sqllogictest

/******************************************************************************
** This file is an amalgamation of many separate C source files from SQLite
** version 3.8.4.  By combining all the individual C code files into this 
** single large file, the entire code can be compiled as a single translation
** unit.  This allows many compilers to do optimizations that would not be
** possible if the files were compiled separately.  Performance improvements
** of 5% or more are commonly seen when SQLite is compiled as a single
** translation unit.
**
** This file is all you need to compile SQLite.  To use SQLite in other

#define SQLITE_AMALGAMATION 1
#ifndef SQLITE_PRIVATE
# define SQLITE_PRIVATE static
#endif
#ifndef SQLITE_API
# define SQLITE_API
#endif
/************** Begin file sqliteInt.h ***************************************/
/*
** 2001 September 15
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_

/*
** These #defines should enable >2GB file support on POSIX if the
** underlying operating system supports it.  If the OS lacks
** large file support, or if the OS is windows, these should be no-ops.
**
** Ticket #2739:  The _LARGEFILE_SOURCE macro must appear before any
** system #includes.  Hence, this block of code must be the very first
** code in all source files.
**
** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch
** on the compiler command line.  This is necessary if you are compiling
** on a recent machine (ex: Red Hat 7.2) but you want your code to work
** on an older machine (ex: Red Hat 6.0).  If you compile on Red Hat 7.2
** without this option, LFS is enable.  But LFS does not exist in the kernel
** in Red Hat 6.0, so the code won't work.  Hence, for maximum binary
** portability you should omit LFS.
**
** The previous paragraph was written in 2005.  (This paragraph is written
** on 2008-11-28.) These days, all Linux kernels support large files, so
** you should probably leave LFS enabled.  But some embedded platforms might
** lack LFS in which case the SQLITE_DISABLE_LFS macro might still be useful.
**
** Similar is true for Mac OS X.  LFS is only supported on Mac OS X 9 and later.
*/
#ifndef SQLITE_DISABLE_LFS
# define _LARGE_FILE       1
# ifndef _FILE_OFFSET_BITS
#   define _FILE_OFFSET_BITS 64
# endif
# define _LARGEFILE_SOURCE 1
#endif

/* The public SQLite interface.  The _FILE_OFFSET_BITS macro must appear
** first in QNX.
*/
/************** Include sqlite3.h in the middle of sqliteInt.h ***************/
/************** Begin file sqlite3.h *****************************************/
/*
** 2001 September 15
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**

** string contains the date and time of the check-in (UTC) and an SHA1
** hash of the entire source tree.
**
** See also: [sqlite3_libversion()],
** [sqlite3_libversion_number()], [sqlite3_sourceid()],
** [sqlite_version()] and [sqlite_source_id()].
*/
#define SQLITE_VERSION        "3.8.4"
#define SQLITE_VERSION_NUMBER 3008004
#define SQLITE_SOURCE_ID      "2014-03-05 19:04:46 0723effc9ccae7c660fb847b36ce9324e0cb5042"

/*
** CAPI3REF: Run-Time Library Version Numbers
** KEYWORDS: sqlite3_version, sqlite3_sourceid
**
** These interfaces provide the same information as the [SQLITE_VERSION],
** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros

#define SQLITE_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
#define SQLITE_TESTCTRL_NEVER_CORRUPT           20
#define SQLITE_TESTCTRL_VDBE_COVERAGE           21
#define SQLITE_TESTCTRL_LAST                    21

/*
** CAPI3REF: SQLite Runtime Status
**
** ^This interface is 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

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

#endif  /* ifndef _SQLITE3RTREE_H_ */


/************** End of sqlite3.h *********************************************/
/************** Continuing where we left off in sqliteInt.h ******************/












































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

SQLITE_PRIVATE int sqlite3BtreePrevious(BtCursor*, int *pRes);
SQLITE_PRIVATE int sqlite3BtreeKeySize(BtCursor*, i64 *pSize);
SQLITE_PRIVATE int sqlite3BtreeKey(BtCursor*, u32 offset, u32 amt, void*);
SQLITE_PRIVATE const void *sqlite3BtreeKeyFetch(BtCursor*, u32 *pAmt);
SQLITE_PRIVATE const void *sqlite3BtreeDataFetch(BtCursor*, u32 *pAmt);
SQLITE_PRIVATE int sqlite3BtreeDataSize(BtCursor*, u32 *pSize);
SQLITE_PRIVATE int sqlite3BtreeData(BtCursor*, u32 offset, u32 amt, void*);



SQLITE_PRIVATE char *sqlite3BtreeIntegrityCheck(Btree*, int *aRoot, int nRoot, int, int*);
SQLITE_PRIVATE struct Pager *sqlite3BtreePager(Btree*);

SQLITE_PRIVATE int sqlite3BtreePutData(BtCursor*, u32 offset, u32 amt, void*);
SQLITE_PRIVATE void sqlite3BtreeCacheOverflow(BtCursor *);
SQLITE_PRIVATE void sqlite3BtreeClearCursor(BtCursor *);

    SubProgram *pProgram;  /* Used when p4type is P4_SUBPROGRAM */
    int (*xAdvance)(BtCursor *, int *);
  } p4;
#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
  char *zComment;          /* Comment to improve readability */
#endif
#ifdef VDBE_PROFILE
  u32 cnt;                 /* Number of times this instruction was executed */
  u64 cycles;              /* Total time spent executing this instruction */
#endif
#ifdef SQLITE_VDBE_COVERAGE
  int iSrcLine;            /* Source-code line that generated this opcode */
#endif
};
typedef struct VdbeOp VdbeOp;


/*
** A sub-routine used to implement a trigger program.
*/

#define OP_Vacuum         13
#define OP_VFilter        14 /* synopsis: iPlan=r[P3] zPlan='P4'           */
#define OP_VUpdate        15 /* synopsis: data=r[P3@P2]                    */
#define OP_Goto           16
#define OP_Gosub          17
#define OP_Return         18
#define OP_Not            19 /* same as TK_NOT, synopsis: r[P2]= !r[P1]    */
#define OP_InitCoroutine  20
#define OP_EndCoroutine   21
#define OP_Yield          22
#define OP_HaltIfNull     23 /* synopsis: if r[P3]=null halt               */
#define OP_Halt           24
#define OP_Integer        25 /* synopsis: r[P2]=P1                         */
#define OP_Int64          26 /* synopsis: r[P2]=P4                         */
#define OP_String         27 /* synopsis: r[P2]='P4' (len=P1)              */
#define OP_Null           28 /* synopsis: r[P2..P3]=NULL                   */
#define OP_SoftNull       29 /* synopsis: r[P1]=NULL                       */
#define OP_Blob           30 /* synopsis: r[P2]=P4 (len=P1)                */
#define OP_Variable       31 /* synopsis: r[P2]=parameter(P1,P4)           */
#define OP_Move           32 /* synopsis: r[P2@P3]=r[P1@P3]                */
#define OP_Copy           33 /* synopsis: r[P2@P3+1]=r[P1@P3+1]            */
#define OP_SCopy          34 /* synopsis: r[P2]=r[P1]                      */
#define OP_ResultRow      35 /* synopsis: output=r[P1@P2]                  */
#define OP_CollSeq        36
#define OP_AddImm         37 /* synopsis: r[P1]=r[P1]+P2                   */
#define OP_MustBeInt      38
#define OP_RealAffinity   39
#define OP_Permutation    40
#define OP_Compare        41
#define OP_Jump           42
#define OP_Once           43
#define OP_If             44
#define OP_IfNot          45
#define OP_Column         46 /* synopsis: r[P3]=PX                         */
#define OP_Affinity       47 /* synopsis: affinity(r[P1@P2])               */
#define OP_MakeRecord     48 /* synopsis: r[P3]=mkrec(r[P1@P2])            */
#define OP_Count          49 /* synopsis: r[P2]=count()                    */
#define OP_ReadCookie     50
#define OP_SetCookie      51

#define OP_OpenRead       52 /* synopsis: root=P2 iDb=P3                   */
#define OP_OpenWrite      53 /* synopsis: root=P2 iDb=P3                   */
#define OP_OpenAutoindex  54 /* synopsis: nColumn=P2                       */
#define OP_OpenEphemeral  55 /* synopsis: nColumn=P2                       */
#define OP_SorterOpen     56
#define OP_OpenPseudo     57 /* synopsis: P3 columns in r[P2]              */
#define OP_Close          58
#define OP_SeekLT         59
#define OP_SeekLE         60
#define OP_SeekGE         61
#define OP_SeekGT         62
#define OP_Seek           63 /* synopsis: intkey=r[P2]                     */
#define OP_NoConflict     64 /* synopsis: key=r[P3@P4]                     */
#define OP_NotFound       65 /* synopsis: key=r[P3@P4]                     */
#define OP_Found          66 /* synopsis: key=r[P3@P4]                     */
#define OP_NotExists      67 /* synopsis: intkey=r[P3]                     */
#define OP_Sequence       68 /* synopsis: r[P2]=rowid                      */
#define OP_NewRowid       69 /* synopsis: r[P2]=rowid                      */
#define OP_Insert         70 /* synopsis: intkey=r[P3] data=r[P2]          */


#define OP_Or             71 /* same as TK_OR, synopsis: r[P3]=(r[P1] || r[P2]) */
#define OP_And            72 /* same as TK_AND, synopsis: r[P3]=(r[P1] && r[P2]) */
#define OP_InsertInt      73 /* synopsis: intkey=P3 data=r[P2]             */
#define OP_Delete         74
#define OP_ResetCount     75


#define OP_IsNull         76 /* same as TK_ISNULL, synopsis: if r[P1]==NULL goto P2 */
#define OP_NotNull        77 /* same as TK_NOTNULL, synopsis: if r[P1]!=NULL goto P2 */
#define OP_Ne             78 /* same as TK_NE, synopsis: if r[P1]!=r[P3] goto P2 */
#define OP_Eq             79 /* same as TK_EQ, synopsis: if r[P1]==r[P3] goto P2 */
#define OP_Gt             80 /* same as TK_GT, synopsis: if r[P1]>r[P3] goto P2 */
#define OP_Le             81 /* same as TK_LE, synopsis: if r[P1]<=r[P3] goto P2 */
#define OP_Lt             82 /* same as TK_LT, synopsis: if r[P1]<r[P3] goto P2 */
#define OP_Ge             83 /* same as TK_GE, synopsis: if r[P1]>=r[P3] goto P2 */
#define OP_SorterCompare  84 /* synopsis: if key(P1)!=rtrim(r[P3],P4) goto P2 */
#define OP_BitAnd         85 /* same as TK_BITAND, synopsis: r[P3]=r[P1]&r[P2] */
#define OP_BitOr          86 /* same as TK_BITOR, synopsis: r[P3]=r[P1]|r[P2] */
#define OP_ShiftLeft      87 /* same as TK_LSHIFT, synopsis: r[P3]=r[P2]<<r[P1] */
#define OP_ShiftRight     88 /* same as TK_RSHIFT, synopsis: r[P3]=r[P2]>>r[P1] */
#define OP_Add            89 /* same as TK_PLUS, synopsis: r[P3]=r[P1]+r[P2] */
#define OP_Subtract       90 /* same as TK_MINUS, synopsis: r[P3]=r[P2]-r[P1] */
#define OP_Multiply       91 /* same as TK_STAR, synopsis: r[P3]=r[P1]*r[P2] */
#define OP_Divide         92 /* same as TK_SLASH, synopsis: r[P3]=r[P2]/r[P1] */
#define OP_Remainder      93 /* same as TK_REM, synopsis: r[P3]=r[P2]%r[P1] */
#define OP_Concat         94 /* same as TK_CONCAT, synopsis: r[P3]=r[P2]+r[P1] */
#define OP_SorterData     95 /* synopsis: r[P2]=data                       */
#define OP_BitNot         96 /* same as TK_BITNOT, synopsis: r[P1]= ~r[P1] */
#define OP_String8        97 /* same as TK_STRING, synopsis: r[P2]='P4'    */
#define OP_RowKey         98 /* synopsis: r[P2]=key                        */
#define OP_RowData        99 /* synopsis: r[P2]=data                       */
#define OP_Rowid         100 /* synopsis: r[P2]=rowid                      */
#define OP_NullRow       101
#define OP_Last          102
#define OP_SorterSort    103
#define OP_Sort          104
#define OP_Rewind        105
#define OP_SorterInsert  106
#define OP_IdxInsert     107 /* synopsis: key=r[P2]                        */
#define OP_IdxDelete     108 /* synopsis: key=r[P2@P3]                     */
#define OP_IdxRowid      109 /* synopsis: r[P2]=rowid                      */
#define OP_IdxLE         110 /* synopsis: key=r[P3@P4]                     */
#define OP_IdxGT         111 /* synopsis: key=r[P3@P4]                     */
#define OP_IdxLT         112 /* synopsis: key=r[P3@P4]                     */
#define OP_IdxGE         113 /* synopsis: key=r[P3@P4]                     */
#define OP_Destroy       114
#define OP_Clear         115
#define OP_CreateIndex   116 /* synopsis: r[P2]=root iDb=P1                */
#define OP_CreateTable   117 /* synopsis: r[P2]=root iDb=P1                */
#define OP_ParseSchema   118
#define OP_LoadAnalysis  119
#define OP_DropTable     120
#define OP_DropIndex     121
#define OP_DropTrigger   122
#define OP_IntegrityCk   123
#define OP_RowSetAdd     124 /* synopsis: rowset(P1)=r[P2]                 */
#define OP_RowSetRead    125 /* synopsis: r[P3]=rowset(P1)                 */
#define OP_RowSetTest    126 /* synopsis: if r[P3] in rowset(P1) goto P2   */
#define OP_Program       127
#define OP_Param         128
#define OP_FkCounter     129 /* synopsis: fkctr[P1]+=P2                    */
#define OP_FkIfZero      130 /* synopsis: if fkctr[P1]==0 goto P2          */
#define OP_MemMax        131 /* synopsis: r[P1]=max(r[P1],r[P2])           */
#define OP_IfPos         132 /* synopsis: if r[P1]>0 goto P2               */




#define OP_Real          133 /* same as TK_FLOAT, synopsis: r[P2]=P4       */
#define OP_IfNeg         134 /* synopsis: if r[P1]<0 goto P2               */
#define OP_IfZero        135 /* synopsis: r[P1]+=P3, if r[P1]==0 goto P2   */
#define OP_AggFinal      136 /* synopsis: accum=r[P1] N=P2                 */
#define OP_IncrVacuum    137
#define OP_Expire        138
#define OP_TableLock     139 /* synopsis: iDb=P1 root=P2 write=P3          */
#define OP_VBegin        140
#define OP_VCreate       141
#define OP_VDestroy      142




#define OP_ToText        143 /* same as TK_TO_TEXT                         */
#define OP_ToBlob        144 /* same as TK_TO_BLOB                         */
#define OP_ToNumeric     145 /* same as TK_TO_NUMERIC                      */
#define OP_ToInt         146 /* same as TK_TO_INT                          */
#define OP_ToReal        147 /* same as TK_TO_REAL                         */
#define OP_VOpen         148
#define OP_VColumn       149 /* synopsis: r[P3]=vcolumn(P2)                */
#define OP_VNext         150
#define OP_VRename       151
#define OP_Pagecount     152
#define OP_MaxPgcnt      153
#define OP_Init          154 /* synopsis: Start at P2                      */
#define OP_Noop          155
#define OP_Explain       156


/* Properties such as "out2" or "jump" that are specified in
** comments following the "case" for each opcode in the vdbe.c
** are encoded into bitvectors as follows:
*/
#define OPFLG_JUMP            0x0001  /* jump:  P2 holds jmp target */
#define OPFLG_OUT2_PRERELEASE 0x0002  /* out2-prerelease: */
#define OPFLG_IN1             0x0004  /* in1:   P1 is an input */
#define OPFLG_IN2             0x0008  /* in2:   P2 is an input */
#define OPFLG_IN3             0x0010  /* in3:   P3 is an input */
#define OPFLG_OUT2            0x0020  /* out2:  P2 is an output */
#define OPFLG_OUT3            0x0040  /* out3:  P3 is an output */
#define OPFLG_INITIALIZER {\
/*   0 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01, 0x01,\
/*   8 */ 0x01, 0x01, 0x00, 0x00, 0x02, 0x00, 0x01, 0x00,\
/*  16 */ 0x01, 0x01, 0x04, 0x24, 0x01, 0x04, 0x05, 0x10,\
/*  24 */ 0x00, 0x02, 0x02, 0x02, 0x02, 0x00, 0x02, 0x02,\
/*  32 */ 0x00, 0x00, 0x20, 0x00, 0x00, 0x04, 0x05, 0x04,\
/*  40 */ 0x00, 0x00, 0x01, 0x01, 0x05, 0x05, 0x00, 0x00,\
/*  48 */ 0x00, 0x02, 0x02, 0x10, 0x00, 0x00, 0x00, 0x00,\
/*  56 */ 0x00, 0x00, 0x00, 0x11, 0x11, 0x11, 0x11, 0x08,\
/*  64 */ 0x11, 0x11, 0x11, 0x11, 0x02, 0x02, 0x00, 0x4c,\
/*  72 */ 0x4c, 0x00, 0x00, 0x00, 0x05, 0x05, 0x15, 0x15,\
/*  80 */ 0x15, 0x15, 0x15, 0x15, 0x00, 0x4c, 0x4c, 0x4c,\
/*  88 */ 0x4c, 0x4c, 0x4c, 0x4c, 0x4c, 0x4c, 0x4c, 0x00,\
/*  96 */ 0x24, 0x02, 0x00, 0x00, 0x02, 0x00, 0x01, 0x01,\
/* 104 */ 0x01, 0x01, 0x08, 0x08, 0x00, 0x02, 0x01, 0x01,\
/* 112 */ 0x01, 0x01, 0x02, 0x00, 0x02, 0x02, 0x00, 0x00,\
/* 120 */ 0x00, 0x00, 0x00, 0x00, 0x0c, 0x45, 0x15, 0x01,\
/* 128 */ 0x02, 0x00, 0x01, 0x08, 0x05, 0x02, 0x05, 0x05,\
/* 136 */ 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x04,\
/* 144 */ 0x04, 0x04, 0x04, 0x04, 0x00, 0x00, 0x01, 0x00,\
/* 152 */ 0x02, 0x02, 0x01, 0x00, 0x00,}

/************** End of opcodes.h *********************************************/
/************** Continuing where we left off in vdbe.h ***********************/

/*
** Prototypes for the VDBE interface.  See comments on the implementation
** for a description of what each of these routines does.
*/
SQLITE_PRIVATE Vdbe *sqlite3VdbeCreate(Parse*);
SQLITE_PRIVATE int sqlite3VdbeAddOp0(Vdbe*,int);
SQLITE_PRIVATE int sqlite3VdbeAddOp1(Vdbe*,int,int);
SQLITE_PRIVATE int sqlite3VdbeAddOp2(Vdbe*,int,int,int);
SQLITE_PRIVATE int sqlite3VdbeAddOp3(Vdbe*,int,int,int,int);
SQLITE_PRIVATE int sqlite3VdbeAddOp4(Vdbe*,int,int,int,int,const char *zP4,int);
SQLITE_PRIVATE int sqlite3VdbeAddOp4Int(Vdbe*,int,int,int,int,int);
SQLITE_PRIVATE int sqlite3VdbeAddOpList(Vdbe*, int nOp, VdbeOpList const *aOp, int iLineno);
SQLITE_PRIVATE void sqlite3VdbeAddParseSchemaOp(Vdbe*,int,char*);
SQLITE_PRIVATE void sqlite3VdbeChangeP1(Vdbe*, u32 addr, int P1);
SQLITE_PRIVATE void sqlite3VdbeChangeP2(Vdbe*, u32 addr, int P2);
SQLITE_PRIVATE void sqlite3VdbeChangeP3(Vdbe*, u32 addr, int P3);
SQLITE_PRIVATE void sqlite3VdbeChangeP5(Vdbe*, u8 P5);
SQLITE_PRIVATE void sqlite3VdbeJumpHere(Vdbe*, int addr);
SQLITE_PRIVATE void sqlite3VdbeChangeToNoop(Vdbe*, int addr);

SQLITE_PRIVATE sqlite3_value *sqlite3VdbeGetBoundValue(Vdbe*, int, u8);
SQLITE_PRIVATE void sqlite3VdbeSetVarmask(Vdbe*, int);
#ifndef SQLITE_OMIT_TRACE
SQLITE_PRIVATE   char *sqlite3VdbeExpandSql(Vdbe*, const char*);
#endif

SQLITE_PRIVATE void sqlite3VdbeRecordUnpack(KeyInfo*,int,const void*,UnpackedRecord*);
SQLITE_PRIVATE int sqlite3VdbeRecordCompare(int,const void*,const UnpackedRecord*,int);
SQLITE_PRIVATE UnpackedRecord *sqlite3VdbeAllocUnpackedRecord(KeyInfo *, char *, int, char **);

typedef int (*RecordCompare)(int,const void*,const UnpackedRecord*,int);
SQLITE_PRIVATE RecordCompare sqlite3VdbeFindCompare(UnpackedRecord*);

#ifndef SQLITE_OMIT_TRIGGER
SQLITE_PRIVATE void sqlite3VdbeLinkSubProgram(Vdbe *, SubProgram *);
#endif

/* Use SQLITE_ENABLE_COMMENTS to enable generation of extra comments on
** each VDBE opcode.

