define SQLITE_CONFIG_MMAP_SIZE    22  /* sqlite3_int64, sqlite3_int64 */
#define SQLITE_CONFIG_WIN32_HEAPSIZE      23  /* int nByte */
#define SQLITE_CONFIG_PCACHE_HDRSZ        24  /* int *psz */
#define SQLITE_CONFIG_PMASZ               25  /* unsigned int szPma */
#define SQLITE_CONFIG_STMTJRNL_SPILL      26  /* int nByte */

/*
** CAPI3REF: Database Connection Configuration Options
**
** These constants are the available integer configuration options that
** can be passed as the second argument to the [sqlite3_db_config()] interface.
**

** The first argument is an integer which is 0 to disable triggers,
** positive to enable triggers or negative to leave the setting unchanged.
** The second parameter is a pointer to an integer into which
** is written 0 or 1 to indicate whether triggers are disabled or enabled
** following this call.  The second parameter may be a NULL pointer, in
** which case the trigger setting is not reported back. </dd>
**
** <dt>SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER</dt>
** <dd> ^This option is used to enable or disable the two-argument
** version of the [fts3_tokenizer()] function which is part of the
** [FTS3] full-text search engine extension.
** There should be two additional arguments.
** The first argument is an integer which is 0 to disable fts3_tokenizer() or
** positive to enable fts3_tokenizer() or negative to leave the setting
** unchanged.
** The second parameter is a pointer to an integer into which
** is written 0 or 1 to indicate whether fts3_tokenizer is disabled or enabled
** following this call.  The second parameter may be a NULL pointer, in
** which case the new setting is not reported back. </dd>
**
** <dt>SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION</dt>
** <dd> ^This option is used to enable or disable the [sqlite3_load_extension()]
** interface independently of the [load_extension()] SQL function.
** The [sqlite3_enable_load_extension()] API enables or disables both the
** C-API [sqlite3_load_extension()] and the SQL function [load_extension()].
** There should be two additional arguments.
** When the first argument to this interface is 1, then only the C-API is
** enabled and the SQL function remains disabled.  If the first argument to
** this interface is 0, then both the C-API and the SQL function are disabled.
** If the first argument is -1, then no changes are made to state of either the
** C-API or the SQL function.
** The second parameter is a pointer to an integer into which
** is written 0 or 1 to indicate whether [sqlite3_load_extension()] interface
** is disabled or enabled following this call.  The second parameter may
** be a NULL pointer, in which case the new setting is not reported back.
** </dd>
**
** <dt>SQLITE_DBCONFIG_MAINDBNAME</dt>
** <dd> ^This option is used to change the name of the "main" database
** schema.  ^The sole argument is a pointer to a constant UTF8 string
** which will become the new schema name in place of "main".  ^SQLite
** does not make a copy of the new main schema name string, so the application
** must ensure that the argument passed into this DBCONFIG option is unchanged
** until after the database connection closes.
** </dd>
**
** </dl>
*/
#define SQLITE_DBCONFIG_MAINDBNAME            1000 /* const char* */
#define SQLITE_DBCONFIG_LOOKASIDE             1001 /* void* int int */
#define SQLITE_DBCONFIG_ENABLE_FKEY           1002 /* int int* */
#define SQLITE_DBCONFIG_ENABLE_TRIGGER        1003 /* int int* */
#define SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER 1004 /* int int* */
#define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* */


/*
** CAPI3REF: Enable Or Disable Extended Result Codes
** METHOD: sqlite3
**
** ^The sqlite3_extended_result_codes() routine enables or disables the
** [extended result codes] feature of SQLite. ^The extended result
** codes are disabled by default for historical compatibility.
*/
SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff);

/*
** CAPI3REF: Last Insert Rowid
** METHOD: sqlite3
**
** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables)
** has a unique 64-bit signed
** integer key called the [ROWID | "rowid"]. ^The rowid is always available
** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
** names are not also used by explicitly declared columns. ^If
** the table has a column of type [INTEGER PRIMARY KEY] then that column
** is another alias for the rowid.
**
** ^The sqlite3_last_insert_rowid(D) interface returns the [rowid] of the 
** most recent successful [INSERT] into a rowid table or [virtual table]
** on database connection D.
** ^Inserts into [WITHOUT ROWID] tables are not recorded.
** ^If no successful [INSERT]s into rowid tables
** have ever occurred on the database connection D, 
** then sqlite3_last_insert_rowid(D) returns zero.
**
** ^(If an [INSERT] occurs within a trigger or within a [virtual table]
** method, then this routine will return the [rowid] of the inserted
** row as long as the trigger or virtual table method is running.
** But once the trigger or virtual table method ends, the value returned 
** by this routine reverts to what it was before the trigger or virtual
** table method began.)^

** unpredictable and might not equal either the old or the new
** last insert [rowid].
*/
SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);

/*
** CAPI3REF: Count The Number Of Rows Modified
** METHOD: sqlite3
**
** ^This function returns the number of rows modified, inserted or
** deleted by the most recently completed INSERT, UPDATE or DELETE
** statement on the database connection specified by the only parameter.

** ^Executing any other type of SQL statement does not modify the value

** returned by this function.

**
** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are
** considered - auxiliary changes caused by [CREATE TRIGGER | triggers], 



** [foreign key actions] or [REPLACE] constraint resolution are not counted.


** 
** Changes to a view that are intercepted by 
** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value 

** returned by sqlite3_changes() immediately after an INSERT, UPDATE or 
** DELETE statement run on a view is always zero. Only changes made to real 
** tables are counted.
**
** Things are more complicated if the sqlite3_changes() function is
** executed while a trigger program is running. This may happen if the
** program uses the [changes() SQL function], or if some other callback
** function invokes sqlite3_changes() directly. Essentially:
** 

** <ul>
**   <li> ^(Before entering a trigger program the value returned by
**        sqlite3_changes() function is saved. After the trigger program 
**        has finished, the original value is restored.)^
** 

**   <li> ^(Within a trigger program each INSERT, UPDATE and DELETE 
**        statement sets the value returned by sqlite3_changes() 
**        upon completion as normal. Of course, this value will not include 
**        any changes performed by sub-triggers, as the sqlite3_changes() 
**        value will be saved and restored after each sub-trigger has run.)^
** </ul>
** 



** ^This means that if the changes() SQL function (or similar) is used
** by the first INSERT, UPDATE or DELETE statement within a trigger, it 
** returns the value as set when the calling statement began executing.
** ^If it is used by the second or subsequent such statement within a trigger 
** program, the value returned reflects the number of rows modified by the 
** previous INSERT, UPDATE or DELETE statement within the same trigger.


**
** See also the [sqlite3_total_changes()] interface, the
** [count_changes pragma], and the [changes() SQL function].
**
** If a separate thread makes changes on the same database connection
** while [sqlite3_changes()] is running then the value returned
** is unpredictable and not meaningful.
*/
SQLITE_API int sqlite3_changes(sqlite3*);

/*
** CAPI3REF: Total Number Of Rows Modified
** METHOD: sqlite3
**
** ^This function returns the total number of rows inserted, modified or
** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed
** since the database connection was opened, including those executed as
** part of trigger programs. ^Executing any other type of SQL statement
** does not affect the value returned by sqlite3_total_changes().

** 
** ^Changes made as part of [foreign key actions] are included in the


** count, but those made as part of REPLACE constraint resolution are
** not. ^Changes to a view that are intercepted by INSTEAD OF triggers 
** are not counted.



** 
** See also the [sqlite3_changes()] interface, the
** [count_changes pragma], and the [total_changes() SQL function].
**
** If a separate thread makes changes on the same database connection
** while [sqlite3_total_changes()] is running then the value
** returned is unpredictable and not meaningful.
*/
SQLITE_API int sqlite3_total_changes(sqlite3*);

/*
** CAPI3REF: Interrupt A Long-Running Query
** METHOD: sqlite3
**
** ^This function causes any pending database operation to abort and
** return at its earliest opportunity. This routine is typically
** called in response to a user action such as pressing "Cancel"
** or Ctrl-C where the user wants a long query operation to halt
** immediately.
**

** UTF-16 string in native byte order.
*/
SQLITE_API int sqlite3_complete(const char *sql);
SQLITE_API int sqlite3_complete16(const void *sql);

/*
** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
** KEYWORDS: {busy-handler callback} {busy handler}
** METHOD: sqlite3
**
** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X
** that might be invoked with argument P whenever
** an attempt is made to access a database table associated with
** [database connection] D when another thread
** or process has the table locked.
** The sqlite3_busy_handler() interface is used to implement
** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout].
**
** ^If the busy callback is NULL, then [SQLITE_BUSY]
** is returned immediately upon encountering the lock.  ^If the busy callback
** is not NULL, then the callback might be invoked with two arguments.
**
** ^The first argument to the busy handler is a copy of the void* pointer which
** is the third argument to sqlite3_busy_handler().  ^The second argument to
** the busy handler callback is the number of times that the busy handler has
** been invoked previously for the same locking event.  ^If the
** busy callback returns 0, then no additional attempts are made to
** access the database and [SQLITE_BUSY] is returned
** to the application.
** ^If the callback returns non-zero, then another attempt
** is made to access the database and the cycle repeats.
**
** The presence of a busy handler does not guarantee that it will be invoked
** when there is lock contention. ^If SQLite determines that invoking the busy
** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
** to the application instead of invoking the 
** busy handler.
** Consider a scenario where one process is holding a read lock that
** it is trying to promote to a reserved lock and
** a second process is holding a reserved lock that it is trying
** to promote to an exclusive lock.  The first process cannot proceed
** because it is blocked by the second and the second process cannot
** proceed because it is blocked by the first.  If both processes
** invoke the busy handlers, neither will make any progress.  Therefore,
** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
** will induce the first process to release its read lock and allow
** the second process to proceed.
**
** ^The default busy callback is NULL.
**















** ^(There can only be a single busy handler defined for each
** [database connection].  Setting a new busy handler clears any
** previously set handler.)^  ^Note that calling [sqlite3_busy_timeout()]
** or evaluating [PRAGMA busy_timeout=N] will change the
** busy handler and thus clear any previously set busy handler.
**
** The busy callback should not take any actions which modify the
** database connection that invoked the busy handler.  In other words,
** the busy handler is not reentrant.  Any such actions
** result in undefined behavior.
** 
** A busy handler must not close the database connection
** or [prepared statement] that invoked the busy handler.
*/
SQLITE_API int sqlite3_busy_handler(sqlite3*,int(*)(void*,int),void*);

/*
** CAPI3REF: Set A Busy Timeout
** METHOD: sqlite3
**
** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
** for a specified amount of time when a table is locked.  ^The handler
** will sleep multiple times until at least "ms" milliseconds of sleeping
** have accumulated.  ^After at least "ms" milliseconds of sleeping,
** the handler returns 0 which causes [sqlite3_step()] to return
** [SQLITE_BUSY].
**
** ^Calling this routine with an argument less than or equal to zero
** turns off all busy handlers.
**
** ^(There can only be a single busy handler for a particular
** [database connection] at any given moment.  If another busy handler
** was defined  (using [sqlite3_busy_handler()]) prior to calling
** this routine, that other busy handler is cleared.)^
**
** See also:  [PRAGMA busy_timeout]
*/
SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);

/*
** CAPI3REF: Convenience Routines For Running Queries
** METHOD: sqlite3
**
** This is a legacy interface that is preserved for backwards compatibility.
** Use of this interface is not recommended.
**
** Definition: A <b>result table</b> is memory data structure created by the
** [sqlite3_get_table()] interface.  A result table records the
** complete query results from one or more queries.

SQLITE_API void sqlite3_free_table(char **result);

/*
** CAPI3REF: Formatted String Printing Functions
**
** These routines are work-alikes of the "printf()" family of functions
** from the standard C library.
** These routines understand most of the common K&R formatting options,
** plus some additional non-standard formats, detailed below.
** Note that some of the more obscure formatting options from recent
** C-library standards are omitted from this implementation.
**
** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
** results into memory obtained from [sqlite3_malloc()].
** The strings returned by these two routines should be
** released by [sqlite3_free()].  ^Both routines return a
** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
** memory to hold the resulting string.

** written will be n-1 characters.
**
** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf().
**
** These routines all implement some additional formatting
** options that are useful for constructing SQL statements.
** All of the usual printf() formatting options apply.  In addition, there
** is are "%q", "%Q", "%w" and "%z" options.
**
** ^(The %q option works like %s in that it substitutes a nul-terminated
** string from the argument list.  But %q also doubles every '\'' character.
** %q is designed for use inside a string literal.)^  By doubling each '\''
** character it escapes that character and allows it to be inserted into
** the string.
**

**  char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
**  sqlite3_exec(db, zSQL, 0, 0, 0);
**  sqlite3_free(zSQL);
** </pre></blockquote>
**
** The code above will render a correct SQL statement in the zSQL
** variable even if the zText variable is a NULL pointer.
**
** ^(The "%w" formatting option is like "%q" except that it expects to
** be contained within double-quotes instead of single quotes, and it
** escapes the double-quote character instead of the single-quote
** character.)^  The "%w" formatting option is intended for safely inserting
** table and column names into a constructed SQL statement.
**
** ^(The "%z" formatting option works like "%s" but with the
** addition that after the string has been read and copied into
** the result, [sqlite3_free()] is called on the input string.)^
*/
SQLITE_API char *sqlite3_mprintf(const char*,...);
SQLITE_API char *sqlite3_vmprintf(const char*, va_list);

**
** ^The sqlite3_malloc() routine returns a pointer to a block
** of memory at least N bytes in length, where N is the parameter.
** ^If sqlite3_malloc() is unable to obtain sufficient free
** memory, it returns a NULL pointer.  ^If the parameter N to
** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
** a NULL pointer.
**
** ^The sqlite3_malloc64(N) routine works just like
** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead
** of a signed 32-bit integer.
**
** ^Calling sqlite3_free() with a pointer previously returned
** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
** that it might be reused.  ^The sqlite3_free() routine is
** a no-op if is called with a NULL pointer.  Passing a NULL pointer
** to sqlite3_free() is harmless.  After being freed, memory
** should neither be read nor written.  Even reading previously freed
** memory might result in a segmentation fault or other severe error.
** Memory corruption, a segmentation fault, or other severe error
** might result if sqlite3_free() is called with a non-NULL pointer that
** was not obtained from sqlite3_malloc() or sqlite3_realloc().
**
** ^The sqlite3_realloc(X,N) interface attempts to resize a
** prior memory allocation X to be at least N bytes.

** ^If the X parameter to sqlite3_realloc(X,N)
** is a NULL pointer then its behavior is identical to calling
** sqlite3_malloc(N).
** ^If the N parameter to sqlite3_realloc(X,N) is zero or
** negative then the behavior is exactly the same as calling
** sqlite3_free(X).
** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation
** of at least N bytes in size or NULL if insufficient memory is available.
** ^If M is the size of the prior allocation, then min(N,M) bytes
** of the prior allocation are copied into the beginning of buffer returned
** by sqlite3_realloc(X,N) and the prior allocation is freed.
** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the
** prior allocation is not freed.
**
** ^The sqlite3_realloc64(X,N) interfaces works the same as
** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead
** of a 32-bit signed integer.
**
** ^If X is a memory allocation previously obtained from sqlite3_malloc(),
** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then
** sqlite3_msize(X) returns the size of that memory allocation in bytes.
** ^The value returned by sqlite3_msize(X) might be larger than the number
** of bytes requested when X was allocated.  ^If X is a NULL pointer then
** sqlite3_msize(X) returns zero.  If X points to something that is not
** the beginning of memory allocation, or if it points to a formerly
** valid memory allocation that has now been freed, then the behavior
** of sqlite3_msize(X) is undefined and possibly harmful.
**
** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(),
** sqlite3_malloc64(), and sqlite3_realloc64()
** is always aligned to at least an 8 byte boundary, or to a
** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
** option is used.
**
** In SQLite version 3.5.0 and 3.5.1, it was possible to define
** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
** implementation of these routines to be omitted.  That capability

** not yet been released.
**
** The application must not read or write any part of
** a block of memory after it has been released using
** [sqlite3_free()] or [sqlite3_realloc()].
*/
SQLITE_API void *sqlite3_malloc(int);
SQLITE_API void *sqlite3_malloc64(sqlite3_uint64);
SQLITE_API void *sqlite3_realloc(void*, int);
SQLITE_API void *sqlite3_realloc64(void*, sqlite3_uint64);
SQLITE_API void sqlite3_free(void*);
SQLITE_API sqlite3_uint64 sqlite3_msize(void*);

/*
** CAPI3REF: Memory Allocator Statistics
**
** SQLite provides these two interfaces for reporting on the status
** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
** routines, which form the built-in memory allocation subsystem.

** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
** select random [ROWID | ROWIDs] when inserting new records into a table that
** already uses the largest possible [ROWID].  The PRNG is also used for
** the build-in random() and randomblob() SQL functions.  This interface allows
** applications to access the same PRNG for other purposes.
**
** ^A call to this routine stores N bytes of randomness into buffer P.
** ^The P parameter can be a NULL pointer.
**
** ^If this routine has not been previously called or if the previous
** call had N less than one or a NULL pointer for P, then the PRNG is
** seeded using randomness obtained from the xRandomness method of
** the default [sqlite3_vfs] object.
** ^If the previous call to this routine had an N of 1 or more and a
** non-NULL P then the pseudo-randomness is generated
** internally and without recourse to the [sqlite3_vfs] xRandomness
** method.
*/
SQLITE_API void sqlite3_randomness(int N, void *P);

/*
** CAPI3REF: Compile-Time Authorization Callbacks
** METHOD: sqlite3
**
** ^This routine registers an authorizer callback with a particular
** [database connection], supplied in the first argument.
** ^The authorizer callback is invoked as SQL statements are being compiled
** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()].  ^At various
** points during the compilation process, as logic is being created

**
** The [sqlite3_set_authorizer | authorizer callback function] must
** return either [SQLITE_OK] or one of these two constants in order
** to signal SQLite whether or not the action is permitted.  See the
** [sqlite3_set_authorizer | authorizer documentation] for additional
** information.
**
** Note that SQLITE_IGNORE is also used as a [conflict resolution mode]
** returned from the [sqlite3_vtab_on_conflict()] interface.
*/
#define SQLITE_DENY   1   /* Abort the SQL statement with an error */
#define SQLITE_IGNORE 2   /* Don't allow access, but don't generate an error */

/*
** CAPI3REF: Authorizer Action Codes
**

#define SQLITE_REINDEX              27   /* Index Name      NULL            */
#define SQLITE_ANALYZE              28   /* Table Name      NULL            */
#define SQLITE_CREATE_VTABLE        29   /* Table Name      Module Name     */
#define SQLITE_DROP_VTABLE          30   /* Table Name      Module Name     */
#define SQLITE_FUNCTION             31   /* NULL            Function Name   */
#define SQLITE_SAVEPOINT            32   /* Operation       Savepoint Name  */
#define SQLITE_COPY                  0   /* No longer used */
#define SQLITE_RECURSIVE            33   /* NULL            NULL            */

/*
** CAPI3REF: Tracing And Profiling Functions
** METHOD: sqlite3
**
** These routines are deprecated. Use the [sqlite3_trace_v2()] interface
** instead of the routines described here.
**
** These routines register callback functions that can be used for
** tracing and profiling the execution of SQL statements.
**
** ^The callback function registered by sqlite3_trace() is invoked at
** various times when an SQL statement is being run by [sqlite3_step()].
** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
** SQL statement text as the statement first begins executing.
** ^(Additional sqlite3_trace() callbacks might occur
** as each triggered subprogram is entered.  The callbacks for triggers
** contain a UTF-8 SQL comment that identifies the trigger.)^
**
** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit
** the length of [bound parameter] expansion in the output of sqlite3_trace().
**
** ^The callback function registered by sqlite3_profile() is invoked
** as each SQL statement finishes.  ^The profile callback contains
** the original statement text and an estimate of wall-clock time
** of how long that statement took to run.  ^The profile callback
** time is in units of nanoseconds, however the current implementation
** is only capable of millisecond resolution so the six least significant
** digits in the time are meaningless.  Future versions of SQLite
** might provide greater resolution on the profiler callback.  The
** sqlite3_profile() function is considered experimental and is
** subject to change in future versions of SQLite.
*/
SQLITE_API SQLITE_DEPRECATED void *sqlite3_trace(sqlite3*,
   void(*xTrace)(void*,const char*), void*);
SQLITE_API SQLITE_DEPRECATED void *sqlite3_profile(sqlite3*,
   void(*xProfile)(void*,const char*,sqlite3_uint64), void*);

/*
** CAPI3REF: SQL Trace Event Codes
** KEYWORDS: SQLITE_TRACE
**
** These constants identify classes of events that can be monitored
** using the [sqlite3_trace_v2()] tracing logic.  The third argument
** to [sqlite3_trace_v2()] is an OR-ed combination of one or more of
** the following constants.  ^The first argument to the trace callback
** is one of the following constants.
**
** New tracing constants may be added in future releases.
**
** ^A trace callback has four arguments: xCallback(T,C,P,X).
** ^The T argument is one of the integer type codes above.
** ^The C argument is a copy of the context pointer passed in as the
** fourth argument to [sqlite3_trace_v2()].
** The P and X arguments are pointers whose meanings depend on T.
**
** <dl>
** [[SQLITE_TRACE_STMT]] <dt>SQLITE_TRACE_STMT</dt>
** <dd>^An SQLITE_TRACE_STMT callback is invoked when a prepared statement
** first begins running and possibly at other times during the
** execution of the prepared statement, such as at the start of each
** trigger subprogram. ^The P argument is a pointer to the
** [prepared statement]. ^The X argument is a pointer to a string which
** is the unexpanded SQL text of the prepared statement or an SQL comment 
** that indicates the invocation of a trigger.  ^The callback can compute
** the same text that would have been returned by the legacy [sqlite3_trace()]
** interface by using the X argument when X begins with "--" and invoking
** [sqlite3_expanded_sql(P)] otherwise.
**
** [[SQLITE_TRACE_PROFILE]] <dt>SQLITE_TRACE_PROFILE</dt>
** <dd>^An SQLITE_TRACE_PROFILE callback provides approximately the same
** information as is provided by the [sqlite3_profile()] callback.
** ^The P argument is a pointer to the [prepared statement] and the
** X argument points to a 64-bit integer which is the estimated of
** the number of nanosecond that the prepared statement took to run.
** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes.
**
** [[SQLITE_TRACE_ROW]] <dt>SQLITE_TRACE_ROW</dt>
** <dd>^An SQLITE_TRACE_ROW callback is invoked whenever a prepared
** statement generates a single row of result.  
** ^The P argument is a pointer to the [prepared statement] and the
** X argument is unused.
**
** [[SQLITE_TRACE_CLOSE]] <dt>SQLITE_TRACE_CLOSE</dt>
** <dd>^An SQLITE_TRACE_CLOSE callback is invoked when a database
** connection closes.
** ^The P argument is a pointer to the [database connection] object
** and the X argument is unused.
** </dl>
*/
#define SQLITE_TRACE_STMT       0x01
#define SQLITE_TRACE_PROFILE    0x02
#define SQLITE_TRACE_ROW        0x04
#define SQLITE_TRACE_CLOSE      0x08

/*
** CAPI3REF: SQL Trace Hook
** METHOD: sqlite3
**
** ^The sqlite3_trace_v2(D,M,X,P) interface registers a trace callback
** function X against [database connection] D, using property mask M
** and context pointer P.  ^If the X callback is
** NULL or if the M mask is zero, then tracing is disabled.  The
** M argument should be the bitwise OR-ed combination of
** zero or more [SQLITE_TRACE] constants.
**
** ^Each call to either sqlite3_trace() or sqlite3_trace_v2() overrides 
** (cancels) any prior calls to sqlite3_trace() or sqlite3_trace_v2().
**
** ^The X callback is invoked whenever any of the events identified by 
** mask M occur.  ^The integer return value from the callback is currently
** ignored, though this may change in future releases.  Callback
** implementations should return zero to ensure future compatibility.
**
** ^A trace callback is invoked with four arguments: callback(T,C,P,X).
** ^The T argument is one of the [SQLITE_TRACE]
** constants to indicate why the callback was invoked.
** ^The C argument is a copy of the context pointer.
** The P and X arguments are pointers whose meanings depend on T.
**
** The sqlite3_trace_v2() interface is intended to replace the legacy
** interfaces [sqlite3_trace()] and [sqlite3_profile()], both of which
** are deprecated.
*/
SQLITE_API int sqlite3_trace_v2(
  sqlite3*,
  unsigned uMask,
  int(*xCallback)(unsigned,void*,void*,void*),
  void *pCtx
);

/*
** CAPI3REF: Query Progress Callbacks
** METHOD: sqlite3
**
** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
** function X to be invoked periodically during long running calls to
** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for
** database connection D.  An example use for this
** interface is to keep a GUI updated during a large query.
**
** ^The parameter P is passed through as the only parameter to the 
** callback function X.  ^The parameter N is the approximate number of 
** [virtual machine instructions] that are evaluated between successive
** invocations of the callback X.  ^If N is less than one then the progress
** handler is disabled.
**
** ^Only a single progress handler may be defined at one time per
** [database connection]; setting a new progress handler cancels the
** old one.  ^Setting parameter X to NULL disables the progress handler.
** ^The progress handler is also disabled by setting N to a value less
** than 1.
**

** database connections for the meaning of "modify" in this paragraph.
**
*/
SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);

/*
** CAPI3REF: Opening A New Database Connection
** CONSTRUCTOR: sqlite3
**
** ^These routines open an SQLite database file as specified by the 
** filename argument. ^The filename argument is interpreted as UTF-8 for
** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
** order for sqlite3_open16(). ^(A [database connection] handle is usually
** returned in *ppDb, even if an error occurs.  The only exception is that
** if SQLite is unable to allocate memory to hold the [sqlite3] object,
** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
** object.)^ ^(If the database is opened (and/or created) successfully, then
** [SQLITE_OK] is returned.  Otherwise an [error code] is returned.)^ ^The
** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
** an English language description of the error following a failure of any
** of the sqlite3_open() routines.
**
** ^The default encoding will be UTF-8 for databases created using
** sqlite3_open() or sqlite3_open_v2().  ^The default encoding for databases
** created using sqlite3_open16() will be UTF-16 in the native byte order.
**
** Whether or not an error occurs when it is opened, resources
** associated with the [database connection] handle should be released by
** passing it to [sqlite3_close()] when it is no longer required.
**
** The sqlite3_open_v2() interface works like sqlite3_open()
** except that it accepts two additional parameters for additional control

** present, is ignored.
**
** ^SQLite uses the path component of the URI as the name of the disk file
** which contains the database. ^If the path begins with a '/' character, 
** then it is interpreted as an absolute path. ^If the path does not begin 
** with a '/' (meaning that the authority section is omitted from the URI)
** then the path is interpreted as a relative path. 
** ^(On windows, the first component of an absolute path 
** is a drive specification (e.g. "C:").)^
**
** [[core URI query parameters]]
** The query component of a URI may contain parameters that are interpreted
** either by SQLite itself, or by a [VFS | custom VFS implementation].
** SQLite and its built-in [VFSes] interpret the
** following query parameters:
**
** <ul>
**   <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of
**     a VFS object that provides the operating system interface that should
**     be used to access the database file on disk. ^If this option is set to
**     an empty string the default VFS object is used. ^Specifying an unknown
**     VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is

**
**   <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or
**     "private". ^Setting it to "shared" is equivalent to setting the
**     SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to
**     sqlite3_open_v2(). ^Setting the cache parameter to "private" is 
**     equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
**     ^If sqlite3_open_v2() is used and the "cache" parameter is present in
**     a URI filename, its value overrides any behavior requested by setting
**     SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
**
**  <li> <b>psow</b>: ^The psow parameter indicates whether or not the
**     [powersafe overwrite] property does or does not apply to the
**     storage media on which the database file resides.
**
**  <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter
**     which if set disables file locking in rollback journal modes.  This
**     is useful for accessing a database on a filesystem that does not
**     support locking.  Caution:  Database corruption might result if two
**     or more processes write to the same database and any one of those
**     processes uses nolock=1.
**
**  <li> <b>immutable</b>: ^The immutable parameter is a boolean query
**     parameter that indicates that the database file is stored on
**     read-only media.  ^When immutable is set, SQLite assumes that the
**     database file cannot be changed, even by a process with higher
**     privilege, and so the database is opened read-only and all locking
**     and change detection is disabled.  Caution: Setting the immutable
**     property on a database file that does in fact change can result
**     in incorrect query results and/or [SQLITE_CORRUPT] errors.
**     See also: [SQLITE_IOCAP_IMMUTABLE].
**       
** </ul>
**
** ^Specifying an unknown parameter in the query component of a URI is not an
** error.  Future versions of SQLite might understand additional query
** parameters.  See "[query parameters with special meaning to SQLite]" for
** additional information.
**

**          C:. Note that the %20 escaping in this example is not strictly 
**          necessary - space characters can be used literally
**          in URI filenames.
** <tr><td> file:data.db?mode=ro&cache=private <td> 
**          Open file "data.db" in the current directory for read-only access.
**          Regardless of whether or not shared-cache mode is enabled by
**          default, use a private cache.
** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td>
**          Open file "/home/fred/data.db". Use the special VFS "unix-dotfile"
**          that uses dot-files in place of posix advisory locking.
** <tr><td> file:data.db?mode=readonly <td> 
**          An error. "readonly" is not a valid option for the "mode" parameter.
** </table>
**
** ^URI hexadecimal escape sequences (%HH) are supported within the path and
** query components of a URI. A hexadecimal escape sequence consists of a
** percent sign - "%" - followed by exactly two hexadecimal digits 

SQLITE_API const char *sqlite3_uri_parameter(const char *zFilename, const char *zParam);
SQLITE_API int sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault);
SQLITE_API sqlite3_int64 sqlite3_uri_int64(const char*, const char*, sqlite3_int64);


/*
** CAPI3REF: Error Codes And Messages
** METHOD: sqlite3
**
** ^If the most recent sqlite3_* API call associated with 
** [database connection] D failed, then the sqlite3_errcode(D) interface
** returns the numeric [result code] or [extended result code] for that
** API call.
** If the most recent API call was successful,
** then the return value from sqlite3_errcode() is undefined.
** ^The sqlite3_extended_errcode()
** interface is the same except that it always returns the 
** [extended result code] even when extended result codes are
** disabled.
**
** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
** text that describes the error, as either UTF-8 or UTF-16 respectively.
** ^(Memory to hold the error message string is managed internally.

SQLITE_API int sqlite3_errcode(sqlite3 *db);
SQLITE_API int sqlite3_extended_errcode(sqlite3 *db);
SQLITE_API const char *sqlite3_errmsg(sqlite3*);
SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
SQLITE_API const char *sqlite3_errstr(int);

/*
** CAPI3REF: Prepared Statement Object
** KEYWORDS: {prepared statement} {prepared statements}
**
** An instance of this object represents a single SQL statement that
** has been compiled into binary form and is ready to be evaluated.
**
** Think of each SQL statement as a separate computer program.  The
** original SQL text is source code.  A prepared statement object 
** is the compiled object code.  All SQL must be converted into a
** prepared statement before it can be run.
**
** The life-cycle of a prepared statement object usually goes like this:
**
** <ol>
** <li> Create the prepared statement object using [sqlite3_prepare_v2()].

** <li> Bind values to [parameters] using the sqlite3_bind_*()
**      interfaces.
** <li> Run the SQL by calling [sqlite3_step()] one or more times.
** <li> Reset the prepared statement using [sqlite3_reset()] then go back
**      to step 2.  Do this zero or more times.
** <li> Destroy the object using [sqlite3_finalize()].
** </ol>



*/
typedef struct sqlite3_stmt sqlite3_stmt;

/*
** CAPI3REF: Run-time Limits
** METHOD: sqlite3
**
** ^(This interface allows the size of various constructs to be limited
** on a connection by connection basis.  The first parameter is the
** [database connection] whose limit is to be set or queried.  The
** second parameter is one of the [limit categories] that define a
** class of constructs to be size limited.  The third parameter is the
** new limit for that construct.)^

**
** [[SQLITE_LIMIT_VARIABLE_NUMBER]]
** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
** <dd>The maximum index number of any [parameter] in an SQL statement.)^
**
** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
** <dd>The maximum depth of recursion for triggers.</dd>)^
**
** [[SQLITE_LIMIT_WORKER_THREADS]] ^(<dt>SQLITE_LIMIT_WORKER_THREADS</dt>
** <dd>The maximum number of auxiliary worker threads that a single
** [prepared statement] may start.</dd>)^
** </dl>
*/
#define SQLITE_LIMIT_LENGTH                    0
#define SQLITE_LIMIT_SQL_LENGTH                1
#define SQLITE_LIMIT_COLUMN                    2
#define SQLITE_LIMIT_EXPR_DEPTH                3
#define SQLITE_LIMIT_COMPOUND_SELECT           4
#define SQLITE_LIMIT_VDBE_OP                   5
#define SQLITE_LIMIT_FUNCTION_ARG              6
#define SQLITE_LIMIT_ATTACHED                  7
#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH       8
#define SQLITE_LIMIT_VARIABLE_NUMBER           9
#define SQLITE_LIMIT_TRIGGER_DEPTH            10
#define SQLITE_LIMIT_WORKER_THREADS           11

/*
** CAPI3REF: Compiling An SQL Statement
** KEYWORDS: {SQL statement compiler}
** METHOD: sqlite3
** CONSTRUCTOR: sqlite3_stmt
**
** To execute an SQL query, it must first be compiled into a byte-code
** program using one of these routines.
**
** The first argument, "db", is a [database connection] obtained from a
** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
** [sqlite3_open16()].  The database connection must not have been closed.
**
** The second argument, "zSql", is the statement to be compiled, encoded
** as either UTF-8 or UTF-16.  The sqlite3_prepare() and sqlite3_prepare_v2()
** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()
** use UTF-16.
**
** ^If the nByte argument is negative, then zSql is read up to the
** first zero terminator. ^If nByte is positive, then it is the
** number of bytes read from zSql.  ^If nByte is zero, then no prepared
** statement is generated.

** If the caller knows that the supplied string is nul-terminated, then
** there is a small performance advantage to passing an nByte parameter that
** is the number of bytes in the input string <i>including</i>
** the nul-terminator.

**
** ^If pzTail is not NULL then *pzTail is made to point to the first byte
** past the end of the first SQL statement in zSql.  These routines only
** compile the first statement in zSql, so *pzTail is left pointing to
** what remains uncompiled.
**
** ^*ppStmt is left pointing to a compiled [prepared statement] that can be

** original SQL text. This causes the [sqlite3_step()] interface to
** behave differently in three ways:
**
** <ol>
** <li>
** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
** always used to do, [sqlite3_step()] will automatically recompile the SQL
** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY]
** retries will occur before sqlite3_step() gives up and returns an error.
** </li>
**
** <li>
** ^When an error occurs, [sqlite3_step()] will return one of the detailed
** [error codes] or [extended error codes].  ^The legacy behavior was that
** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
** and the application would have to make a second call to [sqlite3_reset()]

** then the statement will be automatically recompiled, as if there had been 
** a schema change, on the first  [sqlite3_step()] call following any change
** to the [sqlite3_bind_text | bindings] of that [parameter]. 
** ^The specific value of WHERE-clause [parameter] might influence the 
** choice of query plan if the parameter is the left-hand side of a [LIKE]
** or [GLOB] operator or if the parameter is compared to an indexed column
** and the [SQLITE_ENABLE_STAT3] compile-time option is enabled.

** </li>
** </ol>
*/
SQLITE_API int sqlite3_prepare(
  sqlite3 *db,            /* Database handle */
  const char *zSql,       /* SQL statement, UTF-8 encoded */
  int nByte,              /* Maximum length of zSql in bytes. */

  int nByte,              /* Maximum length of zSql in bytes. */
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
);

/*
** CAPI3REF: Retrieving Statement SQL
** METHOD: sqlite3_stmt
**
** ^The sqlite3_sql(P) interface returns a pointer to a copy of the UTF-8
** SQL text used to create [prepared statement] P if P was
** created by either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
** ^The sqlite3_expanded_sql(P) interface returns a pointer to a UTF-8
** string containing the SQL text of prepared statement P with
** [bound parameters] expanded.
**
** ^(For example, if a prepared statement is created using the SQL
** text "SELECT $abc,:xyz" and if parameter $abc is bound to integer 2345
** and parameter :xyz is unbound, then sqlite3_sql() will return
** the original string, "SELECT $abc,:xyz" but sqlite3_expanded_sql()
** will return "SELECT 2345,NULL".)^
**
** ^The sqlite3_expanded_sql() interface returns NULL if insufficient memory
** is available to hold the result, or if the result would exceed the
** the maximum string length determined by the [SQLITE_LIMIT_LENGTH].
**
** ^The [SQLITE_TRACE_SIZE_LIMIT] compile-time option limits the size of
** bound parameter expansions.  ^The [SQLITE_OMIT_TRACE] compile-time
** option causes sqlite3_expanded_sql() to always return NULL.
**
** ^The string returned by sqlite3_sql(P) is managed by SQLite and is
** automatically freed when the prepared statement is finalized.
** ^The string returned by sqlite3_expanded_sql(P), on the other hand,
** is obtained from [sqlite3_malloc()] and must be free by the application
** by passing it to [sqlite3_free()].
*/
SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);
SQLITE_API char *sqlite3_expanded_sql(sqlite3_stmt *pStmt);

/*
** CAPI3REF: Determine If An SQL Statement Writes The Database
** METHOD: sqlite3_stmt
**
** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if
** and only if the [prepared statement] X makes no direct changes to
** the content of the database file.
**
** Note that [application-defined SQL functions] or
** [virtual tables] might change the database indirectly as a side effect.  

** change the configuration of a database connection, they do not make 
** changes to the content of the database files on disk.
*/
SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt);

/*
** CAPI3REF: Determine If A Prepared Statement Has Been Reset
** METHOD: sqlite3_stmt
**
** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the
** [prepared statement] S has been stepped at least once using 
** [sqlite3_step(S)] but has neither run to completion (returned
** [SQLITE_DONE] from [sqlite3_step(S)]) nor
** been reset using [sqlite3_reset(S)].  ^The sqlite3_stmt_busy(S)
** interface returns false if S is a NULL pointer.  If S is not a 
** NULL pointer and is not a pointer to a valid [prepared statement]
** object, then the behavior is undefined and probably undesirable.
**
** This interface can be used in combination [sqlite3_next_stmt()]
** to locate all prepared statements associated with a database 

** for the values it stores.  ^Values stored in sqlite3_value objects
** can be integers, floating point values, strings, BLOBs, or NULL.
**
** An sqlite3_value object may be either "protected" or "unprotected".
** Some interfaces require a protected sqlite3_value.  Other interfaces
** will accept either a protected or an unprotected sqlite3_value.
** Every interface that accepts sqlite3_value arguments specifies
** whether or not it requires a protected sqlite3_value.  The
** [sqlite3_value_dup()] interface can be used to construct a new 
** protected sqlite3_value from an unprotected sqlite3_value.
**
** The terms "protected" and "unprotected" refer to whether or not
** a mutex is held.  An internal mutex is held for a protected
** sqlite3_value object but no mutex is held for an unprotected
** sqlite3_value object.  If SQLite is compiled to be single-threaded
** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
** or if SQLite is run in one of reduced mutex modes 

*/
typedef struct sqlite3_context sqlite3_context;

/*
** CAPI3REF: Binding Values To Prepared Statements
** KEYWORDS: {host parameter} {host parameters} {host parameter name}
** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
** METHOD: sqlite3_stmt
**
** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
** literals may be replaced by a [parameter] that matches one of following
** templates:
**
** <ul>
** <li>  ?

** ^The index for named parameters can be looked up using the
** [sqlite3_bind_parameter_index()] API if desired.  ^The index
** for "?NNN" parameters is the value of NNN.
** ^The NNN value must be between 1 and the [sqlite3_limit()]
** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
**
** ^The third argument is the value to bind to the parameter.
** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16()
** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter
** is ignored and the end result is the same as sqlite3_bind_null().
**
** ^(In those routines that have a fourth argument, its value is the
** number of bytes in the parameter.  To be clear: the value is the
** number of <u>bytes</u> in the value, not the number of characters.)^
** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16()
** is negative, then the length of the string is
** the number of bytes up to the first zero terminator.
** If the fourth parameter to sqlite3_bind_blob() is negative, then
** the behavior is undefined.
** If a non-negative fourth parameter is provided to sqlite3_bind_text()
** or sqlite3_bind_text16() or sqlite3_bind_text64() then
** that parameter must be the byte offset
** where the NUL terminator would occur assuming the string were NUL
** terminated.  If any NUL characters occur at byte offsets less than 
** the value of the fourth parameter then the resulting string value will
** contain embedded NULs.  The result of expressions involving strings
** with embedded NULs is undefined.
**
** ^The fifth argument to the BLOB and string binding interfaces
** is a destructor used to dispose of the BLOB or
** string after SQLite has finished with it.  ^The destructor is called
** to dispose of the BLOB or string even if the call to bind API fails.

** ^If the fifth argument is
** the special value [SQLITE_STATIC], then SQLite assumes that the
** information is in static, unmanaged space and does not need to be freed.
** ^If the fifth argument has the value [SQLITE_TRANSIENT], then
** SQLite makes its own private copy of the data immediately, before
** the sqlite3_bind_*() routine returns.
**
** ^The sixth argument to sqlite3_bind_text64() must be one of
** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]
** to specify the encoding of the text in the third parameter.  If
** the sixth argument to sqlite3_bind_text64() is not one of the
** allowed values shown above, or if the text encoding is different
** from the encoding specified by the sixth parameter, then the behavior
** is undefined.
**
** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
** is filled with zeroes.  ^A zeroblob uses a fixed amount of memory
** (just an integer to hold its size) while it is being processed.
** Zeroblobs are intended to serve as placeholders for BLOBs whose
** content is later written using
** [sqlite3_blob_open | incremental BLOB I/O] routines.

** result is undefined and probably harmful.
**
** ^Bindings are not cleared by the [sqlite3_reset()] routine.
** ^Unbound parameters are interpreted as NULL.
**
** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
** [error code] if anything goes wrong.
** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB
** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or
** [SQLITE_MAX_LENGTH].
** ^[SQLITE_RANGE] is returned if the parameter
** index is out of range.  ^[SQLITE_NOMEM] is returned if malloc() fails.
**
** See also: [sqlite3_bind_parameter_count()],
** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
*/
SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
SQLITE_API int sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64,
                        void(*)(void*));
SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double);
SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int);
SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int);
SQLITE_API int sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*));
SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
SQLITE_API int sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64,
                         void(*)(void*), unsigned char encoding);
SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
SQLITE_API int sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64);

/*
** CAPI3REF: Number Of SQL Parameters
** METHOD: sqlite3_stmt
**
** ^This routine can be used to find the number of [SQL parameters]
** in a [prepared statement].  SQL parameters are tokens of the
** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
** placeholders for values that are [sqlite3_bind_blob | bound]
** to the parameters at a later time.
**
** ^(This routine actually returns the index of the largest (rightmost)
** parameter. For all forms except ?NNN, this will correspond to the
** number of unique parameters.  If parameters of the ?NNN form are used,
** there may be gaps in the list.)^
**
** See also: [sqlite3_bind_blob|sqlite3_bind()],
** [sqlite3_bind_parameter_name()], and
** [sqlite3_bind_parameter_index()].
*/
SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);

/*
** CAPI3REF: Name Of A Host Parameter
** METHOD: sqlite3_stmt
**
** ^The sqlite3_bind_parameter_name(P,N) interface returns
** the name of the N-th [SQL parameter] in the [prepared statement] P.
** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
** respectively.
** In other words, the initial ":" or "$" or "@" or "?"

** [sqlite3_bind_parameter_count()], and
** [sqlite3_bind_parameter_index()].
*/
SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);

/*
** CAPI3REF: Index Of A Parameter With A Given Name
** METHOD: sqlite3_stmt
**
** ^Return the index of an SQL parameter given its name.  ^The
** index value returned is suitable for use as the second
** parameter to [sqlite3_bind_blob|sqlite3_bind()].  ^A zero
** is returned if no matching parameter is found.  ^The parameter
** name must be given in UTF-8 even if the original statement
** was prepared from UTF-16 text using [sqlite3_prepare16_v2()].
**
** See also: [sqlite3_bind_blob|sqlite3_bind()],
** [sqlite3_bind_parameter_count()], and
** [sqlite3_bind_parameter_name()].
*/
SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);

/*
** CAPI3REF: Reset All Bindings On A Prepared Statement
** METHOD: sqlite3_stmt
**
** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
** the [sqlite3_bind_blob | bindings] on a [prepared statement].
** ^Use this routine to reset all host parameters to NULL.
*/
SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*);

/*
** CAPI3REF: Number Of Columns In A Result Set
** METHOD: sqlite3_stmt
**
** ^Return the number of columns in the result set returned by the
** [prepared statement]. ^This routine returns 0 if pStmt is an SQL
** statement that does not return data (for example an [UPDATE]).
**
** See also: [sqlite3_data_count()]
*/
SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);

/*
** CAPI3REF: Column Names In A Result Set
** METHOD: sqlite3_stmt
**
** ^These routines return the name assigned to a particular column
** in the result set of a [SELECT] statement.  ^The sqlite3_column_name()
** interface returns a pointer to a zero-terminated UTF-8 string
** and sqlite3_column_name16() returns a pointer to a zero-terminated
** UTF-16 string.  ^The first parameter is the [prepared statement]
** that implements the [SELECT] statement. ^The second parameter is the

** one release of SQLite to the next.
*/
SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N);
SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N);

/*
** CAPI3REF: Source Of Data In A Query Result
** METHOD: sqlite3_stmt
**
** ^These routines provide a means to determine the database, table, and
** table column that is the origin of a particular result column in
** [SELECT] statement.
** ^The name of the database or table or column can be returned as
** either a UTF-8 or UTF-16 string.  ^The _database_ routines return
** the database name, the _table_ routines return the table name, and

SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int);
SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);

/*
** CAPI3REF: Declared Datatype Of A Query Result
** METHOD: sqlite3_stmt
**
** ^(The first parameter is a [prepared statement].
** If this statement is a [SELECT] statement and the Nth column of the
** returned result set of that [SELECT] is a table column (not an
** expression or subquery) then the declared type of the table
** column is returned.)^  ^If the Nth column of the result set is an
** expression or subquery, then a NULL pointer is returned.

** used to hold those values.
*/
SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int);
SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);

/*
** CAPI3REF: Evaluate An SQL Statement
** METHOD: sqlite3_stmt
**
** After a [prepared statement] has been prepared using either
** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy
** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
** must be called one or more times to evaluate the statement.
**
** The details of the behavior of the sqlite3_step() interface depend

** more threads at the same moment in time.
**
** For all versions of SQLite up to and including 3.6.23.1, a call to
** [sqlite3_reset()] was required after sqlite3_step() returned anything
** other than [SQLITE_ROW] before any subsequent invocation of
** sqlite3_step().  Failure to reset the prepared statement using 
** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from
** sqlite3_step().  But after [version 3.6.23.1] ([dateof:3.6.23.1],
** sqlite3_step() began
** calling [sqlite3_reset()] automatically in this circumstance rather
** than returning [SQLITE_MISUSE].  This is not considered a compatibility
** break because any application that ever receives an SQLITE_MISUSE error
** is broken by definition.  The [SQLITE_OMIT_AUTORESET] compile-time option
** can be used to restore the legacy behavior.
**
** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()

** then the more specific [error codes] are returned directly
** by sqlite3_step().  The use of the "v2" interface is recommended.
*/
SQLITE_API int sqlite3_step(sqlite3_stmt*);

/*
** CAPI3REF: Number of columns in a result set
** METHOD: sqlite3_stmt
**
** ^The sqlite3_data_count(P) interface returns the number of columns in the
** current row of the result set of [prepared statement] P.
** ^If prepared statement P does not have results ready to return
** (via calls to the [sqlite3_column_int | sqlite3_column_*()] of
** interfaces) then sqlite3_data_count(P) returns 0.
** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.

# define SQLITE_TEXT     3
#endif
#define SQLITE3_TEXT     3

/*
** CAPI3REF: Result Values From A Query
** KEYWORDS: {column access functions}
** METHOD: sqlite3_stmt

**
** ^These routines return information about a single column of the current
** result row of a query.  ^In every case the first argument is a pointer
** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
** that was returned from [sqlite3_prepare_v2()] or one of its variants)
** and the second argument is the index of the column for which information
** should be returned. ^The leftmost column of the result set has the index 0.

** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
** bytes in the string, not the number of characters.
**
** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
** even empty strings, are always zero-terminated.  ^The return
** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
**
** <b>Warning:</b> ^The object returned by [sqlite3_column_value()] is an
** [unprotected sqlite3_value] object.  In a multithreaded environment,
** an unprotected sqlite3_value object may only be used safely with
** [sqlite3_bind_value()] and [sqlite3_result_value()].
** If the [unprotected sqlite3_value] object returned by
** [sqlite3_column_value()] is used in any other way, including calls
** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
** or [sqlite3_value_bytes()], the behavior is not threadsafe.
**
** These routines attempt to convert the value where appropriate.  ^For
** example, if the internal representation is FLOAT and a text result
** is requested, [sqlite3_snprintf()] is used internally to perform the
** conversion automatically.  ^(The following table details the conversions
** that are applied:
**
** <blockquote>
** <table border="1">
** <tr><th> Internal<br>Type <th> Requested<br>Type <th>  Conversion
**
** <tr><td>  NULL    <td> INTEGER   <td> Result is 0
** <tr><td>  NULL    <td>  FLOAT    <td> Result is 0.0
** <tr><td>  NULL    <td>   TEXT    <td> Result is a NULL pointer
** <tr><td>  NULL    <td>   BLOB    <td> Result is a NULL pointer
** <tr><td> INTEGER  <td>  FLOAT    <td> Convert from integer to float
** <tr><td> INTEGER  <td>   TEXT    <td> ASCII rendering of the integer
** <tr><td> INTEGER  <td>   BLOB    <td> Same as INTEGER->TEXT
** <tr><td>  FLOAT   <td> INTEGER   <td> [CAST] to INTEGER
** <tr><td>  FLOAT   <td>   TEXT    <td> ASCII rendering of the float
** <tr><td>  FLOAT   <td>   BLOB    <td> [CAST] to BLOB
** <tr><td>  TEXT    <td> INTEGER   <td> [CAST] to INTEGER
** <tr><td>  TEXT    <td>  FLOAT    <td> [CAST] to REAL
** <tr><td>  TEXT    <td>   BLOB    <td> No change
** <tr><td>  BLOB    <td> INTEGER   <td> [CAST] to INTEGER
** <tr><td>  BLOB    <td>  FLOAT    <td> [CAST] to REAL
** <tr><td>  BLOB    <td>   TEXT    <td> Add a zero terminator if needed
** </table>
** </blockquote>)^
**






** Note that when type conversions occur, pointers returned by prior
** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
** sqlite3_column_text16() may be invalidated.
** Type conversions and pointer invalidations might occur
** in the following cases:
**
** <ul>

**
** ^Conversions between UTF-16be and UTF-16le are always done in place and do
** not invalidate a prior pointer, though of course the content of the buffer
** that the prior pointer references will have been modified.  Other kinds
** of conversion are done in place when it is possible, but sometimes they
** are not possible and in those cases prior pointers are invalidated.
**
** The safest policy is to invoke these routines
** in one of the following ways:
**
** <ul>
**  <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
**  <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
**  <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
** </ul>
**
** In other words, you should call sqlite3_column_text(),
** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
** into the desired format, then invoke sqlite3_column_bytes() or
** sqlite3_column_bytes16() to find the size of the result.  Do not mix calls
** to sqlite3_column_text() or sqlite3_column_blob() with calls to
** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
** with calls to sqlite3_column_bytes().
**
** ^The pointers returned are valid until a type conversion occurs as
** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
** [sqlite3_finalize()] is called.  ^The memory space used to hold strings
** and BLOBs is freed automatically.  Do <em>not</em> pass the pointers returned
** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
** [sqlite3_free()].
**
** ^(If a memory allocation error occurs during the evaluation of any
** of these routines, a default value is returned.  The default value
** is either the integer 0, the floating point number 0.0, or a NULL
** pointer.  Subsequent calls to [sqlite3_errcode()] will return
** [SQLITE_NOMEM].)^

SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol);
SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);

/*
** CAPI3REF: Destroy A Prepared Statement Object
** DESTRUCTOR: sqlite3_stmt
**
** ^The sqlite3_finalize() function is called to delete a [prepared statement].
** ^If the most recent evaluation of the statement encountered no errors
** or if the statement is never been evaluated, then sqlite3_finalize() returns
** SQLITE_OK.  ^If the most recent evaluation of statement S failed, then
** sqlite3_finalize(S) returns the appropriate [error code] or
** [extended error code].

** statement after it has been finalized can result in undefined and
** undesirable behavior such as segfaults and heap corruption.
*/
SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt);

/*
** CAPI3REF: Reset A Prepared Statement Object
** METHOD: sqlite3_stmt
**
** The sqlite3_reset() function is called to reset a [prepared statement]
** object back to its initial state, ready to be re-executed.
** ^Any SQL statement variables that had values bound to them using
** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
** Use [sqlite3_clear_bindings()] to reset the bindings.
**

SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);

/*
** CAPI3REF: Create Or Redefine SQL Functions
** KEYWORDS: {function creation routines}
** KEYWORDS: {application-defined SQL function}
** KEYWORDS: {application-defined SQL functions}
** METHOD: sqlite3
**
** ^These functions (collectively known as "function creation routines")
** are used to add SQL functions or aggregates or to redefine the behavior
** of existing SQL functions or aggregates.  The only differences between
** these routines are the text encoding expected for
** the second parameter (the name of the function being created)
** and the presence or absence of a destructor callback for

** aggregate may take any number of arguments between 0 and the limit
** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]).  If the third
** parameter is less than -1 or greater than 127 then the behavior is
** undefined.
**
** ^The fourth parameter, eTextRep, specifies what
** [SQLITE_UTF8 | text encoding] this SQL function prefers for
** its parameters.  The application should set this parameter to
** [SQLITE_UTF16LE] if the function implementation invokes 
** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the
** implementation invokes [sqlite3_value_text16be()] on an input, or

** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8]
** otherwise.  ^The same SQL function may be registered multiple times using
** different preferred text encodings, with different implementations for
** each encoding.
** ^When multiple implementations of the same function are available, SQLite
** will pick the one that involves the least amount of data conversion.