# endif
#else
# define VdbeComment(X)
# define VdbeNoopComment(X)
# define VdbeModuleComment(X)
#endif

/*
** The VdbeCoverage macros are used to set a coverage testing point
** for VDBE branch instructions.  The coverage testing points are line
** numbers in the sqlite3.c source file.  VDBE branch coverage testing
** only works with an amalagmation build.  That's ok since a VDBE branch
** coverage build designed for testing the test suite only.  No application
** should ever ship with VDBE branch coverage measuring turned on.
**
**    VdbeCoverage(v)                  // Mark the previously coded instruction
**                                     // as a branch
**
**    VdbeCoverageIf(v, conditional)   // Mark previous if conditional true
**
**    VdbeCoverageAlwaysTaken(v)       // Previous branch is always taken
**
**    VdbeCoverageNeverTaken(v)        // Previous branch is never taken
**
** Every VDBE branch operation must be tagged with one of the macros above.
** If not, then when "make test" is run with -DSQLITE_VDBE_COVERAGE and
** -DSQLITE_DEBUG then an ALWAYS() will fail in the vdbeTakeBranch()
** routine in vdbe.c, alerting the developer to the missed tag.
*/
#ifdef SQLITE_VDBE_COVERAGE
SQLITE_PRIVATE   void sqlite3VdbeSetLineNumber(Vdbe*,int);
# define VdbeCoverage(v) sqlite3VdbeSetLineNumber(v,__LINE__)
# define VdbeCoverageIf(v,x) if(x)sqlite3VdbeSetLineNumber(v,__LINE__)
# define VdbeCoverageAlwaysTaken(v) sqlite3VdbeSetLineNumber(v,2);
# define VdbeCoverageNeverTaken(v) sqlite3VdbeSetLineNumber(v,1);
#else
# define VdbeCoverage(v)
# define VdbeCoverageIf(v,x)
# define VdbeCoverageAlwaysTaken(v)
# define VdbeCoverageNeverTaken(v)
#endif

#endif

/************** End of vdbe.h ************************************************/
/************** Continuing where we left off in sqliteInt.h ******************/
/************** Include pager.h in the middle of sqliteInt.h *****************/
/************** Begin file pager.h *******************************************/
/*

#define OptimizationEnabled(db, mask)   1
#endif

/*
** Return true if it OK to factor constant expressions into the initialization
** code. The argument is a Parse object for the code generator.
*/
#define ConstFactorOk(P) ((P)->okConstFactor)


/*
** Possible values for the sqlite.magic field.
** The numbers are obtained at random and have no special meaning, other
** than being distinct from one another.
*/
#define SQLITE_MAGIC_OPEN     0xa029a697  /* Database is open */

** affinity value. 
*/
#define SQLITE_AFF_MASK     0x67

/*
** Additional bit values that can be ORed with an affinity without
** changing the affinity.
**
** The SQLITE_NOTNULL flag is a combination of NULLEQ and JUMPIFNULL.
** It causes an assert() to fire if either operand to a comparison
** operator is NULL.  It is added to certain comparison operators to
** prove that the operands are always NOT NULL.
*/
#define SQLITE_JUMPIFNULL   0x08  /* jumps if either operand is NULL */
#define SQLITE_STOREP2      0x10  /* Store result in reg[P2] rather than jump */
#define SQLITE_NULLEQ       0x80  /* NULL=NULL */
#define SQLITE_NOTNULL      0x88  /* Assert that operands are never NULL */

/*
** An object of this type is created for each virtual table present in
** the database schema. 
**
** If the database schema is shared, then there is one instance of this
** structure for each database connection (sqlite3*) that uses the shared

** Records are used to store the content of a table row and to store
** the key of an index.  A blob encoding of a record is created by
** the OP_MakeRecord opcode of the VDBE and is disassembled by the
** OP_Column opcode.
**
** This structure holds a record that has already been disassembled
** into its constituent fields.
**
** The r1 and r2 member variables are only used by the optimized comparison
** functions vdbeRecordCompareInt() and vdbeRecordCompareString().
*/
struct UnpackedRecord {
  KeyInfo *pKeyInfo;  /* Collation and sort-order information */
  u16 nField;         /* Number of entries in apMem[] */
  i8 default_rc;      /* Comparison result if keys are equal */
  Mem *aMem;          /* Values */
  int r1;             /* Value to return if (lhs > rhs) */
  int r2;             /* Value to return if (rhs < lhs) */
};







/*
** Each SQL index is represented in memory by an
** instance of the following structure.
**
** The columns of the table that are to be indexed are described
** by the aiColumn[] field of this structure.  For example, suppose

** But sqlite3SrcListShiftJoinType() later shifts the jointypes so that each
** jointype expresses the join between the table and the previous table.
**
** In the colUsed field, the high-order bit (bit 63) is set if the table
** contains more than 63 columns and the 64-th or later column is used.
*/
struct SrcList {
  int nSrc;        /* Number of tables or subqueries in the FROM clause */
  u32 nAlloc;      /* Number of entries allocated in a[] below */
  struct SrcList_item {
    Schema *pSchema;  /* Schema to which this item is fixed */
    char *zDatabase;  /* Name of database holding this table */
    char *zName;      /* Name of the table */
    char *zAlias;     /* The "B" part of a "A AS B" phrase.  zName is the "A" */
    Table *pTab;      /* An SQL table corresponding to zName */
    Select *pSelect;  /* A SELECT statement used in place of a table name */
    int addrFillSub;  /* Address of subroutine to manifest a subquery */
    int regReturn;    /* Register holding return address of addrFillSub */
    int regResult;    /* Registers holding results of a co-routine */
    u8 jointype;      /* Type of join between this able and the previous */
    unsigned notIndexed :1;    /* True if there is a NOT INDEXED clause */
    unsigned isCorrelated :1;  /* True if sub-query is correlated */
    unsigned viaCoroutine :1;  /* Implemented as a co-routine */
    unsigned isRecursive :1;   /* True for recursive reference in WITH */
#ifndef SQLITE_OMIT_EXPLAIN
    u8 iSelectId;     /* If pSelect!=0, the id of the sub-select in EQP */

  SrcList *pSrc;         /* The FROM clause */
  Expr *pWhere;          /* The WHERE clause */
  ExprList *pGroupBy;    /* The GROUP BY clause */
  Expr *pHaving;         /* The HAVING clause */
  ExprList *pOrderBy;    /* The ORDER BY clause */
  Select *pPrior;        /* Prior select in a compound select statement */
  Select *pNext;         /* Next select to the left in a compound */

  Expr *pLimit;          /* LIMIT expression. NULL means not used. */
  Expr *pOffset;         /* OFFSET expression. NULL means not used. */
  With *pWith;           /* WITH clause attached to this select. Or NULL. */
};

/*
** Allowed values for Select.selFlags.  The "SF" prefix stands for
** "Select Flag".
*/
#define SF_Distinct        0x0001  /* Output should be DISTINCT */
#define SF_Resolved        0x0002  /* Identifiers have been resolved */
#define SF_Aggregate       0x0004  /* Contains aggregate functions */
#define SF_UsesEphemeral   0x0008  /* Uses the OpenEphemeral opcode */
#define SF_Expanded        0x0010  /* sqlite3SelectExpand() called on this */
#define SF_HasTypeInfo     0x0020  /* FROM subqueries have Table metadata */
#define SF_UseSorter       0x0040  /* Sort using a sorter */
#define SF_Values          0x0080  /* Synthesized from VALUES clause */
#define SF_Materialize     0x0100  /* NOT USED */
#define SF_NestedFrom      0x0200  /* Part of a parenthesized FROM clause */
#define SF_MaybeConvert    0x0400  /* Need convertCompoundSelectToSubquery() */
#define SF_Recursive       0x0800  /* The recursive part of a recursive CTE */
#define SF_Compound        0x1000  /* Part of a compound query */


/*
** The results of a SELECT can be distributed in several ways, as defined
** by one of the following macros.  The "SRT" prefix means "SELECT Result
** Type".
**

  char *zErrMsg;       /* An error message */
  Vdbe *pVdbe;         /* An engine for executing database bytecode */
  int rc;              /* Return code from execution */
  u8 colNamesSet;      /* TRUE after OP_ColumnName has been issued to pVdbe */
  u8 checkSchema;      /* Causes schema cookie check after an error */
  u8 nested;           /* Number of nested calls to the parser/code generator */
  u8 nTempReg;         /* Number of temporary registers in aTempReg[] */

  u8 nColCache;        /* Number of entries in aColCache[] */
  u8 iColCache;        /* Next entry in aColCache[] to replace */
  u8 isMultiWrite;     /* True if statement may modify/insert multiple rows */
  u8 mayAbort;         /* True if statement may throw an ABORT exception */
  u8 hasCompound;      /* Need to invoke convertCompoundSelectToSubquery() */
  u8 okConstFactor;    /* OK to factor out constants */
  int aTempReg[8];     /* Holding area for temporary registers */
  int nRangeReg;       /* Size of the temporary register block */
  int iRangeReg;       /* First register in temporary register block */
  int nErr;            /* Number of errors seen */
  int nTab;            /* Number of previously allocated VDBE cursors */
  int nMem;            /* Number of memory cells used so far */
  int nSet;            /* Number of sets used so far */
  int nOnce;           /* Number of OP_Once instructions so far */
  int nOpAlloc;        /* Number of slots allocated for Vdbe.aOp[] */


  int iFixedOp;        /* Never back out opcodes iFixedOp-1 or earlier */
  int ckBase;          /* Base register of data during check constraints */
  int iPartIdxTab;     /* Table corresponding to a partial index */
  int iCacheLevel;     /* ColCache valid when aColCache[].iLevel<=iCacheLevel */
  int iCacheCnt;       /* Counter used to generate aColCache[].lru values */
  int nLabel;          /* Number of labels used */
  int *aLabel;         /* Space to hold the labels */
  struct yColCache {
    int iTable;           /* Table cursor number */
    i16 iColumn;          /* Table column number */
    u8 tempReg;           /* iReg is a temp register that needs to be freed */
    int iLevel;           /* Nesting level */
    int iReg;             /* Reg with value of this column. 0 means none. */
    int lru;              /* Least recently used entry has the smallest value */
  } aColCache[SQLITE_N_COLCACHE];  /* One for each column cache entry */
  ExprList *pConstExpr;/* Constant expressions */
  Token constraintName;/* Name of the constraint currently being parsed */
  yDbMask writeMask;   /* Start a write transaction on these databases */
  yDbMask cookieMask;  /* Bitmask of schema verified databases */

  int cookieValue[SQLITE_MAX_ATTACHED+2];  /* Values of cookies to verify */
  int regRowid;        /* Register holding rowid of CREATE TABLE entry */
  int regRoot;         /* Register holding root page number for new objects */
  int nMaxArg;         /* Max args passed to user function by sub-program */

#ifndef SQLITE_OMIT_SHARED_CACHE
  int nTableLock;        /* Number of locks in aTableLock */
  TableLock *aTableLock; /* Required table locks for shared-cache mode */
#endif
  AutoincInfo *pAinc;  /* Information about AUTOINCREMENT counters */

  /* Information used while coding trigger programs. */
  Parse *pToplevel;    /* Parse structure for main program (or NULL) */
  Table *pTriggerTab;  /* Table triggers are being coded for */
  int addrCrTab;       /* Address of OP_CreateTable opcode on CREATE TABLE */
  int addrSkipPK;      /* Address of instruction to skip PRIMARY KEY index */
  u32 nQueryLoop;      /* Est number of iterations of a query (10*log2(N)) */
  u32 oldmask;         /* Mask of old.* columns referenced */
  u32 newmask;         /* Mask of new.* columns referenced */
  u8 eTriggerOp;       /* TK_UPDATE, TK_INSERT or TK_DELETE */
  u8 eOrconf;          /* Default ON CONFLICT policy for trigger steps */
  u8 disableTriggers;  /* True to disable triggers */

  /************************************************************************
  ** Above is constant between recursions.  Below is reset before and after
  ** each recursion.  The boundary between these two regions is determined
  ** using offsetof(Parse,nVar) so the nVar field must be the first field
  ** in the recursive region.
  ************************************************************************/

  int nVar;                 /* Number of '?' variables seen in the SQL so far */
  int nzVar;                /* Number of available slots in azVar[] */
  u8 iPkSortOrder;          /* ASC or DESC for INTEGER PRIMARY KEY */
  u8 bFreeWith;             /* True if pWith should be freed with parser */
  u8 explain;               /* True if the EXPLAIN flag is found on the query */
#ifndef SQLITE_OMIT_VIRTUALTABLE
  u8 declareVtab;           /* True if inside sqlite3_declare_vtab() */
  int nVtabLock;            /* Number of virtual tables to lock */
#endif
  int nAlias;               /* Number of aliased result set columns */
  int nHeight;              /* Expression tree height of current sub-select */

#ifndef SQLITE_OMIT_VIRTUALTABLE
  Token sArg;               /* Complete text of a module argument */
  Table **apVtabLock;       /* Pointer to virtual tables needing locking */
#endif
  Table *pZombieTab;        /* List of Table objects to delete after code gen */
  TriggerPrg *pTriggerPrg;  /* Linked list of coded triggers */
  With *pWith;              /* Current WITH clause, or NULL */

};

/*
** Return true if currently inside an sqlite3_declare_vtab() call.
*/
#ifdef SQLITE_OMIT_VIRTUALTABLE
  #define IN_DECLARE_VTAB 0

  void (*xLog)(void*,int,const char*); /* Function for logging */
  void *pLogArg;                       /* First argument to xLog() */
  int bLocaltimeFault;              /* True to fail localtime() calls */
#ifdef SQLITE_ENABLE_SQLLOG
  void(*xSqllog)(void*,sqlite3*,const char*, int);
  void *pSqllogArg;
#endif
#ifdef SQLITE_VDBE_COVERAGE
  /* The following callback (if not NULL) is invoked on every VDBE branch
  ** operation.  Set the callback using SQLITE_TESTCTRL_VDBE_COVERAGE.
  */
  void (*xVdbeBranch)(void*,int iSrcLine,u8 eThis,u8 eMx);  /* Callback */
  void *pVdbeBranchArg;                                     /* 1st argument */
#endif
};

/*
** This macro is used inside of assert() statements to indicate that
** the assert is only valid on a well-formed database.  Instead of:
**
**     assert( X );

#ifndef SQLITE_OMIT_AUTOINCREMENT
SQLITE_PRIVATE   void sqlite3AutoincrementBegin(Parse *pParse);
SQLITE_PRIVATE   void sqlite3AutoincrementEnd(Parse *pParse);
#else
# define sqlite3AutoincrementBegin(X)
# define sqlite3AutoincrementEnd(X)
#endif

SQLITE_PRIVATE void sqlite3Insert(Parse*, SrcList*, Select*, IdList*, int);
SQLITE_PRIVATE void *sqlite3ArrayAllocate(sqlite3*,void*,int,int*,int*);
SQLITE_PRIVATE IdList *sqlite3IdListAppend(sqlite3*, IdList*, Token*);
SQLITE_PRIVATE int sqlite3IdListIndex(IdList*,const char*);
SQLITE_PRIVATE SrcList *sqlite3SrcListEnlarge(sqlite3*, SrcList*, int, int);
SQLITE_PRIVATE SrcList *sqlite3SrcListAppend(sqlite3*, SrcList*, Token*, Token*);
SQLITE_PRIVATE SrcList *sqlite3SrcListAppendFromTerm(Parse*, SrcList*, Token*, Token*,

SQLITE_PRIVATE void sqlite3ExprCodeMove(Parse*, int, int, int);
SQLITE_PRIVATE void sqlite3ExprCacheStore(Parse*, int, int, int);
SQLITE_PRIVATE void sqlite3ExprCachePush(Parse*);
SQLITE_PRIVATE void sqlite3ExprCachePop(Parse*, int);
SQLITE_PRIVATE void sqlite3ExprCacheRemove(Parse*, int, int);
SQLITE_PRIVATE void sqlite3ExprCacheClear(Parse*);
SQLITE_PRIVATE void sqlite3ExprCacheAffinityChange(Parse*, int, int);
SQLITE_PRIVATE void sqlite3ExprCode(Parse*, Expr*, int);
SQLITE_PRIVATE void sqlite3ExprCodeFactorable(Parse*, Expr*, int);
SQLITE_PRIVATE void sqlite3ExprCodeAtInit(Parse*, Expr*, int, u8);
SQLITE_PRIVATE int sqlite3ExprCodeTemp(Parse*, Expr*, int*);
SQLITE_PRIVATE int sqlite3ExprCodeTarget(Parse*, Expr*, int);
SQLITE_PRIVATE void sqlite3ExprCodeAndCache(Parse*, Expr*, int);
SQLITE_PRIVATE int sqlite3ExprCodeExprList(Parse*, ExprList*, int, u8);
#define SQLITE_ECEL_DUP      0x01  /* Deep, not shallow copies */
#define SQLITE_ECEL_FACTOR   0x02  /* Factor out constant terms */
SQLITE_PRIVATE void sqlite3ExprIfTrue(Parse*, Expr*, int, int);
SQLITE_PRIVATE void sqlite3ExprIfFalse(Parse*, Expr*, int, int);
SQLITE_PRIVATE Table *sqlite3FindTable(sqlite3*,const char*, const char*);
SQLITE_PRIVATE Table *sqlite3LocateTable(Parse*,int isView,const char*, const char*);

SQLITE_PRIVATE void sqlite3CloseSavepoints(sqlite3 *);
SQLITE_PRIVATE void sqlite3LeaveMutexAndCloseZombie(sqlite3*);
SQLITE_PRIVATE int sqlite3ExprIsConstant(Expr*);
SQLITE_PRIVATE int sqlite3ExprIsConstantNotJoin(Expr*);
SQLITE_PRIVATE int sqlite3ExprIsConstantOrFunction(Expr*);
SQLITE_PRIVATE int sqlite3ExprIsInteger(Expr*, int*);
SQLITE_PRIVATE int sqlite3ExprCanBeNull(const Expr*);

SQLITE_PRIVATE int sqlite3ExprNeedsNoAffinityChange(const Expr*, char);
SQLITE_PRIVATE int sqlite3IsRowid(const char*);
SQLITE_PRIVATE void sqlite3GenerateRowDelete(Parse*,Table*,Trigger*,int,int,int,i16,u8,u8,u8);
SQLITE_PRIVATE void sqlite3GenerateRowIndexDelete(Parse*, Table*, int, int, int*);
SQLITE_PRIVATE int sqlite3GenerateIndexKey(Parse*, Index*, int, int, int, int*,Index*,int);
SQLITE_PRIVATE void sqlite3GenerateConstraintChecks(Parse*,Table*,int*,int,int,int,int,
                                     u8,u8,int,int*);

  (u8)(((u32)(B)<(u32)0x80)?(*(A)=(unsigned char)(B)),1:\
  sqlite3PutVarint32((A),(B)))
#define getVarint    sqlite3GetVarint
#define putVarint    sqlite3PutVarint


SQLITE_PRIVATE const char *sqlite3IndexAffinityStr(Vdbe *, Index *);
SQLITE_PRIVATE void sqlite3TableAffinity(Vdbe*, Table*, int);
SQLITE_PRIVATE char sqlite3CompareAffinity(Expr *pExpr, char aff2);
SQLITE_PRIVATE int sqlite3IndexAffinityOk(Expr *pExpr, char idx_affinity);
SQLITE_PRIVATE char sqlite3ExprAffinity(Expr *pExpr);
SQLITE_PRIVATE int sqlite3Atoi64(const char*, i64*, int, u8);
SQLITE_PRIVATE void sqlite3Error(sqlite3*, int, const char*,...);
SQLITE_PRIVATE void *sqlite3HexToBlob(sqlite3*, const char *z, int n);
SQLITE_PRIVATE u8 sqlite3HexToInt(int h);

  "OMIT_CHECK",
#endif
#ifdef SQLITE_OMIT_COMPLETE
  "OMIT_COMPLETE",
#endif
#ifdef SQLITE_OMIT_COMPOUND_SELECT
  "OMIT_COMPOUND_SELECT",
#endif
#ifdef SQLITE_OMIT_CTE
  "OMIT_CTE",
#endif
#ifdef SQLITE_OMIT_DATETIME_FUNCS
  "OMIT_DATETIME_FUNCS",
#endif
#ifdef SQLITE_OMIT_DECLTYPE
  "OMIT_DECLTYPE",
#endif

  i8 iDb;               /* Index of cursor database in db->aDb[] (or -1) */
  u8 nullRow;           /* True if pointing to a row with no data */
  u8 rowidIsValid;      /* True if lastRowid is valid */
  u8 deferredMoveto;    /* A call to sqlite3BtreeMoveto() is needed */
  Bool useRandomRowid:1;/* Generate new record numbers semi-randomly */
  Bool isTable:1;       /* True if a table requiring integer keys */
  Bool isOrdered:1;     /* True if the underlying table is BTREE_UNORDERED */

  sqlite3_vtab_cursor *pVtabCursor;  /* The cursor for a virtual table */
  i64 seqCount;         /* Sequence counter */
  i64 movetoTarget;     /* Argument to the deferred sqlite3BtreeMoveto() */
  i64 lastRowid;        /* Rowid being deleted by OP_Delete */
  VdbeSorter *pSorter;  /* Sorter object for OP_SorterOpen cursors */

  /* Cached information about the header for the data record that the

    int nZero;          /* Used when bit MEM_Zero is set in flags */
    FuncDef *pDef;      /* Used only when flags==MEM_Agg */
    RowSet *pRowSet;    /* Used only when flags==MEM_RowSet */
    VdbeFrame *pFrame;  /* Used when flags==MEM_Frame */
  } u;
  int n;              /* Number of characters in string value, excluding '\0' */
  u16 flags;          /* Some combination of MEM_Null, MEM_Str, MEM_Dyn, etc. */

  u8  enc;            /* SQLITE_UTF8, SQLITE_UTF16BE, SQLITE_UTF16LE */
#ifdef SQLITE_DEBUG
  Mem *pScopyFrom;    /* This Mem is a shallow copy of pScopyFrom */
  void *pFiller;      /* So that sizeof(Mem) is a multiple of 8 */
#endif
  void (*xDel)(void *);  /* If not null, call this function to delete Mem.z */
  char *zMalloc;      /* Dynamic buffer allocated by sqlite3_malloc() */

** flags may coexist with the MEM_Str flag.
*/
#define MEM_Null      0x0001   /* Value is NULL */
#define MEM_Str       0x0002   /* Value is a string */
#define MEM_Int       0x0004   /* Value is an integer */
#define MEM_Real      0x0008   /* Value is a real number */
#define MEM_Blob      0x0010   /* Value is a BLOB */
#define MEM_AffMask   0x001f   /* Mask of affinity bits */
#define MEM_RowSet    0x0020   /* Value is a RowSet object */
#define MEM_Frame     0x0040   /* Value is a VdbeFrame object */
#define MEM_Undefined 0x0080   /* Value is undefined */
#define MEM_Cleared   0x0100   /* NULL set by OP_Null, not from data */
#define MEM_TypeMask  0x01ff   /* Mask of type bits */


/* Whenever Mem contains a valid string or blob representation, one of
** the following flags must be set to determine the memory management
** policy for Mem.z.  The MEM_Term flag tells us whether or not the
** string is \000 or \u0000 terminated
*/
#define MEM_Term      0x0200   /* String rep is nul terminated */
#define MEM_Dyn       0x0400   /* Need to call Mem.xDel() on Mem.z */
#define MEM_Static    0x0800   /* Mem.z points to a static string */
#define MEM_Ephem     0x1000   /* Mem.z points to an ephemeral string */
#define MEM_Agg       0x2000   /* Mem.z points to an agg function context */
#define MEM_Zero      0x4000   /* Mem.i contains count of 0s appended to blob */
#ifdef SQLITE_OMIT_INCRBLOB
  #undef MEM_Zero
  #define MEM_Zero 0x0000
#endif

/*
** Clear any existing type flags from a Mem and replace them with f
*/
#define MemSetTypeFlag(p, f) \
   ((p)->flags = ((p)->flags&~(MEM_TypeMask|MEM_Zero))|f)

/*
** Return true if a memory cell is not marked as invalid.  This macro
** is for use inside assert() statements only.
*/
#ifdef SQLITE_DEBUG
#define memIsValid(M)  ((M)->flags & MEM_Undefined)==0
#endif

/*
** Each auxilliary data pointer stored by a user defined function 
** implementation calling sqlite3_set_auxdata() is stored in an instance
** of this structure. All such structures associated with a single VM
** are stored in a linked list headed at Vdbe.pAuxData. All are destroyed

SQLITE_PRIVATE u32 sqlite3VdbeSerialTypeLen(u32);
SQLITE_PRIVATE u32 sqlite3VdbeSerialType(Mem*, int);
SQLITE_PRIVATE u32 sqlite3VdbeSerialPut(unsigned char*, Mem*, u32);
SQLITE_PRIVATE u32 sqlite3VdbeSerialGet(const unsigned char*, u32, Mem*);
SQLITE_PRIVATE void sqlite3VdbeDeleteAuxData(Vdbe*, int, int);

int sqlite2BtreeKeyCompare(BtCursor *, const void *, int, int, int *);
SQLITE_PRIVATE int sqlite3VdbeIdxKeyCompare(VdbeCursor*,const UnpackedRecord*,int*);
SQLITE_PRIVATE int sqlite3VdbeIdxRowid(sqlite3*, BtCursor *, i64 *);
SQLITE_PRIVATE int sqlite3MemCompare(const Mem*, const Mem*, const CollSeq*);
SQLITE_PRIVATE int sqlite3VdbeExec(Vdbe*);
SQLITE_PRIVATE int sqlite3VdbeList(Vdbe*);
SQLITE_PRIVATE int sqlite3VdbeHalt(Vdbe*);
SQLITE_PRIVATE int sqlite3VdbeChangeEncoding(Mem *, int);
SQLITE_PRIVATE int sqlite3VdbeMemTooBig(Mem*);