**
** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC]
** to signal that the function will always return the same result given
** the same inputs within a single SQL statement.  Most SQL functions are
** deterministic.  The built-in [random()] SQL function is an example of a
** function that is not deterministic.  The SQLite query planner is able to
** perform additional optimizations on deterministic functions, so use
** of the [SQLITE_DETERMINISTIC] flag is recommended where possible.
**
** ^(The fifth parameter is an arbitrary pointer.  The implementation of the
** function can gain access to this pointer using [sqlite3_user_data()].)^
**
** ^The sixth, seventh and eighth parameters, xFunc, xStep and xFinal, are
** pointers to C-language functions that implement the SQL function or
** aggregate. ^A scalar SQL function requires an implementation of the xFunc

/*
** CAPI3REF: Text Encodings
**
** These constant define integer codes that represent the various
** text encodings supported by SQLite.
*/
#define SQLITE_UTF8           1    /* IMP: R-37514-35566 */
#define SQLITE_UTF16LE        2    /* IMP: R-03371-37637 */
#define SQLITE_UTF16BE        3    /* IMP: R-51971-34154 */
#define SQLITE_UTF16          4    /* Use native byte order */
#define SQLITE_ANY            5    /* Deprecated */
#define SQLITE_UTF16_ALIGNED  8    /* sqlite3_create_collation only */

/*
** CAPI3REF: Function Flags
**
** These constants may be ORed together with the 
** [SQLITE_UTF8 | preferred text encoding] as the fourth argument
** to [sqlite3_create_function()], [sqlite3_create_function16()], or
** [sqlite3_create_function_v2()].
*/
#define SQLITE_DETERMINISTIC    0x800

/*
** CAPI3REF: Deprecated Functions
** DEPRECATED
**
** These functions are [deprecated].  In order to maintain
** backwards compatibility with older code, these functions continue 
** to be supported.  However, new applications should avoid
** the use of these functions.  To encourage programmers to avoid
** these functions, we will not explain what they do.
*/
#ifndef SQLITE_OMIT_DEPRECATED
SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),
                      void*,sqlite3_int64);
#endif

/*
** CAPI3REF: Obtaining SQL Values
** METHOD: sqlite3_value
**
** The C-language implementation of SQL functions and aggregates uses
** this set of interface routines to access the parameter values on
** the function or aggregate.  
**
** The xFunc (for scalar functions) or xStep (for aggregates) parameters
** to [sqlite3_create_function()] and [sqlite3_create_function16()]
** define callbacks that implement the SQL functions and aggregates.
** The 3rd parameter to these callbacks is an array of pointers to
** [protected sqlite3_value] objects.  There is one [sqlite3_value] object for
** each parameter to the SQL function.  These routines are used to
** extract values from the [sqlite3_value] objects.
**
** These routines work only with [protected sqlite3_value] objects.
** Any attempt to use these routines on an [unprotected sqlite3_value]
** object results in undefined behavior.
**
** ^These routines work just like the corresponding [column access functions]
** except that these routines take a single [protected sqlite3_value] object
** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
**
** ^The sqlite3_value_text16() interface extracts a UTF-16 string
** in the native byte-order of the host machine.  ^The
** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
** extract UTF-16 strings as big-endian and little-endian respectively.
**

SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*);
SQLITE_API const void *sqlite3_value_text16(sqlite3_value*);
SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*);
SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*);
SQLITE_API int sqlite3_value_type(sqlite3_value*);
SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);

/*
** CAPI3REF: Finding The Subtype Of SQL Values
** METHOD: sqlite3_value
**
** The sqlite3_value_subtype(V) function returns the subtype for
** an [application-defined SQL function] argument V.  The subtype
** information can be used to pass a limited amount of context from
** one SQL function to another.  Use the [sqlite3_result_subtype()]
** routine to set the subtype for the return value of an SQL function.
**
** SQLite makes no use of subtype itself.  It merely passes the subtype
** from the result of one [application-defined SQL function] into the
** input of another.
*/
SQLITE_API unsigned int sqlite3_value_subtype(sqlite3_value*);

/*
** CAPI3REF: Copy And Free SQL Values
** METHOD: sqlite3_value
**
** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value]
** object D and returns a pointer to that copy.  ^The [sqlite3_value] returned
** is a [protected sqlite3_value] object even if the input is not.
** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a
** memory allocation fails.
**
** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object
** previously obtained from [sqlite3_value_dup()].  ^If V is a NULL pointer
** then sqlite3_value_free(V) is a harmless no-op.
*/
SQLITE_API sqlite3_value *sqlite3_value_dup(const sqlite3_value*);
SQLITE_API void sqlite3_value_free(sqlite3_value*);

/*
** CAPI3REF: Obtain Aggregate Function Context
** METHOD: sqlite3_context
**
** Implementations of aggregate SQL functions use this
** routine to allocate memory for storing their state.
**
** ^The first time the sqlite3_aggregate_context(C,N) routine is called 
** for a particular aggregate function, SQLite
** allocates N of memory, zeroes out that memory, and returns a pointer
** to the new memory. ^On second and subsequent calls to
** sqlite3_aggregate_context() for the same aggregate function instance,
** the same buffer is returned.  Sqlite3_aggregate_context() is normally
** called once for each invocation of the xStep callback and then one
** last time when the xFinal callback is invoked.  ^(When no rows match
** an aggregate query, the xStep() callback of the aggregate function
** implementation is never called and xFinal() is called exactly once.
** In those cases, sqlite3_aggregate_context() might be called for the
** first time from within xFinal().)^
**
** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer 
** when first called if N is less than or equal to zero or if a memory
** allocate error occurs.
**
** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
** determined by the N parameter on first successful call.  Changing the
** value of N in subsequent call to sqlite3_aggregate_context() within
** the same aggregate function instance will not resize the memory
** allocation.)^  Within the xFinal callback, it is customary to set
** N=0 in calls to sqlite3_aggregate_context(C,N) so that no 
** pointless memory allocations occur.
**
** ^SQLite automatically frees the memory allocated by 
** sqlite3_aggregate_context() when the aggregate query concludes.
**
** The first parameter must be a copy of the
** [sqlite3_context | SQL function context] that is the first parameter
** to the xStep or xFinal callback routine that implements the aggregate
** function.
**
** This routine must be called from the same thread in which
** the aggregate SQL function is running.
*/
SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);

/*
** CAPI3REF: User Data For Functions
** METHOD: sqlite3_context
**
** ^The sqlite3_user_data() interface returns a copy of
** the pointer that was the pUserData parameter (the 5th parameter)
** of the [sqlite3_create_function()]
** and [sqlite3_create_function16()] routines that originally
** registered the application defined function.
**
** This routine must be called from the same thread in which
** the application-defined function is running.
*/
SQLITE_API void *sqlite3_user_data(sqlite3_context*);

/*
** CAPI3REF: Database Connection For Functions
** METHOD: sqlite3_context
**
** ^The sqlite3_context_db_handle() interface returns a copy of
** the pointer to the [database connection] (the 1st parameter)
** of the [sqlite3_create_function()]
** and [sqlite3_create_function16()] routines that originally
** registered the application defined function.
*/
SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*);

/*
** CAPI3REF: Function Auxiliary Data
** METHOD: sqlite3_context
**
** These functions may be used by (non-aggregate) SQL functions to
** associate metadata with argument values. If the same value is passed to
** multiple invocations of the same SQL function during query execution, under
** some circumstances the associated metadata may be preserved.  An example
** of where this might be useful is in a regular-expression matching
** function. The compiled version of the regular expression can be stored as
** metadata associated with the pattern string.  
** Then as long as the pattern string remains the same,
** the compiled regular expression can be reused on multiple
** invocations of the same function.

**
** ^The sqlite3_get_auxdata() interface returns a pointer to the metadata
** associated by the sqlite3_set_auxdata() function with the Nth argument
** value to the application-defined function. ^If there is no metadata

** associated with the function argument, this sqlite3_get_auxdata() interface
** returns a NULL pointer.
**
** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th

** argument of the application-defined function.  ^Subsequent
** calls to sqlite3_get_auxdata(C,N) return P from the most recent
** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or
** NULL if the metadata has been discarded.
** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL,
** SQLite will invoke the destructor function X with parameter P exactly
** once, when the metadata is discarded.
** SQLite is free to discard the metadata at any time, including: <ul>
** <li> ^(when the corresponding function parameter changes)^, or
** <li> ^(when [sqlite3_reset()] or [sqlite3_finalize()] is called for the
**      SQL statement)^, or
** <li> ^(when sqlite3_set_auxdata() is invoked again on the same
**       parameter)^, or
** <li> ^(during the original sqlite3_set_auxdata() call when a memory 
**      allocation error occurs.)^ </ul>
**
** Note the last bullet in particular.  The destructor X in 
** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the
** sqlite3_set_auxdata() interface even returns.  Hence sqlite3_set_auxdata()
** should be called near the end of the function implementation and the
** function implementation should not make any use of P after
** sqlite3_set_auxdata() has been called.
**
** ^(In practice, metadata is preserved between function calls for
** function parameters that are compile-time constants, including literal
** values and [parameters] and expressions composed from the same.)^
**
** These routines must be called from the same thread in which
** the SQL function is running.
*/
SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N);
SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));


/*
** CAPI3REF: Constants Defining Special Destructor Behavior
**
** These are special values for the destructor that is passed in as the
** final argument to routines like [sqlite3_result_blob()].  ^If the destructor
** argument is SQLITE_STATIC, it means that the content pointer is constant
** and will never change.  It does not need to be destroyed.  ^The
** SQLITE_TRANSIENT value means that the content will likely change in
** the near future and that SQLite should make its own private copy of
** the content before returning.
**
** The typedef is necessary to work around problems in certain
** C++ compilers.
*/
typedef void (*sqlite3_destructor_type)(void*);
#define SQLITE_STATIC      ((sqlite3_destructor_type)0)
#define SQLITE_TRANSIENT   ((sqlite3_destructor_type)-1)

/*
** CAPI3REF: Setting The Result Of An SQL Function
** METHOD: sqlite3_context
**
** These routines are used by the xFunc or xFinal callbacks that
** implement SQL functions and aggregates.  See
** [sqlite3_create_function()] and [sqlite3_create_function16()]
** for additional information.
**
** These functions work very much like the [parameter binding] family of
** functions used to bind values to host parameters in prepared statements.
** Refer to the [SQL parameter] documentation for additional information.
**
** ^The sqlite3_result_blob() interface sets the result from
** an application-defined function to be the BLOB whose content is pointed
** to by the second parameter and which is N bytes long where N is the
** third parameter.
**
** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N)
** interfaces set the result of the application-defined function to be
** a BLOB containing all zero bytes and N bytes in size.
**
** ^The sqlite3_result_double() interface sets the result from
** an application-defined function to be a floating point value specified
** by its 2nd argument.
**
** ^The sqlite3_result_error() and sqlite3_result_error16() functions
** cause the implemented SQL function to throw an exception.

** of the application-defined function to be NULL.
**
** ^The sqlite3_result_text(), sqlite3_result_text16(),
** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
** set the return value of the application-defined function to be
** a text string which is represented as UTF-8, UTF-16 native byte order,
** UTF-16 little endian, or UTF-16 big endian, respectively.
** ^The sqlite3_result_text64() interface sets the return value of an
** application-defined function to be a text string in an encoding
** specified by the fifth (and last) parameter, which must be one
** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE].
** ^SQLite takes the text result from the application from
** the 2nd parameter of the sqlite3_result_text* interfaces.
** ^If the 3rd parameter to the sqlite3_result_text* interfaces
** is negative, then SQLite takes result text from the 2nd parameter
** through the first zero character.
** ^If the 3rd parameter to the sqlite3_result_text* interfaces
** is non-negative, then as many bytes (not characters) of the text

** when it has finished using that result.
** ^If the 4th parameter to the sqlite3_result_text* interfaces
** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
** then SQLite makes a copy of the result into space obtained from
** from [sqlite3_malloc()] before it returns.
**
** ^The sqlite3_result_value() interface sets the result of
** the application-defined function to be a copy of the
** [unprotected sqlite3_value] object specified by the 2nd parameter.  ^The
** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
** so that the [sqlite3_value] specified in the parameter may change or
** be deallocated after sqlite3_result_value() returns without harm.
** ^A [protected sqlite3_value] object may always be used where an
** [unprotected sqlite3_value] object is required, so either
** kind of [sqlite3_value] object can be used with this interface.
**
** If these routines are called from within the different thread
** than the one containing the application-defined function that received
** the [sqlite3_context] pointer, the results are undefined.
*/
SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
SQLITE_API void sqlite3_result_blob64(sqlite3_context*,const void*,
                           sqlite3_uint64,void(*)(void*));
SQLITE_API void sqlite3_result_double(sqlite3_context*, double);
SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int);
SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int);
SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*);
SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*);
SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int);
SQLITE_API void sqlite3_result_int(sqlite3_context*, int);
SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
SQLITE_API void sqlite3_result_null(sqlite3_context*);
SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
SQLITE_API void sqlite3_result_text64(sqlite3_context*, const char*,sqlite3_uint64,
                           void(*)(void*), unsigned char encoding);
SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n);
SQLITE_API int sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n);


/*
** CAPI3REF: Setting The Subtype Of An SQL Function
** METHOD: sqlite3_context
**
** The sqlite3_result_subtype(C,T) function causes the subtype of
** the result from the [application-defined SQL function] with 
** [sqlite3_context] C to be the value T.  Only the lower 8 bits 
** of the subtype T are preserved in current versions of SQLite;
** higher order bits are discarded.
** The number of subtype bytes preserved by SQLite might increase
** in future releases of SQLite.
*/
SQLITE_API void sqlite3_result_subtype(sqlite3_context*,unsigned int);

/*
** CAPI3REF: Define New Collating Sequences
** METHOD: sqlite3
**
** ^These functions add, remove, or modify a [collation] associated
** with the [database connection] specified as the first argument.
**
** ^The name of the collation is a UTF-8 string
** for sqlite3_create_collation() and sqlite3_create_collation_v2()
** and a UTF-16 string in native byte order for sqlite3_create_collation16().

  int eTextRep, 
  void *pArg,
  int(*xCompare)(void*,int,const void*,int,const void*)
);

/*
** CAPI3REF: Collation Needed Callbacks
** METHOD: sqlite3
**
** ^To avoid having to register all collation sequences before a database
** can be used, a single callback function may be registered with the
** [database connection] to be invoked whenever an undefined collation
** sequence is required.
**
** ^If the function is registered using the sqlite3_collation_needed() API,

** The code to implement this API is not available in the public release
** of SQLite.
*/
SQLITE_API int sqlite3_key(
  sqlite3 *db,                   /* Database to be rekeyed */
  const void *pKey, int nKey     /* The key */
);
SQLITE_API int sqlite3_key_v2(
  sqlite3 *db,                   /* Database to be rekeyed */
  const char *zDbName,           /* Name of the database */
  const void *pKey, int nKey     /* The key */
);

/*
** Change the key on an open database.  If the current database is not
** encrypted, this routine will encrypt it.  If pNew==0 or nNew==0, the
** database is decrypted.
**
** The code to implement this API is not available in the public release
** of SQLite.
*/
SQLITE_API int sqlite3_rekey(
  sqlite3 *db,                   /* Database to be rekeyed */
  const void *pKey, int nKey     /* The new key */
);
SQLITE_API int sqlite3_rekey_v2(
  sqlite3 *db,                   /* Database to be rekeyed */
  const char *zDbName,           /* Name of the database */
  const void *pKey, int nKey     /* The new key */
);

/*
** Specify the activation key for a SEE database.  Unless 
** activated, none of the SEE routines will work.
*/
SQLITE_API void sqlite3_activate_see(
  const char *zPassPhrase        /* Activation phrase */

**
** ^(If this global variable is made to point to a string which is
** the name of a folder (a.k.a. directory), then all temporary files
** created by SQLite when using a built-in [sqlite3_vfs | VFS]
** will be placed in that directory.)^  ^If this variable
** is a NULL pointer, then SQLite performs a search for an appropriate
** temporary file directory.
**
** Applications are strongly discouraged from using this global variable.
** It is required to set a temporary folder on Windows Runtime (WinRT).
** But for all other platforms, it is highly recommended that applications
** neither read nor write this variable.  This global variable is a relic
** that exists for backwards compatibility of legacy applications and should
** be avoided in new projects.
**
** It is not safe to read or modify this variable in more than one
** thread at a time.  It is not safe to read or modify this variable
** if a [database connection] is being used at the same time in a separate
** thread.
** It is intended that this variable be set once
** as part of process initialization and before any SQLite interface
** routines have been called and that this variable remain unchanged
** thereafter.
**
** ^The [temp_store_directory pragma] may modify this variable and cause
** it to point to memory obtained from [sqlite3_malloc].  ^Furthermore,
** the [temp_store_directory pragma] always assumes that any string
** that this variable points to is held in memory obtained from 
** [sqlite3_malloc] and the pragma may attempt to free that memory
** using [sqlite3_free].
** Hence, if this variable is modified directly, either it should be
** made NULL or made to point to memory obtained from [sqlite3_malloc]
** or else the use of the [temp_store_directory pragma] should be avoided.
** Except when requested by the [temp_store_directory pragma], SQLite
** does not free the memory that sqlite3_temp_directory points to.  If
** the application wants that memory to be freed, it must do
** so itself, taking care to only do so after all [database connection]
** objects have been destroyed.
**
** <b>Note to Windows Runtime users:</b>  The temporary directory must be set
** prior to calling [sqlite3_open] or [sqlite3_open_v2].  Otherwise, various
** features that require the use of temporary files may fail.  Here is an
** example of how to do this using C++ with the Windows Runtime:
**
** <blockquote><pre>

** or else the use of the [data_store_directory pragma] should be avoided.
*/
SQLITE_API SQLITE_EXTERN char *sqlite3_data_directory;

/*
** CAPI3REF: Test For Auto-Commit Mode
** KEYWORDS: {autocommit mode}
** METHOD: sqlite3
**
** ^The sqlite3_get_autocommit() interface returns non-zero or
** zero if the given database connection is or is not in autocommit mode,
** respectively.  ^Autocommit mode is on by default.
** ^Autocommit mode is disabled by a [BEGIN] statement.
** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
**

** connection while this routine is running, then the return value
** is undefined.
*/
SQLITE_API int sqlite3_get_autocommit(sqlite3*);

/*
** CAPI3REF: Find The Database Handle Of A Prepared Statement
** METHOD: sqlite3_stmt
**
** ^The sqlite3_db_handle interface returns the [database connection] handle
** to which a [prepared statement] belongs.  ^The [database connection]
** returned by sqlite3_db_handle is the same [database connection]
** that was the first argument
** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
** create the statement in the first place.
*/
SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*);

/*
** CAPI3REF: Return The Filename For A Database Connection
** METHOD: sqlite3
**
** ^The sqlite3_db_filename(D,N) interface returns a pointer to a filename
** associated with database N of connection D.  ^The main database file
** has the name "main".  If there is no attached database N on the database
** connection D, or if database N is a temporary or in-memory database, then
** a NULL pointer is returned.
**
** ^The filename returned by this function is the output of the
** xFullPathname method of the [VFS].  ^In other words, the filename
** will be an absolute pathname, even if the filename used
** to open the database originally was a URI or relative pathname.
*/
SQLITE_API const char *sqlite3_db_filename(sqlite3 *db, const char *zDbName);

/*
** CAPI3REF: Determine if a database is read-only
** METHOD: sqlite3
**
** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N
** of connection D is read-only, 0 if it is read/write, or -1 if N is not
** the name of a database on connection D.
*/
SQLITE_API int sqlite3_db_readonly(sqlite3 *db, const char *zDbName);

/*
** CAPI3REF: Find the next prepared statement
** METHOD: sqlite3
**
** ^This interface returns a pointer to the next [prepared statement] after
** pStmt associated with the [database connection] pDb.  ^If pStmt is NULL
** then this interface returns a pointer to the first prepared statement
** associated with the database connection pDb.  ^If no prepared statement
** satisfies the conditions of this routine, it returns NULL.
**
** The [database connection] pointer D in a call to
** [sqlite3_next_stmt(D,S)] must refer to an open database
** connection and in particular must not be a NULL pointer.
*/
SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);

/*
** CAPI3REF: Commit And Rollback Notification Callbacks
** METHOD: sqlite3
**
** ^The sqlite3_commit_hook() interface registers a callback
** function to be invoked whenever a transaction is [COMMIT | committed].
** ^Any callback set by a previous call to sqlite3_commit_hook()
** for the same database connection is overridden.
** ^The sqlite3_rollback_hook() interface registers a callback
** function to be invoked whenever a transaction is [ROLLBACK | rolled back].

** See also the [sqlite3_update_hook()] interface.
*/
SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);

/*
** CAPI3REF: Data Change Notification Callbacks
** METHOD: sqlite3
**
** ^The sqlite3_update_hook() interface registers a callback function
** with the [database connection] identified by the first argument
** to be invoked whenever a row is updated, inserted or deleted in
** a [rowid table].
** ^Any callback set by a previous call to this function
** for the same database connection is overridden.
**
** ^The second argument is a pointer to the function to invoke when a
** row is updated, inserted or deleted in a rowid table.
** ^The first argument to the callback is a copy of the third argument
** to sqlite3_update_hook().
** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
** or [SQLITE_UPDATE], depending on the operation that caused the callback
** to be invoked.
** ^The third and fourth arguments to the callback contain pointers to the
** database and table name containing the affected row.
** ^The final callback parameter is the [rowid] of the row.
** ^In the case of an update, this is the [rowid] after the update takes place.
**
** ^(The update hook is not invoked when internal system tables are
** modified (i.e. sqlite_master and sqlite_sequence).)^
** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified.
**
** ^In the current implementation, the update hook
** is not invoked when duplication rows are deleted because of an
** [ON CONFLICT | ON CONFLICT REPLACE] clause.  ^Nor is the update hook
** invoked when rows are deleted using the [truncate optimization].
** The exceptions defined in this paragraph might change in a future
** release of SQLite.
**
** The update hook implementation must not do anything that will modify
** the database connection that invoked the update hook.  Any actions
** to modify the database connection must be deferred until after the
** completion of the [sqlite3_step()] call that triggered the update hook.
** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
** database connections for the meaning of "modify" in this paragraph.
**
** ^The sqlite3_update_hook(D,C,P) function
** returns the P argument from the previous call
** on the same [database connection] D, or NULL for
** the first call on D.
**
** See also the [sqlite3_commit_hook()], [sqlite3_rollback_hook()],
** and [sqlite3_preupdate_hook()] interfaces.
*/
SQLITE_API void *sqlite3_update_hook(
  sqlite3*, 
  void(*)(void *,int ,char const *,char const *,sqlite3_int64),
  void*
);

/*
** CAPI3REF: Enable Or Disable Shared Pager Cache
**
** ^(This routine enables or disables the sharing of the database cache
** and schema data structures between [database connection | connections]
** to the same database. Sharing is enabled if the argument is true
** and disabled if the argument is false.)^
**
** ^Cache sharing is enabled and disabled for an entire process.
** This is a change as of SQLite [version 3.5.0] ([dateof:3.5.0]). 
** In prior versions of SQLite,
** sharing was enabled or disabled for each thread separately.
**
** ^(The cache sharing mode set by this interface effects all subsequent
** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
** Existing database connections continue use the sharing mode
** that was in effect at the time they were opened.)^
**
** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled
** successfully.  An [error code] is returned otherwise.)^
**
** ^Shared cache is disabled by default. But this might change in
** future releases of SQLite.  Applications that care about shared
** cache setting should set it explicitly.
**
** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0
** and will always return SQLITE_MISUSE. On those systems, 
** shared cache mode should be enabled per-database connection via 
** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE].
**
** This interface is threadsafe on processors where writing a
** 32-bit integer is atomic.
**
** See Also:  [SQLite Shared-Cache Mode]
*/
SQLITE_API int sqlite3_enable_shared_cache(int);

**
** See also: [sqlite3_db_release_memory()]
*/
SQLITE_API int sqlite3_release_memory(int);

/*
** CAPI3REF: Free Memory Used By A Database Connection
** METHOD: sqlite3
**
** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap
** memory as possible from database connection D. Unlike the
** [sqlite3_release_memory()] interface, this interface is in effect even
** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is
** omitted.
**
** See also: [sqlite3_release_memory()]
*/
SQLITE_API int sqlite3_db_release_memory(sqlite3*);

/*

** <li> An alternative page cache implementation is specified using
**      [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...).
** <li> The page cache allocates from its own memory pool supplied
**      by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than
**      from the heap.
** </ul>)^
**
** Beginning with SQLite [version 3.7.3] ([dateof:3.7.3]), 
** the soft heap limit is enforced
** regardless of whether or not the [SQLITE_ENABLE_MEMORY_MANAGEMENT]
** compile-time option is invoked.  With [SQLITE_ENABLE_MEMORY_MANAGEMENT],
** the soft heap limit is enforced on every memory allocation.  Without
** [SQLITE_ENABLE_MEMORY_MANAGEMENT], the soft heap limit is only enforced
** when memory is allocated by the page cache.  Testing suggests that because
** the page cache is the predominate memory user in SQLite, most
** applications will achieve adequate soft heap limit enforcement without

** [sqlite3_soft_heap_limit64()] interface rather than this one.
*/
SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N);


/*
** CAPI3REF: Extract Metadata About A Column Of A Table
** METHOD: sqlite3
**
** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns
** information about column C of table T in database D
** on [database connection] X.)^  ^The sqlite3_table_column_metadata()
** interface returns SQLITE_OK and fills in the non-NULL pointers in
** the final five arguments with appropriate values if the specified
** column exists.  ^The sqlite3_table_column_metadata() interface returns
** SQLITE_ERROR and if the specified column does not exist.
** ^If the column-name parameter to sqlite3_table_column_metadata() is a
** NULL pointer, then this routine simply checks for the existence of the
** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it
** does not.
**
** ^The column is identified by the second, third and fourth parameters to
** this function. ^(The second parameter is either the name of the database
** (i.e. "main", "temp", or an attached database) containing the specified
** table or NULL.)^ ^If it is NULL, then all attached databases are searched
** for the table using the same algorithm used by the database engine to
** resolve unqualified table references.
**
** ^The third and fourth parameters to this function are the table and column
** name of the desired column, respectively.

**
** ^Metadata is returned by writing to the memory locations passed as the 5th
** and subsequent parameters to this function. ^Any of these arguments may be
** NULL, in which case the corresponding element of metadata is omitted.
**
** ^(<blockquote>
** <table border="1">
** <tr><th> Parameter <th> Output<br>Type <th>  Description
**
** <tr><td> 5th <td> const char* <td> Data type
** <tr><td> 6th <td> const char* <td> Name of default collation sequence
** <tr><td> 7th <td> int         <td> True if column has a NOT NULL constraint
** <tr><td> 8th <td> int         <td> True if column is part of the PRIMARY KEY
** <tr><td> 9th <td> int         <td> True if column is [AUTOINCREMENT]
** </table>
** </blockquote>)^
**
** ^The memory pointed to by the character pointers returned for the
** declaration type and collation sequence is valid until the next
** call to any SQLite API function.
**
** ^If the specified table is actually a view, an [error code] is returned.
**
** ^If the specified column is "rowid", "oid" or "_rowid_" and the table 
** is not a [WITHOUT ROWID] table and an
** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
** parameters are set for the explicitly declared column. ^(If there is no
** [INTEGER PRIMARY KEY] column, then the outputs
** for the [rowid] are set as follows:
**
** <pre>
**     data type: "INTEGER"
**     collation sequence: "BINARY"
**     not null: 0
**     primary key: 1
**     auto increment: 0
** </pre>)^
**
** ^This function causes all database schemas to be read from disk and
** parsed, if that has not already been done, and returns an error if
** any errors are encountered while loading the schema.