SQLITE_PRIVATE double sqlite3VdbeRealValue(Mem*);
SQLITE_PRIVATE void sqlite3VdbeIntegerAffinity(Mem*);
SQLITE_PRIVATE int sqlite3VdbeMemRealify(Mem*);
SQLITE_PRIVATE int sqlite3VdbeMemNumerify(Mem*);
SQLITE_PRIVATE int sqlite3VdbeMemFromBtree(BtCursor*,u32,u32,int,Mem*);
SQLITE_PRIVATE void sqlite3VdbeMemRelease(Mem *p);
SQLITE_PRIVATE void sqlite3VdbeMemReleaseExternal(Mem *p);
#define VdbeMemDynamic(X)  \
  (((X)->flags&(MEM_Agg|MEM_Dyn|MEM_RowSet|MEM_Frame))!=0)
#define VdbeMemRelease(X)  \
  if( VdbeMemDynamic(X) ) sqlite3VdbeMemReleaseExternal(X);
SQLITE_PRIVATE int sqlite3VdbeMemFinalize(Mem*, FuncDef*);
SQLITE_PRIVATE const char *sqlite3OpcodeName(int);
SQLITE_PRIVATE int sqlite3VdbeMemGrow(Mem *pMem, int n, int preserve);
SQLITE_PRIVATE int sqlite3VdbeCloseStatement(Vdbe *, int);
SQLITE_PRIVATE void sqlite3VdbeFrameDelete(VdbeFrame*);
SQLITE_PRIVATE int sqlite3VdbeFrameRestore(VdbeFrame *);

SQLITE_PRIVATE int sqlite3VdbeTransferError(Vdbe *p);

SQLITE_PRIVATE int sqlite3VdbeSorterInit(sqlite3 *, VdbeCursor *);
SQLITE_PRIVATE void sqlite3VdbeSorterClose(sqlite3 *, VdbeCursor *);
SQLITE_PRIVATE int sqlite3VdbeSorterRowkey(const VdbeCursor *, Mem *);
SQLITE_PRIVATE int sqlite3VdbeSorterNext(sqlite3 *, const VdbeCursor *, int *);
SQLITE_PRIVATE int sqlite3VdbeSorterRewind(sqlite3 *, const VdbeCursor *, int *);
SQLITE_PRIVATE int sqlite3VdbeSorterWrite(sqlite3 *, const VdbeCursor *, Mem *);
SQLITE_PRIVATE int sqlite3VdbeSorterCompare(const VdbeCursor *, Mem *, int, int *);

#if !defined(SQLITE_OMIT_SHARED_CACHE) && SQLITE_THREADSAFE>0
SQLITE_PRIVATE   void sqlite3VdbeEnter(Vdbe*);
SQLITE_PRIVATE   void sqlite3VdbeLeave(Vdbe*);
#else
# define sqlite3VdbeEnter(X)
# define sqlite3VdbeLeave(X)
#endif

#ifdef SQLITE_DEBUG
SQLITE_PRIVATE void sqlite3VdbeMemAboutToChange(Vdbe*,Mem*);
SQLITE_PRIVATE int sqlite3VdbeCheckMemInvariants(Mem*);
#endif

#ifndef SQLITE_OMIT_FOREIGN_KEY
SQLITE_PRIVATE int sqlite3VdbeCheckFk(Vdbe *, int);
#else
# define sqlite3VdbeCheckFk(p,i) 0
#endif

  mem5.nAlloc++;
  mem5.totalAlloc += iFullSz;
  mem5.totalExcess += iFullSz - nByte;
  mem5.currentCount++;
  mem5.currentOut += iFullSz;
  if( mem5.maxCount<mem5.currentCount ) mem5.maxCount = mem5.currentCount;
  if( mem5.maxOut<mem5.currentOut ) mem5.maxOut = mem5.currentOut;

#ifdef SQLITE_DEBUG
  /* Make sure the allocated memory does not assume that it is set to zero
  ** or retains a value from a previous allocation */
  memset(&mem5.zPool[i*mem5.szAtom], 0xAA, iFullSz);
#endif

  /* Return a pointer to the allocated memory. */
  return (void*)&mem5.zPool[i*mem5.szAtom];
}

/*
** Free an outstanding memory allocation.

      iBlock = iBuddy;
    }else{
      mem5.aCtrl[iBlock] = CTRL_FREE | iLogsize;
      mem5.aCtrl[iBuddy] = 0;
    }
    size *= 2;
  }

#ifdef SQLITE_DEBUG
  /* Overwrite freed memory with the 0x55 bit pattern to verify that it is
  ** not used after being freed */
  memset(&mem5.zPool[iBlock*mem5.szAtom], 0x55, size);
#endif

  memsys5Link(iBlock, iLogsize);
}

/*
** Allocate nBytes of memory.
*/
static void *memsys5Malloc(int nBytes){

  }
  *z = 0;
  assert( (pMem->n+(desiredEnc==SQLITE_UTF8?1:2))<=len );

  sqlite3VdbeMemRelease(pMem);
  pMem->flags &= ~(MEM_Static|MEM_Dyn|MEM_Ephem);
  pMem->enc = desiredEnc;
  pMem->flags |= (MEM_Term);
  pMem->z = (char*)zOut;
  pMem->zMalloc = pMem->z;

translate_out:
#if defined(TRANSLATE_TRACE) && defined(SQLITE_DEBUG)
  {
    char zBuf[100];

  sqlite3VdbeChangeEncoding(&m, SQLITE_UTF8);
  if( db->mallocFailed ){
    sqlite3VdbeMemRelease(&m);
    m.z = 0;
  }
  assert( (m.flags & MEM_Term)!=0 || db->mallocFailed );
  assert( (m.flags & MEM_Str)!=0 || db->mallocFailed );

  assert( m.z || db->mallocFailed );
  return m.z;
}

/*
** zIn is a UTF-16 encoded unicode string at least nChar characters long.
** Return the number of bytes in the first nChar unicode characters

  i64 iA = *pA;
  testcase( iA==0 ); testcase( iA==1 );
  testcase( iB==-1 ); testcase( iB==0 );
  if( iB>=0 ){
    testcase( iA>0 && LARGEST_INT64 - iA == iB );
    testcase( iA>0 && LARGEST_INT64 - iA == iB - 1 );
    if( iA>0 && LARGEST_INT64 - iA < iB ) return 1;

  }else{
    testcase( iA<0 && -(iA + LARGEST_INT64) == iB + 1 );
    testcase( iA<0 && -(iA + LARGEST_INT64) == iB + 2 );
    if( iA<0 && -(iA + LARGEST_INT64) > iB + 1 ) return 1;

  }
  *pA += iB;
  return 0; 
}
SQLITE_PRIVATE int sqlite3SubInt64(i64 *pA, i64 iB){
  testcase( iB==SMALLEST_INT64+1 );
  if( iB==SMALLEST_INT64 ){
    testcase( (*pA)==(-1) ); testcase( (*pA)==0 );
    if( (*pA)>=0 ) return 1;

  i64 iA = *pA;
  i64 iA1, iA0, iB1, iB0, r;

  iA1 = iA/TWOPOWER32;
  iA0 = iA % TWOPOWER32;
  iB1 = iB/TWOPOWER32;
  iB0 = iB % TWOPOWER32;
  if( iA1==0 ){
    if( iB1==0 ){
      *pA *= iB;
      return 0;
    }
    r = iA0*iB1;
  }else if( iB1==0 ){
    r = iA1*iB0;
  }else{
    /* If both iA1 and iB1 are non-zero, overflow will result */
    return 1;
  }
  testcase( r==(-TWOPOWER31)-1 );
  testcase( r==(-TWOPOWER31) );
  testcase( r==TWOPOWER31 );
  testcase( r==TWOPOWER31-1 );
  if( r<(-TWOPOWER31) || r>=TWOPOWER31 ) return 1;
  r *= TWOPOWER32;
  if( sqlite3AddInt64(&r, iA0*iB0) ) return 1;

     /*  13 */ "Vacuum"           OpHelp(""),
     /*  14 */ "VFilter"          OpHelp("iPlan=r[P3] zPlan='P4'"),
     /*  15 */ "VUpdate"          OpHelp("data=r[P3@P2]"),
     /*  16 */ "Goto"             OpHelp(""),
     /*  17 */ "Gosub"            OpHelp(""),
     /*  18 */ "Return"           OpHelp(""),
     /*  19 */ "Not"              OpHelp("r[P2]= !r[P1]"),
     /*  20 */ "InitCoroutine"    OpHelp(""),
     /*  21 */ "EndCoroutine"     OpHelp(""),
     /*  22 */ "Yield"            OpHelp(""),
     /*  23 */ "HaltIfNull"       OpHelp("if r[P3]=null halt"),
     /*  24 */ "Halt"             OpHelp(""),
     /*  25 */ "Integer"          OpHelp("r[P2]=P1"),
     /*  26 */ "Int64"            OpHelp("r[P2]=P4"),
     /*  27 */ "String"           OpHelp("r[P2]='P4' (len=P1)"),
     /*  28 */ "Null"             OpHelp("r[P2..P3]=NULL"),
     /*  29 */ "SoftNull"         OpHelp("r[P1]=NULL"),
     /*  30 */ "Blob"             OpHelp("r[P2]=P4 (len=P1)"),
     /*  31 */ "Variable"         OpHelp("r[P2]=parameter(P1,P4)"),
     /*  32 */ "Move"             OpHelp("r[P2@P3]=r[P1@P3]"),
     /*  33 */ "Copy"             OpHelp("r[P2@P3+1]=r[P1@P3+1]"),
     /*  34 */ "SCopy"            OpHelp("r[P2]=r[P1]"),
     /*  35 */ "ResultRow"        OpHelp("output=r[P1@P2]"),
     /*  36 */ "CollSeq"          OpHelp(""),
     /*  37 */ "AddImm"           OpHelp("r[P1]=r[P1]+P2"),
     /*  38 */ "MustBeInt"        OpHelp(""),
     /*  39 */ "RealAffinity"     OpHelp(""),
     /*  40 */ "Permutation"      OpHelp(""),
     /*  41 */ "Compare"          OpHelp(""),
     /*  42 */ "Jump"             OpHelp(""),
     /*  43 */ "Once"             OpHelp(""),
     /*  44 */ "If"               OpHelp(""),
     /*  45 */ "IfNot"            OpHelp(""),
     /*  46 */ "Column"           OpHelp("r[P3]=PX"),
     /*  47 */ "Affinity"         OpHelp("affinity(r[P1@P2])"),
     /*  48 */ "MakeRecord"       OpHelp("r[P3]=mkrec(r[P1@P2])"),
     /*  49 */ "Count"            OpHelp("r[P2]=count()"),
     /*  50 */ "ReadCookie"       OpHelp(""),
     /*  51 */ "SetCookie"        OpHelp(""),

     /*  52 */ "OpenRead"         OpHelp("root=P2 iDb=P3"),
     /*  53 */ "OpenWrite"        OpHelp("root=P2 iDb=P3"),
     /*  54 */ "OpenAutoindex"    OpHelp("nColumn=P2"),
     /*  55 */ "OpenEphemeral"    OpHelp("nColumn=P2"),
     /*  56 */ "SorterOpen"       OpHelp(""),
     /*  57 */ "OpenPseudo"       OpHelp("P3 columns in r[P2]"),
     /*  58 */ "Close"            OpHelp(""),
     /*  59 */ "SeekLT"           OpHelp(""),
     /*  60 */ "SeekLE"           OpHelp(""),
     /*  61 */ "SeekGE"           OpHelp(""),
     /*  62 */ "SeekGT"           OpHelp(""),
     /*  63 */ "Seek"             OpHelp("intkey=r[P2]"),
     /*  64 */ "NoConflict"       OpHelp("key=r[P3@P4]"),
     /*  65 */ "NotFound"         OpHelp("key=r[P3@P4]"),
     /*  66 */ "Found"            OpHelp("key=r[P3@P4]"),
     /*  67 */ "NotExists"        OpHelp("intkey=r[P3]"),
     /*  68 */ "Sequence"         OpHelp("r[P2]=rowid"),
     /*  69 */ "NewRowid"         OpHelp("r[P2]=rowid"),
     /*  70 */ "Insert"           OpHelp("intkey=r[P3] data=r[P2]"),


     /*  71 */ "Or"               OpHelp("r[P3]=(r[P1] || r[P2])"),
     /*  72 */ "And"              OpHelp("r[P3]=(r[P1] && r[P2])"),
     /*  73 */ "InsertInt"        OpHelp("intkey=P3 data=r[P2]"),
     /*  74 */ "Delete"           OpHelp(""),
     /*  75 */ "ResetCount"       OpHelp(""),


     /*  76 */ "IsNull"           OpHelp("if r[P1]==NULL goto P2"),
     /*  77 */ "NotNull"          OpHelp("if r[P1]!=NULL goto P2"),
     /*  78 */ "Ne"               OpHelp("if r[P1]!=r[P3] goto P2"),
     /*  79 */ "Eq"               OpHelp("if r[P1]==r[P3] goto P2"),
     /*  80 */ "Gt"               OpHelp("if r[P1]>r[P3] goto P2"),
     /*  81 */ "Le"               OpHelp("if r[P1]<=r[P3] goto P2"),
     /*  82 */ "Lt"               OpHelp("if r[P1]<r[P3] goto P2"),
     /*  83 */ "Ge"               OpHelp("if r[P1]>=r[P3] goto P2"),
     /*  84 */ "SorterCompare"    OpHelp("if key(P1)!=rtrim(r[P3],P4) goto P2"),
     /*  85 */ "BitAnd"           OpHelp("r[P3]=r[P1]&r[P2]"),
     /*  86 */ "BitOr"            OpHelp("r[P3]=r[P1]|r[P2]"),
     /*  87 */ "ShiftLeft"        OpHelp("r[P3]=r[P2]<<r[P1]"),
     /*  88 */ "ShiftRight"       OpHelp("r[P3]=r[P2]>>r[P1]"),
     /*  89 */ "Add"              OpHelp("r[P3]=r[P1]+r[P2]"),
     /*  90 */ "Subtract"         OpHelp("r[P3]=r[P2]-r[P1]"),
     /*  91 */ "Multiply"         OpHelp("r[P3]=r[P1]*r[P2]"),
     /*  92 */ "Divide"           OpHelp("r[P3]=r[P2]/r[P1]"),
     /*  93 */ "Remainder"        OpHelp("r[P3]=r[P2]%r[P1]"),
     /*  94 */ "Concat"           OpHelp("r[P3]=r[P2]+r[P1]"),
     /*  95 */ "SorterData"       OpHelp("r[P2]=data"),
     /*  96 */ "BitNot"           OpHelp("r[P1]= ~r[P1]"),
     /*  97 */ "String8"          OpHelp("r[P2]='P4'"),
     /*  98 */ "RowKey"           OpHelp("r[P2]=key"),
     /*  99 */ "RowData"          OpHelp("r[P2]=data"),
     /* 100 */ "Rowid"            OpHelp("r[P2]=rowid"),
     /* 101 */ "NullRow"          OpHelp(""),
     /* 102 */ "Last"             OpHelp(""),
     /* 103 */ "SorterSort"       OpHelp(""),
     /* 104 */ "Sort"             OpHelp(""),
     /* 105 */ "Rewind"           OpHelp(""),
     /* 106 */ "SorterInsert"     OpHelp(""),
     /* 107 */ "IdxInsert"        OpHelp("key=r[P2]"),
     /* 108 */ "IdxDelete"        OpHelp("key=r[P2@P3]"),
     /* 109 */ "IdxRowid"         OpHelp("r[P2]=rowid"),
     /* 110 */ "IdxLE"            OpHelp("key=r[P3@P4]"),
     /* 111 */ "IdxGT"            OpHelp("key=r[P3@P4]"),
     /* 112 */ "IdxLT"            OpHelp("key=r[P3@P4]"),
     /* 113 */ "IdxGE"            OpHelp("key=r[P3@P4]"),
     /* 114 */ "Destroy"          OpHelp(""),
     /* 115 */ "Clear"            OpHelp(""),
     /* 116 */ "CreateIndex"      OpHelp("r[P2]=root iDb=P1"),
     /* 117 */ "CreateTable"      OpHelp("r[P2]=root iDb=P1"),
     /* 118 */ "ParseSchema"      OpHelp(""),
     /* 119 */ "LoadAnalysis"     OpHelp(""),
     /* 120 */ "DropTable"        OpHelp(""),
     /* 121 */ "DropIndex"        OpHelp(""),
     /* 122 */ "DropTrigger"      OpHelp(""),
     /* 123 */ "IntegrityCk"      OpHelp(""),
     /* 124 */ "RowSetAdd"        OpHelp("rowset(P1)=r[P2]"),
     /* 125 */ "RowSetRead"       OpHelp("r[P3]=rowset(P1)"),
     /* 126 */ "RowSetTest"       OpHelp("if r[P3] in rowset(P1) goto P2"),
     /* 127 */ "Program"          OpHelp(""),
     /* 128 */ "Param"            OpHelp(""),
     /* 129 */ "FkCounter"        OpHelp("fkctr[P1]+=P2"),
     /* 130 */ "FkIfZero"         OpHelp("if fkctr[P1]==0 goto P2"),
     /* 131 */ "MemMax"           OpHelp("r[P1]=max(r[P1],r[P2])"),
     /* 132 */ "IfPos"            OpHelp("if r[P1]>0 goto P2"),




     /* 133 */ "Real"             OpHelp("r[P2]=P4"),
     /* 134 */ "IfNeg"            OpHelp("if r[P1]<0 goto P2"),
     /* 135 */ "IfZero"           OpHelp("r[P1]+=P3, if r[P1]==0 goto P2"),
     /* 136 */ "AggFinal"         OpHelp("accum=r[P1] N=P2"),
     /* 137 */ "IncrVacuum"       OpHelp(""),
     /* 138 */ "Expire"           OpHelp(""),
     /* 139 */ "TableLock"        OpHelp("iDb=P1 root=P2 write=P3"),
     /* 140 */ "VBegin"           OpHelp(""),
     /* 141 */ "VCreate"          OpHelp(""),
     /* 142 */ "VDestroy"         OpHelp(""),




     /* 143 */ "ToText"           OpHelp(""),
     /* 144 */ "ToBlob"           OpHelp(""),
     /* 145 */ "ToNumeric"        OpHelp(""),
     /* 146 */ "ToInt"            OpHelp(""),
     /* 147 */ "ToReal"           OpHelp(""),
     /* 148 */ "VOpen"            OpHelp(""),
     /* 149 */ "VColumn"          OpHelp("r[P3]=vcolumn(P2)"),
     /* 150 */ "VNext"            OpHelp(""),
     /* 151 */ "VRename"          OpHelp(""),
     /* 152 */ "Pagecount"        OpHelp(""),
     /* 153 */ "MaxPgcnt"         OpHelp(""),
     /* 154 */ "Init"             OpHelp("Start at P2"),
     /* 155 */ "Noop"             OpHelp(""),
     /* 156 */ "Explain"          OpHelp(""),
  };
  return azName[i];
}
#endif

/************** End of opcodes.c *********************************************/
/************** Begin file os_unix.c *****************************************/

#  if defined(__RTP__) || defined(_WRS_KERNEL)
#    define OS_VXWORKS 1
#  else
#    define OS_VXWORKS 0
#  endif
#endif



























/*
** standard include files.
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>

/* 
** Windows will only let you create file view mappings
** on allocation size granularity boundaries.
** During sqlite3_os_init() we do a GetSystemInfo()
** to get the granularity size.
*/
static SYSTEM_INFO winSysInfo;

#ifndef SQLITE_OMIT_WAL

/*
** Helper functions to obtain and relinquish the global mutex. The
** global mutex is used to protect the winLockInfo objects used by 
** this file, all of which may be shared by multiple threads.