*/
SQLITE_API int sqlite3_table_column_metadata(
  sqlite3 *db,                /* Connection handle */
  const char *zDbName,        /* Database name or NULL */
  const char *zTableName,     /* Table name */
  const char *zColumnName,    /* Column name */
  char const **pzDataType,    /* OUTPUT: Declared data type */
  char const **pzCollSeq,     /* OUTPUT: Collation sequence name */
  int *pNotNull,              /* OUTPUT: True if NOT NULL constraint exists */
  int *pPrimaryKey,           /* OUTPUT: True if column part of PK */
  int *pAutoinc               /* OUTPUT: True if column is auto-increment */
);

/*
** CAPI3REF: Load An Extension
** METHOD: sqlite3
**
** ^This interface loads an SQLite extension library from the named file.
**
** ^The sqlite3_load_extension() interface attempts to load an
** [SQLite extension] library contained in the file zFile.  If
** the file cannot be loaded directly, attempts are made to load
** with various operating-system specific extensions added.
** So for example, if "samplelib" cannot be loaded, then names like
** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might
** be tried also.
**
** ^The entry point is zProc.
** ^(zProc may be 0, in which case SQLite will try to come up with an
** entry point name on its own.  It first tries "sqlite3_extension_init".
** If that does not work, it constructs a name "sqlite3_X_init" where the
** X is consists of the lower-case equivalent of all ASCII alphabetic
** characters in the filename from the last "/" to the first following
** "." and omitting any initial "lib".)^
** ^The sqlite3_load_extension() interface returns
** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
** ^If an error occurs and pzErrMsg is not 0, then the
** [sqlite3_load_extension()] interface shall attempt to
** fill *pzErrMsg with error message text stored in memory
** obtained from [sqlite3_malloc()]. The calling function
** should free this memory by calling [sqlite3_free()].
**
** ^Extension loading must be enabled using
** [sqlite3_enable_load_extension()] or
** [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],1,NULL)
** prior to calling this API,
** otherwise an error will be returned.
**
** <b>Security warning:</b> It is recommended that the 
** [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method be used to enable only this
** interface.  The use of the [sqlite3_enable_load_extension()] interface
** should be avoided.  This will keep the SQL function [load_extension()]
** disabled and prevent SQL injections from giving attackers
** access to extension loading capabilities.
**
** See also the [load_extension() SQL function].
*/
SQLITE_API int sqlite3_load_extension(
  sqlite3 *db,          /* Load the extension into this database connection */
  const char *zFile,    /* Name of the shared library containing extension */
  const char *zProc,    /* Entry point.  Derived from zFile if 0 */
  char **pzErrMsg       /* Put error message here if not 0 */
);

/*
** CAPI3REF: Enable Or Disable Extension Loading
** METHOD: sqlite3
**
** ^So as not to open security holes in older applications that are
** unprepared to deal with [extension loading], and as a means of disabling
** [extension loading] while evaluating user-entered SQL, the following API
** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
**
** ^Extension loading is off by default.
** ^Call the sqlite3_enable_load_extension() routine with onoff==1
** to turn extension loading on and call it with onoff==0 to turn
** it back off again.
**
** ^This interface enables or disables both the C-API
** [sqlite3_load_extension()] and the SQL function [load_extension()].
** ^(Use [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],..)
** to enable or disable only the C-API.)^
**
** <b>Security warning:</b> It is recommended that extension loading
** be disabled using the [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method
** rather than this interface, so the [load_extension()] SQL function
** remains disabled. This will prevent SQL injections from giving attackers
** access to extension loading capabilities.
*/
SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);

/*
** CAPI3REF: Automatically Load Statically Linked Extensions
**
** ^This interface causes the xEntryPoint() function to be invoked for
** each new [database connection] that is created.  The idea here is that
** xEntryPoint() is the entry point for a statically linked [SQLite extension]
** that is to be automatically loaded into all new database connections.
**
** ^(Even though the function prototype shows that xEntryPoint() takes
** no arguments and returns void, SQLite invokes xEntryPoint() with three
** arguments and expects an integer result as if the signature of the
** entry point where as follows:
**
** <blockquote><pre>
** &nbsp;  int xEntryPoint(
** &nbsp;    sqlite3 *db,
** &nbsp;    const char **pzErrMsg,
** &nbsp;    const struct sqlite3_api_routines *pThunk

** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()],
** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail.
**
** ^Calling sqlite3_auto_extension(X) with an entry point X that is already
** on the list of automatic extensions is a harmless no-op. ^No entry point
** will be called more than once for each database connection that is opened.
**
** See also: [sqlite3_reset_auto_extension()]
** and [sqlite3_cancel_auto_extension()]
*/
SQLITE_API int sqlite3_auto_extension(void(*xEntryPoint)(void));

/*
** CAPI3REF: Cancel Automatic Extension Loading
**
** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the
** initialization routine X that was registered using a prior call to
** [sqlite3_auto_extension(X)].  ^The [sqlite3_cancel_auto_extension(X)]
** routine returns 1 if initialization routine X was successfully 
** unregistered and it returns 0 if X was not on the list of initialization
** routines.
*/
SQLITE_API int sqlite3_cancel_auto_extension(void(*xEntryPoint)(void));

/*
** CAPI3REF: Reset Automatic Extension Loading
**
** ^This interface disables all automatic extensions previously
** registered using [sqlite3_auto_extension()].
*/

** and makes other simplifications to the WHERE clause in an attempt to
** get as many WHERE clause terms into the form shown above as possible.
** ^The aConstraint[] array only reports WHERE clause terms that are
** relevant to the particular virtual table being queried.
**
** ^Information about the ORDER BY clause is stored in aOrderBy[].
** ^Each term of aOrderBy records a column of the ORDER BY clause.
**
** The colUsed field indicates which columns of the virtual table may be
** required by the current scan. Virtual table columns are numbered from
** zero in the order in which they appear within the CREATE TABLE statement
** passed to sqlite3_declare_vtab(). For the first 63 columns (columns 0-62),
** the corresponding bit is set within the colUsed mask if the column may be
** required by SQLite. If the table has at least 64 columns and any column
** to the right of the first 63 is required, then bit 63 of colUsed is also
** set. In other words, column iCol may be required if the expression
** (colUsed & ((sqlite3_uint64)1 << (iCol>=63 ? 63 : iCol))) evaluates to 
** non-zero.
**
** The [xBestIndex] method must fill aConstraintUsage[] with information
** about what parameters to pass to xFilter.  ^If argvIndex>0 then
** the right-hand side of the corresponding aConstraint[] is evaluated
** and becomes the argvIndex-th entry in argv.  ^(If aConstraintUsage[].omit
** is true, then the constraint is assumed to be fully handled by the
** virtual table and is not checked again by SQLite.)^
**
** ^The idxNum and idxPtr values are recorded and passed into the
** [xFilter] method.
** ^[sqlite3_free()] is used to free idxPtr if and only if
** needToFreeIdxPtr is true.
**
** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
** the correct order to satisfy the ORDER BY clause so that no separate
** sorting step is required.
**
** ^The estimatedCost value is an estimate of the cost of a particular
** strategy. A cost of N indicates that the cost of the strategy is similar
** to a linear scan of an SQLite table with N rows. A cost of log(N) 
** indicates that the expense of the operation is similar to that of a
** binary search on a unique indexed field of an SQLite table with N rows.
**
** ^The estimatedRows value is an estimate of the number of rows that
** will be returned by the strategy.
**
** The xBestIndex method may optionally populate the idxFlags field with a 
** mask of SQLITE_INDEX_SCAN_* flags. Currently there is only one such flag -
** SQLITE_INDEX_SCAN_UNIQUE. If the xBestIndex method sets this flag, SQLite
** assumes that the strategy may visit at most one row. 
**
** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then
** SQLite also assumes that if a call to the xUpdate() method is made as
** part of the same statement to delete or update a virtual table row and the
** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback
** any database changes. In other words, if the xUpdate() returns
** SQLITE_CONSTRAINT, the database contents must be exactly as they were
** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not
** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by
** the xUpdate method are automatically rolled back by SQLite.
**
** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info
** structure for SQLite [version 3.8.2] ([dateof:3.8.2]). 
** If a virtual table extension is
** used with an SQLite version earlier than 3.8.2, the results of attempting 
** to read or write the estimatedRows field are undefined (but are likely 
** to included crashing the application). The estimatedRows field should
** therefore only be used if [sqlite3_libversion_number()] returns a
** value greater than or equal to 3008002. Similarly, the idxFlags field
** was added for [version 3.9.0] ([dateof:3.9.0]). 
** It may therefore only be used if
** sqlite3_libversion_number() returns a value greater than or equal to
** 3009000.
*/
struct sqlite3_index_info {
  /* Inputs */
  int nConstraint;           /* Number of entries in aConstraint */
  struct sqlite3_index_constraint {
     int iColumn;              /* Column constrained.  -1 for ROWID */
     unsigned char op;         /* Constraint operator */
     unsigned char usable;     /* True if this constraint is usable */
     int iTermOffset;          /* Used internally - xBestIndex should ignore */
  } *aConstraint;            /* Table of WHERE clause constraints */
  int nOrderBy;              /* Number of terms in the ORDER BY clause */
  struct sqlite3_index_orderby {
     int iColumn;              /* Column number */
     unsigned char desc;       /* True for DESC.  False for ASC. */
  } *aOrderBy;               /* The ORDER BY clause */
  /* Outputs */
  struct sqlite3_index_constraint_usage {
    int argvIndex;           /* if >0, constraint is part of argv to xFilter */
    unsigned char omit;      /* Do not code a test for this constraint */
  } *aConstraintUsage;
  int idxNum;                /* Number used to identify the index */
  char *idxStr;              /* String, possibly obtained from sqlite3_malloc */
  int needToFreeIdxStr;      /* Free idxStr using sqlite3_free() if true */
  int orderByConsumed;       /* True if output is already ordered */
  double estimatedCost;           /* Estimated cost of using this index */
  /* Fields below are only available in SQLite 3.8.2 and later */
  sqlite3_int64 estimatedRows;    /* Estimated number of rows returned */
  /* Fields below are only available in SQLite 3.9.0 and later */
  int idxFlags;              /* Mask of SQLITE_INDEX_SCAN_* flags */
  /* Fields below are only available in SQLite 3.10.0 and later */
  sqlite3_uint64 colUsed;    /* Input: Mask of columns used by statement */
};

/*
** CAPI3REF: Virtual Table Scan Flags
*/
#define SQLITE_INDEX_SCAN_UNIQUE      1     /* Scan visits at most 1 row */

/*
** CAPI3REF: Virtual Table Constraint Operator Codes
**
** These macros defined the allowed values for the
** [sqlite3_index_info].aConstraint[].op field.  Each value represents
** an operator that is part of a constraint term in the wHERE clause of
** a query that uses a [virtual table].
*/
#define SQLITE_INDEX_CONSTRAINT_EQ      2
#define SQLITE_INDEX_CONSTRAINT_GT      4
#define SQLITE_INDEX_CONSTRAINT_LE      8
#define SQLITE_INDEX_CONSTRAINT_LT     16
#define SQLITE_INDEX_CONSTRAINT_GE     32
#define SQLITE_INDEX_CONSTRAINT_MATCH  64
#define SQLITE_INDEX_CONSTRAINT_LIKE   65
#define SQLITE_INDEX_CONSTRAINT_GLOB   66
#define SQLITE_INDEX_CONSTRAINT_REGEXP 67

/*
** CAPI3REF: Register A Virtual Table Implementation
** METHOD: sqlite3
**
** ^These routines are used to register a new [virtual table module] name.
** ^Module names must be registered before
** creating a new [virtual table] using the module and before using a
** preexisting [virtual table] for the module.
**
** ^The module name is registered on the [database connection] specified

** take care that any prior string is freed by a call to [sqlite3_free()]
** prior to assigning a new string to zErrMsg.  ^After the error message
** is delivered up to the client application, the string will be automatically
** freed by sqlite3_free() and the zErrMsg field will be zeroed.
*/
struct sqlite3_vtab {
  const sqlite3_module *pModule;  /* The module for this virtual table */
  int nRef;                       /* Number of open cursors */
  char *zErrMsg;                  /* Error message from sqlite3_mprintf() */
  /* Virtual table implementations will typically add additional fields */
};

/*
** CAPI3REF: Virtual Table Cursor Object
** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}

** to declare the format (the names and datatypes of the columns) of
** the virtual tables they implement.
*/
SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL);

/*
** CAPI3REF: Overload A Function For A Virtual Table
** METHOD: sqlite3
**
** ^(Virtual tables can provide alternative implementations of functions
** using the [xFindFunction] method of the [virtual table module].  
** But global versions of those functions
** must exist in order to be overloaded.)^
**
** ^(This API makes sure a global version of a function with a particular

** can be used to read or write small subsections of the BLOB.
** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
*/
typedef struct sqlite3_blob sqlite3_blob;

/*
** CAPI3REF: Open A BLOB For Incremental I/O
** METHOD: sqlite3
** CONSTRUCTOR: sqlite3_blob
**
** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located
** in row iRow, column zColumn, table zTable in database zDb;
** in other words, the same BLOB that would be selected by:
**
** <pre>
**     SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
** </pre>)^
**






** ^(Parameter zDb is not the filename that contains the database, but 
** rather the symbolic name of the database. For attached databases, this is
** the name that appears after the AS keyword in the [ATTACH] statement.
** For the main database file, the database name is "main". For TEMP
** tables, the database name is "temp".)^
**
** ^If the flags parameter is non-zero, then the BLOB is opened for read
** and write access. ^If the flags parameter is zero, the BLOB is opened for
** read-only access.
**
** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is stored
** in *ppBlob. Otherwise an [error code] is returned and, unless the error
** code is SQLITE_MISUSE, *ppBlob is set to NULL.)^ ^This means that, provided
** the API is not misused, it is always safe to call [sqlite3_blob_close()] 
** on *ppBlob after this function it returns.
**
** This function fails with SQLITE_ERROR if any of the following are true:
** <ul>
**   <li> ^(Database zDb does not exist)^, 
**   <li> ^(Table zTable does not exist within database zDb)^, 
**   <li> ^(Table zTable is a WITHOUT ROWID table)^, 
**   <li> ^(Column zColumn does not exist)^,
**   <li> ^(Row iRow is not present in the table)^,
**   <li> ^(The specified column of row iRow contains a value that is not
**         a TEXT or BLOB value)^,
**   <li> ^(Column zColumn is part of an index, PRIMARY KEY or UNIQUE 
**         constraint and the blob is being opened for read/write access)^,
**   <li> ^([foreign key constraints | Foreign key constraints] are enabled, 
**         column zColumn is part of a [child key] definition and the blob is
**         being opened for read/write access)^.
** </ul>
**
** ^Unless it returns SQLITE_MISUSE, this function sets the 
** [database connection] error code and message accessible via 
** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. 



**
**
** ^(If the row that a BLOB handle points to is modified by an
** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
** then the BLOB handle is marked as "expired".
** This is true if any column of the row is changed, even a column
** other than the one the BLOB handle is open on.)^
** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
** an expired BLOB handle fail with a return code of [SQLITE_ABORT].
** ^(Changes written into a BLOB prior to the BLOB expiring are not
** rolled back by the expiration of the BLOB.  Such changes will eventually
** commit if the transaction continues to completion.)^
**
** ^Use the [sqlite3_blob_bytes()] interface to determine the size of
** the opened blob.  ^The size of a blob may not be changed by this
** interface.  Use the [UPDATE] SQL command to change the size of a
** blob.
**
** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
** and the built-in [zeroblob] SQL function may be used to create a 
** zero-filled blob to read or write using the incremental-blob interface.

**
** To avoid a resource leak, every open [BLOB handle] should eventually
** be released by a call to [sqlite3_blob_close()].
*/
SQLITE_API int sqlite3_blob_open(
  sqlite3*,
  const char *zDb,
  const char *zTable,
  const char *zColumn,
  sqlite3_int64 iRow,
  int flags,
  sqlite3_blob **ppBlob
);

/*
** CAPI3REF: Move a BLOB Handle to a New Row
** METHOD: sqlite3_blob
**
** ^This function is used to move an existing blob handle so that it points
** to a different row of the same database table. ^The new row is identified
** by the rowid value passed as the second argument. Only the row can be
** changed. ^The database, table and column on which the blob handle is open
** remain the same. Moving an existing blob handle to a new row can be
** faster than closing the existing handle and opening a new one.
**
** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] -
** it must exist and there must be either a blob or text value stored in
** the nominated column.)^ ^If the new row is not present in the table, or if
** it does not contain a blob or text value, or if another error occurs, an
** SQLite error code is returned and the blob handle is considered aborted.
** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or
** [sqlite3_blob_reopen()] on an aborted blob handle immediately return
** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle
** always returns zero.
**
** ^This function sets the database handle error code and message.
*/
SQLITE_API int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64);

/*
** CAPI3REF: Close A BLOB Handle
** DESTRUCTOR: sqlite3_blob
**
** ^This function closes an open [BLOB handle]. ^(The BLOB handle is closed
** unconditionally.  Even if this routine returns an error code, the 
** handle is still closed.)^
**
** ^If the blob handle being closed was opened for read-write access, and if
** the database is in auto-commit mode and there are no other open read-write
** blob handles or active write statements, the current transaction is
** committed. ^If an error occurs while committing the transaction, an error
** code is returned and the transaction rolled back.



**
** Calling this function with an argument that is not a NULL pointer or an



** open blob handle results in undefined behaviour. ^Calling this routine 



** with a null pointer (such as would be returned by a failed call to 
** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function
** is passed a valid open blob handle, the values returned by the 
** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning.
*/
SQLITE_API int sqlite3_blob_close(sqlite3_blob *);

/*
** CAPI3REF: Return The Size Of An Open BLOB
** METHOD: sqlite3_blob
**
** ^Returns the size in bytes of the BLOB accessible via the 
** successfully opened [BLOB handle] in its only argument.  ^The
** incremental blob I/O routines can only read or overwriting existing
** blob content; they cannot change the size of a blob.
**
** This routine only works on a [BLOB handle] which has been created
** by a prior successful call to [sqlite3_blob_open()] and which has not
** been closed by [sqlite3_blob_close()].  Passing any other pointer in
** to this routine results in undefined and probably undesirable behavior.
*/
SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *);

/*
** CAPI3REF: Read Data From A BLOB Incrementally
** METHOD: sqlite3_blob
**
** ^(This function is used to read data from an open [BLOB handle] into a
** caller-supplied buffer. N bytes of data are copied into buffer Z
** from the open BLOB, starting at offset iOffset.)^
**
** ^If offset iOffset is less than N bytes from the end of the BLOB,
** [SQLITE_ERROR] is returned and no data is read.  ^If N or iOffset is

**
** See also: [sqlite3_blob_write()].
*/
SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);

/*
** CAPI3REF: Write Data Into A BLOB Incrementally
** METHOD: sqlite3_blob
**
** ^(This function is used to write data into an open [BLOB handle] from a
** caller-supplied buffer. N bytes of data are copied from the buffer Z
** into the open BLOB, starting at offset iOffset.)^
**
** ^(On success, sqlite3_blob_write() returns SQLITE_OK.
** Otherwise, an  [error code] or an [extended error code] is returned.)^
** ^Unless SQLITE_MISUSE is returned, this function sets the 
** [database connection] error code and message accessible via 
** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. 
**
** ^If the [BLOB handle] passed as the first argument was not opened for
** writing (the flags parameter to [sqlite3_blob_open()] was zero),
** this function returns [SQLITE_READONLY].
**
** This function may only modify the contents of the BLOB; it is
** not possible to increase the size of a BLOB using this API.
** ^If offset iOffset is less than N bytes from the end of the BLOB,
** [SQLITE_ERROR] is returned and no data is written. The size of the 

** BLOB (and hence the maximum value of N+iOffset) can be determined 
** using the [sqlite3_blob_bytes()] interface. ^If N or iOffset are less 
** than zero [SQLITE_ERROR] is returned and no data is written.
**
** ^An attempt to write to an expired [BLOB handle] fails with an
** error code of [SQLITE_ABORT].  ^Writes to the BLOB that occurred
** before the [BLOB handle] expired are not rolled back by the
** expiration of the handle, though of course those changes might
** have been overwritten by the statement that expired the BLOB handle
** or by other independent statements.
**



** This routine only works on a [BLOB handle] which has been created
** by a prior successful call to [sqlite3_blob_open()] and which has not
** been closed by [sqlite3_blob_close()].  Passing any other pointer in
** to this routine results in undefined and probably undesirable behavior.
**
** See also: [sqlite3_blob_read()].
*/

** The SQLite core uses these routines for thread
** synchronization. Though they are intended for internal
** use by SQLite, code that links against SQLite is
** permitted to use any of these routines.
**
** The SQLite source code contains multiple implementations
** of these mutex routines.  An appropriate implementation
** is selected automatically at compile-time.  The following
** implementations are available in the SQLite core:
**
** <ul>
** <li>   SQLITE_MUTEX_PTHREADS
** <li>   SQLITE_MUTEX_W32
** <li>   SQLITE_MUTEX_NOOP
** </ul>
**
** The SQLITE_MUTEX_NOOP implementation is a set of routines
** that does no real locking and is appropriate for use in
** a single-threaded application.  The SQLITE_MUTEX_PTHREADS and
** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix
** and Windows.
**
** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
** implementation is included with the library. In this case the
** application must supply a custom mutex implementation using the
** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
** before calling sqlite3_initialize() or any other public sqlite3_
** function that calls sqlite3_initialize().
**
** ^The sqlite3_mutex_alloc() routine allocates a new
** mutex and returns a pointer to it. ^The sqlite3_mutex_alloc()
** routine returns NULL if it is unable to allocate the requested
** mutex.  The argument to sqlite3_mutex_alloc() must one of these
** integer constants:
**
** <ul>
** <li>  SQLITE_MUTEX_FAST
** <li>  SQLITE_MUTEX_RECURSIVE
** <li>  SQLITE_MUTEX_STATIC_MASTER
** <li>  SQLITE_MUTEX_STATIC_MEM
** <li>  SQLITE_MUTEX_STATIC_OPEN
** <li>  SQLITE_MUTEX_STATIC_PRNG
** <li>  SQLITE_MUTEX_STATIC_LRU
** <li>  SQLITE_MUTEX_STATIC_PMEM
** <li>  SQLITE_MUTEX_STATIC_APP1
** <li>  SQLITE_MUTEX_STATIC_APP2
** <li>  SQLITE_MUTEX_STATIC_APP3
** <li>  SQLITE_MUTEX_STATIC_VFS1
** <li>  SQLITE_MUTEX_STATIC_VFS2
** <li>  SQLITE_MUTEX_STATIC_VFS3
** </ul>
**
** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE)
** cause sqlite3_mutex_alloc() to create
** a new mutex.  ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
** The mutex implementation does not need to make a distinction
** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
** not want to.  SQLite will only request a recursive mutex in
** cases where it really needs one.  If a faster non-recursive mutex
** implementation is available on the host platform, the mutex subsystem
** might return such a mutex in response to SQLITE_MUTEX_FAST.
**
** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other
** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return
** a pointer to a static preexisting mutex.  ^Nine static mutexes are
** used by the current version of SQLite.  Future versions of SQLite
** may add additional static mutexes.  Static mutexes are for internal
** use by SQLite only.  Applications that use SQLite mutexes should
** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
** SQLITE_MUTEX_RECURSIVE.
**
** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
** returns a different mutex on every call.  ^For the static
** mutex types, the same mutex is returned on every call that has
** the same type number.
**
** ^The sqlite3_mutex_free() routine deallocates a previously


** allocated dynamic mutex.  Attempting to deallocate a static
** mutex results in undefined behavior.

**
** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
** to enter a mutex.  ^If another thread is already within the mutex,
** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
** SQLITE_BUSY.  ^The sqlite3_mutex_try() interface returns [SQLITE_OK]
** upon successful entry.  ^(Mutexes created using
** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
** In such cases, the
** mutex must be exited an equal number of times before another thread
** can enter.)^  If the same thread tries to enter any mutex other
** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined.


**
** ^(Some systems (for example, Windows 95) do not support the operation
** implemented by sqlite3_mutex_try().  On those systems, sqlite3_mutex_try()
** will always return SQLITE_BUSY. The SQLite core only ever uses
** sqlite3_mutex_try() as an optimization so this is acceptable 
** behavior.)^
**
** ^The sqlite3_mutex_leave() routine exits a mutex that was
** previously entered by the same thread.   The behavior
** is undefined if the mutex is not currently entered by the
** calling thread or is not currently allocated.

**
** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
** sqlite3_mutex_leave() is a NULL pointer, then all three routines
** behave as no-ops.
**
** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
*/
SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int);
SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*);
SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*);
SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*);
SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*);

/*
** CAPI3REF: Mutex Methods Object
**
** An instance of this structure defines the low-level routines
** used to allocate and use mutexes.
**
** Usually, the default mutex implementations provided by SQLite are
** sufficient, however the application has the option of substituting a custom
** implementation for specialized deployments or systems for which SQLite
** does not provide a suitable implementation. In this case, the application
** creates and populates an instance of this structure to pass
** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
** Additionally, an instance of this structure can be used as an
** output variable when querying the system for the current mutex
** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
**
** ^The xMutexInit method defined by this structure is invoked as

** above silently ignore any invocations that pass a NULL pointer instead
** of a valid mutex handle. The implementations of the methods defined
** by this structure are not required to handle this case, the results
** of passing a NULL pointer instead of a valid mutex handle are undefined
** (i.e. it is acceptable to provide an implementation that segfaults if
** it is passed a NULL pointer).
**
** The xMutexInit() method must be threadsafe.  It must be harmless to
** invoke xMutexInit() multiple times within the same process and without
** intervening calls to xMutexEnd().  Second and subsequent calls to
** xMutexInit() must be no-ops.
**
** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
** and its associates).  Similarly, xMutexAlloc() must not use SQLite memory
** allocation for a static mutex.  ^However xMutexAlloc() may use SQLite
** memory allocation for a fast or recursive mutex.
**
** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
** called, but only if the prior call to xMutexInit returned SQLITE_OK.
** If xMutexInit fails in any way, it is expected to clean up after itself
** prior to returning.

  int (*xMutexNotheld)(sqlite3_mutex *);
};

/*
** CAPI3REF: Mutex Verification Routines
**
** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
** are intended for use inside assert() statements.  The SQLite core
** never uses these routines except inside an assert() and applications
** are advised to follow the lead of the core.  The SQLite core only
** provides implementations for these routines when it is compiled
** with the SQLITE_DEBUG flag.  External mutex implementations
** are only required to provide these routines if SQLITE_DEBUG is
** defined and if NDEBUG is not defined.
**
** These routines should return true if the mutex in their argument
** is held or not held, respectively, by the calling thread.
**
** The implementation is not required to provide versions of these
** routines that actually work. If the implementation does not provide working
** versions of these routines, it should at least provide stubs that always
** return true so that one does not get spurious assertion failures.
**
** If the argument to sqlite3_mutex_held() is a NULL pointer then
** the routine should return 1.   This seems counter-intuitive since
** clearly the mutex cannot be held if it does not exist.  But
** the reason the mutex does not exist is because the build is not
** using mutexes.  And we do not want the assert() containing the
** call to sqlite3_mutex_held() to fail, so a non-zero return is
** the appropriate thing to do.  The sqlite3_mutex_notheld()
** interface should also return 1 when given a NULL pointer.
*/
#ifndef NDEBUG
SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*);
SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*);
#endif

*/
#define SQLITE_MUTEX_FAST             0
#define SQLITE_MUTEX_RECURSIVE        1
#define SQLITE_MUTEX_STATIC_MASTER    2
#define SQLITE_MUTEX_STATIC_MEM       3  /* sqlite3_malloc() */
#define SQLITE_MUTEX_STATIC_MEM2      4  /* NOT USED */
#define SQLITE_MUTEX_STATIC_OPEN      4  /* sqlite3BtreeOpen() */
#define SQLITE_MUTEX_STATIC_PRNG      5  /* sqlite3_randomness() */
#define SQLITE_MUTEX_STATIC_LRU       6  /* lru page list */
#define SQLITE_MUTEX_STATIC_LRU2      7  /* NOT USED */
#define SQLITE_MUTEX_STATIC_PMEM      7  /* sqlite3PageMalloc() */
#define SQLITE_MUTEX_STATIC_APP1      8  /* For use by application */
#define SQLITE_MUTEX_STATIC_APP2      9  /* For use by application */
#define SQLITE_MUTEX_STATIC_APP3     10  /* For use by application */
#define SQLITE_MUTEX_STATIC_VFS1     11  /* For use by built-in VFS */
#define SQLITE_MUTEX_STATIC_VFS2     12  /* For use by extension VFS */
#define SQLITE_MUTEX_STATIC_VFS3     13  /* For use by application VFS */

/*
** CAPI3REF: Retrieve the mutex for a database connection
** METHOD: sqlite3
**
** ^This interface returns a pointer the [sqlite3_mutex] object that 
** serializes access to the [database connection] given in the argument
** when the [threading mode] is Serialized.
** ^If the [threading mode] is Single-thread or Multi-thread then this
** routine returns a NULL pointer.
*/
SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*);

/*
** CAPI3REF: Low-Level Control Of Database Files
** METHOD: sqlite3
**
** ^The [sqlite3_file_control()] interface makes a direct call to the
** xFileControl method for the [sqlite3_io_methods] object associated
** with a particular database identified by the second argument. ^The
** name of the database is "main" for the main database or "temp" for the
** TEMP database, or the name that appears after the AS keyword for
** databases that are added using the [ATTACH] SQL command.

#define SQLITE_TESTCTRL_ASSERT                  12
#define SQLITE_TESTCTRL_ALWAYS                  13
#define SQLITE_TESTCTRL_RESERVE                 14
#define SQLITE_TESTCTRL_OPTIMIZATIONS           15
#define SQLITE_TESTCTRL_ISKEYWORD               16
#define SQLITE_TESTCTRL_SCRATCHMALLOC           17
#define SQLITE_TESTCTRL_LOCALTIME_FAULT         18
#define SQLITE_TESTCTRL_EXPLAIN_STMT            19  /* NOT USED */
#define SQLITE_TESTCTRL_ONCE_RESET_THRESHOLD    19
#define SQLITE_TESTCTRL_NEVER_CORRUPT           20
#define SQLITE_TESTCTRL_VDBE_COVERAGE           21
#define SQLITE_TESTCTRL_BYTEORDER               22
#define SQLITE_TESTCTRL_ISINIT                  23
#define SQLITE_TESTCTRL_SORTER_MMAP             24
#define SQLITE_TESTCTRL_IMPOSTER                25
#define SQLITE_TESTCTRL_LAST                    25

/*
** CAPI3REF: SQLite Runtime Status
**
** ^These interfaces are used to retrieve runtime status information
** about the performance of SQLite, and optionally to reset various
** highwater marks.  ^The first argument is an integer code for
** the specific parameter to measure.  ^(Recognized integer codes
** are of the form [status parameters | SQLITE_STATUS_...].)^
** ^The current value of the parameter is returned into *pCurrent.
** ^The highest recorded value is returned in *pHighwater.  ^If the
** resetFlag is true, then the highest record value is reset after
** *pHighwater is written.  ^(Some parameters do not record the highest
** value.  For those parameters
** nothing is written into *pHighwater and the resetFlag is ignored.)^
** ^(Other parameters record only the highwater mark and not the current
** value.  For these latter parameters nothing is written into *pCurrent.)^
**
** ^The sqlite3_status() and sqlite3_status64() routines return
** SQLITE_OK on success and a non-zero [error code] on failure.
**

** If either the current value or the highwater mark is too large to
** be represented by a 32-bit integer, then the values returned by



** sqlite3_status() are undefined.
**
** See also: [sqlite3_db_status()]
*/
SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
SQLITE_API int sqlite3_status64(
  int op,
  sqlite3_int64 *pCurrent,
  sqlite3_int64 *pHighwater,
  int resetFlag
);


/*
** CAPI3REF: Status Parameters
** KEYWORDS: {status parameters}
**
** These integer constants designate various run-time status parameters

** [[SQLITE_STATUS_SCRATCH_SIZE]] ^(<dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
** <dd>This parameter records the largest memory allocation request
** handed to [scratch memory allocator].  Only the value returned in the
** *pHighwater parameter to [sqlite3_status()] is of interest.  
** The value written into the *pCurrent parameter is undefined.</dd>)^
**
** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt>
** <dd>The *pHighwater parameter records the deepest parser stack. 
** The *pCurrent value is undefined.  The *pHighwater value is only
** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^
** </dl>
**
** New status parameters may be added from time to time.
*/
#define SQLITE_STATUS_MEMORY_USED          0
#define SQLITE_STATUS_PAGECACHE_USED       1
#define SQLITE_STATUS_PAGECACHE_OVERFLOW   2
#define SQLITE_STATUS_SCRATCH_USED         3
#define SQLITE_STATUS_SCRATCH_OVERFLOW     4
#define SQLITE_STATUS_MALLOC_SIZE          5
#define SQLITE_STATUS_PARSER_STACK         6
#define SQLITE_STATUS_PAGECACHE_SIZE       7
#define SQLITE_STATUS_SCRATCH_SIZE         8
#define SQLITE_STATUS_MALLOC_COUNT         9

/*
** CAPI3REF: Database Connection Status
** METHOD: sqlite3
**
** ^This interface is used to retrieve runtime status information 
** about a single [database connection].  ^The first argument is the
** database connection object to be interrogated.  ^The second argument
** is an integer constant, taken from the set of
** [SQLITE_DBSTATUS options], that
** determines the parameter to interrogate.  The set of 

** <dd>This parameter returns the number malloc attempts that might have
** been satisfied using lookaside memory but failed due to all lookaside
** memory already being in use.
** Only the high-water value is meaningful;
** the current value is always zero.)^
**
** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt>
** <dd>This parameter returns the approximate number of bytes of heap
** memory used by all pager caches associated with the database connection.)^
** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.
**
** [[SQLITE_DBSTATUS_CACHE_USED_SHARED]] 
** ^(<dt>SQLITE_DBSTATUS_CACHE_USED_SHARED</dt>
** <dd>This parameter is similar to DBSTATUS_CACHE_USED, except that if a
** pager cache is shared between two or more connections the bytes of heap
** memory used by that pager cache is divided evenly between the attached
** connections.)^  In other words, if none of the pager caches associated
** with the database connection are shared, this request returns the same
** value as DBSTATUS_CACHE_USED. Or, if one or more or the pager caches are
** shared, the value returned by this call will be smaller than that returned
** by DBSTATUS_CACHE_USED. ^The highwater mark associated with
** SQLITE_DBSTATUS_CACHE_USED_SHARED is always 0.
**
** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt>
** <dd>This parameter returns the approximate number of bytes of heap
** memory used to store the schema for all databases associated
** with the connection - main, temp, and any [ATTACH]-ed databases.)^ 
** ^The full amount of memory used by the schemas is reported, even if the
** schema memory is shared with other database connections due to
** [shared cache mode] being enabled.
** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0.
**
** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt>
** <dd>This parameter returns the approximate number of bytes of heap
** and lookaside memory used by all prepared statements associated with
** the database connection.)^
** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0.
** </dd>
**
** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt>
** <dd>This parameter returns the number of pager cache hits that have

** wal file in wal mode databases, or the number of pages written to the
** database file in rollback mode databases. Any pages written as part of
** transaction rollback or database recovery operations are not included.
** If an IO or other error occurs while writing a page to disk, the effect
** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The
** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0.
** </dd>
**
** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt>
** <dd>This parameter returns zero for the current value if and only if
** all foreign key constraints (deferred or immediate) have been
** resolved.)^  ^The highwater mark is always 0.
** </dd>
** </dl>
*/
#define SQLITE_DBSTATUS_LOOKASIDE_USED       0
#define SQLITE_DBSTATUS_CACHE_USED           1
#define SQLITE_DBSTATUS_SCHEMA_USED          2
#define SQLITE_DBSTATUS_STMT_USED            3
#define SQLITE_DBSTATUS_LOOKASIDE_HIT        4
#define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE  5
#define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL  6
#define SQLITE_DBSTATUS_CACHE_HIT            7
#define SQLITE_DBSTATUS_CACHE_MISS           8
#define SQLITE_DBSTATUS_CACHE_WRITE          9
#define SQLITE_DBSTATUS_DEFERRED_FKS        10
#define SQLITE_DBSTATUS_CACHE_USED_SHARED   11
#define SQLITE_DBSTATUS_MAX                 11   /* Largest defined DBSTATUS */


/*
** CAPI3REF: Prepared Statement Status
** METHOD: sqlite3_stmt
**
** ^(Each prepared statement maintains various
** [SQLITE_STMTSTATUS counters] that measure the number
** of times it has performed specific operations.)^  These counters can
** be used to monitor the performance characteristics of the prepared
** statements.  For example, if the number of table steps greatly exceeds
** the number of table searches or result rows, that would tend to indicate

**
** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt>
** <dd>^This is the number of rows inserted into transient indices that
** were created automatically in order to help joins run faster.
** A non-zero value in this counter may indicate an opportunity to
** improvement performance by adding permanent indices that do not
** need to be reinitialized each time the statement is run.</dd>
**
** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt>
** <dd>^This is the number of virtual machine operations executed
** by the prepared statement if that number is less than or equal
** to 2147483647.  The number of virtual machine operations can be 
** used as a proxy for the total work done by the prepared statement.
** If the number of virtual machine operations exceeds 2147483647
** then the value returned by this statement status code is undefined.
** </dd>
** </dl>
*/
#define SQLITE_STMTSTATUS_FULLSCAN_STEP     1
#define SQLITE_STMTSTATUS_SORT              2
#define SQLITE_STMTSTATUS_AUTOINDEX         3
#define SQLITE_STMTSTATUS_VM_STEP           4

/*
** CAPI3REF: Custom Page Cache Object
**
** The sqlite3_pcache type is opaque.  It is implemented by
** the pluggable module.  The SQLite core has no knowledge of
** its size or internal structure and never deals with the

** If the requested page is already in the page cache, then the page cache
** implementation must return a pointer to the page buffer with its content
** intact.  If the requested page is not already in the cache, then the
** cache implementation should use the value of the createFlag
** parameter to help it determined what action to take:
**
** <table border=1 width=85% align=center>
** <tr><th> createFlag <th> Behavior when page is not already in cache
** <tr><td> 0 <td> Do not allocate a new page.  Return NULL.
** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so.
**                 Otherwise return NULL.
** <tr><td> 2 <td> Make every effort to allocate a new page.  Only return
**                 NULL if allocating a new page is effectively impossible.
** </table>
**

** an [ATTACH] statement for an attached database.
** ^The S and M arguments passed to 
** sqlite3_backup_init(D,N,S,M) identify the [database connection]
** and database name of the source database, respectively.
** ^The source and destination [database connections] (parameters S and D)
** must be different or else sqlite3_backup_init(D,N,S,M) will fail with
** an error.
**
** ^A call to sqlite3_backup_init() will fail, returning NULL, if 
** there is already a read or read-write transaction open on the 
** destination database.
**
** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is
** returned and an error code and error message are stored in the
** destination [database connection] D.
** ^The error code and message for the failed call to sqlite3_backup_init()
** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or
** [sqlite3_errmsg16()] functions.

** sqlite3_backup_step() call on the same [sqlite3_backup] object, then
** sqlite3_backup_finish() returns the corresponding [error code].
**
** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step()
** is not a permanent error and does not affect the return value of
** sqlite3_backup_finish().
**
** [[sqlite3_backup_remaining()]] [[sqlite3_backup_pagecount()]]
** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b>
**
** ^The sqlite3_backup_remaining() routine returns the number of pages still
** to be backed up at the conclusion of the most recent sqlite3_backup_step().
** ^The sqlite3_backup_pagecount() routine returns the total number of pages
** in the source database at the conclusion of the most recent
** sqlite3_backup_step().


** ^(The values returned by these functions are only updated by
** sqlite3_backup_step(). If the source database is modified in a way that

** changes the size of the source database or the number of pages remaining,
** those changes are not reflected in the output of sqlite3_backup_pagecount()
** and sqlite3_backup_remaining() until after the next
** sqlite3_backup_step().)^
**
** <b>Concurrent Usage of Database Handles</b>
**
** ^The source [database connection] may be used by the application for other
** purposes while a backup operation is underway or being initialized.
** ^If SQLite is compiled and configured to support threadsafe database
** connections, then the source database connection may be used concurrently

SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage);
SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p);
SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p);
SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p);

/*
** CAPI3REF: Unlock Notification
** METHOD: sqlite3
**
** ^When running in shared-cache mode, a database operation may fail with
** an [SQLITE_LOCKED] error if the required locks on the shared-cache or
** individual tables within the shared-cache cannot be obtained. See
** [SQLite Shared-Cache Mode] for a description of shared-cache locking. 
** ^This API may be used to register a callback that SQLite will invoke 
** when the connection currently holding the required lock relinquishes it.

** and extensions to compare the contents of two buffers containing UTF-8
** strings in a case-independent fashion, using the same definition of "case
** independence" that SQLite uses internally when comparing identifiers.
*/
SQLITE_API int sqlite3_stricmp(const char *, const char *);
SQLITE_API int sqlite3_strnicmp(const char *, const char *, int);

/*
** CAPI3REF: String Globbing
*
** ^The [sqlite3_strglob(P,X)] interface returns zero if and only if
** string X matches the [GLOB] pattern P.
** ^The definition of [GLOB] pattern matching used in
** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the
** SQL dialect understood by SQLite.  ^The [sqlite3_strglob(P,X)] function
** is case sensitive.
**
** Note that this routine returns zero on a match and non-zero if the strings
** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
**
** See also: [sqlite3_strlike()].
*/
SQLITE_API int sqlite3_strglob(const char *zGlob, const char *zStr);

/*
** CAPI3REF: String LIKE Matching
*
** ^The [sqlite3_strlike(P,X,E)] interface returns zero if and only if
** string X matches the [LIKE] pattern P with escape character E.
** ^The definition of [LIKE] pattern matching used in
** [sqlite3_strlike(P,X,E)] is the same as for the "X LIKE P ESCAPE E"
** operator in the SQL dialect understood by SQLite.  ^For "X LIKE P" without
** the ESCAPE clause, set the E parameter of [sqlite3_strlike(P,X,E)] to 0.
** ^As with the LIKE operator, the [sqlite3_strlike(P,X,E)] function is case
** insensitive - equivalent upper and lower case ASCII characters match
** one another.
**
** ^The [sqlite3_strlike(P,X,E)] function matches Unicode characters, though
** only ASCII characters are case folded.
**
** Note that this routine returns zero on a match and non-zero if the strings
** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
**
** See also: [sqlite3_strglob()].
*/
SQLITE_API int sqlite3_strlike(const char *zGlob, const char *zStr, unsigned int cEsc);

/*
** CAPI3REF: Error Logging Interface
**
** ^The [sqlite3_log()] interface writes a message into the [error log]
** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()].
** ^If logging is enabled, the zFormat string and subsequent arguments are
** used with [sqlite3_snprintf()] to generate the final output string.
**
** The sqlite3_log() interface is intended for use by extensions such as
** virtual tables, collating functions, and SQL functions.  While there is
** nothing to prevent an application from calling sqlite3_log(), doing so

** a few hundred characters, it will be truncated to the length of the
** buffer.
*/
SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...);

/*
** CAPI3REF: Write-Ahead Log Commit Hook
** METHOD: sqlite3
**
** ^The [sqlite3_wal_hook()] function is used to register a callback that
** is invoked each time data is committed to a database in wal mode.


**
** ^(The callback is invoked by SQLite after the commit has taken place and 
** the associated write-lock on the database released)^, so the implementation 
** may read, write or [checkpoint] the database as required.
**
** ^The first parameter passed to the callback function when it is invoked
** is a copy of the third parameter passed to sqlite3_wal_hook() when
** registering the callback. ^The second is a copy of the database handle.
** ^The third parameter is the name of the database that was written to -
** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter

** are undefined.
**
** A single database handle may have at most a single write-ahead log callback 
** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any
** previously registered write-ahead log callback. ^Note that the
** [sqlite3_wal_autocheckpoint()] interface and the
** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will
** overwrite any prior [sqlite3_wal_hook()] settings.
*/
SQLITE_API void *sqlite3_wal_hook(
  sqlite3*, 
  int(*)(void *,sqlite3*,const char*,int),
  void*
);

/*
** CAPI3REF: Configure an auto-checkpoint
** METHOD: sqlite3
**
** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around
** [sqlite3_wal_hook()] that causes any database on [database connection] D
** to automatically [checkpoint]
** after committing a transaction if there are N or
** more frames in the [write-ahead log] file.  ^Passing zero or 
** a negative value as the nFrame parameter disables automatic
** checkpoints entirely.
**
** ^The callback registered by this function replaces any existing callback
** registered using [sqlite3_wal_hook()].  ^Likewise, registering a callback
** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism
** configured by this function.
**
** ^The [wal_autocheckpoint pragma] can be used to invoke this interface
** from SQL.
**
** ^Checkpoints initiated by this mechanism are
** [sqlite3_wal_checkpoint_v2|PASSIVE].
**
** ^Every new [database connection] defaults to having the auto-checkpoint
** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT]
** pages.  The use of this interface
** is only necessary if the default setting is found to be suboptimal
** for a particular application.
*/
SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int N);

/*
** CAPI3REF: Checkpoint a database
** METHOD: sqlite3
**
** ^(The sqlite3_wal_checkpoint(D,X) is equivalent to

** [sqlite3_wal_checkpoint_v2](D,X,[SQLITE_CHECKPOINT_PASSIVE],0,0).)^


**
** In brief, sqlite3_wal_checkpoint(D,X) causes the content in the 
** [write-ahead log] for database X on [database connection] D to be
** transferred into the database file and for the write-ahead log to
** be reset.  See the [checkpointing] documentation for addition
** information.

**
** This interface used to be the only way to cause a checkpoint to
** occur.  But then the newer and more powerful [sqlite3_wal_checkpoint_v2()]
** interface was added.  This interface is retained for backwards
** compatibility and as a convenience for applications that need to manually
** start a callback but which do not need the full power (and corresponding
** complication) of [sqlite3_wal_checkpoint_v2()].
*/
SQLITE_API int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb);

/*
** CAPI3REF: Checkpoint a database
** METHOD: sqlite3
**
** ^(The sqlite3_wal_checkpoint_v2(D,X,M,L,C) interface runs a checkpoint
** operation on database X of [database connection] D in mode M.  Status
** information is written back into integers pointed to by L and C.)^
** ^(The M parameter must be a valid [checkpoint mode]:)^
**
** <dl>
** <dt>SQLITE_CHECKPOINT_PASSIVE<dd>
**   ^Checkpoint as many frames as possible without waiting for any database 
**   readers or writers to finish, then sync the database file if all frames 
**   in the log were checkpointed. ^The [busy-handler callback]
**   is never invoked in the SQLITE_CHECKPOINT_PASSIVE mode.  
**   ^On the other hand, passive mode might leave the checkpoint unfinished
**   if there are concurrent readers or writers.
**
** <dt>SQLITE_CHECKPOINT_FULL<dd>
**   ^This mode blocks (it invokes the
**   [sqlite3_busy_handler|busy-handler callback]) until there is no
**   database writer and all readers are reading from the most recent database
**   snapshot. ^It then checkpoints all frames in the log file and syncs the
**   database file. ^This mode blocks new database writers while it is pending,
**   but new database readers are allowed to continue unimpeded.
**
** <dt>SQLITE_CHECKPOINT_RESTART<dd>
**   ^This mode works the same way as SQLITE_CHECKPOINT_FULL with the addition
**   that after checkpointing the log file it blocks (calls the 
**   [busy-handler callback])
**   until all readers are reading from the database file only. ^This ensures 
**   that the next writer will restart the log file from the beginning.
**   ^Like SQLITE_CHECKPOINT_FULL, this mode blocks new
**   database writer attempts while it is pending, but does not impede readers.
**
** <dt>SQLITE_CHECKPOINT_TRUNCATE<dd>
**   ^This mode works the same way as SQLITE_CHECKPOINT_RESTART with the
**   addition that it also truncates the log file to zero bytes just prior
**   to a successful return.
** </dl>
**
** ^If pnLog is not NULL, then *pnLog is set to the total number of frames in
** the log file or to -1 if the checkpoint could not run because
** of an error or because the database is not in [WAL mode]. ^If pnCkpt is not
** NULL,then *pnCkpt is set to the total number of checkpointed frames in the
** log file (including any that were already checkpointed before the function
** was called) or to -1 if the checkpoint could not run due to an error or
** because the database is not in WAL mode. ^Note that upon successful
** completion of an SQLITE_CHECKPOINT_TRUNCATE, the log file will have been


** truncated to zero bytes and so both *pnLog and *pnCkpt will be set to zero.
**
** ^All calls obtain an exclusive "checkpoint" lock on the database file. ^If
** any other process is running a checkpoint operation at the same time, the 
** lock cannot be obtained and SQLITE_BUSY is returned. ^Even if there is a 
** busy-handler configured, it will not be invoked in this case.
**
** ^The SQLITE_CHECKPOINT_FULL, RESTART and TRUNCATE modes also obtain the 
** exclusive "writer" lock on the database file. ^If the writer lock cannot be
** obtained immediately, and a busy-handler is configured, it is invoked and
** the writer lock retried until either the busy-handler returns 0 or the lock
** is successfully obtained. ^The busy-handler is also invoked while waiting for
** database readers as described above. ^If the busy-handler returns 0 before
** the writer lock is obtained or while waiting for database readers, the
** checkpoint operation proceeds from that point in the same way as 
** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible 
** without blocking any further. ^SQLITE_BUSY is returned in this case.
**
** ^If parameter zDb is NULL or points to a zero length string, then the
** specified operation is attempted on all WAL databases [attached] to 
** [database connection] db.  In this case the
** values written to output parameters *pnLog and *pnCkpt are undefined. ^If 
** an SQLITE_BUSY error is encountered when processing one or more of the 
** attached WAL databases, the operation is still attempted on any remaining 
** attached databases and SQLITE_BUSY is returned at the end. ^If any other 
** error occurs while processing an attached database, processing is abandoned 
** and the error code is returned to the caller immediately. ^If no error 
** (SQLITE_BUSY or otherwise) is encountered while processing the attached 
** databases, SQLITE_OK is returned.
**
** ^If database zDb is the name of an attached database that is not in WAL
** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. ^If
** zDb is not NULL (or a zero length string) and is not the name of any
** attached database, SQLITE_ERROR is returned to the caller.
**
** ^Unless it returns SQLITE_MISUSE,
** the sqlite3_wal_checkpoint_v2() interface
** sets the error information that is queried by
** [sqlite3_errcode()] and [sqlite3_errmsg()].
**
** ^The [PRAGMA wal_checkpoint] command can be used to invoke this interface
** from SQL.
*/
SQLITE_API int sqlite3_wal_checkpoint_v2(
  sqlite3 *db,                    /* Database handle */
  const char *zDb,                /* Name of attached database (or NULL) */
  int eMode,                      /* SQLITE_CHECKPOINT_* value */
  int *pnLog,                     /* OUT: Size of WAL log in frames */
  int *pnCkpt                     /* OUT: Total number of frames checkpointed */
);

/*
** CAPI3REF: Checkpoint Mode Values
** KEYWORDS: {checkpoint mode}
**
** These constants define all valid values for the "checkpoint mode" passed
** as the third parameter to the [sqlite3_wal_checkpoint_v2()] interface.
** See the [sqlite3_wal_checkpoint_v2()] documentation for details on the
** meaning of each of these checkpoint modes.
*/
#define SQLITE_CHECKPOINT_PASSIVE  0  /* Do as much as possible w/o blocking */
#define SQLITE_CHECKPOINT_FULL     1  /* Wait for writers, then checkpoint */
#define SQLITE_CHECKPOINT_RESTART  2  /* Like FULL but wait for for readers */
#define SQLITE_CHECKPOINT_TRUNCATE 3  /* Like RESTART but also truncate WAL */

/*
** CAPI3REF: Virtual Table Interface Configuration
**
** This function may be called by either the [xConnect] or [xCreate] method
** of a [virtual table] implementation to configure
** various facets of the virtual table interface.

** of the SQL statement that triggered the call to the [xUpdate] method of the
** [virtual table].
*/
SQLITE_API int sqlite3_vtab_on_conflict(sqlite3 *);

/*
** CAPI3REF: Conflict resolution modes
** KEYWORDS: {conflict resolution mode}
**
** These constants are returned by [sqlite3_vtab_on_conflict()] to
** inform a [virtual table] implementation what the [ON CONFLICT] mode
** is for the SQL statement being evaluated.
**
** Note that the [SQLITE_IGNORE] constant is also used as a potential
** return value from the [sqlite3_set_authorizer()] callback and that
** [SQLITE_ABORT] is also a [result code].
*/
#define SQLITE_ROLLBACK 1
/* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */
#define SQLITE_FAIL     3
/* #define SQLITE_ABORT 4  // Also an error code */
#define SQLITE_REPLACE  5

/*
** CAPI3REF: Prepared Statement Scan Status Opcodes
** KEYWORDS: {scanstatus options}
**
** The following constants can be used for the T parameter to the
** [sqlite3_stmt_scanstatus(S,X,T,V)] interface.  Each constant designates a
** different metric for sqlite3_stmt_scanstatus() to return.
**
** When the value returned to V is a string, space to hold that string is
** managed by the prepared statement S and will be automatically freed when
** S is finalized.
**
** <dl>
** [[SQLITE_SCANSTAT_NLOOP]] <dt>SQLITE_SCANSTAT_NLOOP</dt>
** <dd>^The [sqlite3_int64] variable pointed to by the T parameter will be
** set to the total number of times that the X-th loop has run.</dd>
**
** [[SQLITE_SCANSTAT_NVISIT]] <dt>SQLITE_SCANSTAT_NVISIT</dt>
** <dd>^The [sqlite3_int64] variable pointed to by the T parameter will be set
** to the total number of rows examined by all iterations of the X-th loop.</dd>
**
** [[SQLITE_SCANSTAT_EST]] <dt>SQLITE_SCANSTAT_EST</dt>
** <dd>^The "double" variable pointed to by the T parameter will be set to the
** query planner's estimate for the average number of rows output from each
** iteration of the X-th loop.  If the query planner's estimates was accurate,
** then this value will approximate the quotient NVISIT/NLOOP and the
** product of this value for all prior loops with the same SELECTID will
** be the NLOOP value for the current loop.
**
** [[SQLITE_SCANSTAT_NAME]] <dt>SQLITE_SCANSTAT_NAME</dt>
** <dd>^The "const char *" variable pointed to by the T parameter will be set
** to a zero-terminated UTF-8 string containing the name of the index or table
** used for the X-th loop.
**
** [[SQLITE_SCANSTAT_EXPLAIN]] <dt>SQLITE_SCANSTAT_EXPLAIN</dt>
** <dd>^The "const char *" variable pointed to by the T parameter will be set
** to a zero-terminated UTF-8 string containing the [EXPLAIN QUERY PLAN]
** description for the X-th loop.
**
** [[SQLITE_SCANSTAT_SELECTID]] <dt>SQLITE_SCANSTAT_SELECT</dt>
** <dd>^The "int" variable pointed to by the T parameter will be set to the
** "select-id" for the X-th loop.  The select-id identifies which query or
** subquery the loop is part of.  The main query has a select-id of zero.
** The select-id is the same value as is output in the first column
** of an [EXPLAIN QUERY PLAN] query.
** </dl>
*/
#define SQLITE_SCANSTAT_NLOOP    0
#define SQLITE_SCANSTAT_NVISIT   1
#define SQLITE_SCANSTAT_EST      2
#define SQLITE_SCANSTAT_NAME     3
#define SQLITE_SCANSTAT_EXPLAIN  4
#define SQLITE_SCANSTAT_SELECTID 5

/*
** CAPI3REF: Prepared Statement Scan Status
** METHOD: sqlite3_stmt
**
** This interface returns information about the predicted and measured
** performance for pStmt.  Advanced applications can use this
** interface to compare the predicted and the measured performance and
** issue warnings and/or rerun [ANALYZE] if discrepancies are found.
**
** Since this interface is expected to be rarely used, it is only
** available if SQLite is compiled using the [SQLITE_ENABLE_STMT_SCANSTATUS]
** compile-time option.
**
** The "iScanStatusOp" parameter determines which status information to return.
** The "iScanStatusOp" must be one of the [scanstatus options] or the behavior
** of this interface is undefined.
** ^The requested measurement is written into a variable pointed to by
** the "pOut" parameter.
** Parameter "idx" identifies the specific loop to retrieve statistics for.
** Loops are numbered starting from zero. ^If idx is out of range - less than
** zero or greater than or equal to the total number of loops used to implement
** the statement - a non-zero value is returned and the variable that pOut
** points to is unchanged.
**
** ^Statistics might not be available for all loops in all statements. ^In cases
** where there exist loops with no available statistics, this function behaves
** as if the loop did not exist - it returns non-zero and leave the variable
** that pOut points to unchanged.
**
** See also: [sqlite3_stmt_scanstatus_reset()]
*/
SQLITE_API int sqlite3_stmt_scanstatus(
  sqlite3_stmt *pStmt,      /* Prepared statement for which info desired */
  int idx,                  /* Index of loop to report on */
  int iScanStatusOp,        /* Information desired.  SQLITE_SCANSTAT_* */
  void *pOut                /* Result written here */
);     

/*
** CAPI3REF: Zero Scan-Status Counters
** METHOD: sqlite3_stmt
**
** ^Zero all [sqlite3_stmt_scanstatus()] related event counters.
**
** This API is only available if the library is built with pre-processor
** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined.
*/
SQLITE_API void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*);

/*
** CAPI3REF: Flush caches to disk mid-transaction
**
** ^If a write-transaction is open on [database connection] D when the
** [sqlite3_db_cacheflush(D)] interface invoked, any dirty
** pages in the pager-cache that are not currently in use are written out 
** to disk. A dirty page may be in use if a database cursor created by an
** active SQL statement is reading from it, or if it is page 1 of a database
** file (page 1 is always "in use").  ^The [sqlite3_db_cacheflush(D)]
** interface flushes caches for all schemas - "main", "temp", and
** any [attached] databases.
**
** ^If this function needs to obtain extra database locks before dirty pages 
** can be flushed to disk, it does so. ^If those locks cannot be obtained 
** immediately and there is a busy-handler callback configured, it is invoked
** in the usual manner. ^If the required lock still cannot be obtained, then
** the database is skipped and an attempt made to flush any dirty pages
** belonging to the next (if any) database. ^If any databases are skipped
** because locks cannot be obtained, but no other error occurs, this
** function returns SQLITE_BUSY.
**
** ^If any other error occurs while flushing dirty pages to disk (for
** example an IO error or out-of-memory condition), then processing is
** abandoned and an SQLite [error code] is returned to the caller immediately.
**
** ^Otherwise, if no error occurs, [sqlite3_db_cacheflush()] returns SQLITE_OK.
**
** ^This function does not set the database handle error code or message
** returned by the [sqlite3_errcode()] and [sqlite3_errmsg()] functions.
*/
SQLITE_API int sqlite3_db_cacheflush(sqlite3*);