}

#ifndef SQLITE_OMIT_LOAD_EXTENSION
/*
** Interfaces for opening a shared library, finding entry points
** within the shared library, and closing the shared library.
*/




static void *winDlOpen(sqlite3_vfs *pVfs, const char *zFilename){
  HANDLE h;
  void *zConverted = winConvertFromUtf8Filename(zFilename);
  UNUSED_PARAMETER(pVfs);
  if( zConverted==0 ){
    OSTRACE(("DLOPEN name=%s, handle=%p\n", zFilename, (void*)0));
    return 0;
  }
  if( osIsNT() ){
#if SQLITE_OS_WINRT
    h = osLoadPackagedLibrary((LPCWSTR)zConverted, 0);
#else
    h = osLoadLibraryW((LPCWSTR)zConverted);
#endif
  }
#ifdef SQLITE_WIN32_HAS_ANSI
  else{
    h = osLoadLibraryA((char*)zConverted);
  }
#endif
  OSTRACE(("DLOPEN name=%s, handle=%p\n", zFilename, (void*)h));
  sqlite3_free(zConverted);
  return (void*)h;
}
static void winDlError(sqlite3_vfs *pVfs, int nBuf, char *zBufOut){
  UNUSED_PARAMETER(pVfs);
  winGetLastErrorMsg(osGetLastError(), nBuf, zBufOut);
}
static void (*winDlSym(sqlite3_vfs *pVfs,void *pH,const char *zSym))(void){
  FARPROC proc;
  UNUSED_PARAMETER(pVfs);
  proc = osGetProcAddressA((HANDLE)pH, zSym);
  OSTRACE(("DLSYM handle=%p, symbol=%s, address=%p\n",
           (void*)pH, zSym, (void*)proc));
  return (void(*)(void))proc;
}
static void winDlClose(sqlite3_vfs *pVfs, void *pHandle){
  UNUSED_PARAMETER(pVfs);
  osFreeLibrary((HANDLE)pHandle);
  OSTRACE(("DLCLOSE handle=%p\n", (void*)pHandle));
}
#else /* if SQLITE_OMIT_LOAD_EXTENSION is defined: */
  #define winDlOpen  0
  #define winDlError 0
  #define winDlSym   0
  #define winDlClose 0
#endif

struct PCache {
  PgHdr *pDirty, *pDirtyTail;         /* List of dirty pages in LRU order */
  PgHdr *pSynced;                     /* Last synced page in dirty page list */
  int nRef;                           /* Number of referenced pages */
  int szCache;                        /* Configured cache size */
  int szPage;                         /* Size of every page in this cache */
  int szExtra;                        /* Size of extra space for each page */
  u8 bPurgeable;                      /* True if pages are on backing store */
  u8 eCreate;                         /* eCreate value for for xFetch() */
  int (*xStress)(void*,PgHdr*);       /* Call to try make a page clean */
  void *pStress;                      /* Argument to xStress */
  sqlite3_pcache *pCache;             /* Pluggable cache module */
  PgHdr *pPage1;                      /* Reference to page 1 */
};

/*

    p->pDirtyTail = pPage->pDirtyPrev;
  }
  if( pPage->pDirtyPrev ){
    pPage->pDirtyPrev->pDirtyNext = pPage->pDirtyNext;
  }else{
    assert( pPage==p->pDirty );
    p->pDirty = pPage->pDirtyNext;
    if( p->pDirty==0 && p->bPurgeable ){
      assert( p->eCreate==1 );
      p->eCreate = 2;
    }
  }
  pPage->pDirtyNext = 0;
  pPage->pDirtyPrev = 0;

  expensive_assert( pcacheCheckSynced(p) );
}

/*
** Add page pPage to the head of the dirty list (PCache1.pDirty is set to
** pPage).
*/
static void pcacheAddToDirtyList(PgHdr *pPage){
  PCache *p = pPage->pCache;

  assert( pPage->pDirtyNext==0 && pPage->pDirtyPrev==0 && p->pDirty!=pPage );

  pPage->pDirtyNext = p->pDirty;
  if( pPage->pDirtyNext ){
    assert( pPage->pDirtyNext->pDirtyPrev==0 );
    pPage->pDirtyNext->pDirtyPrev = pPage;
  }else if( p->bPurgeable ){
    assert( p->eCreate==2 );
    p->eCreate = 1;
  }
  p->pDirty = pPage;
  if( !p->pDirtyTail ){
    p->pDirtyTail = pPage;
  }
  if( !p->pSynced && 0==(pPage->flags&PGHDR_NEED_SYNC) ){
    p->pSynced = pPage;

  void *pStress,               /* Argument to xStress */
  PCache *p                    /* Preallocated space for the PCache */
){
  memset(p, 0, sizeof(PCache));
  p->szPage = szPage;
  p->szExtra = szExtra;
  p->bPurgeable = bPurgeable;
  p->eCreate = 2;
  p->xStress = xStress;
  p->pStress = pStress;
  p->szCache = 100;
}

/*
** Change the page size for PCache object. The caller must ensure that there

*/
SQLITE_PRIVATE int sqlite3PcacheFetch(
  PCache *pCache,       /* Obtain the page from this cache */
  Pgno pgno,            /* Page number to obtain */
  int createFlag,       /* If true, create page if it does not exist already */
  PgHdr **ppPage        /* Write the page here */
){
  sqlite3_pcache_page *pPage;
  PgHdr *pPgHdr = 0;
  int eCreate;

  assert( pCache!=0 );
  assert( createFlag==1 || createFlag==0 );
  assert( pgno>0 );

  /* If the pluggable cache (sqlite3_pcache*) has not been allocated,
  ** allocate it now.
  */
  if( !pCache->pCache ){
    sqlite3_pcache *p;
    if( !createFlag ){
      *ppPage = 0;
      return SQLITE_OK;
    }
    p = sqlite3GlobalConfig.pcache2.xCreate(
        pCache->szPage, pCache->szExtra + sizeof(PgHdr), pCache->bPurgeable
    );
    if( !p ){
      return SQLITE_NOMEM;
    }
    sqlite3GlobalConfig.pcache2.xCachesize(p, numberOfCachePages(pCache));
    pCache->pCache = p;
  }

  /* eCreate defines what to do if the page does not exist.
  **    0     Do not allocate a new page.  (createFlag==0)
  **    1     Allocate a new page if doing so is inexpensive.
  **          (createFlag==1 AND bPurgeable AND pDirty)
  **    2     Allocate a new page even it doing so is difficult.
  **          (createFlag==1 AND !(bPurgeable AND pDirty)
  */
  eCreate = createFlag==0 ? 0 : pCache->eCreate;
  assert( (createFlag*(1+(!pCache->bPurgeable||!pCache->pDirty)))==eCreate );
  pPage = sqlite3GlobalConfig.pcache2.xFetch(pCache->pCache, pgno, eCreate);


  if( !pPage && eCreate==1 ){
    PgHdr *pPg;

    /* Find a dirty page to write-out and recycle. First try to find a 
    ** page that does not require a journal-sync (one with PGHDR_NEED_SYNC
    ** cleared), but if that is not possible settle for any other 
    ** unreferenced dirty page.

/*
** Find a page in the hash table given its page number. Return
** a pointer to the page or NULL if the requested page is not 
** already in memory.
*/
static PgHdr *pager_lookup(Pager *pPager, Pgno pgno){
  PgHdr *p = 0;                     /* Return value */

  /* It is not possible for a call to PcacheFetch() with createFlag==0 to
  ** fail, since no attempt to allocate dynamic memory will be made.
  */
  (void)sqlite3PcacheFetch(pPager->pPCache, pgno, 0, &p);
  return p;
}

  }

  if( rc!=SQLITE_OK ){
    walIndexClose(pRet, 0);
    sqlite3OsClose(pRet->pWalFd);
    sqlite3_free(pRet);
  }else{
    int iDC = sqlite3OsDeviceCharacteristics(pDbFd);
    if( iDC & SQLITE_IOCAP_SEQUENTIAL ){ pRet->syncHeader = 0; }
    if( iDC & SQLITE_IOCAP_POWERSAFE_OVERWRITE ){
      pRet->padToSectorBoundary = 0;
    }
    *ppWal = pRet;
    WALTRACE(("WAL%d: opened\n", pRet));
  }

    int iFirstAmt = (int)(p->iSyncPoint - iOffset);
    rc = sqlite3OsWrite(p->pFd, pContent, iFirstAmt, iOffset);
    if( rc ) return rc;
    iOffset += iFirstAmt;
    iAmt -= iFirstAmt;
    pContent = (void*)(iFirstAmt + (char*)pContent);
    assert( p->syncFlags & (SQLITE_SYNC_NORMAL|SQLITE_SYNC_FULL) );
    rc = sqlite3OsSync(p->pFd, p->syncFlags & SQLITE_SYNC_MASK);
    if( iAmt==0 || rc ) return rc;
  }
  rc = sqlite3OsWrite(p->pFd, pContent, iAmt, iOffset);
  return rc;
}

/*

  BtShared *pBt;            /* The BtShared this cursor points to */
  BtCursor *pNext, *pPrev;  /* Forms a linked list of all cursors */
  struct KeyInfo *pKeyInfo; /* Argument passed to comparison function */
#ifndef SQLITE_OMIT_INCRBLOB
  Pgno *aOverflow;          /* Cache of overflow page locations */
#endif
  Pgno pgnoRoot;            /* The root page of this tree */

  CellInfo info;            /* A parse of the cell we are pointing at */
  i64 nKey;        /* Size of pKey, or last integer key */
  void *pKey;      /* Saved key that was cursor's last known position */
  int skipNext;    /* Prev() is noop if negative. Next() is noop if positive */
  u8 wrFlag;                /* True if writable */
  u8 atLast;                /* Cursor pointing to the last entry */
  u8 validNKey;             /* True if info.nKey is valid */

  assert( sqlite3PagerGetData(pPage->pDbPage) == data );
  assert( sqlite3PagerIswriteable(pPage->pDbPage) );
  assert( sqlite3_mutex_held(pBt->mutex) );
  if( pBt->btsFlags & BTS_SECURE_DELETE ){
    memset(&data[hdr], 0, pBt->usableSize - hdr);
  }
  data[hdr] = (char)flags;
  first = hdr + ((flags&PTF_LEAF)==0 ? 12 : 8);
  memset(&data[hdr+1], 0, 4);
  data[hdr+7] = 0;
  put2byte(&data[hdr+5], pBt->usableSize);
  pPage->nFree = (u16)(pBt->usableSize - first);
  decodeFlags(pPage, flags);

  pPage->cellOffset = first;
  pPage->aDataEnd = &data[pBt->usableSize];
  pPage->aCellIdx = &data[first];
  pPage->nOverflow = 0;
  assert( pBt->pageSize>=512 && pBt->pageSize<=65536 );
  pPage->maskPage = (u16)(pBt->pageSize - 1);
  pPage->nCell = 0;

  pCur->wrFlag = (u8)wrFlag;
  pCur->pNext = pBt->pCursor;
  if( pCur->pNext ){
    pCur->pNext->pPrev = pCur;
  }
  pBt->pCursor = pCur;
  pCur->eState = CURSOR_INVALID;

  return SQLITE_OK;
}
SQLITE_PRIVATE int sqlite3BtreeCursor(
  Btree *p,                                   /* The btree */
  int iTable,                                 /* Root page of table to open */
  int wrFlag,                                 /* 1 to write. 0 read-only */
  struct KeyInfo *pKeyInfo,                   /* First arg to xCompare() */

** do not need to be zeroed and they are large, so we can save a lot
** of run-time by skipping the initialization of those elements.
*/
SQLITE_PRIVATE void sqlite3BtreeCursorZero(BtCursor *p){
  memset(p, 0, offsetof(BtCursor, iPage));
}































/*
** Close a cursor.  The read lock on the database file is released
** when the last cursor is closed.
*/
SQLITE_PRIVATE int sqlite3BtreeCloseCursor(BtCursor *pCur){
  Btree *pBtree = pCur->pBtree;
  if( pBtree ){

  BtCursor *pCur,          /* The cursor to be moved */
  UnpackedRecord *pIdxKey, /* Unpacked index key */
  i64 intKey,              /* The table key */
  int biasRight,           /* If true, bias the search to the high end */
  int *pRes                /* Write search results here */
){
  int rc;
  RecordCompare xRecordCompare;

  assert( cursorHoldsMutex(pCur) );
  assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
  assert( pRes );
  assert( (pIdxKey==0)==(pCur->pKeyInfo==0) );

  /* If the cursor is already positioned at the point we are trying
  ** to move to, then just return without doing any work */
  if( pCur->eState==CURSOR_VALID && pCur->validNKey 
   && pCur->apPage[0]->intKey 
  ){
    if( pCur->info.nKey==intKey ){
      *pRes = 0;
      return SQLITE_OK;
    }
    if( pCur->atLast && pCur->info.nKey<intKey ){
      *pRes = -1;
      return SQLITE_OK;
    }
  }

  if( pIdxKey ){
    xRecordCompare = sqlite3VdbeFindCompare(pIdxKey);
    assert( pIdxKey->default_rc==1 
         || pIdxKey->default_rc==0 
         || pIdxKey->default_rc==-1
    );
  }else{
    xRecordCompare = 0; /* Not actually used.  Avoids a compiler warning. */
  }

  rc = moveToRoot(pCur);
  if( rc ){
    return rc;
  }
  assert( pCur->pgnoRoot==0 || pCur->apPage[pCur->iPage] );
  assert( pCur->pgnoRoot==0 || pCur->apPage[pCur->iPage]->isInit );

    assert( pPage->nCell>0 );
    assert( pPage->intKey==(pIdxKey==0) );
    lwr = 0;
    upr = pPage->nCell-1;
    assert( biasRight==0 || biasRight==1 );
    idx = upr>>(1-biasRight); /* idx = biasRight ? upr : (lwr+upr)/2; */
    pCur->aiIdx[pCur->iPage] = (u16)idx;
    if( xRecordCompare==0 ){
      for(;;){
        i64 nCellKey;
        pCell = findCell(pPage, idx) + pPage->childPtrSize;
        if( pPage->hasData ){
          while( 0x80 <= *(pCell++) ){
            if( pCell>=pPage->aDataEnd ) return SQLITE_CORRUPT_BKPT;
          }

        */
        nCell = pCell[0];
        if( nCell<=pPage->max1bytePayload ){
          /* This branch runs if the record-size field of the cell is a
          ** single byte varint and the record fits entirely on the main
          ** b-tree page.  */
          testcase( pCell+nCell+1==pPage->aDataEnd );
          c = xRecordCompare(nCell, (void*)&pCell[1], pIdxKey, 0);
        }else if( !(pCell[1] & 0x80) 
          && (nCell = ((nCell&0x7f)<<7) + pCell[1])<=pPage->maxLocal
        ){
          /* The record-size field is a 2 byte varint and the record 
          ** fits entirely on the main b-tree page.  */
          testcase( pCell+nCell+2==pPage->aDataEnd );
          c = xRecordCompare(nCell, (void*)&pCell[2], pIdxKey, 0);
        }else{
          /* The record flows over onto one or more overflow pages. In
          ** this case the whole cell needs to be parsed, a buffer allocated
          ** and accessPayload() used to retrieve the record into the
          ** buffer before VdbeRecordCompare() can be called. */
          void *pCellKey;
          u8 * const pCellBody = pCell - pPage->childPtrSize;
          btreeParseCellPtr(pPage, pCellBody, &pCur->info);
          nCell = (int)pCur->info.nKey;
          pCellKey = sqlite3Malloc( nCell );
          if( pCellKey==0 ){
            rc = SQLITE_NOMEM;
            goto moveto_finish;
          }
          pCur->aiIdx[pCur->iPage] = (u16)idx;
          rc = accessPayload(pCur, 0, nCell, (unsigned char*)pCellKey, 0);
          if( rc ){
            sqlite3_free(pCellKey);
            goto moveto_finish;
          }
          c = xRecordCompare(nCell, pCellKey, pIdxKey, 0);
          sqlite3_free(pCellKey);
        }
        if( c<0 ){
          lwr = idx+1;
        }else if( c>0 ){
          upr = idx-1;
        }else{

}

/*
** Advance the cursor to the next entry in the database.  If
** successful then set *pRes=0.  If the cursor
** was already pointing to the last entry in the database before
** this routine was called, then set *pRes=1.
**
** The calling function will set *pRes to 0 or 1.  The initial *pRes value
** will be 1 if the cursor being stepped corresponds to an SQL index and
** if this routine could have been skipped if that SQL index had been
** a unique index.  Otherwise the caller will have set *pRes to zero.
** Zero is the common case. The btree implementation is free to use the
** initial *pRes value as a hint to improve performance, but the current
** SQLite btree implementation does not. (Note that the comdb2 btree
** implementation does use this hint, however.)
*/
SQLITE_PRIVATE int sqlite3BtreeNext(BtCursor *pCur, int *pRes){
  int rc;
  int idx;
  MemPage *pPage;

  assert( cursorHoldsMutex(pCur) );
  assert( pRes!=0 );
  assert( *pRes==0 || *pRes==1 );
  assert( pCur->skipNext==0 || pCur->eState!=CURSOR_VALID );
  if( pCur->eState!=CURSOR_VALID ){
    rc = restoreCursorPosition(pCur);
    if( rc!=SQLITE_OK ){
      *pRes = 0;
      return rc;
    }

/*
** Step the cursor to the back to the previous entry in the database.  If
** successful then set *pRes=0.  If the cursor
** was already pointing to the first entry in the database before
** this routine was called, then set *pRes=1.
**
** The calling function will set *pRes to 0 or 1.  The initial *pRes value
** will be 1 if the cursor being stepped corresponds to an SQL index and
** if this routine could have been skipped if that SQL index had been
** a unique index.  Otherwise the caller will have set *pRes to zero.
** Zero is the common case. The btree implementation is free to use the
** initial *pRes value as a hint to improve performance, but the current
** SQLite btree implementation does not. (Note that the comdb2 btree
** implementation does use this hint, however.)
*/
SQLITE_PRIVATE int sqlite3BtreePrevious(BtCursor *pCur, int *pRes){
  int rc;
  MemPage *pPage;

  assert( cursorHoldsMutex(pCur) );
  assert( pRes!=0 );
  assert( *pRes==0 || *pRes==1 );
  assert( pCur->skipNext==0 || pCur->eState!=CURSOR_VALID );
  pCur->atLast = 0;
  if( pCur->eState!=CURSOR_VALID ){
    if( ALWAYS(pCur->eState>=CURSOR_REQUIRESEEK) ){
      rc = btreeRestoreCursorPosition(pCur);
      if( rc!=SQLITE_OK ){
        *pRes = 0;

  ** that the cursor is already where it needs to be and returns without
  ** doing any work. To avoid thwarting these optimizations, it is important
  ** not to clear the cursor here.
  */
  rc = saveAllCursors(pBt, pCur->pgnoRoot, pCur);
  if( rc ) return rc;

  if( pCur->pKeyInfo==0 ){
    /* If this is an insert into a table b-tree, invalidate any incrblob 
    ** cursors open on the row being replaced */


    invalidateIncrblobCursors(p, nKey, 0);

    /* If the cursor is currently on the last row and we are appending a
    ** new row onto the end, set the "loc" to avoid an unnecessary btreeMoveto()
    ** call */
    if( pCur->validNKey && nKey>0 && pCur->info.nKey==nKey-1 ){
      loc = -1;
    }
  }

  if( !loc ){
    rc = btreeMoveto(pCur, pKey, nKey, appendBias, &loc);
    if( rc ) return rc;
  }
  assert( pCur->eState==CURSOR_VALID || (pCur->eState==CURSOR_INVALID && loc) );

  ** is advantageous to leave the cursor pointing to the last entry in
  ** the b-tree if possible. If the cursor is left pointing to the last
  ** entry in the table, and the next row inserted has an integer key
  ** larger than the largest existing key, it is possible to insert the
  ** row without seeking the cursor. This can be a big performance boost.
  */
  pCur->info.nSize = 0;

  if( rc==SQLITE_OK && pPage->nOverflow ){
    pCur->validNKey = 0;
    rc = balance(pCur);

    /* Must make sure nOverflow is reset to zero even if the balance()
    ** fails. Internal data structure corruption will result otherwise. 
    ** Also, set the cursor state to invalid. This stops saveCursorPosition()
    ** from trying to save the current position of the cursor.  */
    pCur->apPage[pCur->iPage]->nOverflow = 0;

  ** the cursor to the largest entry in the tree that is smaller than
  ** the entry being deleted. This cell will replace the cell being deleted
  ** from the internal node. The 'previous' entry is used for this instead
  ** of the 'next' entry, as the previous entry is always a part of the
  ** sub-tree headed by the child page of the cell being deleted. This makes
  ** balancing the tree following the delete operation easier.  */
  if( !pPage->leaf ){
    int notUsed = 0;
    rc = sqlite3BtreePrevious(pCur, &notUsed);
    if( rc ) return rc;
  }

  /* Save the positions of any other cursors open on this table before
  ** making any modifications. Make the page containing the entry to be 
  ** deleted writable. Then free any overflow pages associated with the 

*************************************************************************
**
** This file contains code use to manipulate "Mem" structure.  A "Mem"
** stores a single value in the VDBE.  Mem is an opaque structure visible
** only within the VDBE.  Interface routines refer to a Mem using the
** name sqlite_value
*/

#ifdef SQLITE_DEBUG
/*
** Check invariants on a Mem object.
**
** This routine is intended for use inside of assert() statements, like
** this:    assert( sqlite3VdbeCheckMemInvariants(pMem) );
*/
SQLITE_PRIVATE int sqlite3VdbeCheckMemInvariants(Mem *p){
  /* The MEM_Dyn bit is set if and only if Mem.xDel is a non-NULL destructor
  ** function for Mem.z 
  */
  assert( (p->flags & MEM_Dyn)==0 || p->xDel!=0 );
  assert( (p->flags & MEM_Dyn)!=0 || p->xDel==0 );

  /* If p holds a string or blob, the Mem.z must point to exactly
  ** one of the following:
  **
  **   (1) Memory in Mem.zMalloc and managed by the Mem object
  **   (2) Memory to be freed using Mem.xDel
  **   (3) An ephermal string or blob
  **   (4) A static string or blob
  */
  if( (p->flags & (MEM_Str|MEM_Blob)) && p->z!=0 ){
    assert( 
      ((p->z==p->zMalloc)? 1 : 0) +
      ((p->flags&MEM_Dyn)!=0 ? 1 : 0) +
      ((p->flags&MEM_Ephem)!=0 ? 1 : 0) +
      ((p->flags&MEM_Static)!=0 ? 1 : 0) == 1
    );
  }

  return 1;
}
#endif


/*
** If pMem is an object with a valid string representation, this routine
** ensures the internal encoding for the string representation is
** 'desiredEnc', one of SQLITE_UTF8, SQLITE_UTF16LE or SQLITE_UTF16BE.
**
** If pMem is not a string object, or the encoding of the string

**
** If the bPreserve argument is true, then copy of the content of
** pMem->z into the new allocation.  pMem must be either a string or
** blob if bPreserve is true.  If bPreserve is false, any prior content
** in pMem->z is discarded.
*/
SQLITE_PRIVATE int sqlite3VdbeMemGrow(Mem *pMem, int n, int bPreserve){
  assert( sqlite3VdbeCheckMemInvariants(pMem) );





  assert( (pMem->flags&MEM_RowSet)==0 );

  /* If the bPreserve flag is set to true, then the memory cell must already
  ** contain a valid string or blob value.  */
  assert( bPreserve==0 || pMem->flags&(MEM_Blob|MEM_Str) );
  testcase( bPreserve && pMem->z==0 );

  if( pMem->zMalloc==0 || sqlite3DbMallocSize(pMem->db, pMem->zMalloc)<n ){
    if( n<32 ) n = 32;
    if( bPreserve && pMem->z==pMem->zMalloc ){
      pMem->z = pMem->zMalloc = sqlite3DbReallocOrFree(pMem->db, pMem->z, n);
      bPreserve = 0;
    }else{
      sqlite3DbFree(pMem->db, pMem->zMalloc);
      pMem->zMalloc = sqlite3DbMallocRaw(pMem->db, n);
    }
    if( pMem->zMalloc==0 ){
      VdbeMemRelease(pMem);
      pMem->z = 0;
      pMem->flags = MEM_Null;  
      return SQLITE_NOMEM;
    }
  }

  if( pMem->z && bPreserve && pMem->z!=pMem->zMalloc ){
    memcpy(pMem->zMalloc, pMem->z, pMem->n);
  }
  if( (pMem->flags&MEM_Dyn)!=0 ){
    assert( pMem->xDel!=0 && pMem->xDel!=SQLITE_DYNAMIC );
    pMem->xDel((void *)(pMem->z));
  }

  pMem->z = pMem->zMalloc;
  pMem->flags &= ~(MEM_Dyn|MEM_Ephem|MEM_Static);
  pMem->xDel = 0;
  return SQLITE_OK;
}

/*
** Make the given Mem object MEM_Dyn.  In other words, make it so
** that any TEXT or BLOB content is stored in memory obtained from

*/
SQLITE_PRIVATE void sqlite3VdbeMemReleaseExternal(Mem *p){
  assert( p->db==0 || sqlite3_mutex_held(p->db->mutex) );
  if( p->flags&MEM_Agg ){
    sqlite3VdbeMemFinalize(p, p->u.pDef);
    assert( (p->flags & MEM_Agg)==0 );
    sqlite3VdbeMemRelease(p);
  }else if( p->flags&MEM_Dyn ){
    assert( (p->flags&MEM_RowSet)==0 );
    assert( p->xDel!=SQLITE_DYNAMIC && p->xDel!=0 );
    p->xDel((void *)p->z);
    p->xDel = 0;
  }else if( p->flags&MEM_RowSet ){
    sqlite3RowSetClear(p->u.pRowSet);
  }else if( p->flags&MEM_Frame ){
    sqlite3VdbeMemSetNull(p);
  }
}

/*
** Release any memory held by the Mem. This may leave the Mem in an
** inconsistent state, for example with (Mem.z==0) and
** (Mem.flags==MEM_Str).
*/
SQLITE_PRIVATE void sqlite3VdbeMemRelease(Mem *p){
  assert( sqlite3VdbeCheckMemInvariants(p) );
  VdbeMemRelease(p);
  if( p->zMalloc ){
    sqlite3DbFree(p->db, p->zMalloc);
    p->zMalloc = 0;
  }
  p->z = 0;
  assert( p->xDel==0 );  /* Zeroed by VdbeMemRelease() above */

    pFrame->pParent = pFrame->v->pDelFrame;
    pFrame->v->pDelFrame = pFrame;
  }
  if( pMem->flags & MEM_RowSet ){
    sqlite3RowSetClear(pMem->u.pRowSet);
  }
  MemSetTypeFlag(pMem, MEM_Null);

}
SQLITE_PRIVATE void sqlite3ValueSetNull(sqlite3_value *p){
  sqlite3VdbeMemSetNull((Mem*)p); 
}

/*
** Delete any previous value and set the value to be a BLOB of length
** n containing all zeros.
*/
SQLITE_PRIVATE void sqlite3VdbeMemSetZeroBlob(Mem *pMem, int n){
  sqlite3VdbeMemRelease(pMem);
  pMem->flags = MEM_Blob|MEM_Zero;

  pMem->n = 0;
  if( n<0 ) n = 0;
  pMem->u.nZero = n;
  pMem->enc = SQLITE_UTF8;

#ifdef SQLITE_OMIT_INCRBLOB
  sqlite3VdbeMemGrow(pMem, n, 0);

** Delete any previous value and set the value stored in *pMem to val,
** manifest type INTEGER.
*/
SQLITE_PRIVATE void sqlite3VdbeMemSetInt64(Mem *pMem, i64 val){
  sqlite3VdbeMemRelease(pMem);
  pMem->u.i = val;
  pMem->flags = MEM_Int;

}

#ifndef SQLITE_OMIT_FLOATING_POINT
/*
** Delete any previous value and set the value stored in *pMem to val,
** manifest type REAL.
*/
SQLITE_PRIVATE void sqlite3VdbeMemSetDouble(Mem *pMem, double val){
  if( sqlite3IsNaN(val) ){
    sqlite3VdbeMemSetNull(pMem);
  }else{
    sqlite3VdbeMemRelease(pMem);
    pMem->r = val;
    pMem->flags = MEM_Real;

  }
}
#endif

/*
** Delete any previous value and set the value of pMem to be an
** empty boolean index.