/*
** CAPI3REF: The pre-update hook.
**
** ^These interfaces are only available if SQLite is compiled using the
** [SQLITE_ENABLE_PREUPDATE_HOOK] compile-time option.
**
** ^The [sqlite3_preupdate_hook()] interface registers a callback function
** that is invoked prior to each [INSERT], [UPDATE], and [DELETE] operation
** on a [rowid table].
** ^At most one preupdate hook may be registered at a time on a single
** [database connection]; each call to [sqlite3_preupdate_hook()] overrides
** the previous setting.
** ^The preupdate hook is disabled by invoking [sqlite3_preupdate_hook()]
** with a NULL pointer as the second parameter.
** ^The third parameter to [sqlite3_preupdate_hook()] is passed through as
** the first parameter to callbacks.
**
** ^The preupdate hook only fires for changes to [rowid tables]; the preupdate
** hook is not invoked for changes to [virtual tables] or [WITHOUT ROWID]
** tables.
**
** ^The second parameter to the preupdate callback is a pointer to
** the [database connection] that registered the preupdate hook.
** ^The third parameter to the preupdate callback is one of the constants
** [SQLITE_INSERT], [SQLITE_DELETE], or [SQLITE_UPDATE] to identify the
** kind of update operation that is about to occur.
** ^(The fourth parameter to the preupdate callback is the name of the
** database within the database connection that is being modified.  This
** will be "main" for the main database or "temp" for TEMP tables or 
** the name given after the AS keyword in the [ATTACH] statement for attached
** databases.)^
** ^The fifth parameter to the preupdate callback is the name of the
** table that is being modified.
** ^The sixth parameter to the preupdate callback is the initial [rowid] of the
** row being changes for SQLITE_UPDATE and SQLITE_DELETE changes and is
** undefined for SQLITE_INSERT changes.
** ^The seventh parameter to the preupdate callback is the final [rowid] of
** the row being changed for SQLITE_UPDATE and SQLITE_INSERT changes and is
** undefined for SQLITE_DELETE changes.
**
** The [sqlite3_preupdate_old()], [sqlite3_preupdate_new()],
** [sqlite3_preupdate_count()], and [sqlite3_preupdate_depth()] interfaces
** provide additional information about a preupdate event. These routines
** may only be called from within a preupdate callback.  Invoking any of
** these routines from outside of a preupdate callback or with a
** [database connection] pointer that is different from the one supplied
** to the preupdate callback results in undefined and probably undesirable
** behavior.
**
** ^The [sqlite3_preupdate_count(D)] interface returns the number of columns
** in the row that is being inserted, updated, or deleted.
**
** ^The [sqlite3_preupdate_old(D,N,P)] interface writes into P a pointer to
** a [protected sqlite3_value] that contains the value of the Nth column of
** the table row before it is updated.  The N parameter must be between 0
** and one less than the number of columns or the behavior will be
** undefined. This must only be used within SQLITE_UPDATE and SQLITE_DELETE
** preupdate callbacks; if it is used by an SQLITE_INSERT callback then the
** behavior is undefined.  The [sqlite3_value] that P points to
** will be destroyed when the preupdate callback returns.
**
** ^The [sqlite3_preupdate_new(D,N,P)] interface writes into P a pointer to
** a [protected sqlite3_value] that contains the value of the Nth column of
** the table row after it is updated.  The N parameter must be between 0
** and one less than the number of columns or the behavior will be
** undefined. This must only be used within SQLITE_INSERT and SQLITE_UPDATE
** preupdate callbacks; if it is used by an SQLITE_DELETE callback then the
** behavior is undefined.  The [sqlite3_value] that P points to
** will be destroyed when the preupdate callback returns.
**
** ^The [sqlite3_preupdate_depth(D)] interface returns 0 if the preupdate
** callback was invoked as a result of a direct insert, update, or delete
** operation; or 1 for inserts, updates, or deletes invoked by top-level 
** triggers; or 2 for changes resulting from triggers called by top-level
** triggers; and so forth.
**
** See also:  [sqlite3_update_hook()]
*/
SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_preupdate_hook(
  sqlite3 *db,
  void(*xPreUpdate)(
    void *pCtx,                   /* Copy of third arg to preupdate_hook() */
    sqlite3 *db,                  /* Database handle */
    int op,                       /* SQLITE_UPDATE, DELETE or INSERT */
    char const *zDb,              /* Database name */
    char const *zName,            /* Table name */
    sqlite3_int64 iKey1,          /* Rowid of row about to be deleted/updated */
    sqlite3_int64 iKey2           /* New rowid value (for a rowid UPDATE) */
  ),
  void*
);
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_preupdate_old(sqlite3 *, int, sqlite3_value **);
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_preupdate_count(sqlite3 *);
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_preupdate_depth(sqlite3 *);
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_preupdate_new(sqlite3 *, int, sqlite3_value **);

/*
** CAPI3REF: Low-level system error code
**
** ^Attempt to return the underlying operating system error code or error
** number that caused the most recent I/O error or failure to open a file.
** The return value is OS-dependent.  For example, on unix systems, after
** [sqlite3_open_v2()] returns [SQLITE_CANTOPEN], this interface could be
** called to get back the underlying "errno" that caused the problem, such
** as ENOSPC, EAUTH, EISDIR, and so forth.  
*/
SQLITE_API int sqlite3_system_errno(sqlite3*);

/*
** CAPI3REF: Database Snapshot
** KEYWORDS: {snapshot}
** EXPERIMENTAL
**
** An instance of the snapshot object records the state of a [WAL mode]
** database for some specific point in history.
**
** In [WAL mode], multiple [database connections] that are open on the
** same database file can each be reading a different historical version
** of the database file.  When a [database connection] begins a read
** transaction, that connection sees an unchanging copy of the database
** as it existed for the point in time when the transaction first started.
** Subsequent changes to the database from other connections are not seen
** by the reader until a new read transaction is started.
**
** The sqlite3_snapshot object records state information about an historical
** version of the database file so that it is possible to later open a new read
** transaction that sees that historical version of the database rather than
** the most recent version.
**
** The constructor for this object is [sqlite3_snapshot_get()].  The
** [sqlite3_snapshot_open()] method causes a fresh read transaction to refer
** to an historical snapshot (if possible).  The destructor for 
** sqlite3_snapshot objects is [sqlite3_snapshot_free()].
*/
typedef struct sqlite3_snapshot sqlite3_snapshot;

/*
** CAPI3REF: Record A Database Snapshot
** EXPERIMENTAL
**
** ^The [sqlite3_snapshot_get(D,S,P)] interface attempts to make a
** new [sqlite3_snapshot] object that records the current state of
** schema S in database connection D.  ^On success, the
** [sqlite3_snapshot_get(D,S,P)] interface writes a pointer to the newly
** created [sqlite3_snapshot] object into *P and returns SQLITE_OK.
** ^If schema S of [database connection] D is not a [WAL mode] database
** that is in a read transaction, then [sqlite3_snapshot_get(D,S,P)]
** leaves the *P value unchanged and returns an appropriate [error code].
**
** The [sqlite3_snapshot] object returned from a successful call to
** [sqlite3_snapshot_get()] must be freed using [sqlite3_snapshot_free()]
** to avoid a memory leak.
**
** The [sqlite3_snapshot_get()] interface is only available when the
** SQLITE_ENABLE_SNAPSHOT compile-time option is used.
*/
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_get(
  sqlite3 *db,
  const char *zSchema,
  sqlite3_snapshot **ppSnapshot
);

/*
** CAPI3REF: Start a read transaction on an historical snapshot
** EXPERIMENTAL
**
** ^The [sqlite3_snapshot_open(D,S,P)] interface starts a
** read transaction for schema S of
** [database connection] D such that the read transaction
** refers to historical [snapshot] P, rather than the most
** recent change to the database.
** ^The [sqlite3_snapshot_open()] interface returns SQLITE_OK on success
** or an appropriate [error code] if it fails.
**
** ^In order to succeed, a call to [sqlite3_snapshot_open(D,S,P)] must be
** the first operation following the [BEGIN] that takes the schema S
** out of [autocommit mode].
** ^In other words, schema S must not currently be in
** a transaction for [sqlite3_snapshot_open(D,S,P)] to work, but the
** database connection D must be out of [autocommit mode].
** ^A [snapshot] will fail to open if it has been overwritten by a
** [checkpoint].
** ^(A call to [sqlite3_snapshot_open(D,S,P)] will fail if the
** database connection D does not know that the database file for
** schema S is in [WAL mode].  A database connection might not know
** that the database file is in [WAL mode] if there has been no prior
** I/O on that database connection, or if the database entered [WAL mode] 
** after the most recent I/O on the database connection.)^
** (Hint: Run "[PRAGMA application_id]" against a newly opened
** database connection in order to make it ready to use snapshots.)
**
** The [sqlite3_snapshot_open()] interface is only available when the
** SQLITE_ENABLE_SNAPSHOT compile-time option is used.
*/
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_open(
  sqlite3 *db,
  const char *zSchema,
  sqlite3_snapshot *pSnapshot
);

/*
** CAPI3REF: Destroy a snapshot
** EXPERIMENTAL
**
** ^The [sqlite3_snapshot_free(P)] interface destroys [sqlite3_snapshot] P.
** The application must eventually free every [sqlite3_snapshot] object
** using this routine to avoid a memory leak.
**
** The [sqlite3_snapshot_free()] interface is only available when the
** SQLITE_ENABLE_SNAPSHOT compile-time option is used.
*/
SQLITE_API SQLITE_EXPERIMENTAL void sqlite3_snapshot_free(sqlite3_snapshot*);

/*
** CAPI3REF: Compare the ages of two snapshot handles.
** EXPERIMENTAL
**
** The sqlite3_snapshot_cmp(P1, P2) interface is used to compare the ages
** of two valid snapshot handles. 
**
** If the two snapshot handles are not associated with the same database 
** file, the result of the comparison is undefined. 
**
** Additionally, the result of the comparison is only valid if both of the
** snapshot handles were obtained by calling sqlite3_snapshot_get() since the
** last time the wal file was deleted. The wal file is deleted when the
** database is changed back to rollback mode or when the number of database
** clients drops to zero. If either snapshot handle was obtained before the 
** wal file was last deleted, the value returned by this function 
** is undefined.
**
** Otherwise, this API returns a negative value if P1 refers to an older
** snapshot than P2, zero if the two handles refer to the same database
** snapshot, and a positive value if P1 is a newer snapshot than P2.
*/
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_cmp(
  sqlite3_snapshot *p1,
  sqlite3_snapshot *p2
);

/*
** Undo the hack that converts floating point types to integer for
** builds on processors without floating point support.
*/
#ifdef SQLITE_OMIT_FLOATING_POINT
# undef double
#endif

#ifdef __cplusplus
}  /* End of the 'extern "C"' block */
#endif
#endif /* SQLITE3_H */

/******** Begin file sqlite3rtree.h *********/
/*
** 2010 August 30
**
** 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.

#ifdef __cplusplus
extern "C" {
#endif

typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry;
typedef struct sqlite3_rtree_query_info sqlite3_rtree_query_info;

/* The double-precision datatype used by RTree depends on the
** SQLITE_RTREE_INT_ONLY compile-time option.
*/
#ifdef SQLITE_RTREE_INT_ONLY
  typedef sqlite3_int64 sqlite3_rtree_dbl;
#else
  typedef double sqlite3_rtree_dbl;
#endif

/*
** Register a geometry callback named zGeom that can be used as part of an
** R-Tree geometry query as follows:
**
**   SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...)
*/
SQLITE_API int sqlite3_rtree_geometry_callback(
  sqlite3 *db,
  const char *zGeom,



  int (*xGeom)(sqlite3_rtree_geometry*, int, sqlite3_rtree_dbl*,int*),

  void *pContext
);


/*
** A pointer to a structure of the following type is passed as the first
** argument to callbacks registered using rtree_geometry_callback().
*/
struct sqlite3_rtree_geometry {
  void *pContext;                 /* Copy of pContext passed to s_r_g_c() */
  int nParam;                     /* Size of array aParam[] */
  sqlite3_rtree_dbl *aParam;      /* Parameters passed to SQL geom function */
  void *pUser;                    /* Callback implementation user data */
  void (*xDelUser)(void *);       /* Called by SQLite to clean up pUser */
};

/*
** Register a 2nd-generation geometry callback named zScore that can be 
** used as part of an R-Tree geometry query as follows:
**
**   SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zQueryFunc(... params ...)
*/
SQLITE_API int sqlite3_rtree_query_callback(
  sqlite3 *db,
  const char *zQueryFunc,
  int (*xQueryFunc)(sqlite3_rtree_query_info*),
  void *pContext,
  void (*xDestructor)(void*)
);


/*
** A pointer to a structure of the following type is passed as the 
** argument to scored geometry callback registered using
** sqlite3_rtree_query_callback().
**
** Note that the first 5 fields of this structure are identical to
** sqlite3_rtree_geometry.  This structure is a subclass of
** sqlite3_rtree_geometry.
*/
struct sqlite3_rtree_query_info {
  void *pContext;                   /* pContext from when function registered */
  int nParam;                       /* Number of function parameters */
  sqlite3_rtree_dbl *aParam;        /* value of function parameters */
  void *pUser;                      /* callback can use this, if desired */
  void (*xDelUser)(void*);          /* function to free pUser */
  sqlite3_rtree_dbl *aCoord;        /* Coordinates of node or entry to check */
  unsigned int *anQueue;            /* Number of pending entries in the queue */
  int nCoord;                       /* Number of coordinates */
  int iLevel;                       /* Level of current node or entry */
  int mxLevel;                      /* The largest iLevel value in the tree */
  sqlite3_int64 iRowid;             /* Rowid for current entry */
  sqlite3_rtree_dbl rParentScore;   /* Score of parent node */
  int eParentWithin;                /* Visibility of parent node */
  int eWithin;                      /* OUT: Visiblity */
  sqlite3_rtree_dbl rScore;         /* OUT: Write the score here */
  /* The following fields are only available in 3.8.11 and later */
  sqlite3_value **apSqlParam;       /* Original SQL values of parameters */
};

/*
** Allowed values for sqlite3_rtree_query.eWithin and .eParentWithin.
*/
#define NOT_WITHIN       0   /* Object completely outside of query region */
#define PARTLY_WITHIN    1   /* Object partially overlaps query region */
#define FULLY_WITHIN     2   /* Object fully contained within query region */


#ifdef __cplusplus
}  /* end of the 'extern "C"' block */
#endif

#endif  /* ifndef _SQLITE3RTREE_H_ */

/******** End of sqlite3rtree.h *********/
/******** Begin file sqlite3session.h *********/

#if !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION)
#define __SQLITESESSION_H_ 1

/*
** Make sure we can call this stuff from C++.
*/
#ifdef __cplusplus
extern "C" {
#endif


/*
** CAPI3REF: Session Object Handle
*/
typedef struct sqlite3_session sqlite3_session;

/*
** CAPI3REF: Changeset Iterator Handle
*/
typedef struct sqlite3_changeset_iter sqlite3_changeset_iter;

/*
** CAPI3REF: Create A New Session Object
**
** Create a new session object attached to database handle db. If successful,
** a pointer to the new object is written to *ppSession and SQLITE_OK is
** returned. If an error occurs, *ppSession is set to NULL and an SQLite
** error code (e.g. SQLITE_NOMEM) is returned.
**
** It is possible to create multiple session objects attached to a single
** database handle.
**
** Session objects created using this function should be deleted using the
** [sqlite3session_delete()] function before the database handle that they
** are attached to is itself closed. If the database handle is closed before
** the session object is deleted, then the results of calling any session
** module function, including [sqlite3session_delete()] on the session object
** are undefined.
**
** Because the session module uses the [sqlite3_preupdate_hook()] API, it
** is not possible for an application to register a pre-update hook on a
** database handle that has one or more session objects attached. Nor is
** it possible to create a session object attached to a database handle for
** which a pre-update hook is already defined. The results of attempting 
** either of these things are undefined.
**
** The session object will be used to create changesets for tables in
** database zDb, where zDb is either "main", or "temp", or the name of an
** attached database. It is not an error if database zDb is not attached
** to the database when the session object is created.
*/
int sqlite3session_create(
  sqlite3 *db,                    /* Database handle */
  const char *zDb,                /* Name of db (e.g. "main") */
  sqlite3_session **ppSession     /* OUT: New session object */
);

/*
** CAPI3REF: Delete A Session Object
**
** Delete a session object previously allocated using 
** [sqlite3session_create()]. Once a session object has been deleted, the
** results of attempting to use pSession with any other session module
** function are undefined.
**
** Session objects must be deleted before the database handle to which they
** are attached is closed. Refer to the documentation for 
** [sqlite3session_create()] for details.
*/
void sqlite3session_delete(sqlite3_session *pSession);


/*
** CAPI3REF: Enable Or Disable A Session Object
**
** Enable or disable the recording of changes by a session object. When
** enabled, a session object records changes made to the database. When
** disabled - it does not. A newly created session object is enabled.
** Refer to the documentation for [sqlite3session_changeset()] for further
** details regarding how enabling and disabling a session object affects
** the eventual changesets.
**
** Passing zero to this function disables the session. Passing a value
** greater than zero enables it. Passing a value less than zero is a 
** no-op, and may be used to query the current state of the session.
**
** The return value indicates the final state of the session object: 0 if 
** the session is disabled, or 1 if it is enabled.
*/
int sqlite3session_enable(sqlite3_session *pSession, int bEnable);

/*
** CAPI3REF: Set Or Clear the Indirect Change Flag
**
** Each change recorded by a session object is marked as either direct or
** indirect. A change is marked as indirect if either:
**
** <ul>
**   <li> The session object "indirect" flag is set when the change is
**        made, or
**   <li> The change is made by an SQL trigger or foreign key action 
**        instead of directly as a result of a users SQL statement.
** </ul>
**
** If a single row is affected by more than one operation within a session,
** then the change is considered indirect if all operations meet the criteria
** for an indirect change above, or direct otherwise.
**
** This function is used to set, clear or query the session object indirect
** flag.  If the second argument passed to this function is zero, then the
** indirect flag is cleared. If it is greater than zero, the indirect flag
** is set. Passing a value less than zero does not modify the current value
** of the indirect flag, and may be used to query the current state of the 
** indirect flag for the specified session object.
**
** The return value indicates the final state of the indirect flag: 0 if 
** it is clear, or 1 if it is set.
*/
int sqlite3session_indirect(sqlite3_session *pSession, int bIndirect);

/*
** CAPI3REF: Attach A Table To A Session Object
**
** If argument zTab is not NULL, then it is the name of a table to attach
** to the session object passed as the first argument. All subsequent changes 
** made to the table while the session object is enabled will be recorded. See 
** documentation for [sqlite3session_changeset()] for further details.
**
** Or, if argument zTab is NULL, then changes are recorded for all tables
** in the database. If additional tables are added to the database (by 
** executing "CREATE TABLE" statements) after this call is made, changes for 
** the new tables are also recorded.
**
** Changes can only be recorded for tables that have a PRIMARY KEY explicitly
** defined as part of their CREATE TABLE statement. It does not matter if the 
** PRIMARY KEY is an "INTEGER PRIMARY KEY" (rowid alias) or not. The PRIMARY
** KEY may consist of a single column, or may be a composite key.
** 
** It is not an error if the named table does not exist in the database. Nor
** is it an error if the named table does not have a PRIMARY KEY. However,
** no changes will be recorded in either of these scenarios.
**
** Changes are not recorded for individual rows that have NULL values stored
** in one or more of their PRIMARY KEY columns.
**
** SQLITE_OK is returned if the call completes without error. Or, if an error 
** occurs, an SQLite error code (e.g. SQLITE_NOMEM) is returned.
*/
int sqlite3session_attach(
  sqlite3_session *pSession,      /* Session object */
  const char *zTab                /* Table name */
);

/*
** CAPI3REF: Set a table filter on a Session Object.
**
** The second argument (xFilter) is the "filter callback". For changes to rows 
** in tables that are not attached to the Session object, the filter is called
** to determine whether changes to the table's rows should be tracked or not. 
** If xFilter returns 0, changes is not tracked. Note that once a table is 
** attached, xFilter will not be called again.
*/
void sqlite3session_table_filter(
  sqlite3_session *pSession,      /* Session object */
  int(*xFilter)(
    void *pCtx,                   /* Copy of third arg to _filter_table() */
    const char *zTab              /* Table name */
  ),
  void *pCtx                      /* First argument passed to xFilter */
);

/*
** CAPI3REF: Generate A Changeset From A Session Object
**
** Obtain a changeset containing changes to the tables attached to the 
** session object passed as the first argument. If successful, 
** set *ppChangeset to point to a buffer containing the changeset 
** and *pnChangeset to the size of the changeset in bytes before returning
** SQLITE_OK. If an error occurs, set both *ppChangeset and *pnChangeset to
** zero and return an SQLite error code.
**
** A changeset consists of zero or more INSERT, UPDATE and/or DELETE changes,
** each representing a change to a single row of an attached table. An INSERT
** change contains the values of each field of a new database row. A DELETE
** contains the original values of each field of a deleted database row. An
** UPDATE change contains the original values of each field of an updated
** database row along with the updated values for each updated non-primary-key
** column. It is not possible for an UPDATE change to represent a change that
** modifies the values of primary key columns. If such a change is made, it
** is represented in a changeset as a DELETE followed by an INSERT.
**
** Changes are not recorded for rows that have NULL values stored in one or 
** more of their PRIMARY KEY columns. If such a row is inserted or deleted,
** no corresponding change is present in the changesets returned by this
** function. If an existing row with one or more NULL values stored in
** PRIMARY KEY columns is updated so that all PRIMARY KEY columns are non-NULL,
** only an INSERT is appears in the changeset. Similarly, if an existing row
** with non-NULL PRIMARY KEY values is updated so that one or more of its
** PRIMARY KEY columns are set to NULL, the resulting changeset contains a
** DELETE change only.
**
** The contents of a changeset may be traversed using an iterator created
** using the [sqlite3changeset_start()] API. A changeset may be applied to
** a database with a compatible schema using the [sqlite3changeset_apply()]
** API.
**
** Within a changeset generated by this function, all changes related to a
** single table are grouped together. In other words, when iterating through
** a changeset or when applying a changeset to a database, all changes related
** to a single table are processed before moving on to the next table. Tables
** are sorted in the same order in which they were attached (or auto-attached)
** to the sqlite3_session object. The order in which the changes related to
** a single table are stored is undefined.
**
** Following a successful call to this function, it is the responsibility of
** the caller to eventually free the buffer that *ppChangeset points to using
** [sqlite3_free()].
**
** <h3>Changeset Generation</h3>
**
** Once a table has been attached to a session object, the session object
** records the primary key values of all new rows inserted into the table.
** It also records the original primary key and other column values of any
** deleted or updated rows. For each unique primary key value, data is only
** recorded once - the first time a row with said primary key is inserted,
** updated or deleted in the lifetime of the session.
**
** There is one exception to the previous paragraph: when a row is inserted,
** updated or deleted, if one or more of its primary key columns contain a
** NULL value, no record of the change is made.
**
** The session object therefore accumulates two types of records - those
** that consist of primary key values only (created when the user inserts
** a new record) and those that consist of the primary key values and the
** original values of other table columns (created when the users deletes
** or updates a record).
**
** When this function is called, the requested changeset is created using
** both the accumulated records and the current contents of the database
** file. Specifically:
**
** <ul>
**   <li> For each record generated by an insert, the database is queried
**        for a row with a matching primary key. If one is found, an INSERT
**        change is added to the changeset. If no such row is found, no change 
**        is added to the changeset.
**
**   <li> For each record generated by an update or delete, the database is 
**        queried for a row with a matching primary key. If such a row is
**        found and one or more of the non-primary key fields have been
**        modified from their original values, an UPDATE change is added to 
**        the changeset. Or, if no such row is found in the table, a DELETE 
**        change is added to the changeset. If there is a row with a matching
**        primary key in the database, but all fields contain their original
**        values, no change is added to the changeset.
** </ul>
**
** This means, amongst other things, that if a row is inserted and then later
** deleted while a session object is active, neither the insert nor the delete
** will be present in the changeset. Or if a row is deleted and then later a 
** row with the same primary key values inserted while a session object is
** active, the resulting changeset will contain an UPDATE change instead of
** a DELETE and an INSERT.
**
** When a session object is disabled (see the [sqlite3session_enable()] API),
** it does not accumulate records when rows are inserted, updated or deleted.
** This may appear to have some counter-intuitive effects if a single row
** is written to more than once during a session. For example, if a row
** is inserted while a session object is enabled, then later deleted while 
** the same session object is disabled, no INSERT record will appear in the
** changeset, even though the delete took place while the session was disabled.
** Or, if one field of a row is updated while a session is disabled, and 
** another field of the same row is updated while the session is enabled, the
** resulting changeset will contain an UPDATE change that updates both fields.
*/
int sqlite3session_changeset(
  sqlite3_session *pSession,      /* Session object */
  int *pnChangeset,               /* OUT: Size of buffer at *ppChangeset */
  void **ppChangeset              /* OUT: Buffer containing changeset */
);

/*
** CAPI3REF: Load The Difference Between Tables Into A Session 
**
** If it is not already attached to the session object passed as the first
** argument, this function attaches table zTbl in the same manner as the
** [sqlite3session_attach()] function. If zTbl does not exist, or if it
** does not have a primary key, this function is a no-op (but does not return
** an error).
**
** Argument zFromDb must be the name of a database ("main", "temp" etc.)
** attached to the same database handle as the session object that contains 
** a table compatible with the table attached to the session by this function.
** A table is considered compatible if it:
**
** <ul>
**   <li> Has the same name,
**   <li> Has the same set of columns declared in the same order, and
**   <li> Has the same PRIMARY KEY definition.
** </ul>
**
** If the tables are not compatible, SQLITE_SCHEMA is returned. If the tables
** are compatible but do not have any PRIMARY KEY columns, it is not an error
** but no changes are added to the session object. As with other session
** APIs, tables without PRIMARY KEYs are simply ignored.
**
** This function adds a set of changes to the session object that could be
** used to update the table in database zFrom (call this the "from-table") 
** so that its content is the same as the table attached to the session 
** object (call this the "to-table"). Specifically:
**
** <ul>
**   <li> For each row (primary key) that exists in the to-table but not in 
**     the from-table, an INSERT record is added to the session object.
**
**   <li> For each row (primary key) that exists in the to-table but not in 
**     the from-table, a DELETE record is added to the session object.
**
**   <li> For each row (primary key) that exists in both tables, but features 
**     different in each, an UPDATE record is added to the session.
** </ul>
**
** To clarify, if this function is called and then a changeset constructed
** using [sqlite3session_changeset()], then after applying that changeset to 
** database zFrom the contents of the two compatible tables would be 
** identical.
**
** It an error if database zFrom does not exist or does not contain the
** required compatible table.
**
** If the operation successful, SQLITE_OK is returned. Otherwise, an SQLite
** error code. In this case, if argument pzErrMsg is not NULL, *pzErrMsg
** may be set to point to a buffer containing an English language error 
** message. It is the responsibility of the caller to free this buffer using
** sqlite3_free().
*/
int sqlite3session_diff(
  sqlite3_session *pSession,
  const char *zFromDb,
  const char *zTbl,
  char **pzErrMsg
);


/*
** CAPI3REF: Generate A Patchset From A Session Object
**
** The differences between a patchset and a changeset are that:
**
** <ul>
**   <li> DELETE records consist of the primary key fields only. The 
**        original values of other fields are omitted.
**   <li> The original values of any modified fields are omitted from 
**        UPDATE records.
** </ul>
**
** A patchset blob may be used with up to date versions of all 
** sqlite3changeset_xxx API functions except for sqlite3changeset_invert(), 
** which returns SQLITE_CORRUPT if it is passed a patchset. Similarly,
** attempting to use a patchset blob with old versions of the
** sqlite3changeset_xxx APIs also provokes an SQLITE_CORRUPT error. 
**
** Because the non-primary key "old.*" fields are omitted, no 
** SQLITE_CHANGESET_DATA conflicts can be detected or reported if a patchset
** is passed to the sqlite3changeset_apply() API. Other conflict types work
** in the same way as for changesets.
**
** Changes within a patchset are ordered in the same way as for changesets
** generated by the sqlite3session_changeset() function (i.e. all changes for
** a single table are grouped together, tables appear in the order in which
** they were attached to the session object).
*/
int sqlite3session_patchset(
  sqlite3_session *pSession,      /* Session object */
  int *pnPatchset,                /* OUT: Size of buffer at *ppChangeset */
  void **ppPatchset               /* OUT: Buffer containing changeset */
);

/*
** CAPI3REF: Test if a changeset has recorded any changes.
**
** Return non-zero if no changes to attached tables have been recorded by 
** the session object passed as the first argument. Otherwise, if one or 
** more changes have been recorded, return zero.
**
** Even if this function returns zero, it is possible that calling
** [sqlite3session_changeset()] on the session handle may still return a
** changeset that contains no changes. This can happen when a row in 
** an attached table is modified and then later on the original values 
** are restored. However, if this function returns non-zero, then it is
** guaranteed that a call to sqlite3session_changeset() will return a 
** changeset containing zero changes.
*/
int sqlite3session_isempty(sqlite3_session *pSession);

/*
** CAPI3REF: Create An Iterator To Traverse A Changeset 
**
** Create an iterator used to iterate through the contents of a changeset.
** If successful, *pp is set to point to the iterator handle and SQLITE_OK
** is returned. Otherwise, if an error occurs, *pp is set to zero and an
** SQLite error code is returned.
**
** The following functions can be used to advance and query a changeset 
** iterator created by this function:
**
** <ul>
**   <li> [sqlite3changeset_next()]
**   <li> [sqlite3changeset_op()]
**   <li> [sqlite3changeset_new()]
**   <li> [sqlite3changeset_old()]
** </ul>
**
** It is the responsibility of the caller to eventually destroy the iterator
** by passing it to [sqlite3changeset_finalize()]. The buffer containing the
** changeset (pChangeset) must remain valid until after the iterator is
** destroyed.
**
** Assuming the changeset blob was created by one of the
** [sqlite3session_changeset()], [sqlite3changeset_concat()] or
** [sqlite3changeset_invert()] functions, all changes within the changeset 
** that apply to a single table are grouped together. This means that when 
** an application iterates through a changeset using an iterator created by 
** this function, all changes that relate to a single table are visited 
** consecutively. There is no chance that the iterator will visit a change 
** the applies to table X, then one for table Y, and then later on visit 
** another change for table X.
*/
int sqlite3changeset_start(
  sqlite3_changeset_iter **pp,    /* OUT: New changeset iterator handle */
  int nChangeset,                 /* Size of changeset blob in bytes */
  void *pChangeset                /* Pointer to blob containing changeset */
);


/*
** CAPI3REF: Advance A Changeset Iterator
**
** This function may only be used with iterators created by function
** [sqlite3changeset_start()]. If it is called on an iterator passed to
** a conflict-handler callback by [sqlite3changeset_apply()], SQLITE_MISUSE
** is returned and the call has no effect.
**
** Immediately after an iterator is created by sqlite3changeset_start(), it
** does not point to any change in the changeset. Assuming the changeset
** is not empty, the first call to this function advances the iterator to
** point to the first change in the changeset. Each subsequent call advances
** the iterator to point to the next change in the changeset (if any). If
** no error occurs and the iterator points to a valid change after a call
** to sqlite3changeset_next() has advanced it, SQLITE_ROW is returned. 
** Otherwise, if all changes in the changeset have already been visited,
** SQLITE_DONE is returned.
**
** If an error occurs, an SQLite error code is returned. Possible error 
** codes include SQLITE_CORRUPT (if the changeset buffer is corrupt) or 
** SQLITE_NOMEM.
*/
int sqlite3changeset_next(sqlite3_changeset_iter *pIter);

/*
** CAPI3REF: Obtain The Current Operation From A Changeset Iterator
**
** The pIter argument passed to this function may either be an iterator
** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
** created by [sqlite3changeset_start()]. In the latter case, the most recent
** call to [sqlite3changeset_next()] must have returned [SQLITE_ROW]. If this
** is not the case, this function returns [SQLITE_MISUSE].
**
** If argument pzTab is not NULL, then *pzTab is set to point to a
** nul-terminated utf-8 encoded string containing the name of the table
** affected by the current change. The buffer remains valid until either
** sqlite3changeset_next() is called on the iterator or until the 
** conflict-handler function returns. If pnCol is not NULL, then *pnCol is 
** set to the number of columns in the table affected by the change. If
** pbIncorrect is not NULL, then *pbIndirect is set to true (1) if the change
** is an indirect change, or false (0) otherwise. See the documentation for
** [sqlite3session_indirect()] for a description of direct and indirect
** changes. Finally, if pOp is not NULL, then *pOp is set to one of 
** [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE], depending on the 
** type of change that the iterator currently points to.
**
** If no error occurs, SQLITE_OK is returned. If an error does occur, an
** SQLite error code is returned. The values of the output variables may not
** be trusted in this case.
*/
int sqlite3changeset_op(
  sqlite3_changeset_iter *pIter,  /* Iterator object */
  const char **pzTab,             /* OUT: Pointer to table name */
  int *pnCol,                     /* OUT: Number of columns in table */
  int *pOp,                       /* OUT: SQLITE_INSERT, DELETE or UPDATE */
  int *pbIndirect                 /* OUT: True for an 'indirect' change */
);

/*
** CAPI3REF: Obtain The Primary Key Definition Of A Table
**
** For each modified table, a changeset includes the following:
**
** <ul>
**   <li> The number of columns in the table, and
**   <li> Which of those columns make up the tables PRIMARY KEY.
** </ul>
**
** This function is used to find which columns comprise the PRIMARY KEY of
** the table modified by the change that iterator pIter currently points to.
** If successful, *pabPK is set to point to an array of nCol entries, where
** nCol is the number of columns in the table. Elements of *pabPK are set to
** 0x01 if the corresponding column is part of the tables primary key, or
** 0x00 if it is not.
**
** If argument pnCol is not NULL, then *pnCol is set to the number of columns
** in the table.
**
** If this function is called when the iterator does not point to a valid
** entry, SQLITE_MISUSE is returned and the output variables zeroed. Otherwise,
** SQLITE_OK is returned and the output variables populated as described
** above.
*/
int sqlite3changeset_pk(
  sqlite3_changeset_iter *pIter,  /* Iterator object */
  unsigned char **pabPK,          /* OUT: Array of boolean - true for PK cols */
  int *pnCol                      /* OUT: Number of entries in output array */
);

/*
** CAPI3REF: Obtain old.* Values From A Changeset Iterator
**
** The pIter argument passed to this function may either be an iterator
** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
** created by [sqlite3changeset_start()]. In the latter case, the most recent
** call to [sqlite3changeset_next()] must have returned SQLITE_ROW. 
** Furthermore, it may only be called if the type of change that the iterator
** currently points to is either [SQLITE_DELETE] or [SQLITE_UPDATE]. Otherwise,
** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL.
**
** Argument iVal must be greater than or equal to 0, and less than the number
** of columns in the table affected by the current change. Otherwise,
** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
**
** If successful, this function sets *ppValue to point to a protected
** sqlite3_value object containing the iVal'th value from the vector of 
** original row values stored as part of the UPDATE or DELETE change and
** returns SQLITE_OK. The name of the function comes from the fact that this 
** is similar to the "old.*" columns available to update or delete triggers.
**
** If some other error occurs (e.g. an OOM condition), an SQLite error code
** is returned and *ppValue is set to NULL.
*/
int sqlite3changeset_old(
  sqlite3_changeset_iter *pIter,  /* Changeset iterator */
  int iVal,                       /* Column number */
  sqlite3_value **ppValue         /* OUT: Old value (or NULL pointer) */
);

/*
** CAPI3REF: Obtain new.* Values From A Changeset Iterator
**
** The pIter argument passed to this function may either be an iterator
** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
** created by [sqlite3changeset_start()]. In the latter case, the most recent
** call to [sqlite3changeset_next()] must have returned SQLITE_ROW. 
** Furthermore, it may only be called if the type of change that the iterator
** currently points to is either [SQLITE_UPDATE] or [SQLITE_INSERT]. Otherwise,
** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL.
**
** Argument iVal must be greater than or equal to 0, and less than the number
** of columns in the table affected by the current change. Otherwise,
** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
**
** If successful, this function sets *ppValue to point to a protected
** sqlite3_value object containing the iVal'th value from the vector of 
** new row values stored as part of the UPDATE or INSERT change and
** returns SQLITE_OK. If the change is an UPDATE and does not include
** a new value for the requested column, *ppValue is set to NULL and 
** SQLITE_OK returned. The name of the function comes from the fact that 
** this is similar to the "new.*" columns available to update or delete 
** triggers.
**
** If some other error occurs (e.g. an OOM condition), an SQLite error code
** is returned and *ppValue is set to NULL.
*/
int sqlite3changeset_new(
  sqlite3_changeset_iter *pIter,  /* Changeset iterator */
  int iVal,                       /* Column number */
  sqlite3_value **ppValue         /* OUT: New value (or NULL pointer) */
);

/*
** CAPI3REF: Obtain Conflicting Row Values From A Changeset Iterator
**
** This function should only be used with iterator objects passed to a
** conflict-handler callback by [sqlite3changeset_apply()] with either
** [SQLITE_CHANGESET_DATA] or [SQLITE_CHANGESET_CONFLICT]. If this function
** is called on any other iterator, [SQLITE_MISUSE] is returned and *ppValue
** is set to NULL.
**
** Argument iVal must be greater than or equal to 0, and less than the number
** of columns in the table affected by the current change. Otherwise,
** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
**
** If successful, this function sets *ppValue to point to a protected
** sqlite3_value object containing the iVal'th value from the 
** "conflicting row" associated with the current conflict-handler callback
** and returns SQLITE_OK.
**
** If some other error occurs (e.g. an OOM condition), an SQLite error code
** is returned and *ppValue is set to NULL.
*/
int sqlite3changeset_conflict(
  sqlite3_changeset_iter *pIter,  /* Changeset iterator */
  int iVal,                       /* Column number */
  sqlite3_value **ppValue         /* OUT: Value from conflicting row */
);

/*
** CAPI3REF: Determine The Number Of Foreign Key Constraint Violations
**
** This function may only be called with an iterator passed to an
** SQLITE_CHANGESET_FOREIGN_KEY conflict handler callback. In this case
** it sets the output variable to the total number of known foreign key
** violations in the destination database and returns SQLITE_OK.
**
** In all other cases this function returns SQLITE_MISUSE.
*/
int sqlite3changeset_fk_conflicts(
  sqlite3_changeset_iter *pIter,  /* Changeset iterator */
  int *pnOut                      /* OUT: Number of FK violations */
);


/*
** CAPI3REF: Finalize A Changeset Iterator
**
** This function is used to finalize an iterator allocated with
** [sqlite3changeset_start()].
**
** This function should only be called on iterators created using the
** [sqlite3changeset_start()] function. If an application calls this
** function with an iterator passed to a conflict-handler by
** [sqlite3changeset_apply()], [SQLITE_MISUSE] is immediately returned and the
** call has no effect.
**
** If an error was encountered within a call to an sqlite3changeset_xxx()
** function (for example an [SQLITE_CORRUPT] in [sqlite3changeset_next()] or an 
** [SQLITE_NOMEM] in [sqlite3changeset_new()]) then an error code corresponding
** to that error is returned by this function. Otherwise, SQLITE_OK is
** returned. This is to allow the following pattern (pseudo-code):
**
**   sqlite3changeset_start();
**   while( SQLITE_ROW==sqlite3changeset_next() ){
**     // Do something with change.
**   }
**   rc = sqlite3changeset_finalize();
**   if( rc!=SQLITE_OK ){
**     // An error has occurred 
**   }
*/
int sqlite3changeset_finalize(sqlite3_changeset_iter *pIter);

/*
** CAPI3REF: Invert A Changeset
**
** This function is used to "invert" a changeset object. Applying an inverted
** changeset to a database reverses the effects of applying the uninverted
** changeset. Specifically:
**
** <ul>
**   <li> Each DELETE change is changed to an INSERT, and
**   <li> Each INSERT change is changed to a DELETE, and
**   <li> For each UPDATE change, the old.* and new.* values are exchanged.
** </ul>
**
** This function does not change the order in which changes appear within
** the changeset. It merely reverses the sense of each individual change.
**
** If successful, a pointer to a buffer containing the inverted changeset
** is stored in *ppOut, the size of the same buffer is stored in *pnOut, and
** SQLITE_OK is returned. If an error occurs, both *pnOut and *ppOut are
** zeroed and an SQLite error code returned.
**
** It is the responsibility of the caller to eventually call sqlite3_free()
** on the *ppOut pointer to free the buffer allocation following a successful 
** call to this function.
**
** WARNING/TODO: This function currently assumes that the input is a valid
** changeset. If it is not, the results are undefined.
*/
int sqlite3changeset_invert(
  int nIn, const void *pIn,       /* Input changeset */
  int *pnOut, void **ppOut        /* OUT: Inverse of input */
);

/*
** CAPI3REF: Concatenate Two Changeset Objects
**
** This function is used to concatenate two changesets, A and B, into a 
** single changeset. The result is a changeset equivalent to applying
** changeset A followed by changeset B. 
**
** This function combines the two input changesets using an 
** sqlite3_changegroup object. Calling it produces similar results as the
** following code fragment:
**
**   sqlite3_changegroup *pGrp;
**   rc = sqlite3_changegroup_new(&pGrp);
**   if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nA, pA);
**   if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nB, pB);
**   if( rc==SQLITE_OK ){
**     rc = sqlite3changegroup_output(pGrp, pnOut, ppOut);
**   }else{
**     *ppOut = 0;
**     *pnOut = 0;
**   }
**
** Refer to the sqlite3_changegroup documentation below for details.
*/
int sqlite3changeset_concat(
  int nA,                         /* Number of bytes in buffer pA */
  void *pA,                       /* Pointer to buffer containing changeset A */
  int nB,                         /* Number of bytes in buffer pB */
  void *pB,                       /* Pointer to buffer containing changeset B */
  int *pnOut,                     /* OUT: Number of bytes in output changeset */
  void **ppOut                    /* OUT: Buffer containing output changeset */
);


/*
** CAPI3REF: Changegroup Handle
*/
typedef struct sqlite3_changegroup sqlite3_changegroup;

/*
** CAPI3REF: Create A New Changegroup Object
**
** An sqlite3_changegroup object is used to combine two or more changesets
** (or patchsets) into a single changeset (or patchset). A single changegroup
** object may combine changesets or patchsets, but not both. The output is
** always in the same format as the input.
**
** If successful, this function returns SQLITE_OK and populates (*pp) with
** a pointer to a new sqlite3_changegroup object before returning. The caller
** should eventually free the returned object using a call to 
** sqlite3changegroup_delete(). If an error occurs, an SQLite error code
** (i.e. SQLITE_NOMEM) is returned and *pp is set to NULL.
**
** The usual usage pattern for an sqlite3_changegroup object is as follows:
**
** <ul>
**   <li> It is created using a call to sqlite3changegroup_new().
**
**   <li> Zero or more changesets (or patchsets) are added to the object
**        by calling sqlite3changegroup_add().
**
**   <li> The result of combining all input changesets together is obtained 
**        by the application via a call to sqlite3changegroup_output().
**
**   <li> The object is deleted using a call to sqlite3changegroup_delete().
** </ul>
**
** Any number of calls to add() and output() may be made between the calls to
** new() and delete(), and in any order.
**
** As well as the regular sqlite3changegroup_add() and 
** sqlite3changegroup_output() functions, also available are the streaming
** versions sqlite3changegroup_add_strm() and sqlite3changegroup_output_strm().
*/
int sqlite3changegroup_new(sqlite3_changegroup **pp);

/*
** CAPI3REF: Add A Changeset To A Changegroup
**
** Add all changes within the changeset (or patchset) in buffer pData (size
** nData bytes) to the changegroup. 
**
** If the buffer contains a patchset, then all prior calls to this function
** on the same changegroup object must also have specified patchsets. Or, if
** the buffer contains a changeset, so must have the earlier calls to this
** function. Otherwise, SQLITE_ERROR is returned and no changes are added
** to the changegroup.
**
** Rows within the changeset and changegroup are identified by the values in
** their PRIMARY KEY columns. A change in the changeset is considered to
** apply to the same row as a change already present in the changegroup if
** the two rows have the same primary key.
**
** Changes to rows that do not already appear in the changegroup are
** simply copied into it. Or, if both the new changeset and the changegroup
** contain changes that apply to a single row, the final contents of the
** changegroup depends on the type of each change, as follows:
**
** <table border=1 style="margin-left:8ex;margin-right:8ex">
**   <tr><th style="white-space:pre">Existing Change  </th>
**       <th style="white-space:pre">New Change       </th>
**       <th>Output Change
**   <tr><td>INSERT <td>INSERT <td>
**       The new change is ignored. This case does not occur if the new
**       changeset was recorded immediately after the changesets already
**       added to the changegroup.
**   <tr><td>INSERT <td>UPDATE <td>
**       The INSERT change remains in the changegroup. The values in the 
**       INSERT change are modified as if the row was inserted by the
**       existing change and then updated according to the new change.
**   <tr><td>INSERT <td>DELETE <td>
**       The existing INSERT is removed from the changegroup. The DELETE is
**       not added.
**   <tr><td>UPDATE <td>INSERT <td>
**       The new change is ignored. This case does not occur if the new
**       changeset was recorded immediately after the changesets already
**       added to the changegroup.
**   <tr><td>UPDATE <td>UPDATE <td>
**       The existing UPDATE remains within the changegroup. It is amended 
**       so that the accompanying values are as if the row was updated once 
**       by the existing change and then again by the new change.
**   <tr><td>UPDATE <td>DELETE <td>
**       The existing UPDATE is replaced by the new DELETE within the
**       changegroup.
**   <tr><td>DELETE <td>INSERT <td>
**       If one or more of the column values in the row inserted by the
**       new change differ from those in the row deleted by the existing 
**       change, the existing DELETE is replaced by an UPDATE within the
**       changegroup. Otherwise, if the inserted row is exactly the same 
**       as the deleted row, the existing DELETE is simply discarded.
**   <tr><td>DELETE <td>UPDATE <td>
**       The new change is ignored. This case does not occur if the new
**       changeset was recorded immediately after the changesets already
**       added to the changegroup.
**   <tr><td>DELETE <td>DELETE <td>
**       The new change is ignored. This case does not occur if the new
**       changeset was recorded immediately after the changesets already
**       added to the changegroup.
** </table>
**
** If the new changeset contains changes to a table that is already present
** in the changegroup, then the number of columns and the position of the
** primary key columns for the table must be consistent. If this is not the
** case, this function fails with SQLITE_SCHEMA. If the input changeset
** appears to be corrupt and the corruption is detected, SQLITE_CORRUPT is
** returned. Or, if an out-of-memory condition occurs during processing, this
** function returns SQLITE_NOMEM. In all cases, if an error occurs the
** final contents of the changegroup is undefined.
**
** If no error occurs, SQLITE_OK is returned.
*/
int sqlite3changegroup_add(sqlite3_changegroup*, int nData, void *pData);

/*
** CAPI3REF: Obtain A Composite Changeset From A Changegroup
**
** Obtain a buffer containing a changeset (or patchset) representing the
** current contents of the changegroup. If the inputs to the changegroup
** were themselves changesets, the output is a changeset. Or, if the
** inputs were patchsets, the output is also a patchset.
**
** As with the output of the sqlite3session_changeset() and
** sqlite3session_patchset() functions, all changes related to a single
** table are grouped together in the output of this function. Tables appear
** in the same order as for the very first changeset added to the changegroup.
** If the second or subsequent changesets added to the changegroup contain
** changes for tables that do not appear in the first changeset, they are
** appended onto the end of the output changeset, again in the order in
** which they are first encountered.
**
** If an error occurs, an SQLite error code is returned and the output
** variables (*pnData) and (*ppData) are set to 0. Otherwise, SQLITE_OK
** is returned and the output variables are set to the size of and a 
** pointer to the output buffer, respectively. In this case it is the
** responsibility of the caller to eventually free the buffer using a
** call to sqlite3_free().
*/
int sqlite3changegroup_output(
  sqlite3_changegroup*,
  int *pnData,                    /* OUT: Size of output buffer in bytes */
  void **ppData                   /* OUT: Pointer to output buffer */
);

/*
** CAPI3REF: Delete A Changegroup Object
*/
void sqlite3changegroup_delete(sqlite3_changegroup*);

/*
** CAPI3REF: Apply A Changeset To A Database
**
** Apply a changeset to a database. This function attempts to update the
** "main" database attached to handle db with the changes found in the
** changeset passed via the second and third arguments.
**
** The fourth argument (xFilter) passed to this function is the "filter
** callback". If it is not NULL, then for each table affected by at least one
** change in the changeset, the filter callback is invoked with
** the table name as the second argument, and a copy of the context pointer
** passed as the sixth argument to this function as the first. If the "filter
** callback" returns zero, then no attempt is made to apply any changes to 
** the table. Otherwise, if the return value is non-zero or the xFilter
** argument to this function is NULL, all changes related to the table are
** attempted.
**
** For each table that is not excluded by the filter callback, this function 
** tests that the target database contains a compatible table. A table is 
** considered compatible if all of the following are true:
**
** <ul>
**   <li> The table has the same name as the name recorded in the 
**        changeset, and
**   <li> The table has the same number of columns as recorded in the 
**        changeset, and
**   <li> The table has primary key columns in the same position as 
**        recorded in the changeset.
** </ul>
**
** If there is no compatible table, it is not an error, but none of the
** changes associated with the table are applied. A warning message is issued
** via the sqlite3_log() mechanism with the error code SQLITE_SCHEMA. At most
** one such warning is issued for each table in the changeset.
**
** For each change for which there is a compatible table, an attempt is made 
** to modify the table contents according to the UPDATE, INSERT or DELETE 
** change. If a change cannot be applied cleanly, the conflict handler 
** function passed as the fifth argument to sqlite3changeset_apply() may be 
** invoked. A description of exactly when the conflict handler is invoked for 
** each type of change is below.
**
** Unlike the xFilter argument, xConflict may not be passed NULL. The results
** of passing anything other than a valid function pointer as the xConflict
** argument are undefined.
**
** Each time the conflict handler function is invoked, it must return one
** of [SQLITE_CHANGESET_OMIT], [SQLITE_CHANGESET_ABORT] or 
** [SQLITE_CHANGESET_REPLACE]. SQLITE_CHANGESET_REPLACE may only be returned
** if the second argument passed to the conflict handler is either
** SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If the conflict-handler
** returns an illegal value, any changes already made are rolled back and
** the call to sqlite3changeset_apply() returns SQLITE_MISUSE. Different 
** actions are taken by sqlite3changeset_apply() depending on the value
** returned by each invocation of the conflict-handler function. Refer to
** the documentation for the three 
** [SQLITE_CHANGESET_OMIT|available return values] for details.
**
** <dl>
** <dt>DELETE Changes<dd>
**   For each DELETE change, this function checks if the target database 
**   contains a row with the same primary key value (or values) as the 
**   original row values stored in the changeset. If it does, and the values 
**   stored in all non-primary key columns also match the values stored in 
**   the changeset the row is deleted from the target database.
**
**   If a row with matching primary key values is found, but one or more of
**   the non-primary key fields contains a value different from the original
**   row value stored in the changeset, the conflict-handler function is
**   invoked with [SQLITE_CHANGESET_DATA] as the second argument.
**
**   If no row with matching primary key values is found in the database,
**   the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND]
**   passed as the second argument.
**
**   If the DELETE operation is attempted, but SQLite returns SQLITE_CONSTRAINT
**   (which can only happen if a foreign key constraint is violated), the
**   conflict-handler function is invoked with [SQLITE_CHANGESET_CONSTRAINT]
**   passed as the second argument. This includes the case where the DELETE
**   operation is attempted because an earlier call to the conflict handler
**   function returned [SQLITE_CHANGESET_REPLACE].
**
** <dt>INSERT Changes<dd>
**   For each INSERT change, an attempt is made to insert the new row into
**   the database.
**
**   If the attempt to insert the row fails because the database already 
**   contains a row with the same primary key values, the conflict handler
**   function is invoked with the second argument set to 
**   [SQLITE_CHANGESET_CONFLICT].
**
**   If the attempt to insert the row fails because of some other constraint
**   violation (e.g. NOT NULL or UNIQUE), the conflict handler function is 
**   invoked with the second argument set to [SQLITE_CHANGESET_CONSTRAINT].
**   This includes the case where the INSERT operation is re-attempted because 
**   an earlier call to the conflict handler function returned 
**   [SQLITE_CHANGESET_REPLACE].
**
** <dt>UPDATE Changes<dd>
**   For each UPDATE change, this function checks if the target database 
**   contains a row with the same primary key value (or values) as the 
**   original row values stored in the changeset. If it does, and the values 
**   stored in all non-primary key columns also match the values stored in 
**   the changeset the row is updated within the target database.
**
**   If a row with matching primary key values is found, but one or more of
**   the non-primary key fields contains a value different from an original
**   row value stored in the changeset, the conflict-handler function is
**   invoked with [SQLITE_CHANGESET_DATA] as the second argument. Since
**   UPDATE changes only contain values for non-primary key fields that are
**   to be modified, only those fields need to match the original values to
**   avoid the SQLITE_CHANGESET_DATA conflict-handler callback.
**
**   If no row with matching primary key values is found in the database,
**   the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND]
**   passed as the second argument.
**
**   If the UPDATE operation is attempted, but SQLite returns 
**   SQLITE_CONSTRAINT, the conflict-handler function is invoked with 
**   [SQLITE_CHANGESET_CONSTRAINT] passed as the second argument.
**   This includes the case where the UPDATE operation is attempted after 
**   an earlier call to the conflict handler function returned
**   [SQLITE_CHANGESET_REPLACE].  
** </dl>
**
** It is safe to execute SQL statements, including those that write to the
** table that the callback related to, from within the xConflict callback.
** This can be used to further customize the applications conflict
** resolution strategy.
**
** All changes made by this function are enclosed in a savepoint transaction.
** If any other error (aside from a constraint failure when attempting to
** write to the target database) occurs, then the savepoint transaction is
** rolled back, restoring the target database to its original state, and an 
** SQLite error code returned.
*/
int sqlite3changeset_apply(
  sqlite3 *db,                    /* Apply change to "main" db of this handle */
  int nChangeset,                 /* Size of changeset in bytes */
  void *pChangeset,               /* Changeset blob */
  int(*xFilter)(
    void *pCtx,                   /* Copy of sixth arg to _apply() */
    const char *zTab              /* Table name */
  ),
  int(*xConflict)(
    void *pCtx,                   /* Copy of sixth arg to _apply() */
    int eConflict,                /* DATA, MISSING, CONFLICT, CONSTRAINT */
    sqlite3_changeset_iter *p     /* Handle describing change and conflict */
  ),
  void *pCtx                      /* First argument passed to xConflict */
);

/* 
** CAPI3REF: Constants Passed To The Conflict Handler
**
** Values that may be passed as the second argument to a conflict-handler.
**
** <dl>
** <dt>SQLITE_CHANGESET_DATA<dd>
**   The conflict handler is invoked with CHANGESET_DATA as the second argument
**   when processing a DELETE or UPDATE change if a row with the required
**   PRIMARY KEY fields is present in the database, but one or more other 
**   (non primary-key) fields modified by the update do not contain the 
**   expected "before" values.
** 
**   The conflicting row, in this case, is the database row with the matching
**   primary key.
** 
** <dt>SQLITE_CHANGESET_NOTFOUND<dd>
**   The conflict handler is invoked with CHANGESET_NOTFOUND as the second
**   argument when processing a DELETE or UPDATE change if a row with the
**   required PRIMARY KEY fields is not present in the database.
** 
**   There is no conflicting row in this case. The results of invoking the
**   sqlite3changeset_conflict() API are undefined.
** 
** <dt>SQLITE_CHANGESET_CONFLICT<dd>
**   CHANGESET_CONFLICT is passed as the second argument to the conflict
**   handler while processing an INSERT change if the operation would result 
**   in duplicate primary key values.
** 
**   The conflicting row in this case is the database row with the matching
**   primary key.
**
** <dt>SQLITE_CHANGESET_FOREIGN_KEY<dd>
**   If foreign key handling is enabled, and applying a changeset leaves the
**   database in a state containing foreign key violations, the conflict 
**   handler is invoked with CHANGESET_FOREIGN_KEY as the second argument
**   exactly once before the changeset is committed. If the conflict handler
**   returns CHANGESET_OMIT, the changes, including those that caused the
**   foreign key constraint violation, are committed. Or, if it returns
**   CHANGESET_ABORT, the changeset is rolled back.
**
**   No current or conflicting row information is provided. The only function
**   it is possible to call on the supplied sqlite3_changeset_iter handle
**   is sqlite3changeset_fk_conflicts().
** 
** <dt>SQLITE_CHANGESET_CONSTRAINT<dd>
**   If any other constraint violation occurs while applying a change (i.e. 
**   a UNIQUE, CHECK or NOT NULL constraint), the conflict handler is 
**   invoked with CHANGESET_CONSTRAINT as the second argument.
** 
**   There is no conflicting row in this case. The results of invoking the
**   sqlite3changeset_conflict() API are undefined.
**
** </dl>
*/
#define SQLITE_CHANGESET_DATA        1
#define SQLITE_CHANGESET_NOTFOUND    2
#define SQLITE_CHANGESET_CONFLICT    3
#define SQLITE_CHANGESET_CONSTRAINT  4
#define SQLITE_CHANGESET_FOREIGN_KEY 5

/* 
** CAPI3REF: Constants Returned By The Conflict Handler
**
** A conflict handler callback must return one of the following three values.
**
** <dl>
** <dt>SQLITE_CHANGESET_OMIT<dd>
**   If a conflict handler returns this value no special action is taken. The
**   change that caused the conflict is not applied. The session module 
**   continues to the next change in the changeset.
**
** <dt>SQLITE_CHANGESET_REPLACE<dd>
**   This value may only be returned if the second argument to the conflict
**   handler was SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If this
**   is not the case, any changes applied so far are rolled back and the 
**   call to sqlite3changeset_apply() returns SQLITE_MISUSE.
**
**   If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_DATA conflict
**   handler, then the conflicting row is either updated or deleted, depending
**   on the type of change.
**
**   If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_CONFLICT conflict
**   handler, then the conflicting row is removed from the database and a
**   second attempt to apply the change is made. If this second attempt fails,
**   the original row is restored to the database before continuing.
**
** <dt>SQLITE_CHANGESET_ABORT<dd>
**   If this value is returned, any changes applied so far are rolled back 
**   and the call to sqlite3changeset_apply() returns SQLITE_ABORT.
** </dl>
*/
#define SQLITE_CHANGESET_OMIT       0
#define SQLITE_CHANGESET_REPLACE    1
#define SQLITE_CHANGESET_ABORT      2