** copies are not misused.
*/
SQLITE_PRIVATE void sqlite3VdbeMemAboutToChange(Vdbe *pVdbe, Mem *pMem){
  int i;
  Mem *pX;
  for(i=1, pX=&pVdbe->aMem[1]; i<=pVdbe->nMem; i++, pX++){
    if( pX->pScopyFrom==pMem ){
      pX->flags |= MEM_Undefined;
      pX->pScopyFrom = 0;
    }
  }
  pMem->pScopyFrom = 0;
}
#endif /* SQLITE_DEBUG */

SQLITE_PRIVATE int sqlite3VdbeMemCopy(Mem *pTo, const Mem *pFrom){
  int rc = SQLITE_OK;

  assert( (pFrom->flags & MEM_RowSet)==0 );
  VdbeMemRelease(pTo);
  memcpy(pTo, pFrom, MEMCELLSIZE);
  pTo->flags &= ~MEM_Dyn;
  pTo->xDel = 0;

  if( pTo->flags&(MEM_Str|MEM_Blob) ){
    if( 0==(pFrom->flags&MEM_Static) ){
      pTo->flags |= MEM_Ephem;
      rc = sqlite3VdbeMemMakeWriteable(pTo);
    }
  }

    pMem->xDel = xDel;
    flags |= ((xDel==SQLITE_STATIC)?MEM_Static:MEM_Dyn);
  }

  pMem->n = nByte;
  pMem->flags = flags;
  pMem->enc = (enc==0 ? SQLITE_UTF8 : enc);


#ifndef SQLITE_OMIT_UTF16
  if( pMem->enc!=SQLITE_UTF8 && sqlite3VdbeMemHandleBom(pMem) ){
    return SQLITE_NOMEM;
  }
#endif

  if( nByte>iLimit ){
    return SQLITE_TOOBIG;
  }

  return SQLITE_OK;
}


















































































































/*
** Move data out of a btree key or data field and into a Mem structure.
** The data or key is taken from the entry that pCur is currently pointing
** to.  offset and amt determine what portion of the data or key to retrieve.
** key is true to get the key or false to get data.  The result is written
** into the pMem element.
**

  }
  assert( zData!=0 );

  if( offset+amt<=available ){
    sqlite3VdbeMemRelease(pMem);
    pMem->z = &zData[offset];
    pMem->flags = MEM_Blob|MEM_Ephem;
    pMem->n = (int)amt;
  }else if( SQLITE_OK==(rc = sqlite3VdbeMemGrow(pMem, amt+2, 0)) ){



    if( key ){
      rc = sqlite3BtreeKey(pCur, offset, amt, pMem->z);
    }else{
      rc = sqlite3BtreeData(pCur, offset, amt, pMem->z);
    }
    if( rc==SQLITE_OK ){
      pMem->z[amt] = 0;
      pMem->z[amt+1] = 0;

      pMem->flags = MEM_Blob|MEM_Term;
      pMem->n = (int)amt;
    }else{
      sqlite3VdbeMemRelease(pMem);
    }
  }


  return rc;
}

/* This function is only available internally, it is not part of the
** external API. It works in a similar way to sqlite3_value_text(),
** except the data returned is in the encoding specified by the second

/*
** Create a new sqlite3_value object.
*/
SQLITE_PRIVATE sqlite3_value *sqlite3ValueNew(sqlite3 *db){
  Mem *p = sqlite3DbMallocZero(db, sizeof(*p));
  if( p ){
    p->flags = MEM_Null;

    p->db = db;
  }
  return p;
}

/*
** Context object passed by sqlite3Stat4ProbeSetValue() through to 

      nByte = sizeof(Mem) * nCol + ROUND8(sizeof(UnpackedRecord));
      pRec = (UnpackedRecord*)sqlite3DbMallocZero(db, nByte);
      if( pRec ){
        pRec->pKeyInfo = sqlite3KeyInfoOfIndex(p->pParse, pIdx);
        if( pRec->pKeyInfo ){
          assert( pRec->pKeyInfo->nField+pRec->pKeyInfo->nXField==nCol );
          assert( pRec->pKeyInfo->enc==ENC(db) );

          pRec->aMem = (Mem *)((u8*)pRec + ROUND8(sizeof(UnpackedRecord)));
          for(i=0; i<nCol; i++){
            pRec->aMem[i].flags = MEM_Null;

            pRec->aMem[i].db = db;
          }
        }else{
          sqlite3DbFree(db, pRec);
          pRec = 0;
        }
      }

    if( pVal==0 ) goto no_mem;
    if( ExprHasProperty(pExpr, EP_IntValue) ){
      sqlite3VdbeMemSetInt64(pVal, (i64)pExpr->u.iValue*negInt);
    }else{
      zVal = sqlite3MPrintf(db, "%s%s", zNeg, pExpr->u.zToken);
      if( zVal==0 ) goto no_mem;
      sqlite3ValueSetStr(pVal, -1, zVal, SQLITE_UTF8, SQLITE_DYNAMIC);

    }
    if( (op==TK_INTEGER || op==TK_FLOAT ) && affinity==SQLITE_AFF_NONE ){
      sqlite3ValueApplyAffinity(pVal, SQLITE_AFF_NUMERIC, SQLITE_UTF8);
    }else{
      sqlite3ValueApplyAffinity(pVal, affinity, SQLITE_UTF8);
    }
    if( pVal->flags & (MEM_Int|MEM_Real) ) pVal->flags &= ~MEM_Str;
    if( enc!=SQLITE_UTF8 ){
      rc = sqlite3VdbeChangeEncoding(pVal, enc);
    }
  }else if( op==TK_UMINUS ) {
    /* This branch happens for multiple negative signs.  Ex: -(-5) */
    if( SQLITE_OK==sqlite3ValueFromExpr(db,pExpr->pLeft,enc,affinity,&pVal) 
     && pVal!=0
    ){
      sqlite3VdbeMemNumerify(pVal);
      if( pVal->u.i==SMALLEST_INT64 ){
        pVal->flags &= ~MEM_Int;
        pVal->flags |= MEM_Real;
        pVal->r = (double)SMALLEST_INT64;
      }else{
        pVal->u.i = -pVal->u.i;
      }
      pVal->r = -pVal->r;
      sqlite3ValueApplyAffinity(pVal, affinity, enc);
    }
  }else if( op==TK_NULL ){

    nVal = sqlite3Strlen30(zVal)-1;
    assert( zVal[nVal]=='\'' );
    sqlite3VdbeMemSetStr(pVal, sqlite3HexToBlob(db, zVal, nVal), nVal/2,
                         0, SQLITE_DYNAMIC);
  }
#endif




  *ppVal = pVal;
  return rc;

no_mem:
  db->mallocFailed = 1;
  sqlite3DbFree(db, zVal);
  assert( *ppVal==0 );

      pVal = valueNew(db, &alloc);
      if( pVal ){
        rc = sqlite3VdbeMemCopy((Mem*)pVal, &v->aVar[iBindVar-1]);
        if( rc==SQLITE_OK ){
          sqlite3ValueApplyAffinity(pVal, affinity, ENC(db));
        }
        pVal->db = pParse->db;

      }
    }
  }else{
    rc = valueFromExpr(db, pExpr, ENC(db), affinity, &pVal, &alloc);
  }
  *pbOk = (pVal!=0);

    sqlite3VdbePrintOp(0, i, &p->aOp[i]);
    test_addop_breakpoint();
  }
#endif
#ifdef VDBE_PROFILE
  pOp->cycles = 0;
  pOp->cnt = 0;
#endif
#ifdef SQLITE_VDBE_COVERAGE
  pOp->iSrcLine = 0;
#endif
  return i;
}
SQLITE_PRIVATE int sqlite3VdbeAddOp0(Vdbe *p, int op){
  return sqlite3VdbeAddOp3(p, op, 0, 0, 0);
}
SQLITE_PRIVATE int sqlite3VdbeAddOp1(Vdbe *p, int op, int p1){

  return aOp;
}

/*
** Add a whole list of operations to the operation stack.  Return the
** address of the first operation added.
*/
SQLITE_PRIVATE int sqlite3VdbeAddOpList(Vdbe *p, int nOp, VdbeOpList const *aOp, int iLineno){
  int addr;
  assert( p->magic==VDBE_MAGIC_INIT );
  if( p->nOp + nOp > p->pParse->nOpAlloc && growOpArray(p) ){
    return 0;
  }
  addr = p->nOp;
  if( ALWAYS(nOp>0) ){

      }
      pOut->p3 = pIn->p3;
      pOut->p4type = P4_NOTUSED;
      pOut->p4.p = 0;
      pOut->p5 = 0;
#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
      pOut->zComment = 0;
#endif
#ifdef SQLITE_VDBE_COVERAGE
      pOut->iSrcLine = iLineno+i;
#else
      (void)iLineno;
#endif
#ifdef SQLITE_DEBUG
      if( p->db->flags & SQLITE_VdbeAddopTrace ){
        sqlite3VdbePrintOp(0, i+addr, &p->aOp[i+addr]);
      }
#endif
    }

    va_start(ap, zFormat);
    vdbeVComment(p, zFormat, ap);
    va_end(ap);
  }
}
#endif  /* NDEBUG */

#ifdef SQLITE_VDBE_COVERAGE
/*
** Set the value if the iSrcLine field for the previously coded instruction.
*/
SQLITE_PRIVATE void sqlite3VdbeSetLineNumber(Vdbe *v, int iLine){
  sqlite3VdbeGetOp(v,-1)->iSrcLine = iLine;
}
#endif /* SQLITE_VDBE_COVERAGE */

/*
** Return the opcode for a given address.  If the address is -1, then
** return the most recently inserted opcode.
**
** If a memory allocation error has occurred prior to the calling of this
** routine, then a pointer to a dummy VdbeOp will be returned.  That opcode
** is readable but not writable, though it is cast to a writable value.
** The return of a dummy opcode allows the call to continue functioning
** after a OOM fault without having to check to see if the return from 
** this routine is a valid pointer.  But because the dummy.opcode is 0,
** dummy will never be written to.  This is verified by code inspection and
** by running with Valgrind.








*/
SQLITE_PRIVATE VdbeOp *sqlite3VdbeGetOp(Vdbe *p, int addr){
  /* C89 specifies that the constant "dummy" will be initialized to all
  ** zeros, which is correct.  MSVC generates a warning, nevertheless. */
  static VdbeOp dummy;  /* Ignore the MSVC warning about no initializer */
  assert( p->magic==VDBE_MAGIC_INIT );
  if( addr<0 ){



    addr = p->nOp - 1;
  }
  assert( (addr>=0 && addr<p->nOp) || p->db->mallocFailed );
  if( p->db->mallocFailed ){
    return (VdbeOp*)&dummy;
  }else{
    return &p->aOp[addr];

  char zCom[100];
  static const char *zFormat1 = "%4d %-13s %4d %4d %4d %-13s %.2X %s\n";
  if( pOut==0 ) pOut = stdout;
  zP4 = displayP4(pOp, zPtr, sizeof(zPtr));
#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
  displayComment(pOp, zP4, zCom, sizeof(zCom));
#else
  zCom[0] = 0;
#endif
  /* NB:  The sqlite3OpcodeName() function is implemented by code created
  ** by the mkopcodeh.awk and mkopcodec.awk scripts which extract the
  ** information from the vdbe.c source text */
  fprintf(pOut, zFormat1, pc, 
      sqlite3OpcodeName(pOp->opcode), pOp->p1, pOp->p2, pOp->p3, zP4, pOp->p5,
      zCom

      for(pEnd=&p[N]; p<pEnd; p++){
        sqlite3DbFree(db, p->zMalloc);
      }
      return;
    }
    for(pEnd=&p[N]; p<pEnd; p++){
      assert( (&p[1])==pEnd || p[0].db==p[1].db );
      assert( sqlite3VdbeCheckMemInvariants(p) );

      /* This block is really an inlined version of sqlite3VdbeMemRelease()
      ** that takes advantage of the fact that the memory cell value is 
      ** being set to NULL after releasing any dynamic resources.
      **
      ** The justification for duplicating code is that according to 
      ** callgrind, this causes a certain test case to hit the CPU 4.7 
      ** percent less (x86 linux, gcc version 4.1.2, -O6) than if 
      ** sqlite3MemRelease() were called from here. With -O2, this jumps
      ** to 6.6 percent. The test case is inserting 1000 rows into a table 
      ** with no indexes using a single prepared INSERT statement, bind() 
      ** and reset(). Inserts are grouped into a transaction.
      */
      if( p->flags&(MEM_Agg|MEM_Dyn|MEM_Frame|MEM_RowSet) ){
        sqlite3VdbeMemRelease(p);
      }else if( p->zMalloc ){
        sqlite3DbFree(db, p->zMalloc);
        p->zMalloc = 0;
      }

      p->flags = MEM_Undefined;
    }
    db->mallocFailed = malloc_failed;
  }
}

/*
** Delete a VdbeFrame object and its contents. VdbeFrame objects are

      for(j=0; i>=apSub[j]->nOp; j++){
        i -= apSub[j]->nOp;
      }
      pOp = &apSub[j]->aOp[i];
    }
    if( p->explain==1 ){
      pMem->flags = MEM_Int;

      pMem->u.i = i;                                /* Program counter */
      pMem++;
  
      pMem->flags = MEM_Static|MEM_Str|MEM_Term;
      pMem->z = (char*)sqlite3OpcodeName(pOp->opcode); /* Opcode */
      assert( pMem->z!=0 );
      pMem->n = sqlite3Strlen30(pMem->z);

      pMem->enc = SQLITE_UTF8;
      pMem++;

      /* When an OP_Program opcode is encounter (the only opcode that has
      ** a P4_SUBPROGRAM argument), expand the size of the array of subprograms
      ** kept in p->aMem[9].z to hold the new program - assuming this subprogram
      ** has not already been seen.

          pSub->n = nSub*sizeof(SubProgram*);
        }
      }
    }

    pMem->flags = MEM_Int;
    pMem->u.i = pOp->p1;                          /* P1 */

    pMem++;

    pMem->flags = MEM_Int;
    pMem->u.i = pOp->p2;                          /* P2 */

    pMem++;

    pMem->flags = MEM_Int;
    pMem->u.i = pOp->p3;                          /* P3 */

    pMem++;

    if( sqlite3VdbeMemGrow(pMem, 32, 0) ){            /* P4 */
      assert( p->db->mallocFailed );
      return SQLITE_ERROR;
    }
    pMem->flags = MEM_Str|MEM_Term;
    zP4 = displayP4(pOp, pMem->z, 32);
    if( zP4!=pMem->z ){
      sqlite3VdbeMemSetStr(pMem, zP4, -1, SQLITE_UTF8, 0);
    }else{
      assert( pMem->z!=0 );
      pMem->n = sqlite3Strlen30(pMem->z);
      pMem->enc = SQLITE_UTF8;
    }

    pMem++;

    if( p->explain==1 ){
      if( sqlite3VdbeMemGrow(pMem, 4, 0) ){
        assert( p->db->mallocFailed );
        return SQLITE_ERROR;
      }
      pMem->flags = MEM_Str|MEM_Term;
      pMem->n = 2;
      sqlite3_snprintf(3, pMem->z, "%.2x", pOp->p5);   /* P5 */

      pMem->enc = SQLITE_UTF8;
      pMem++;
  
#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
      if( sqlite3VdbeMemGrow(pMem, 500, 0) ){
        assert( p->db->mallocFailed );
        return SQLITE_ERROR;
      }
      pMem->flags = MEM_Str|MEM_Term;
      pMem->n = displayComment(pOp, zP4, pMem->z, 500);

      pMem->enc = SQLITE_UTF8;
#else
      pMem->flags = MEM_Null;                       /* Comment */

#endif
    }

    p->nResColumn = 8 - 4*(p->explain-1);
    p->pResultSet = &p->aMem[1];
    p->rc = SQLITE_OK;
    rc = SQLITE_ROW;

*/
SQLITE_PRIVATE void sqlite3VdbePrintSql(Vdbe *p){
  const char *z = 0;
  if( p->zSql ){
    z = p->zSql;
  }else if( p->nOp>=1 ){
    const VdbeOp *pOp = &p->aOp[0];
    if( pOp->opcode==OP_Init && pOp->p4.z!=0 ){
      z = pOp->p4.z;
      while( sqlite3Isspace(*z) ) z++;
    }
  }
  if( z ) printf("SQL: [%s]\n", z);
}
#endif

#if !defined(SQLITE_OMIT_TRACE) && defined(SQLITE_ENABLE_IOTRACE)
/*
** Print an IOTRACE message showing SQL content.
*/
SQLITE_PRIVATE void sqlite3VdbeIOTraceSql(Vdbe *p){
  int nOp = p->nOp;
  VdbeOp *pOp;
  if( sqlite3IoTrace==0 ) return;
  if( nOp<1 ) return;
  pOp = &p->aOp[0];
  if( pOp->opcode==OP_Init && pOp->p4.z!=0 ){
    int i, j;
    char z[1000];
    sqlite3_snprintf(sizeof(z), z, "%s", pOp->p4.z);
    for(i=0; sqlite3Isspace(z[i]); i++){}
    for(j=0; z[i]; i++){
      if( sqlite3Isspace(z[i]) ){
        if( z[i-1]!=' ' ){

    memcpy(p->azVar, pParse->azVar, p->nzVar*sizeof(p->azVar[0]));
    memset(pParse->azVar, 0, pParse->nzVar*sizeof(pParse->azVar[0]));
  }
  if( p->aMem ){
    p->aMem--;                      /* aMem[] goes from 1..nMem */
    p->nMem = nMem;                 /*       not from 0..nMem-1 */
    for(n=1; n<=nMem; n++){
      p->aMem[n].flags = MEM_Undefined;
      p->aMem[n].db = db;
    }
  }
  p->explain = pParse->explain;
  sqlite3VdbeRewind(p);
}

#ifdef SQLITE_DEBUG
  /* Execute assert() statements to ensure that the Vdbe.apCsr[] and 
  ** Vdbe.aMem[] arrays have already been cleaned up.  */
  int i;
  if( p->apCsr ) for(i=0; i<p->nCursor; i++) assert( p->apCsr[i]==0 );
  if( p->aMem ){
    for(i=1; i<=p->nMem; i++) assert( p->aMem[i].flags==MEM_Undefined );
  }
#endif

  sqlite3DbFree(db, p->zErrMsg);
  p->zErrMsg = 0;
  p->pResultSet = 0;
}

    if( out ){
      int i;
      fprintf(out, "---- ");
      for(i=0; i<p->nOp; i++){
        fprintf(out, "%02x", p->aOp[i].opcode);
      }
      fprintf(out, "\n");
      if( p->zSql ){
        char c, pc = 0;
        fprintf(out, "-- ");
        for(i=0; (c = p->zSql[i])!=0; i++){
          if( pc=='\n' ) fprintf(out, "-- ");
          putc(c, out);
          pc = c;
        }
        if( pc!='\n' ) fprintf(out, "\n");
      }
      for(i=0; i<p->nOp; i++){
        char zHdr[100];
        sqlite3_snprintf(sizeof(zHdr), zHdr, "%6u %12llu %8llu ",
           p->aOp[i].cnt,
           p->aOp[i].cycles,
           p->aOp[i].cnt>0 ? p->aOp[i].cycles/p->aOp[i].cnt : 0
        );
        fprintf(out, "%s", zHdr);
        sqlite3VdbePrintOp(out, i, &p->aOp[i]);
      }
      fclose(out);
    }
  }
#endif
  p->iCurrentTime = 0;

    return len;
  }

  /* NULL or constants 0 or 1 */
  return 0;
}

/* Input "x" is a sequence of unsigned characters that represent a
** big-endian integer.  Return the equivalent native integer
*/
#define ONE_BYTE_INT(x)    ((i8)(x)[0])
#define TWO_BYTE_INT(x)    (256*(i8)((x)[0])|(x)[1])
#define THREE_BYTE_INT(x)  (65536*(i8)((x)[0])|((x)[1]<<8)|(x)[2])
#define FOUR_BYTE_UINT(x)  (((u32)(x)[0]<<24)|((x)[1]<<16)|((x)[2]<<8)|(x)[3])

/*
** Deserialize the data blob pointed to by buf as serial type serial_type
** and store the result in pMem.  Return the number of bytes read.
*/ 
SQLITE_PRIVATE u32 sqlite3VdbeSerialGet(
  const unsigned char *buf,     /* Buffer to deserialize from */
  u32 serial_type,              /* Serial type to deserialize */
  Mem *pMem                     /* Memory cell to write value into */
){
  u64 x;
  u32 y;

  switch( serial_type ){
    case 10:   /* Reserved for future use */
    case 11:   /* Reserved for future use */
    case 0: {  /* NULL */
      pMem->flags = MEM_Null;
      break;
    }
    case 1: { /* 1-byte signed integer */
      pMem->u.i = ONE_BYTE_INT(buf);
      pMem->flags = MEM_Int;
      return 1;
    }
    case 2: { /* 2-byte signed integer */

      pMem->u.i = TWO_BYTE_INT(buf);
      pMem->flags = MEM_Int;
      return 2;
    }
    case 3: { /* 3-byte signed integer */

      pMem->u.i = THREE_BYTE_INT(buf);
      pMem->flags = MEM_Int;
      return 3;
    }
    case 4: { /* 4-byte signed integer */
      y = FOUR_BYTE_UINT(buf);
      pMem->u.i = (i64)*(int*)&y;
      pMem->flags = MEM_Int;
      return 4;
    }
    case 5: { /* 6-byte signed integer */



      pMem->u.i = FOUR_BYTE_UINT(buf+2) + (((i64)1)<<32)*TWO_BYTE_INT(buf);
      pMem->flags = MEM_Int;
      return 6;
    }
    case 6:   /* 8-byte signed integer */
    case 7: { /* IEEE floating point */
#if !defined(NDEBUG) && !defined(SQLITE_OMIT_FLOATING_POINT)
      /* Verify that integers and floating point values use the same
      ** byte order.  Or, that if SQLITE_MIXED_ENDIAN_64BIT_FLOAT is
      ** defined that 64-bit floating point values really are mixed
      ** endian.
      */
      static const u64 t1 = ((u64)0x3ff00000)<<32;
      static const double r1 = 1.0;
      u64 t2 = t1;
      swapMixedEndianFloat(t2);
      assert( sizeof(r1)==sizeof(t2) && memcmp(&r1, &t2, sizeof(r1))==0 );
#endif
      x = FOUR_BYTE_UINT(buf);
      y = FOUR_BYTE_UINT(buf+4);
      x = (x<<32) | y;
      if( serial_type==6 ){
        pMem->u.i = *(i64*)&x;
        pMem->flags = MEM_Int;
      }else{
        assert( sizeof(x)==8 && sizeof(pMem->r)==8 );
        swapMixedEndianFloat(x);

  const unsigned char *aKey = (const unsigned char *)pKey;
  int d; 
  u32 idx;                        /* Offset in aKey[] to read from */
  u16 u;                          /* Unsigned loop counter */
  u32 szHdr;
  Mem *pMem = p->aMem;

  p->default_rc = 0;
  assert( EIGHT_BYTE_ALIGNMENT(pMem) );
  idx = getVarint32(aKey, szHdr);
  d = szHdr;
  u = 0;
  while( idx<szHdr && u<p->nField && d<=nKey ){
    u32 serial_type;

    idx += getVarint32(&aKey[idx], serial_type);
    pMem->enc = pKeyInfo->enc;
    pMem->db = pKeyInfo->db;
    /* pMem->flags = 0; // sqlite3VdbeSerialGet() will set this for us */
    pMem->zMalloc = 0;
    d += sqlite3VdbeSerialGet(&aKey[d], serial_type, pMem);
    pMem++;
    u++;
  }
  assert( u<=pKeyInfo->nField + 1 );
  p->nField = u;
}

#if SQLITE_DEBUG
/*
** This function compares two index or table record keys in the same way

** as the sqlite3VdbeRecordCompare() routine. Unlike VdbeRecordCompare(),
** this function deserializes and compares values using the
** sqlite3VdbeSerialGet() and sqlite3MemCompare() functions. It is used
** in assert() statements to ensure that the optimized code in
** sqlite3VdbeRecordCompare() returns results with these two primitives.








*/
static int vdbeRecordCompareDebug(
  int nKey1, const void *pKey1, /* Left key */
  const UnpackedRecord *pPKey2  /* Right key */
){
  u32 d1;            /* Offset into aKey[] of next data element */
  u32 idx1;          /* Offset into aKey[] of next header element */
  u32 szHdr1;        /* Number of bytes in header */
  int i = 0;
  int rc = 0;
  const unsigned char *aKey1 = (const unsigned char *)pKey1;

  /* No memory allocation is ever used on mem1.  Prove this using
  ** the following assert().  If the assert() fails, it indicates a
  ** memory leak and a need to call sqlite3VdbeMemRelease(&mem1).
  */
  assert( mem1.zMalloc==0 );

  /* rc==0 here means that one of the keys ran out of fields and
  ** all the fields up to that point were equal. Return the the default_rc
  ** value.  */
  return pPKey2->default_rc;
}
#endif

/*
** Both *pMem1 and *pMem2 contain string values. Compare the two values
** using the collation sequence pColl. As usual, return a negative , zero
** or positive value if *pMem1 is less than, equal to or greater than 
** *pMem2, respectively. Similar in spirit to "rc = (*pMem1) - (*pMem2);".
*/
static int vdbeCompareMemString(
  const Mem *pMem1,
  const Mem *pMem2,
  const CollSeq *pColl
){
  if( pMem1->enc==pColl->enc ){
    /* The strings are already in the correct encoding.  Call the
     ** comparison function directly */
    return pColl->xCmp(pColl->pUser,pMem1->n,pMem1->z,pMem2->n,pMem2->z);
  }else{
    int rc;
    const void *v1, *v2;
    int n1, n2;
    Mem c1;
    Mem c2;
    memset(&c1, 0, sizeof(c1));
    memset(&c2, 0, sizeof(c2));
    sqlite3VdbeMemShallowCopy(&c1, pMem1, MEM_Ephem);
    sqlite3VdbeMemShallowCopy(&c2, pMem2, MEM_Ephem);
    v1 = sqlite3ValueText((sqlite3_value*)&c1, pColl->enc);
    n1 = v1==0 ? 0 : c1.n;
    v2 = sqlite3ValueText((sqlite3_value*)&c2, pColl->enc);
    n2 = v2==0 ? 0 : c2.n;
    rc = pColl->xCmp(pColl->pUser, n1, v1, n2, v2);
    sqlite3VdbeMemRelease(&c1);
    sqlite3VdbeMemRelease(&c2);
    return rc;
  }
}

/*
** Compare the values contained by the two memory cells, returning
** negative, zero or positive if pMem1 is less than, equal to, or greater
** than pMem2. Sorting order is NULL's first, followed by numbers (integers
** and reals) sorted numerically, followed by text ordered by the collating
** sequence pColl and finally blob's ordered by memcmp().
**
** Two NULL values are considered equal by this function.
*/
SQLITE_PRIVATE int sqlite3MemCompare(const Mem *pMem1, const Mem *pMem2, const CollSeq *pColl){
  int rc;
  int f1, f2;
  int combined_flags;

  f1 = pMem1->flags;
  f2 = pMem2->flags;
  combined_flags = f1|f2;
  assert( (combined_flags & MEM_RowSet)==0 );
 
  /* If one value is NULL, it is less than the other. If both values
  ** are NULL, return 0.
  */
  if( combined_flags&MEM_Null ){
    return (f2&MEM_Null) - (f1&MEM_Null);
  }

  /* If one value is a number and the other is not, the number is less.
  ** If both are numbers, compare as reals if one is a real, or as integers
  ** if both values are integers.
  */
  if( combined_flags&(MEM_Int|MEM_Real) ){
    double r1, r2;
    if( (f1 & f2 & MEM_Int)!=0 ){
      if( pMem1->u.i < pMem2->u.i ) return -1;
      if( pMem1->u.i > pMem2->u.i ) return 1;
      return 0;
    }
    if( (f1&MEM_Real)!=0 ){
      r1 = pMem1->r;
    }else if( (f1&MEM_Int)!=0 ){
      r1 = (double)pMem1->u.i;
    }else{
      return 1;
    }
    if( (f2&MEM_Real)!=0 ){
      r2 = pMem2->r;
    }else if( (f2&MEM_Int)!=0 ){
      r2 = (double)pMem2->u.i;
    }else{
      return -1;
    }
    if( r1<r2 ) return -1;
    if( r1>r2 ) return 1;
    return 0;
  }

  /* If one value is a string and the other is a blob, the string is less.
  ** If both are strings, compare using the collating functions.
  */
  if( combined_flags&MEM_Str ){
    if( (f1 & MEM_Str)==0 ){
      return 1;
    }
    if( (f2 & MEM_Str)==0 ){
      return -1;
    }

    assert( pMem1->enc==pMem2->enc );
    assert( pMem1->enc==SQLITE_UTF8 || 
            pMem1->enc==SQLITE_UTF16LE || pMem1->enc==SQLITE_UTF16BE );

    /* The collation sequence must be defined at this point, even if
    ** the user deletes the collation sequence after the vdbe program is
    ** compiled (this was not always the case).
    */
    assert( !pColl || pColl->xCmp );

    if( pColl ){
      return vdbeCompareMemString(pMem1, pMem2, pColl);
    }
    /* If a NULL pointer was passed as the collate function, fall through
    ** to the blob case and use memcmp().  */
  }
 
  /* Both values must be blobs.  Compare using memcmp().  */
  rc = memcmp(pMem1->z, pMem2->z, (pMem1->n>pMem2->n)?pMem2->n:pMem1->n);
  if( rc==0 ){
    rc = pMem1->n - pMem2->n;
  }
  return rc;
}


/*
** The first argument passed to this function is a serial-type that
** corresponds to an integer - all values between 1 and 9 inclusive 
** except 7. The second points to a buffer containing an integer value
** serialized according to serial_type. This function deserializes
** and returns the value.
*/
static i64 vdbeRecordDecodeInt(u32 serial_type, const u8 *aKey){
  u32 y;
  assert( CORRUPT_DB || (serial_type>=1 && serial_type<=9 && serial_type!=7) );
  switch( serial_type ){
    case 0:
    case 1:
      return ONE_BYTE_INT(aKey);
    case 2:
      return TWO_BYTE_INT(aKey);
    case 3:
      return THREE_BYTE_INT(aKey);
    case 4: {
      y = FOUR_BYTE_UINT(aKey);
      return (i64)*(int*)&y;
    }
    case 5: {
      return FOUR_BYTE_UINT(aKey+2) + (((i64)1)<<32)*TWO_BYTE_INT(aKey);
    }
    case 6: {
      u64 x = FOUR_BYTE_UINT(aKey);
      x = (x<<32) | FOUR_BYTE_UINT(aKey+4);
      return (i64)*(i64*)&x;
    }
  }

  return (serial_type - 8);
}

/*
** This function compares the two table rows or index records
** specified by {nKey1, pKey1} and pPKey2.  It returns a negative, zero
** or positive integer if key1 is less than, equal to or 
** greater than key2.  The {nKey1, pKey1} key must be a blob
** created by th OP_MakeRecord opcode of the VDBE.  The pPKey2
** key must be a parsed key such as obtained from
** sqlite3VdbeParseRecord.
**
** If argument bSkip is non-zero, it is assumed that the caller has already
** determined that the first fields of the keys are equal.
**
** Key1 and Key2 do not have to contain the same number of fields. If all 
** fields that appear in both keys are equal, then pPKey2->default_rc is 
** returned.
*/
SQLITE_PRIVATE int sqlite3VdbeRecordCompare(
  int nKey1, const void *pKey1,   /* Left key */
  const UnpackedRecord *pPKey2,   /* Right key */
  int bSkip                       /* If true, skip the first field */
){
  u32 d1;                         /* Offset into aKey[] of next data element */
  int i;                          /* Index of next field to compare */
  u32 szHdr1;                     /* Size of record header in bytes */
  u32 idx1;                       /* Offset of first type in header */
  int rc = 0;                     /* Return value */
  Mem *pRhs = pPKey2->aMem;       /* Next field of pPKey2 to compare */
  KeyInfo *pKeyInfo = pPKey2->pKeyInfo;
  const unsigned char *aKey1 = (const unsigned char *)pKey1;
  Mem mem1;

  /* If bSkip is true, then the caller has already determined that the first
  ** two elements in the keys are equal. Fix the various stack variables so
  ** that this routine begins comparing at the second field. */
  if( bSkip ){
    u32 s1;
    idx1 = 1 + getVarint32(&aKey1[1], s1);
    szHdr1 = aKey1[0];
    d1 = szHdr1 + sqlite3VdbeSerialTypeLen(s1);
    i = 1;
    pRhs++;
  }else{
    idx1 = getVarint32(aKey1, szHdr1);
    d1 = szHdr1;
    i = 0;
  }

  VVA_ONLY( mem1.zMalloc = 0; ) /* Only needed by assert() statements */
  assert( pPKey2->pKeyInfo->nField+pPKey2->pKeyInfo->nXField>=pPKey2->nField 
       || CORRUPT_DB );
  assert( pPKey2->pKeyInfo->aSortOrder!=0 );
  assert( pPKey2->pKeyInfo->nField>0 );
  assert( idx1<=szHdr1 || CORRUPT_DB );
  do{
    u32 serial_type;

    /* RHS is an integer */
    if( pRhs->flags & MEM_Int ){
      serial_type = aKey1[idx1];
      if( serial_type>=12 ){
        rc = +1;
      }else if( serial_type==0 ){
        rc = -1;
      }else if( serial_type==7 ){
        double rhs = (double)pRhs->u.i;
        sqlite3VdbeSerialGet(&aKey1[d1], serial_type, &mem1);
        if( mem1.r<rhs ){
          rc = -1;
        }else if( mem1.r>rhs ){
          rc = +1;
        }
      }else{
        i64 lhs = vdbeRecordDecodeInt(serial_type, &aKey1[d1]);
        i64 rhs = pRhs->u.i;
        if( lhs<rhs ){
          rc = -1;
        }else if( lhs>rhs ){
          rc = +1;
        }
      }
    }

    /* RHS is real */
    else if( pRhs->flags & MEM_Real ){
      serial_type = aKey1[idx1];
      if( serial_type>=12 ){
        rc = +1;
      }else if( serial_type==0 ){
        rc = -1;
      }else{
        double rhs = pRhs->r;
        double lhs;
        sqlite3VdbeSerialGet(&aKey1[d1], serial_type, &mem1);
        if( serial_type==7 ){
          lhs = mem1.r;
        }else{
          lhs = (double)mem1.u.i;
        }
        if( lhs<rhs ){
          rc = -1;
        }else if( lhs>rhs ){
          rc = +1;
        }
      }
    }

    /* RHS is a string */
    else if( pRhs->flags & MEM_Str ){
      getVarint32(&aKey1[idx1], serial_type);
      if( serial_type<12 ){
        rc = -1;
      }else if( !(serial_type & 0x01) ){
        rc = +1;
      }else{
        mem1.n = (serial_type - 12) / 2;
        if( (d1+mem1.n) > (unsigned)nKey1 ){
          rc = 1;                /* Corruption */
        }else if( pKeyInfo->aColl[i] ){
          mem1.enc = pKeyInfo->enc;
          mem1.db = pKeyInfo->db;
          mem1.flags = MEM_Str;
          mem1.z = (char*)&aKey1[d1];
          rc = vdbeCompareMemString(&mem1, pRhs, pKeyInfo->aColl[i]);
        }else{
          int nCmp = MIN(mem1.n, pRhs->n);
          rc = memcmp(&aKey1[d1], pRhs->z, nCmp);
          if( rc==0 ) rc = mem1.n - pRhs->n; 
        }
      }
    }

    /* RHS is a blob */
    else if( pRhs->flags & MEM_Blob ){
      getVarint32(&aKey1[idx1], serial_type);
      if( serial_type<12 || (serial_type & 0x01) ){
        rc = -1;
      }else{
        int nStr = (serial_type - 12) / 2;
        if( (d1+nStr) > (unsigned)nKey1 ){
          rc = 1;                /* Corruption */
        }else{
          int nCmp = MIN(nStr, pRhs->n);
          rc = memcmp(&aKey1[d1], pRhs->z, nCmp);
          if( rc==0 ) rc = nStr - pRhs->n;
        }
      }
    }

    /* RHS is null */
    else{
      serial_type = aKey1[idx1];
      rc = (serial_type!=0);
    }

    if( rc!=0 ){
      if( pKeyInfo->aSortOrder[i] ){
        rc = -rc;
      }
      assert( CORRUPT_DB
          || (rc<0 && vdbeRecordCompareDebug(nKey1, pKey1, pPKey2)<0)
          || (rc>0 && vdbeRecordCompareDebug(nKey1, pKey1, pPKey2)>0)
          || pKeyInfo->db->mallocFailed
      );
      assert( mem1.zMalloc==0 );  /* See comment below */
      return rc;
    }

    i++;
    pRhs++;
    d1 += sqlite3VdbeSerialTypeLen(serial_type);
    idx1 += sqlite3VarintLen(serial_type);
  }while( idx1<(unsigned)szHdr1 && i<pPKey2->nField && d1<=(unsigned)nKey1 );

  /* No memory allocation is ever used on mem1.  Prove this using
  ** the following assert().  If the assert() fails, it indicates a
  ** memory leak and a need to call sqlite3VdbeMemRelease(&mem1).  */
  assert( mem1.zMalloc==0 );

  /* rc==0 here means that one or both of the keys ran out of fields and
  ** all the fields up to that point were equal. Return the the default_rc
  ** value.  */
  assert( CORRUPT_DB 
       || pPKey2->default_rc==vdbeRecordCompareDebug(nKey1, pKey1, pPKey2) 
  );
  return pPKey2->default_rc;
}

/*
** This function is an optimized version of sqlite3VdbeRecordCompare() 
** that (a) the first field of pPKey2 is an integer, and (b) the 
** size-of-header varint at the start of (pKey1/nKey1) fits in a single
** byte (i.e. is less than 128).
*/
static int vdbeRecordCompareInt(
  int nKey1, const void *pKey1, /* Left key */
  const UnpackedRecord *pPKey2, /* Right key */
  int bSkip                     /* Ignored */
){
  const u8 *aKey = &((const u8*)pKey1)[*(const u8*)pKey1 & 0x3F];
  int serial_type = ((const u8*)pKey1)[1];
  int res;
  u32 y;
  u64 x;
  i64 v = pPKey2->aMem[0].u.i;
  i64 lhs;
  UNUSED_PARAMETER(bSkip);

  assert( bSkip==0 );
  switch( serial_type ){
    case 1: { /* 1-byte signed integer */
      lhs = ONE_BYTE_INT(aKey);
      break;
    }
    case 2: { /* 2-byte signed integer */
      lhs = TWO_BYTE_INT(aKey);
      break;
    }
    case 3: { /* 3-byte signed integer */
      lhs = THREE_BYTE_INT(aKey);
      break;
    }
    case 4: { /* 4-byte signed integer */
      y = FOUR_BYTE_UINT(aKey);
      lhs = (i64)*(int*)&y;
      break;
    }
    case 5: { /* 6-byte signed integer */
      lhs = FOUR_BYTE_UINT(aKey+2) + (((i64)1)<<32)*TWO_BYTE_INT(aKey);
      break;
    }
    case 6: { /* 8-byte signed integer */
      x = FOUR_BYTE_UINT(aKey);
      x = (x<<32) | FOUR_BYTE_UINT(aKey+4);
      lhs = *(i64*)&x;
      break;
    }
    case 8: 
      lhs = 0;
      break;
    case 9:
      lhs = 1;
      break;

    /* This case could be removed without changing the results of running
    ** this code. Including it causes gcc to generate a faster switch 
    ** statement (since the range of switch targets now starts at zero and
    ** is contiguous) but does not cause any duplicate code to be generated
    ** (as gcc is clever enough to combine the two like cases). Other 
    ** compilers might be similar.  */ 
    case 0: case 7:
      return sqlite3VdbeRecordCompare(nKey1, pKey1, pPKey2, 0);

    default:
      return sqlite3VdbeRecordCompare(nKey1, pKey1, pPKey2, 0);
  }

  if( v>lhs ){
    res = pPKey2->r1;
  }else if( v<lhs ){
    res = pPKey2->r2;
  }else if( pPKey2->nField>1 ){
    /* The first fields of the two keys are equal. Compare the trailing 
    ** fields.  */
    res = sqlite3VdbeRecordCompare(nKey1, pKey1, pPKey2, 1);
  }else{
    /* The first fields of the two keys are equal and there are no trailing
    ** fields. Return pPKey2->default_rc in this case. */
    res = pPKey2->default_rc;
  }

  assert( (res==0 && vdbeRecordCompareDebug(nKey1, pKey1, pPKey2)==0)
       || (res<0 && vdbeRecordCompareDebug(nKey1, pKey1, pPKey2)<0)
       || (res>0 && vdbeRecordCompareDebug(nKey1, pKey1, pPKey2)>0)
       || CORRUPT_DB
  );
  return res;
}

/*
** This function is an optimized version of sqlite3VdbeRecordCompare() 
** that (a) the first field of pPKey2 is a string, that (b) the first field
** uses the collation sequence BINARY and (c) that the size-of-header varint 
** at the start of (pKey1/nKey1) fits in a single byte.
*/
static int vdbeRecordCompareString(
  int nKey1, const void *pKey1, /* Left key */
  const UnpackedRecord *pPKey2, /* Right key */
  int bSkip
){
  const u8 *aKey1 = (const u8*)pKey1;
  int serial_type;
  int res;
  UNUSED_PARAMETER(bSkip);

  assert( bSkip==0 );
  getVarint32(&aKey1[1], serial_type);

  if( serial_type<12 ){
    res = pPKey2->r1;      /* (pKey1/nKey1) is a number or a null */
  }else if( !(serial_type & 0x01) ){ 
    res = pPKey2->r2;      /* (pKey1/nKey1) is a blob */
  }else{
    int nCmp;
    int nStr;
    int szHdr = aKey1[0];

    nStr = (serial_type-12) / 2;
    if( (szHdr + nStr) > nKey1 ) return 0;    /* Corruption */
    nCmp = MIN( pPKey2->aMem[0].n, nStr );
    res = memcmp(&aKey1[szHdr], pPKey2->aMem[0].z, nCmp);

    if( res==0 ){
      res = nStr - pPKey2->aMem[0].n;
      if( res==0 ){
        if( pPKey2->nField>1 ){
          res = sqlite3VdbeRecordCompare(nKey1, pKey1, pPKey2, 1);
        }else{
          res = pPKey2->default_rc;
        }
      }else if( res>0 ){
        res = pPKey2->r2;
      }else{
        res = pPKey2->r1;
      }
    }else if( res>0 ){
      res = pPKey2->r2;
    }else{
      res = pPKey2->r1;
    }
  }

  assert( (res==0 && vdbeRecordCompareDebug(nKey1, pKey1, pPKey2)==0)
       || (res<0 && vdbeRecordCompareDebug(nKey1, pKey1, pPKey2)<0)
       || (res>0 && vdbeRecordCompareDebug(nKey1, pKey1, pPKey2)>0)
       || CORRUPT_DB
  );
  return res;
}

/*
** Return a pointer to an sqlite3VdbeRecordCompare() compatible function
** suitable for comparing serialized records to the unpacked record passed
** as the only argument.
*/
SQLITE_PRIVATE RecordCompare sqlite3VdbeFindCompare(UnpackedRecord *p){
  /* varintRecordCompareInt() and varintRecordCompareString() both assume
  ** that the size-of-header varint that occurs at the start of each record
  ** fits in a single byte (i.e. is 127 or less). varintRecordCompareInt()
  ** also assumes that it is safe to overread a buffer by at least the 
  ** maximum possible legal header size plus 8 bytes. Because there is
  ** guaranteed to be at least 74 (but not 136) bytes of padding following each
  ** buffer passed to varintRecordCompareInt() this makes it convenient to
  ** limit the size of the header to 64 bytes in cases where the first field
  ** is an integer.
  **
  ** The easiest way to enforce this limit is to consider only records with
  ** 13 fields or less. If the first field is an integer, the maximum legal
  ** header size is (12*5 + 1 + 1) bytes.  */
  if( (p->pKeyInfo->nField + p->pKeyInfo->nXField)<=13 ){
    int flags = p->aMem[0].flags;
    if( p->pKeyInfo->aSortOrder[0] ){
      p->r1 = 1;
      p->r2 = -1;
    }else{
      p->r1 = -1;
      p->r2 = 1;
    }
    if( (flags & MEM_Int) ){
      return vdbeRecordCompareInt;
    }
    if( (flags & (MEM_Int|MEM_Real|MEM_Null|MEM_Blob))==0 
        && p->pKeyInfo->aColl[0]==0 
    ){
      return vdbeRecordCompareString;
    }
  }

  return sqlite3VdbeRecordCompare;
}

/*
** pCur points at an index entry created using the OP_MakeRecord opcode.
** Read the rowid (the last field in the record) and store it in *rowid.
** Return SQLITE_OK if everything works, or an error code otherwise.
**
** pCur might be pointing to text obtained from a corrupt database file.