/*
** CAPI3REF: Streaming Versions of API functions.
**
** The six streaming API xxx_strm() functions serve similar purposes to the 
** corresponding non-streaming API functions:
**
** <table border=1 style="margin-left:8ex;margin-right:8ex">
**   <tr><th>Streaming function<th>Non-streaming equivalent</th>
**   <tr><td>sqlite3changeset_apply_str<td>[sqlite3changeset_apply] 
**   <tr><td>sqlite3changeset_concat_str<td>[sqlite3changeset_concat] 
**   <tr><td>sqlite3changeset_invert_str<td>[sqlite3changeset_invert] 
**   <tr><td>sqlite3changeset_start_str<td>[sqlite3changeset_start] 
**   <tr><td>sqlite3session_changeset_str<td>[sqlite3session_changeset] 
**   <tr><td>sqlite3session_patchset_str<td>[sqlite3session_patchset] 
** </table>
**
** Non-streaming functions that accept changesets (or patchsets) as input
** require that the entire changeset be stored in a single buffer in memory. 
** Similarly, those that return a changeset or patchset do so by returning 
** a pointer to a single large buffer allocated using sqlite3_malloc(). 
** Normally this is convenient. However, if an application running in a 
** low-memory environment is required to handle very large changesets, the
** large contiguous memory allocations required can become onerous.
**
** In order to avoid this problem, instead of a single large buffer, input
** is passed to a streaming API functions by way of a callback function that
** the sessions module invokes to incrementally request input data as it is
** required. In all cases, a pair of API function parameters such as
**
**  <pre>
**  &nbsp;     int nChangeset,
**  &nbsp;     void *pChangeset,
**  </pre>
**
** Is replaced by:
**
**  <pre>
**  &nbsp;     int (*xInput)(void *pIn, void *pData, int *pnData),
**  &nbsp;     void *pIn,
**  </pre>
**
** Each time the xInput callback is invoked by the sessions module, the first
** argument passed is a copy of the supplied pIn context pointer. The second 
** argument, pData, points to a buffer (*pnData) bytes in size. Assuming no 
** error occurs the xInput method should copy up to (*pnData) bytes of data 
** into the buffer and set (*pnData) to the actual number of bytes copied 
** before returning SQLITE_OK. If the input is completely exhausted, (*pnData) 
** should be set to zero to indicate this. Or, if an error occurs, an SQLite 
** error code should be returned. In all cases, if an xInput callback returns
** an error, all processing is abandoned and the streaming API function
** returns a copy of the error code to the caller.
**
** In the case of sqlite3changeset_start_strm(), the xInput callback may be
** invoked by the sessions module at any point during the lifetime of the
** iterator. If such an xInput callback returns an error, the iterator enters
** an error state, whereby all subsequent calls to iterator functions 
** immediately fail with the same error code as returned by xInput.
**
** Similarly, streaming API functions that return changesets (or patchsets)
** return them in chunks by way of a callback function instead of via a
** pointer to a single large buffer. In this case, a pair of parameters such
** as:
**
**  <pre>
**  &nbsp;     int *pnChangeset,
**  &nbsp;     void **ppChangeset,
**  </pre>
**
** Is replaced by:
**
**  <pre>
**  &nbsp;     int (*xOutput)(void *pOut, const void *pData, int nData),
**  &nbsp;     void *pOut
**  </pre>
**
** The xOutput callback is invoked zero or more times to return data to
** the application. The first parameter passed to each call is a copy of the
** pOut pointer supplied by the application. The second parameter, pData,
** points to a buffer nData bytes in size containing the chunk of output
** data being returned. If the xOutput callback successfully processes the
** supplied data, it should return SQLITE_OK to indicate success. Otherwise,
** it should return some other SQLite error code. In this case processing
** is immediately abandoned and the streaming API function returns a copy
** of the xOutput error code to the application.
**
** The sessions module never invokes an xOutput callback with the third 
** parameter set to a value less than or equal to zero. Other than this,
** no guarantees are made as to the size of the chunks of data returned.
*/
int sqlite3changeset_apply_strm(
  sqlite3 *db,                    /* Apply change to "main" db of this handle */
  int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */
  void *pIn,                                          /* First arg for xInput */
  int(*xFilter)(
    void *pCtx,                   /* Copy of sixth arg to _apply() */
    const char *zTab              /* Table name */
  ),
  int(*xConflict)(
    void *pCtx,                   /* Copy of sixth arg to _apply() */
    int eConflict,                /* DATA, MISSING, CONFLICT, CONSTRAINT */
    sqlite3_changeset_iter *p     /* Handle describing change and conflict */
  ),
  void *pCtx                      /* First argument passed to xConflict */
);
int sqlite3changeset_concat_strm(
  int (*xInputA)(void *pIn, void *pData, int *pnData),
  void *pInA,
  int (*xInputB)(void *pIn, void *pData, int *pnData),
  void *pInB,
  int (*xOutput)(void *pOut, const void *pData, int nData),
  void *pOut
);
int sqlite3changeset_invert_strm(
  int (*xInput)(void *pIn, void *pData, int *pnData),
  void *pIn,
  int (*xOutput)(void *pOut, const void *pData, int nData),
  void *pOut
);
int sqlite3changeset_start_strm(
  sqlite3_changeset_iter **pp,
  int (*xInput)(void *pIn, void *pData, int *pnData),
  void *pIn
);
int sqlite3session_changeset_strm(
  sqlite3_session *pSession,
  int (*xOutput)(void *pOut, const void *pData, int nData),
  void *pOut
);
int sqlite3session_patchset_strm(
  sqlite3_session *pSession,
  int (*xOutput)(void *pOut, const void *pData, int nData),
  void *pOut
);
int sqlite3changegroup_add_strm(sqlite3_changegroup*, 
    int (*xInput)(void *pIn, void *pData, int *pnData),
    void *pIn
);
int sqlite3changegroup_output_strm(sqlite3_changegroup*,
    int (*xOutput)(void *pOut, const void *pData, int nData), 
    void *pOut
);


/*
** Make sure we can call this stuff from C++.
*/
#ifdef __cplusplus
}
#endif

#endif  /* !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) */

/******** End of sqlite3session.h *********/
/******** Begin file fts5.h *********/
/*
** 2014 May 31
**
** 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.
**
******************************************************************************
**
** Interfaces to extend FTS5. Using the interfaces defined in this file, 
** FTS5 may be extended with:
**
**     * custom tokenizers, and
**     * custom auxiliary functions.
*/


#ifndef _FTS5_H
#define _FTS5_H


#ifdef __cplusplus
extern "C" {
#endif

/*************************************************************************
** CUSTOM AUXILIARY FUNCTIONS
**
** Virtual table implementations may overload SQL functions by implementing
** the sqlite3_module.xFindFunction() method.
*/

typedef struct Fts5ExtensionApi Fts5ExtensionApi;
typedef struct Fts5Context Fts5Context;
typedef struct Fts5PhraseIter Fts5PhraseIter;

typedef void (*fts5_extension_function)(
  const Fts5ExtensionApi *pApi,   /* API offered by current FTS version */
  Fts5Context *pFts,              /* First arg to pass to pApi functions */
  sqlite3_context *pCtx,          /* Context for returning result/error */
  int nVal,                       /* Number of values in apVal[] array */
  sqlite3_value **apVal           /* Array of trailing arguments */
);

struct Fts5PhraseIter {
  const unsigned char *a;
  const unsigned char *b;
};

/*
** EXTENSION API FUNCTIONS
**
** xUserData(pFts):
**   Return a copy of the context pointer the extension function was 
**   registered with.
**
** xColumnTotalSize(pFts, iCol, pnToken):
**   If parameter iCol is less than zero, set output variable *pnToken
**   to the total number of tokens in the FTS5 table. Or, if iCol is
**   non-negative but less than the number of columns in the table, return
**   the total number of tokens in column iCol, considering all rows in 
**   the FTS5 table.
**
**   If parameter iCol is greater than or equal to the number of columns
**   in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g.
**   an OOM condition or IO error), an appropriate SQLite error code is 
**   returned.
**
** xColumnCount(pFts):
**   Return the number of columns in the table.
**
** xColumnSize(pFts, iCol, pnToken):
**   If parameter iCol is less than zero, set output variable *pnToken
**   to the total number of tokens in the current row. Or, if iCol is
**   non-negative but less than the number of columns in the table, set
**   *pnToken to the number of tokens in column iCol of the current row.
**
**   If parameter iCol is greater than or equal to the number of columns
**   in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g.
**   an OOM condition or IO error), an appropriate SQLite error code is 
**   returned.
**
**   This function may be quite inefficient if used with an FTS5 table
**   created with the "columnsize=0" option.
**
** xColumnText:
**   This function attempts to retrieve the text of column iCol of the
**   current document. If successful, (*pz) is set to point to a buffer
**   containing the text in utf-8 encoding, (*pn) is set to the size in bytes
**   (not characters) of the buffer and SQLITE_OK is returned. Otherwise,
**   if an error occurs, an SQLite error code is returned and the final values
**   of (*pz) and (*pn) are undefined.
**
** xPhraseCount:
**   Returns the number of phrases in the current query expression.
**
** xPhraseSize:
**   Returns the number of tokens in phrase iPhrase of the query. Phrases
**   are numbered starting from zero.
**
** xInstCount:
**   Set *pnInst to the total number of occurrences of all phrases within
**   the query within the current row. Return SQLITE_OK if successful, or
**   an error code (i.e. SQLITE_NOMEM) if an error occurs.
**
**   This API can be quite slow if used with an FTS5 table created with the
**   "detail=none" or "detail=column" option. If the FTS5 table is created 
**   with either "detail=none" or "detail=column" and "content=" option 
**   (i.e. if it is a contentless table), then this API always returns 0.
**
** xInst:
**   Query for the details of phrase match iIdx within the current row.
**   Phrase matches are numbered starting from zero, so the iIdx argument
**   should be greater than or equal to zero and smaller than the value
**   output by xInstCount().
**
**   Usually, output parameter *piPhrase is set to the phrase number, *piCol
**   to the column in which it occurs and *piOff the token offset of the
**   first token of the phrase. The exception is if the table was created
**   with the offsets=0 option specified. In this case *piOff is always
**   set to -1.
**
**   Returns SQLITE_OK if successful, or an error code (i.e. SQLITE_NOMEM) 
**   if an error occurs.
**
**   This API can be quite slow if used with an FTS5 table created with the
**   "detail=none" or "detail=column" option. 
**
** xRowid:
**   Returns the rowid of the current row.
**
** xTokenize:
**   Tokenize text using the tokenizer belonging to the FTS5 table.
**
** xQueryPhrase(pFts5, iPhrase, pUserData, xCallback):
**   This API function is used to query the FTS table for phrase iPhrase
**   of the current query. Specifically, a query equivalent to:
**
**       ... FROM ftstable WHERE ftstable MATCH $p ORDER BY rowid
**
**   with $p set to a phrase equivalent to the phrase iPhrase of the
**   current query is executed. Any column filter that applies to
**   phrase iPhrase of the current query is included in $p. For each 
**   row visited, the callback function passed as the fourth argument 
**   is invoked. The context and API objects passed to the callback 
**   function may be used to access the properties of each matched row.
**   Invoking Api.xUserData() returns a copy of the pointer passed as 
**   the third argument to pUserData.
**
**   If the callback function returns any value other than SQLITE_OK, the
**   query is abandoned and the xQueryPhrase function returns immediately.
**   If the returned value is SQLITE_DONE, xQueryPhrase returns SQLITE_OK.
**   Otherwise, the error code is propagated upwards.
**
**   If the query runs to completion without incident, SQLITE_OK is returned.
**   Or, if some error occurs before the query completes or is aborted by
**   the callback, an SQLite error code is returned.
**
**
** xSetAuxdata(pFts5, pAux, xDelete)
**
**   Save the pointer passed as the second argument as the extension functions 
**   "auxiliary data". The pointer may then be retrieved by the current or any
**   future invocation of the same fts5 extension function made as part of
**   of the same MATCH query using the xGetAuxdata() API.
**
**   Each extension function is allocated a single auxiliary data slot for
**   each FTS query (MATCH expression). If the extension function is invoked 
**   more than once for a single FTS query, then all invocations share a 
**   single auxiliary data context.
**
**   If there is already an auxiliary data pointer when this function is
**   invoked, then it is replaced by the new pointer. If an xDelete callback
**   was specified along with the original pointer, it is invoked at this
**   point.
**
**   The xDelete callback, if one is specified, is also invoked on the
**   auxiliary data pointer after the FTS5 query has finished.
**
**   If an error (e.g. an OOM condition) occurs within this function, an
**   the auxiliary data is set to NULL and an error code returned. If the
**   xDelete parameter was not NULL, it is invoked on the auxiliary data
**   pointer before returning.
**
**
** xGetAuxdata(pFts5, bClear)
**
**   Returns the current auxiliary data pointer for the fts5 extension 
**   function. See the xSetAuxdata() method for details.
**
**   If the bClear argument is non-zero, then the auxiliary data is cleared
**   (set to NULL) before this function returns. In this case the xDelete,
**   if any, is not invoked.
**
**
** xRowCount(pFts5, pnRow)
**
**   This function is used to retrieve the total number of rows in the table.
**   In other words, the same value that would be returned by:
**
**        SELECT count(*) FROM ftstable;
**
** xPhraseFirst()
**   This function is used, along with type Fts5PhraseIter and the xPhraseNext
**   method, to iterate through all instances of a single query phrase within
**   the current row. This is the same information as is accessible via the
**   xInstCount/xInst APIs. While the xInstCount/xInst APIs are more convenient
**   to use, this API may be faster under some circumstances. To iterate 
**   through instances of phrase iPhrase, use the following code:
**
**       Fts5PhraseIter iter;
**       int iCol, iOff;
**       for(pApi->xPhraseFirst(pFts, iPhrase, &iter, &iCol, &iOff);
**           iCol>=0;
**           pApi->xPhraseNext(pFts, &iter, &iCol, &iOff)
**       ){
**         // An instance of phrase iPhrase at offset iOff of column iCol
**       }
**
**   The Fts5PhraseIter structure is defined above. Applications should not
**   modify this structure directly - it should only be used as shown above
**   with the xPhraseFirst() and xPhraseNext() API methods (and by
**   xPhraseFirstColumn() and xPhraseNextColumn() as illustrated below).
**
**   This API can be quite slow if used with an FTS5 table created with the
**   "detail=none" or "detail=column" option. If the FTS5 table is created 
**   with either "detail=none" or "detail=column" and "content=" option 
**   (i.e. if it is a contentless table), then this API always iterates
**   through an empty set (all calls to xPhraseFirst() set iCol to -1).
**
** xPhraseNext()
**   See xPhraseFirst above.
**
** xPhraseFirstColumn()
**   This function and xPhraseNextColumn() are similar to the xPhraseFirst()
**   and xPhraseNext() APIs described above. The difference is that instead
**   of iterating through all instances of a phrase in the current row, these
**   APIs are used to iterate through the set of columns in the current row
**   that contain one or more instances of a specified phrase. For example:
**
**       Fts5PhraseIter iter;
**       int iCol;
**       for(pApi->xPhraseFirstColumn(pFts, iPhrase, &iter, &iCol);
**           iCol>=0;
**           pApi->xPhraseNextColumn(pFts, &iter, &iCol)
**       ){
**         // Column iCol contains at least one instance of phrase iPhrase
**       }
**
**   This API can be quite slow if used with an FTS5 table created with the
**   "detail=none" option. If the FTS5 table is created with either 
**   "detail=none" "content=" option (i.e. if it is a contentless table), 
**   then this API always iterates through an empty set (all calls to 
**   xPhraseFirstColumn() set iCol to -1).
**
**   The information accessed using this API and its companion
**   xPhraseFirstColumn() may also be obtained using xPhraseFirst/xPhraseNext
**   (or xInst/xInstCount). The chief advantage of this API is that it is
**   significantly more efficient than those alternatives when used with
**   "detail=column" tables.  
**
** xPhraseNextColumn()
**   See xPhraseFirstColumn above.
*/
struct Fts5ExtensionApi {
  int iVersion;                   /* Currently always set to 3 */

  void *(*xUserData)(Fts5Context*);

  int (*xColumnCount)(Fts5Context*);
  int (*xRowCount)(Fts5Context*, sqlite3_int64 *pnRow);
  int (*xColumnTotalSize)(Fts5Context*, int iCol, sqlite3_int64 *pnToken);

  int (*xTokenize)(Fts5Context*, 
    const char *pText, int nText, /* Text to tokenize */
    void *pCtx,                   /* Context passed to xToken() */
    int (*xToken)(void*, int, const char*, int, int, int)       /* Callback */
  );

  int (*xPhraseCount)(Fts5Context*);
  int (*xPhraseSize)(Fts5Context*, int iPhrase);

  int (*xInstCount)(Fts5Context*, int *pnInst);
  int (*xInst)(Fts5Context*, int iIdx, int *piPhrase, int *piCol, int *piOff);

  sqlite3_int64 (*xRowid)(Fts5Context*);
  int (*xColumnText)(Fts5Context*, int iCol, const char **pz, int *pn);
  int (*xColumnSize)(Fts5Context*, int iCol, int *pnToken);

  int (*xQueryPhrase)(Fts5Context*, int iPhrase, void *pUserData,
    int(*)(const Fts5ExtensionApi*,Fts5Context*,void*)
  );
  int (*xSetAuxdata)(Fts5Context*, void *pAux, void(*xDelete)(void*));
  void *(*xGetAuxdata)(Fts5Context*, int bClear);

  int (*xPhraseFirst)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*, int*);
  void (*xPhraseNext)(Fts5Context*, Fts5PhraseIter*, int *piCol, int *piOff);

  int (*xPhraseFirstColumn)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*);
  void (*xPhraseNextColumn)(Fts5Context*, Fts5PhraseIter*, int *piCol);
};

/* 
** CUSTOM AUXILIARY FUNCTIONS
*************************************************************************/

/*************************************************************************
** CUSTOM TOKENIZERS
**
** Applications may also register custom tokenizer types. A tokenizer 
** is registered by providing fts5 with a populated instance of the 
** following structure. All structure methods must be defined, setting
** any member of the fts5_tokenizer struct to NULL leads to undefined
** behaviour. The structure methods are expected to function as follows:
**
** xCreate:
**   This function is used to allocate and initialize a tokenizer instance.
**   A tokenizer instance is required to actually tokenize text.
**
**   The first argument passed to this function is a copy of the (void*)
**   pointer provided by the application when the fts5_tokenizer object
**   was registered with FTS5 (the third argument to xCreateTokenizer()). 
**   The second and third arguments are an array of nul-terminated strings
**   containing the tokenizer arguments, if any, specified following the
**   tokenizer name as part of the CREATE VIRTUAL TABLE statement used
**   to create the FTS5 table.
**
**   The final argument is an output variable. If successful, (*ppOut) 
**   should be set to point to the new tokenizer handle and SQLITE_OK
**   returned. If an error occurs, some value other than SQLITE_OK should
**   be returned. In this case, fts5 assumes that the final value of *ppOut 
**   is undefined.
**
** xDelete:
**   This function is invoked to delete a tokenizer handle previously
**   allocated using xCreate(). Fts5 guarantees that this function will
**   be invoked exactly once for each successful call to xCreate().
**
** xTokenize:
**   This function is expected to tokenize the nText byte string indicated 
**   by argument pText. pText may or may not be nul-terminated. The first
**   argument passed to this function is a pointer to an Fts5Tokenizer object
**   returned by an earlier call to xCreate().
**
**   The second argument indicates the reason that FTS5 is requesting
**   tokenization of the supplied text. This is always one of the following
**   four values:
**
**   <ul><li> <b>FTS5_TOKENIZE_DOCUMENT</b> - A document is being inserted into
**            or removed from the FTS table. The tokenizer is being invoked to
**            determine the set of tokens to add to (or delete from) the
**            FTS index.
**
**       <li> <b>FTS5_TOKENIZE_QUERY</b> - A MATCH query is being executed 
**            against the FTS index. The tokenizer is being called to tokenize 
**            a bareword or quoted string specified as part of the query.
**
**       <li> <b>(FTS5_TOKENIZE_QUERY | FTS5_TOKENIZE_PREFIX)</b> - Same as
**            FTS5_TOKENIZE_QUERY, except that the bareword or quoted string is
**            followed by a "*" character, indicating that the last token
**            returned by the tokenizer will be treated as a token prefix.
**
**       <li> <b>FTS5_TOKENIZE_AUX</b> - The tokenizer is being invoked to 
**            satisfy an fts5_api.xTokenize() request made by an auxiliary
**            function. Or an fts5_api.xColumnSize() request made by the same
**            on a columnsize=0 database.  
**   </ul>
**
**   For each token in the input string, the supplied callback xToken() must
**   be invoked. The first argument to it should be a copy of the pointer
**   passed as the second argument to xTokenize(). The third and fourth
**   arguments are a pointer to a buffer containing the token text, and the
**   size of the token in bytes. The 4th and 5th arguments are the byte offsets
**   of the first byte of and first byte immediately following the text from
**   which the token is derived within the input.
**
**   The second argument passed to the xToken() callback ("tflags") should
**   normally be set to 0. The exception is if the tokenizer supports 
**   synonyms. In this case see the discussion below for details.
**
**   FTS5 assumes the xToken() callback is invoked for each token in the 
**   order that they occur within the input text.
**
**   If an xToken() callback returns any value other than SQLITE_OK, then
**   the tokenization should be abandoned and the xTokenize() method should
**   immediately return a copy of the xToken() return value. Or, if the
**   input buffer is exhausted, xTokenize() should return SQLITE_OK. Finally,
**   if an error occurs with the xTokenize() implementation itself, it
**   may abandon the tokenization and return any error code other than
**   SQLITE_OK or SQLITE_DONE.
**
** SYNONYM SUPPORT
**
**   Custom tokenizers may also support synonyms. Consider a case in which a
**   user wishes to query for a phrase such as "first place". Using the 
**   built-in tokenizers, the FTS5 query 'first + place' will match instances
**   of "first place" within the document set, but not alternative forms
**   such as "1st place". In some applications, it would be better to match
**   all instances of "first place" or "1st place" regardless of which form
**   the user specified in the MATCH query text.
**
**   There are several ways to approach this in FTS5:
**
**   <ol><li> By mapping all synonyms to a single token. In this case, the 
**            In the above example, this means that the tokenizer returns the
**            same token for inputs "first" and "1st". Say that token is in
**            fact "first", so that when the user inserts the document "I won
**            1st place" entries are added to the index for tokens "i", "won",
**            "first" and "place". If the user then queries for '1st + place',
**            the tokenizer substitutes "first" for "1st" and the query works
**            as expected.
**
**       <li> By adding multiple synonyms for a single term to the FTS index.
**            In this case, when tokenizing query text, the tokenizer may 
**            provide multiple synonyms for a single term within the document.
**            FTS5 then queries the index for each synonym individually. For
**            example, faced with the query:
**
**   <codeblock>
**     ... MATCH 'first place'</codeblock>
**
**            the tokenizer offers both "1st" and "first" as synonyms for the
**            first token in the MATCH query and FTS5 effectively runs a query 
**            similar to:
**
**   <codeblock>
**     ... MATCH '(first OR 1st) place'</codeblock>
**
**            except that, for the purposes of auxiliary functions, the query
**            still appears to contain just two phrases - "(first OR 1st)" 
**            being treated as a single phrase.
**
**       <li> By adding multiple synonyms for a single term to the FTS index.
**            Using this method, when tokenizing document text, the tokenizer
**            provides multiple synonyms for each token. So that when a 
**            document such as "I won first place" is tokenized, entries are
**            added to the FTS index for "i", "won", "first", "1st" and
**            "place".
**
**            This way, even if the tokenizer does not provide synonyms
**            when tokenizing query text (it should not - to do would be
**            inefficient), it doesn't matter if the user queries for 
**            'first + place' or '1st + place', as there are entires in the
**            FTS index corresponding to both forms of the first token.
**   </ol>
**
**   Whether it is parsing document or query text, any call to xToken that
**   specifies a <i>tflags</i> argument with the FTS5_TOKEN_COLOCATED bit
**   is considered to supply a synonym for the previous token. For example,
**   when parsing the document "I won first place", a tokenizer that supports
**   synonyms would call xToken() 5 times, as follows:
**
**   <codeblock>
**       xToken(pCtx, 0, "i",                      1,  0,  1);
**       xToken(pCtx, 0, "won",                    3,  2,  5);
**       xToken(pCtx, 0, "first",                  5,  6, 11);
**       xToken(pCtx, FTS5_TOKEN_COLOCATED, "1st", 3,  6, 11);
**       xToken(pCtx, 0, "place",                  5, 12, 17);
**</codeblock>
**
**   It is an error to specify the FTS5_TOKEN_COLOCATED flag the first time
**   xToken() is called. Multiple synonyms may be specified for a single token
**   by making multiple calls to xToken(FTS5_TOKEN_COLOCATED) in sequence. 
**   There is no limit to the number of synonyms that may be provided for a
**   single token.
**
**   In many cases, method (1) above is the best approach. It does not add 
**   extra data to the FTS index or require FTS5 to query for multiple terms,
**   so it is efficient in terms of disk space and query speed. However, it
**   does not support prefix queries very well. If, as suggested above, the
**   token "first" is subsituted for "1st" by the tokenizer, then the query:
**
**   <codeblock>
**     ... MATCH '1s*'</codeblock>
**
**   will not match documents that contain the token "1st" (as the tokenizer
**   will probably not map "1s" to any prefix of "first").
**
**   For full prefix support, method (3) may be preferred. In this case, 
**   because the index contains entries for both "first" and "1st", prefix
**   queries such as 'fi*' or '1s*' will match correctly. However, because
**   extra entries are added to the FTS index, this method uses more space
**   within the database.
**
**   Method (2) offers a midpoint between (1) and (3). Using this method,
**   a query such as '1s*' will match documents that contain the literal 
**   token "1st", but not "first" (assuming the tokenizer is not able to
**   provide synonyms for prefixes). However, a non-prefix query like '1st'
**   will match against "1st" and "first". This method does not require
**   extra disk space, as no extra entries are added to the FTS index. 
**   On the other hand, it may require more CPU cycles to run MATCH queries,
**   as separate queries of the FTS index are required for each synonym.
**
**   When using methods (2) or (3), it is important that the tokenizer only
**   provide synonyms when tokenizing document text (method (2)) or query
**   text (method (3)), not both. Doing so will not cause any errors, but is
**   inefficient.
*/
typedef struct Fts5Tokenizer Fts5Tokenizer;
typedef struct fts5_tokenizer fts5_tokenizer;
struct fts5_tokenizer {
  int (*xCreate)(void*, const char **azArg, int nArg, Fts5Tokenizer **ppOut);
  void (*xDelete)(Fts5Tokenizer*);
  int (*xTokenize)(Fts5Tokenizer*, 
      void *pCtx,
      int flags,            /* Mask of FTS5_TOKENIZE_* flags */
      const char *pText, int nText, 
      int (*xToken)(
        void *pCtx,         /* Copy of 2nd argument to xTokenize() */
        int tflags,         /* Mask of FTS5_TOKEN_* flags */
        const char *pToken, /* Pointer to buffer containing token */
        int nToken,         /* Size of token in bytes */
        int iStart,         /* Byte offset of token within input text */
        int iEnd            /* Byte offset of end of token within input text */
      )
  );
};

/* Flags that may be passed as the third argument to xTokenize() */
#define FTS5_TOKENIZE_QUERY     0x0001
#define FTS5_TOKENIZE_PREFIX    0x0002
#define FTS5_TOKENIZE_DOCUMENT  0x0004
#define FTS5_TOKENIZE_AUX       0x0008

/* Flags that may be passed by the tokenizer implementation back to FTS5
** as the third argument to the supplied xToken callback. */
#define FTS5_TOKEN_COLOCATED    0x0001      /* Same position as prev. token */

/*
** END OF CUSTOM TOKENIZERS
*************************************************************************/

/*************************************************************************
** FTS5 EXTENSION REGISTRATION API
*/
typedef struct fts5_api fts5_api;
struct fts5_api {
  int iVersion;                   /* Currently always set to 2 */

  /* Create a new tokenizer */
  int (*xCreateTokenizer)(
    fts5_api *pApi,
    const char *zName,
    void *pContext,
    fts5_tokenizer *pTokenizer,
    void (*xDestroy)(void*)
  );

  /* Find an existing tokenizer */
  int (*xFindTokenizer)(
    fts5_api *pApi,
    const char *zName,
    void **ppContext,
    fts5_tokenizer *pTokenizer
  );

  /* Create a new auxiliary function */
  int (*xCreateFunction)(
    fts5_api *pApi,
    const char *zName,
    void *pContext,
    fts5_extension_function xFunction,
    void (*xDestroy)(void*)
  );
};

/*
** END OF REGISTRATION API
*************************************************************************/

#ifdef __cplusplus
}  /* end of the 'extern "C"' block */
#endif

#endif /* _FTS5_H */

/******** End of fts5.h *********/