**
** pUnpacked is either created without a rowid or is truncated so that it
** omits the rowid at the end.  The rowid at the end of the index entry
** is ignored as well.  Hence, this routine only compares the prefixes 
** of the keys prior to the final rowid, not the entire key.
*/
SQLITE_PRIVATE int sqlite3VdbeIdxKeyCompare(
  VdbeCursor *pC,                  /* The cursor to compare against */
  const UnpackedRecord *pUnpacked, /* Unpacked version of key */
  int *res                         /* Write the comparison result here */
){
  i64 nCellKey = 0;
  int rc;
  BtCursor *pCur = pC->pCursor;
  Mem m;

  assert( sqlite3BtreeCursorIsValid(pCur) );
  VVA_ONLY(rc =) sqlite3BtreeKeySize(pCur, &nCellKey);
  assert( rc==SQLITE_OK );    /* pCur is always valid so KeySize cannot fail */
  /* nCellKey will always be between 0 and 0xffffffff because of the way
  ** that btreeParseCellPtr() and sqlite3GetVarint32() are implemented */
  if( nCellKey<=0 || nCellKey>0x7fffffff ){
    *res = 0;
    return SQLITE_CORRUPT_BKPT;
  }
  memset(&m, 0, sizeof(m));
  rc = sqlite3VdbeMemFromBtree(pC->pCursor, 0, (u32)nCellKey, 1, &m);
  if( rc ){
    return rc;
  }

  *res = sqlite3VdbeRecordCompare(m.n, m.z, pUnpacked, 0);
  sqlite3VdbeMemRelease(&m);
  return SQLITE_OK;
}

/*
** This routine sets the value to be returned by subsequent calls to
** sqlite3_changes() on the database handle 'db'. 

  if( v ){
    Mem *pMem = &v->aVar[iVar-1];
    if( 0==(pMem->flags & MEM_Null) ){
      sqlite3_value *pRet = sqlite3ValueNew(v->db);
      if( pRet ){
        sqlite3VdbeMemCopy((Mem *)pRet, pMem);
        sqlite3ValueApplyAffinity(pRet, aff, SQLITE_UTF8);

      }
      return pRet;
    }
  }
  return 0;
}

** The following routines extract information from a Mem or sqlite3_value
** structure.
*/
SQLITE_API const void *sqlite3_value_blob(sqlite3_value *pVal){
  Mem *p = (Mem*)pVal;
  if( p->flags & (MEM_Blob|MEM_Str) ){
    sqlite3VdbeMemExpandBlob(p);

    p->flags |= MEM_Blob;
    return p->n ? p->z : 0;
  }else{
    return sqlite3_value_text(pVal);
  }
}
SQLITE_API int sqlite3_value_bytes(sqlite3_value *pVal){

  return sqlite3ValueText(pVal, SQLITE_UTF16BE);
}
SQLITE_API const void *sqlite3_value_text16le(sqlite3_value *pVal){
  return sqlite3ValueText(pVal, SQLITE_UTF16LE);
}
#endif /* SQLITE_OMIT_UTF16 */
SQLITE_API int sqlite3_value_type(sqlite3_value* pVal){
  static const u8 aType[] = {
     SQLITE_BLOB,     /* 0x00 */
     SQLITE_NULL,     /* 0x01 */
     SQLITE_TEXT,     /* 0x02 */
     SQLITE_NULL,     /* 0x03 */
     SQLITE_INTEGER,  /* 0x04 */
     SQLITE_NULL,     /* 0x05 */
     SQLITE_INTEGER,  /* 0x06 */
     SQLITE_NULL,     /* 0x07 */
     SQLITE_FLOAT,    /* 0x08 */
     SQLITE_NULL,     /* 0x09 */
     SQLITE_FLOAT,    /* 0x0a */
     SQLITE_NULL,     /* 0x0b */
     SQLITE_INTEGER,  /* 0x0c */
     SQLITE_NULL,     /* 0x0d */
     SQLITE_INTEGER,  /* 0x0e */
     SQLITE_NULL,     /* 0x0f */
     SQLITE_BLOB,     /* 0x10 */
     SQLITE_NULL,     /* 0x11 */
     SQLITE_TEXT,     /* 0x12 */
     SQLITE_NULL,     /* 0x13 */
     SQLITE_INTEGER,  /* 0x14 */
     SQLITE_NULL,     /* 0x15 */
     SQLITE_INTEGER,  /* 0x16 */
     SQLITE_NULL,     /* 0x17 */
     SQLITE_FLOAT,    /* 0x18 */
     SQLITE_NULL,     /* 0x19 */
     SQLITE_FLOAT,    /* 0x1a */
     SQLITE_NULL,     /* 0x1b */
     SQLITE_INTEGER,  /* 0x1c */
     SQLITE_NULL,     /* 0x1d */
     SQLITE_INTEGER,  /* 0x1e */
     SQLITE_NULL,     /* 0x1f */
  };
  return aType[pVal->flags&MEM_AffMask];
}

/**************************** sqlite3_result_  *******************************
** The following routines are used by user-defined functions to specify
** the function result.
**
** The setStrOrError() funtion calls sqlite3VdbeMemSetStr() to store the

*/
SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt){
  Vdbe *pVm = (Vdbe *)pStmt;
  if( pVm==0 || pVm->pResultSet==0 ) return 0;
  return pVm->nResColumn;
}

/*
** Return a pointer to static memory containing an SQL NULL value.
*/
static const Mem *columnNullValue(void){
  /* Even though the Mem structure contains an element
  ** of type i64, on certain architectures (x86) with certain compiler
  ** switches (-Os), gcc may align this Mem object on a 4-byte boundary
  ** instead of an 8-byte one. This all works fine, except that when
  ** running with SQLITE_DEBUG defined the SQLite code sometimes assert()s
  ** that a Mem structure is located on an 8-byte boundary. To prevent
  ** these assert()s from failing, when building with SQLITE_DEBUG defined
  ** using gcc, we force nullMem to be 8-byte aligned using the magical
  ** __attribute__((aligned(8))) macro.  */
  static const Mem nullMem 
#if defined(SQLITE_DEBUG) && defined(__GNUC__)
    __attribute__((aligned(8))) 
#endif
    = {0, "", (double)0, {0}, 0, MEM_Null, 0,
#ifdef SQLITE_DEBUG
       0, 0,  /* pScopyFrom, pFiller */
#endif
       0, 0 };
  return &nullMem;
}

/*
** Check to see if column iCol of the given statement is valid.  If
** it is, return a pointer to the Mem for the value of that column.
** If iCol is not valid, return a pointer to a Mem which has a value
** of NULL.
*/
static Mem *columnMem(sqlite3_stmt *pStmt, int i){
  Vdbe *pVm;
  Mem *pOut;

  pVm = (Vdbe *)pStmt;
  if( pVm && pVm->pResultSet!=0 && i<pVm->nResColumn && i>=0 ){
    sqlite3_mutex_enter(pVm->db->mutex);
    pOut = &pVm->pResultSet[i];
  }else{





















    if( pVm && ALWAYS(pVm->db) ){
      sqlite3_mutex_enter(pVm->db->mutex);
      sqlite3Error(pVm->db, SQLITE_RANGE, 0);
    }
    pOut = (Mem*)columnNullValue();
  }
  return pOut;
}

/*
** This function is called after invoking an sqlite3_value_XXX function on a 
** column value (i.e. a value returned by evaluating an SQL expression in the

  void (*xDel)(void*)
){
  return bindText(pStmt, i, zData, nData, xDel, SQLITE_UTF16NATIVE);
}
#endif /* SQLITE_OMIT_UTF16 */
SQLITE_API int sqlite3_bind_value(sqlite3_stmt *pStmt, int i, const sqlite3_value *pValue){
  int rc;
  switch( sqlite3_value_type((sqlite3_value*)pValue) ){
    case SQLITE_INTEGER: {
      rc = sqlite3_bind_int64(pStmt, i, pValue->u.i);
      break;
    }
    case SQLITE_FLOAT: {
      rc = sqlite3_bind_double(pStmt, i, pValue->r);
      break;

** 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.
**
*************************************************************************
** The code in this file implements the function that runs the









** bytecode of a prepared statement.
















**
** Various scripts scan this source file in order to generate HTML
** documentation, headers files, or other derived files.  The formatting
** of the code in this file is, therefore, important.  See other comments
** in this file for details.  If in doubt, do not deviate from existing
** commenting and indentation practices when changing or adding code.
*/

/*
** Invoke this macro on memory cells just prior to changing the
** value of the cell.  This macro verifies that shallow copies are
** not misused.  A shallow copy of a string or blob just copies a
** pointer to the string or blob, not the content.  If the original
** is changed while the copy is still in use, the string or blob might
** be changed out from under the copy.  This macro verifies that nothing
** like that every happens.
*/
#ifdef SQLITE_DEBUG
# define memAboutToChange(P,M) sqlite3VdbeMemAboutToChange(P,M)
#else
# define memAboutToChange(P,M)
#endif

  if( (p->flags & (MEM_Str|MEM_Blob))!=0 && p->n>sqlite3_max_blobsize ){
    sqlite3_max_blobsize = p->n;
  }
}
#endif

/*
** The next global variable is incremented each time the OP_Found opcode
** is executed. This is used to test whether or not the foreign key
** operation implemented using OP_FkIsZero is working. This variable
** has no function other than to help verify the correct operation of the
** library.
*/
#ifdef SQLITE_TEST
SQLITE_API int sqlite3_found_count = 0;
#endif

/*
** Test a register to see if it exceeds the current maximum blob size.
** If it does, record the new maximum blob size.
*/
#if defined(SQLITE_TEST) && !defined(SQLITE_OMIT_BUILTIN_TEST)
# define UPDATE_MAX_BLOBSIZE(P)  updateMaxBlobsize(P)
#else
# define UPDATE_MAX_BLOBSIZE(P)
#endif

/*
** Invoke the VDBE coverage callback, if that callback is defined.  This
** feature is used for test suite validation only and does not appear an
** production builds.
**
** M is an integer, 2 or 3, that indices how many different ways the
** branch can go.  It is usually 2.  "I" is the direction the branch
** goes.  0 means falls through.  1 means branch is taken.  2 means the
** second alternative branch is taken.
*/
#if !defined(SQLITE_VDBE_COVERAGE)
# define VdbeBranchTaken(I,M)
#else
# define VdbeBranchTaken(I,M) vdbeTakeBranch(pOp->iSrcLine,I,M)
  static void vdbeTakeBranch(int iSrcLine, u8 I, u8 M){
    if( iSrcLine<=2 && ALWAYS(iSrcLine>0) ){
      M = iSrcLine;
      /* Assert the truth of VdbeCoverageAlwaysTaken() and 
      ** VdbeCoverageNeverTaken() */
      assert( (M & I)==I );
    }else{
      if( sqlite3GlobalConfig.xVdbeBranch==0 ) return;  /*NO_TEST*/
      sqlite3GlobalConfig.xVdbeBranch(sqlite3GlobalConfig.pVdbeBranchArg,
                                      iSrcLine,I,M);
    }
  }
#endif

/*
** Convert the given register into a string if it isn't one
** already. Return non-zero if a malloc() fails.
*/
#define Stringify(P, enc) \
   if(((P)->flags&(MEM_Str|MEM_Blob))==0 && sqlite3VdbeMemStringify(P,enc)) \
     { goto no_mem; }

/*
** An ephemeral string value (signified by the MEM_Ephem flag) contains
** a pointer to a dynamically allocated string where some other entity
** is responsible for deallocating that string.  Because the register
** does not control the string, it might be deleted without the register
** knowing it.
**
** This routine converts an ephemeral string into a dynamically allocated
** string that the register itself controls.  In other words, it
** converts an MEM_Ephem string into a string with P.z==P.zMalloc.
*/
#define Deephemeralize(P) \
   if( ((P)->flags&MEM_Ephem)!=0 \
       && sqlite3VdbeMemMakeWriteable(P) ){ goto no_mem;}

/* Return true if the cursor was opened using the OP_OpenSorter opcode. */
#define isSorter(x) ((x)->pSorter!=0)

























/*
** Allocate VdbeCursor number iCur.  Return a pointer to it.  Return NULL
** if we run out of memory.
*/
static VdbeCursor *allocateCursor(
  Vdbe *p,              /* The virtual machine */

/*
** Try to convert the type of a function argument or a result column
** into a numeric representation.  Use either INTEGER or REAL whichever
** is appropriate.  But only do the conversion if it is possible without
** loss of information and return the revised type of the argument.
*/
SQLITE_API int sqlite3_value_numeric_type(sqlite3_value *pVal){
  int eType = sqlite3_value_type(pVal);
  if( eType==SQLITE_TEXT ){
    Mem *pMem = (Mem*)pVal;

    applyNumericAffinity(pMem);
    eType = sqlite3_value_type(pVal);
  }
  return eType;
}

/*
** Exported version of applyAffinity(). This one works on sqlite3_value*, 
** not the internal Mem* type.
*/
SQLITE_PRIVATE void sqlite3ValueApplyAffinity(

#endif

#ifdef SQLITE_DEBUG
/*
** Print the value of a register for tracing purposes:
*/
static void memTracePrint(Mem *p){
  if( p->flags & MEM_Undefined ){
    printf(" undefined");
  }else if( p->flags & MEM_Null ){
    printf(" NULL");
  }else if( (p->flags & (MEM_Int|MEM_Str))==(MEM_Int|MEM_Str) ){
    printf(" si:%lld", p->u.i);
  }else if( p->flags & MEM_Int ){
    printf(" i:%lld", p->u.i);

#endif /* !defined(_HWTIME_H_) */

/************** End of hwtime.h **********************************************/
/************** Continuing where we left off in vdbe.c ***********************/

#endif















#ifndef NDEBUG
/*
** This function is only called from within an assert() expression. It
** checks that the sqlite3.nTransaction variable is correctly set to
** the number of non-transaction savepoints currently in the 
** linked list starting at sqlite3.pSavepoint.

  assert( n==(db->nSavepoint + db->isTransactionSavepoint) );
  return 1;
}
#endif


/*
** Execute as much of a VDBE program as we can.














** This is the core of sqlite3_step().  













*/
SQLITE_PRIVATE int sqlite3VdbeExec(
  Vdbe *p                    /* The VDBE */
){
  int pc=0;                  /* The program counter */
  Op *aOp = p->aOp;          /* Copy of p->aOp */
  Op *pOp;                   /* Current operation */

  Mem *pIn2 = 0;             /* 2nd input operand */
  Mem *pIn3 = 0;             /* 3rd input operand */
  Mem *pOut = 0;             /* Output operand */
  int *aPermute = 0;         /* Permutation of columns for OP_Compare */
  i64 lastRowid = db->lastRowid;  /* Saved value of the last insert ROWID */
#ifdef VDBE_PROFILE
  u64 start;                 /* CPU clock count at start of opcode */

#endif
  /*** INSERT STACK UNION HERE ***/

  assert( p->magic==VDBE_MAGIC_RUN );  /* sqlite3_step() verifies this */
  sqlite3VdbeEnter(p);
  if( p->rc==SQLITE_NOMEM ){
    /* This happens if a malloc() inside a call to sqlite3_column_text() or
    ** sqlite3_column_text16() failed.  */
    goto no_mem;
  }
  assert( p->rc==SQLITE_OK || p->rc==SQLITE_BUSY );
  assert( p->bIsReader || p->readOnly!=0 );
  p->rc = SQLITE_OK;
  p->iCurrentTime = 0;
  assert( p->explain==0 );
  p->pResultSet = 0;
  db->busyHandler.nBusy = 0;
  if( db->u1.isInterrupted ) goto abort_due_to_interrupt;
  sqlite3VdbeIOTraceSql(p);
#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
  if( db->xProgress ){
    assert( 0 < db->nProgressOps );
    nProgressLimit = (unsigned)p->aCounter[SQLITE_STMTSTATUS_VM_STEP];
    if( nProgressLimit==0 ){
      nProgressLimit = db->nProgressOps;

  }
  sqlite3EndBenignMalloc();
#endif
  for(pc=p->pc; rc==SQLITE_OK; pc++){
    assert( pc>=0 && pc<p->nOp );
    if( db->mallocFailed ) goto no_mem;
#ifdef VDBE_PROFILE

    start = sqlite3Hwtime();
#endif
    nVmStep++;
    pOp = &aOp[pc];

    /* Only allow tracing if SQLITE_DEBUG is defined.
    */

    /* Sanity checking on other operands */
#ifdef SQLITE_DEBUG
    if( (pOp->opflags & OPFLG_IN1)!=0 ){
      assert( pOp->p1>0 );
      assert( pOp->p1<=(p->nMem-p->nCursor) );
      assert( memIsValid(&aMem[pOp->p1]) );
      assert( sqlite3VdbeCheckMemInvariants(&aMem[pOp->p1]) );
      REGISTER_TRACE(pOp->p1, &aMem[pOp->p1]);
    }
    if( (pOp->opflags & OPFLG_IN2)!=0 ){
      assert( pOp->p2>0 );
      assert( pOp->p2<=(p->nMem-p->nCursor) );
      assert( memIsValid(&aMem[pOp->p2]) );
      assert( sqlite3VdbeCheckMemInvariants(&aMem[pOp->p2]) );
      REGISTER_TRACE(pOp->p2, &aMem[pOp->p2]);
    }
    if( (pOp->opflags & OPFLG_IN3)!=0 ){
      assert( pOp->p3>0 );
      assert( pOp->p3<=(p->nMem-p->nCursor) );
      assert( memIsValid(&aMem[pOp->p3]) );
      assert( sqlite3VdbeCheckMemInvariants(&aMem[pOp->p3]) );
      REGISTER_TRACE(pOp->p3, &aMem[pOp->p3]);
    }
    if( (pOp->opflags & OPFLG_OUT2)!=0 ){
      assert( pOp->p2>0 );
      assert( pOp->p2<=(p->nMem-p->nCursor) );
      memAboutToChange(p, &aMem[pOp->p2]);
    }

  **
  ** This code uses unstructured "goto" statements and does not look clean.
  ** But that is not due to sloppy coding habits. The code is written this
  ** way for performance, to avoid having to run the interrupt and progress
  ** checks on every opcode.  This helps sqlite3_step() to run about 1.5%
  ** faster according to "valgrind --tool=cachegrind" */
check_for_interrupt:
  if( db->u1.isInterrupted ) goto abort_due_to_interrupt;
#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
  /* Call the progress callback if it is configured and the required number
  ** of VDBE ops have been executed (either since this invocation of
  ** sqlite3VdbeExec() or since last time the progress callback was called).
  ** If the progress callback returns non-zero, exit the virtual machine with
  ** a return code SQLITE_ABORT.
  */

**
** Write the current address onto register P1
** and then jump to address P2.
*/
case OP_Gosub: {            /* jump */
  assert( pOp->p1>0 && pOp->p1<=(p->nMem-p->nCursor) );
  pIn1 = &aMem[pOp->p1];
  assert( VdbeMemDynamic(pIn1)==0 );
  memAboutToChange(p, pIn1);
  pIn1->flags = MEM_Int;
  pIn1->u.i = pc;
  REGISTER_TRACE(pOp->p1, pIn1);
  pc = pOp->p2 - 1;
  break;
}

/* Opcode:  Return P1 * * * *
**
** Jump to the next instruction after the address in register P1.  After
** the jump, register P1 becomes undefined.
*/
case OP_Return: {           /* in1 */
  pIn1 = &aMem[pOp->p1];
  assert( pIn1->flags==MEM_Int );
  pc = (int)pIn1->u.i;
  pIn1->flags = MEM_Undefined;
  break;
}

/* Opcode: InitCoroutine P1 P2 P3 * *
**
** Set up register P1 so that it will OP_Yield to the co-routine
** located at address P3.
**
** If P2!=0 then the co-routine implementation immediately follows
** this opcode.  So jump over the co-routine implementation to
** address P2.
*/
case OP_InitCoroutine: {     /* jump */
  assert( pOp->p1>0 &&  pOp->p1<=(p->nMem-p->nCursor) );
  assert( pOp->p2>=0 && pOp->p2<p->nOp );
  assert( pOp->p3>=0 && pOp->p3<p->nOp );
  pOut = &aMem[pOp->p1];
  assert( !VdbeMemDynamic(pOut) );
  pOut->u.i = pOp->p3 - 1;
  pOut->flags = MEM_Int;
  if( pOp->p2 ) pc = pOp->p2 - 1;
  break;
}

/* Opcode:  EndCoroutine P1 * * * *
**
** The instruction at the address in register P1 is an OP_Yield.
** Jump to the P2 parameter of that OP_Yield.
** After the jump, register P1 becomes undefined.
*/
case OP_EndCoroutine: {           /* in1 */
  VdbeOp *pCaller;
  pIn1 = &aMem[pOp->p1];
  assert( pIn1->flags==MEM_Int );
  assert( pIn1->u.i>=0 && pIn1->u.i<p->nOp );
  pCaller = &aOp[pIn1->u.i];
  assert( pCaller->opcode==OP_Yield );
  assert( pCaller->p2>=0 && pCaller->p2<p->nOp );
  pc = pCaller->p2 - 1;
  pIn1->flags = MEM_Undefined;
  break;
}

/* Opcode:  Yield P1 P2 * * *
**
** Swap the program counter with the value in register P1.
**
** If the co-routine ends with OP_Yield or OP_Return then continue
** to the next instruction.  But if the co-routine ends with
** OP_EndCoroutine, jump immediately to P2.
*/
case OP_Yield: {            /* in1, jump */
  int pcDest;
  pIn1 = &aMem[pOp->p1];
  assert( VdbeMemDynamic(pIn1)==0 );
  pIn1->flags = MEM_Int;
  pcDest = (int)pIn1->u.i;
  pIn1->u.i = pc;
  REGISTER_TRACE(pOp->p1, pIn1);
  pc = pcDest;
  break;
}

/* Opcode:  HaltIfNull  P1 P2 P3 P4 P5
** Synopsis:  if r[P3]=null halt
**
** Check the value in register P3.  If it is NULL then Halt using
** parameter P1, P2, and P4 as if this were a Halt instruction.  If the
** value in register P3 is not NULL, then this routine is a no-op.
** The P5 parameter should be 1.
*/
case OP_HaltIfNull: {      /* in3 */

}
#endif

/* Opcode: String8 * P2 * P4 *
** Synopsis: r[P2]='P4'
**
** P4 points to a nul terminated UTF-8 string. This opcode is transformed 
** into an OP_String before it is executed for the first time.  During
** this transformation, the length of string P4 is computed and stored
** as the P1 parameter.
*/
case OP_String8: {         /* same as TK_STRING, out2-prerelease */
  assert( pOp->p4.z!=0 );
  pOp->opcode = OP_String;
  pOp->p1 = sqlite3Strlen30(pOp->p4.z);

#ifndef SQLITE_OMIT_UTF16
  if( encoding!=SQLITE_UTF8 ){
    rc = sqlite3VdbeMemSetStr(pOut, pOp->p4.z, -1, SQLITE_UTF8, SQLITE_STATIC);
    if( rc==SQLITE_TOOBIG ) goto too_big;
    if( SQLITE_OK!=sqlite3VdbeChangeEncoding(pOut, encoding) ) goto no_mem;
    assert( pOut->zMalloc==pOut->z );
    assert( VdbeMemDynamic(pOut)==0 );
    pOut->zMalloc = 0;
    pOut->flags |= MEM_Static;

    if( pOp->p4type==P4_DYNAMIC ){
      sqlite3DbFree(db, pOp->p4.z);
    }
    pOp->p4type = P4_DYNAMIC;
    pOp->p4.z = pOut->z;
    pOp->p1 = pOut->n;
  }

    VdbeMemRelease(pOut);
    pOut->flags = nullFlag;
    cnt--;
  }
  break;
}

/* Opcode: SoftNull P1 * * * *
** Synopsis:  r[P1]=NULL
**
** Set register P1 to have the value NULL as seen by the OP_MakeRecord
** instruction, but do not free any string or blob memory associated with
** the register, so that if the value was a string or blob that was
** previously copied using OP_SCopy, the copies will continue to be valid.
*/
case OP_SoftNull: {
  assert( pOp->p1>0 && pOp->p1<=(p->nMem-p->nCursor) );
  pOut = &aMem[pOp->p1];
  pOut->flags = (pOut->flags|MEM_Null)&~MEM_Undefined;
  break;
}

/* Opcode: Blob P1 P2 * P4 *
** Synopsis: r[P2]=P4 (len=P1)
**
** P4 points to a blob of data P1 bytes long.  Store this
** blob in register P2.
*/
case OP_Blob: {                /* out2-prerelease */
  assert( pOp->p1 <= SQLITE_MAX_LENGTH );
  sqlite3VdbeMemSetStr(pOut, pOp->p4.z, pOp->p1, 0, 0);
  pOut->enc = encoding;
  UPDATE_MAX_BLOBSIZE(pOut);
  break;
}

/* Opcode: Variable P1 P2 * P4 *
** Synopsis: r[P2]=parameter(P1,P4)
**
** Transfer the values of bound parameter P1 into register P2
**
** If the parameter is named, then its name appears in P4.
** The P4 value is used by sqlite3_bind_parameter_name().
*/
case OP_Variable: {            /* out2-prerelease */
  Mem *pVar;       /* Value being transferred */

  assert( pOp->p1>0 && pOp->p1<=p->nVar );
  assert( pOp->p4.z==0 || pOp->p4.z==p->azVar[pOp->p1-1] );

  pIn1 = &aMem[p1];
  pOut = &aMem[p2];
  do{
    assert( pOut<=&aMem[(p->nMem-p->nCursor)] );
    assert( pIn1<=&aMem[(p->nMem-p->nCursor)] );
    assert( memIsValid(pIn1) );
    memAboutToChange(p, pOut);
    VdbeMemRelease(pOut);
    zMalloc = pOut->zMalloc;

    memcpy(pOut, pIn1, sizeof(Mem));
#ifdef SQLITE_DEBUG
    if( pOut->pScopyFrom>=&aMem[p1] && pOut->pScopyFrom<&aMem[p1+pOp->p3] ){
      pOut->pScopyFrom += p1 - pOp->p2;
    }
#endif
    pIn1->flags = MEM_Undefined;
    pIn1->xDel = 0;
    pIn1->zMalloc = zMalloc;
    REGISTER_TRACE(p2++, pOut);
    pIn1++;
    pOut++;
  }while( n-- );
  break;
}

/* Opcode: ResultRow P1 P2 * * *
** Synopsis:  output=r[P1@P2]
**
** The registers P1 through P1+P2-1 contain a single row of
** results. This opcode causes the sqlite3_step() call to terminate
** with an SQLITE_ROW return code and it sets up the sqlite3_stmt
** structure to provide access to the r(P1)..r(P1+P2-1) values as
** the result row.
*/
case OP_ResultRow: {
  Mem *pMem;
  int i;
  assert( p->nResColumn==pOp->p2 );
  assert( pOp->p1>0 );
  assert( pOp->p1+pOp->p2<=(p->nMem-p->nCursor)+1 );

  pMem = p->pResultSet = &aMem[pOp->p1];
  for(i=0; i<pOp->p2; i++){
    assert( memIsValid(&pMem[i]) );
    Deephemeralize(&pMem[i]);
    assert( (pMem[i].flags & MEM_Ephem)==0
            || (pMem[i].flags & (MEM_Str|MEM_Blob))==0 );
    sqlite3VdbeMemNulTerminate(&pMem[i]);

    REGISTER_TRACE(pOp->p1+i, &pMem[i]);
  }
  if( db->mallocFailed ) goto no_mem;

  /* Return SQLITE_ROW
  */
  p->pc = pc + 1;

  if( ExpandBlob(pIn1) || ExpandBlob(pIn2) ) goto no_mem;
  Stringify(pIn1, encoding);
  Stringify(pIn2, encoding);
  nByte = pIn1->n + pIn2->n;
  if( nByte>db->aLimit[SQLITE_LIMIT_LENGTH] ){
    goto too_big;
  }

  if( sqlite3VdbeMemGrow(pOut, (int)nByte+2, pOut==pIn2) ){
    goto no_mem;
  }
  MemSetTypeFlag(pOut, MEM_Str);
  if( pOut!=pIn2 ){
    memcpy(pOut->z, pIn2->z, pIn2->n);
  }
  memcpy(&pOut->z[pIn2->n], pIn1->z, pIn1->n);
  pOut->z[nByte]=0;
  pOut->z[nByte+1] = 0;
  pOut->flags |= MEM_Term;

  assert( n==0 || (pOp->p2>0 && pOp->p2+n<=(p->nMem-p->nCursor)+1) );
  assert( pOp->p3<pOp->p2 || pOp->p3>=pOp->p2+n );
  pArg = &aMem[pOp->p2];
  for(i=0; i<n; i++, pArg++){
    assert( memIsValid(pArg) );
    apVal[i] = pArg;
    Deephemeralize(pArg);

    REGISTER_TRACE(pOp->p2+i, pArg);
  }

  assert( pOp->p4type==P4_FUNCDEF );
  ctx.pFunc = pOp->p4.pFunc;
  ctx.iOp = pc;
  ctx.pVdbe = p;

** without data loss, then jump immediately to P2, or if P2==0
** raise an SQLITE_MISMATCH exception.
*/
case OP_MustBeInt: {            /* jump, in1 */
  pIn1 = &aMem[pOp->p1];
  if( (pIn1->flags & MEM_Int)==0 ){
    applyAffinity(pIn1, SQLITE_AFF_NUMERIC, encoding);
    VdbeBranchTaken((pIn1->flags&MEM_Int)==0, 2);
    if( (pIn1->flags & MEM_Int)==0 ){
      if( pOp->p2==0 ){
        rc = SQLITE_MISMATCH;
        goto abort_due_to_error;
      }else{
        pc = pOp->p2 - 1;
        break;

#endif

#ifndef SQLITE_OMIT_CAST
/* Opcode: ToText P1 * * * *
**
** Force the value in register P1 to be text.
** If the value is numeric, convert it to a string using the
** equivalent of sprintf().  Blob values are unchanged and
** are afterwards simply interpreted as text.
**
** A NULL value is not changed by this routine.  It remains NULL.
*/
case OP_ToText: {                  /* same as TK_TO_TEXT, in1 */
  pIn1 = &aMem[pOp->p1];
  memAboutToChange(p, pIn1);

    if( pOp->p5 & SQLITE_NULLEQ ){
      /* If SQLITE_NULLEQ is set (which will only happen if the operator is
      ** OP_Eq or OP_Ne) then take the jump or not depending on whether
      ** or not both operands are null.
      */
      assert( pOp->opcode==OP_Eq || pOp->opcode==OP_Ne );
      assert( (flags1 & MEM_Cleared)==0 );
      assert( (pOp->p5 & SQLITE_JUMPIFNULL)==0 );
      if( (flags1&MEM_Null)!=0
       && (flags3&MEM_Null)!=0
       && (flags3&MEM_Cleared)==0
      ){
        res = 0;  /* Results are equal */
      }else{
        res = 1;  /* Results are not equal */
      }
    }else{
      /* SQLITE_NULLEQ is clear and at least one operand is NULL,
      ** then the result is always NULL.
      ** The jump is taken if the SQLITE_JUMPIFNULL bit is set.
      */
      if( pOp->p5 & SQLITE_STOREP2 ){


        pOut = &aMem[pOp->p2];
        MemSetTypeFlag(pOut, MEM_Null);
        REGISTER_TRACE(pOp->p2, pOut);
      }else{
        VdbeBranchTaken(2,3);
        if( pOp->p5 & SQLITE_JUMPIFNULL ){
          pc = pOp->p2-1;
        }
      }
      break;
    }
  }else{
    /* Neither operand is NULL.  Do a comparison. */
    affinity = pOp->p5 & SQLITE_AFF_MASK;
    if( affinity ){

  if( pOp->p5 & SQLITE_STOREP2 ){
    pOut = &aMem[pOp->p2];
    memAboutToChange(p, pOut);
    MemSetTypeFlag(pOut, MEM_Int);
    pOut->u.i = res;
    REGISTER_TRACE(pOp->p2, pOut);
  }else{
    VdbeBranchTaken(res!=0, (pOp->p5 & SQLITE_NULLEQ)?2:3);
    if( res ){
      pc = pOp->p2-1;
    }
  }
  /* Undo any changes made by applyAffinity() to the input registers. */
  pIn1->flags = (pIn1->flags&~MEM_TypeMask) | (flags1&MEM_TypeMask);
  pIn3->flags = (pIn3->flags&~MEM_TypeMask) | (flags3&MEM_TypeMask);
  break;
}

/* Opcode: Permutation * * * P4 *

**
** Jump to the instruction at address P1, P2, or P3 depending on whether
** in the most recent OP_Compare instruction the P1 vector was less than
** equal to, or greater than the P2 vector, respectively.
*/
case OP_Jump: {             /* jump */
  if( iCompare<0 ){
    pc = pOp->p1 - 1;  VdbeBranchTaken(0,3);
  }else if( iCompare==0 ){
    pc = pOp->p2 - 1;  VdbeBranchTaken(1,3);
  }else{
    pc = pOp->p3 - 1;  VdbeBranchTaken(2,3);
  }
  break;
}

/* Opcode: And P1 P2 P3 * *
** Synopsis: r[P3]=(r[P1] && r[P2])
**

  }
  break;
}

/* Opcode: Once P1 P2 * * *
**
** Check if OP_Once flag P1 is set. If so, jump to instruction P2. Otherwise,
** set the flag and fall through to the next instruction.  In other words,
** this opcode causes all following up codes up through P2 (but not including
** P2) to run just once and skipped on subsequent times through the loop.
*/
case OP_Once: {             /* jump */
  assert( pOp->p1<p->nOnceFlag );
  VdbeBranchTaken(p->aOnceFlag[pOp->p1]!=0, 2);
  if( p->aOnceFlag[pOp->p1] ){
    pc = pOp->p2-1;
  }else{
    p->aOnceFlag[pOp->p1] = 1;
  }
  break;
}

#ifdef SQLITE_OMIT_FLOATING_POINT
    c = sqlite3VdbeIntValue(pIn1)!=0;
#else
    c = sqlite3VdbeRealValue(pIn1)!=0.0;
#endif
    if( pOp->opcode==OP_IfNot ) c = !c;
  }
  VdbeBranchTaken(c!=0, 2);
  if( c ){
    pc = pOp->p2-1;
  }
  break;
}

/* Opcode: IsNull P1 P2 * * *
** Synopsis:  if r[P1]==NULL goto P2
**
** Jump to P2 if the value in register P1 is NULL.
*/
case OP_IsNull: {            /* same as TK_ISNULL, jump, in1 */
  pIn1 = &aMem[pOp->p1];
  VdbeBranchTaken( (pIn1->flags & MEM_Null)!=0, 2);
  if( (pIn1->flags & MEM_Null)!=0 ){
    pc = pOp->p2 - 1;
  }
  break;
}

/* Opcode: NotNull P1 P2 * * *
** Synopsis: if r[P1]!=NULL goto P2
**
** Jump to P2 if the value in register P1 is not NULL.  
*/
case OP_NotNull: {            /* same as TK_NOTNULL, jump, in1 */
  pIn1 = &aMem[pOp->p1];
  VdbeBranchTaken( (pIn1->flags & MEM_Null)==0, 2);
  if( (pIn1->flags & MEM_Null)==0 ){
    pc = pOp->p2 - 1;
  }
  break;
}

/* Opcode: Column P1 P2 P3 P4 P5

  rc = sqlite3VdbeCursorMoveto(pC);
  if( rc ) goto abort_due_to_error;
  if( pC->cacheStatus!=p->cacheCtr || (pOp->p5&OPFLAG_CLEARCACHE)!=0 ){
    if( pC->nullRow ){
      if( pCrsr==0 ){
        assert( pC->pseudoTableReg>0 );
        pReg = &aMem[pC->pseudoTableReg];





        assert( pReg->flags & MEM_Blob );
        assert( memIsValid(pReg) );
        pC->payloadSize = pC->szRow = avail = pReg->n;
        pC->aRow = (u8*)pReg->z;
      }else{
        MemSetTypeFlag(pDest, MEM_Null);
        goto op_column_out;

  /* Extract the content for the p2+1-th column.  Control can only
  ** reach this point if aOffset[p2], aOffset[p2+1], and aType[p2] are
  ** all valid.
  */
  assert( p2<pC->nHdrParsed );
  assert( rc==SQLITE_OK );
  assert( sqlite3VdbeCheckMemInvariants(pDest) );
  if( pC->szRow>=aOffset[p2+1] ){
    /* This is the common case where the desired content fits on the original
    ** page - where the content is not on an overflow page */
    VdbeMemRelease(pDest);
    sqlite3VdbeSerialGet(pC->aRow+aOffset[p2], aType[p2], pDest);
  }else{
    /* This branch happens only when content is on overflow pages */

    sqlite3VdbeSerialGet(zData, t, pDest);
    /* If we dynamically allocated space to hold the data (in the
    ** sqlite3VdbeMemFromBtree() call above) then transfer control of that
    ** dynamically allocated space over to the pDest structure.
    ** This prevents a memory copy. */
    if( sMem.zMalloc ){
      assert( sMem.z==sMem.zMalloc );
      assert( VdbeMemDynamic(pDest)==0 );
      assert( (pDest->flags & (MEM_Blob|MEM_Str))==0 || pDest->z==sMem.z );
      pDest->flags &= ~(MEM_Ephem|MEM_Static);
      pDest->flags |= MEM_Term;
      pDest->z = sMem.z;
      pDest->zMalloc = sMem.zMalloc;
    }
  }
  pDest->enc = encoding;

  zAffinity = pOp->p4.z;
  assert( zAffinity!=0 );
  assert( zAffinity[pOp->p2]==0 );
  pIn1 = &aMem[pOp->p1];
  while( (cAff = *(zAffinity++))!=0 ){
    assert( pIn1 <= &p->aMem[(p->nMem-p->nCursor)] );
    assert( memIsValid(pIn1) );

    applyAffinity(pIn1, cAff, encoding);
    pIn1++;
  }
  break;
}

/* Opcode: MakeRecord P1 P2 P3 P4 *

  /* Apply the requested affinity to all inputs
  */
  assert( pData0<=pLast );
  if( zAffinity ){
    pRec = pData0;
    do{
      applyAffinity(pRec++, *(zAffinity++), encoding);
      assert( zAffinity[0]==0 || pRec<=pLast );
    }while( zAffinity[0] );
  }

  /* Loop through the elements that will make up the record to figure
  ** out how much space is required for the new record.
  */
  pRec = pLast;
  do{

    j += sqlite3VdbeSerialPut(&zNewRecord[j], pRec, serial_type); /* content */
  }while( (++pRec)<=pLast );
  assert( i==nHdr );
  assert( j==nByte );

  assert( pOp->p3>0 && pOp->p3<=(p->nMem-p->nCursor) );
  pOut->n = (int)nByte;
  pOut->flags = MEM_Blob;
  pOut->xDel = 0;
  if( nZero ){
    pOut->u.nZero = nZero;
    pOut->flags |= MEM_Zero;
  }
  pOut->enc = SQLITE_UTF8;  /* In case the blob is ever converted to text */
  REGISTER_TRACE(pOp->p3, pOut);

                   "cannot commit - no transaction is active"));
         
    rc = SQLITE_ERROR;
  }
  break;
}

/* Opcode: Transaction P1 P2 P3 P4 P5
**
** Begin a transaction on database P1 if a transaction is not already
** active.
** If P2 is non-zero, then a write-transaction is started, or if a 
** read-transaction is already active, it is upgraded to a write-transaction.
** If P2 is zero, then a read-transaction is started.
**
** P1 is the index of the database file on which the transaction is
** started.  Index 0 is the main database file and index 1 is the
** file used for temporary tables.  Indices of 2 or more are used for
** attached databases.
**








** If a write-transaction is started and the Vdbe.usesStmtJournal flag is
** true (this flag is set if the Vdbe may modify more than one row and may
** throw an ABORT exception), a statement transaction may also be opened.
** More specifically, a statement transaction is opened iff the database
** connection is currently not in autocommit mode, or if there are other
** active statements. A statement transaction allows the changes made by this
** VDBE to be rolled back after an error without having to roll back the
** entire transaction. If no error is encountered, the statement transaction
** will automatically commit when the VDBE halts.
**
** If P5!=0 then this opcode also checks the schema cookie against P3
** and the schema generation counter against P4.
** The cookie changes its value whenever the database schema changes.
** This operation is used to detect when that the cookie has changed
** and that the current process needs to reread the schema.  If the schema
** cookie in P3 differs from the schema cookie in the database header or
** if the schema generation counter in P4 differs from the current
** generation counter, then an SQLITE_SCHEMA error is raised and execution
** halts.  The sqlite3_step() wrapper function might then reprepare the
** statement and rerun it from the beginning.
*/
case OP_Transaction: {
  Btree *pBt;
  int iMeta;
  int iGen;

  assert( p->bIsReader );
  assert( p->readOnly==0 || pOp->p2==0 );
  assert( pOp->p1>=0 && pOp->p1<db->nDb );
  assert( (p->btreeMask & (((yDbMask)1)<<pOp->p1))!=0 );
  if( pOp->p2 && (db->flags & SQLITE_QueryOnly)!=0 ){
    rc = SQLITE_READONLY;

      /* Store the current value of the database handles deferred constraint
      ** counter. If the statement transaction needs to be rolled back,
      ** the value of this counter needs to be restored too.  */
      p->nStmtDefCons = db->nDeferredCons;
      p->nStmtDefImmCons = db->nDeferredImmCons;
    }

    /* Gather the schema version number for checking */
    sqlite3BtreeGetMeta(pBt, BTREE_SCHEMA_VERSION, (u32 *)&iMeta);
    iGen = db->aDb[pOp->p1].pSchema->iGeneration;
  }else{
    iGen = iMeta = 0;
  }
  assert( pOp->p5==0 || pOp->p4type==P4_INT32 );
  if( pOp->p5 && (iMeta!=pOp->p3 || iGen!=pOp->p4.i) ){
    sqlite3DbFree(db, p->zErrMsg);
    p->zErrMsg = sqlite3DbStrDup(db, "database schema has changed");
    /* If the schema-cookie from the database file matches the cookie 
    ** stored with the in-memory representation of the schema, do
    ** not reload the schema from the database file.
    **
    ** If virtual-tables are in use, this is not just an optimization.
    ** Often, v-tables store their data in other SQLite tables, which
    ** are queried from within xNext() and other v-table methods using
    ** prepared queries. If such a query is out-of-date, we do not want to
    ** discard the database schema, as the user code implementing the
    ** v-table would have to be ready for the sqlite3_vtab structure itself
    ** to be invalidated whenever sqlite3_step() is called from within 
    ** a v-table method.
    */
    if( db->aDb[pOp->p1].pSchema->schema_cookie!=iMeta ){
      sqlite3ResetOneSchema(db, pOp->p1);
    }
    p->expired = 1;
    rc = SQLITE_SCHEMA;
  }
  break;
}

/* Opcode: ReadCookie P1 P2 P3 * *
**
** Read cookie number P3 from database P1 and write it into register P2.

  }
  if( pOp->p1==1 ){
    /* Invalidate all prepared statements whenever the TEMP database
    ** schema is changed.  Ticket #1644 */
    sqlite3ExpirePreparedStatements(db);
    p->expired = 0;
  }




























































  break;
}

/* Opcode: OpenRead P1 P2 P3 P4 P5
** Synopsis: root=P2 iDb=P3
**
** Open a read-only cursor for the database table whose root page is

      pCx->isTable = 1;
    }
  }
  pCx->isOrdered = (pOp->p5!=BTREE_UNORDERED);
  break;
}

/* Opcode: SorterOpen P1 P2 * P4 *
**
** This opcode works like OP_OpenEphemeral except that it opens
** a transient index that is specifically designed to sort large
** tables using an external merge-sort algorithm.
*/
case OP_SorterOpen: {
  VdbeCursor *pCx;

  assert( pOp->p1>=0 );
  assert( pOp->p2>=0 );
  pCx = allocateCursor(p, pOp->p1, pOp->p2, -1, 1);
  if( pCx==0 ) goto no_mem;
  pCx->pKeyInfo = pOp->p4.pKeyInfo;
  assert( pCx->pKeyInfo->db==db );
  assert( pCx->pKeyInfo->enc==ENC(db) );
  rc = sqlite3VdbeSorterInit(db, pCx);
  break;
}

/* Opcode: OpenPseudo P1 P2 P3 * *
** Synopsis: P3 columns in r[P2]
**
** Open a new cursor that points to a fake table that contains a single
** row of data.  The content of that one row is the content of memory
** register P2.  In other words, cursor P1 becomes an alias for the 
** MEM_Blob content contained in register P2.

**
** A pseudo-table created by this opcode is used to hold a single
** row output from the sorter so that the row can be decomposed into
** individual columns using the OP_Column opcode.  The OP_Column opcode
** is the only cursor opcode that works with a pseudo-table.
**
** P3 is the number of fields in the records that will be stored by
** the pseudo-table.
*/
case OP_OpenPseudo: {
  VdbeCursor *pCx;

  assert( pOp->p1>=0 );
  assert( pOp->p3>=0 );
  pCx = allocateCursor(p, pOp->p1, pOp->p3, -1, 0);
  if( pCx==0 ) goto no_mem;
  pCx->nullRow = 1;
  pCx->pseudoTableReg = pOp->p2;
  pCx->isTable = 1;
  assert( pOp->p5==0 );
  break;
}

/* Opcode: Close P1 * * * *
**
** Close a cursor previously opened as P1.  If P1 is not
** currently open, this instruction is a no-op.

**
** Reposition cursor P1 so that it points to the largest entry that 
** is less than or equal to the key value. If there are no records 
** less than or equal to the key and P2 is not zero, then jump to P2.
**
** See also: Found, NotFound, Distinct, SeekGt, SeekGe, SeekLt
*/
case OP_SeekLT:         /* jump, in3 */
case OP_SeekLE:         /* jump, in3 */
case OP_SeekGE:         /* jump, in3 */
case OP_SeekGT: {       /* jump, in3 */
  int res;
  int oc;
  VdbeCursor *pC;
  UnpackedRecord r;
  int nField;
  i64 iKey;      /* The rowid we are to seek to */

  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  assert( pOp->p2!=0 );
  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );
  assert( pC->pseudoTableReg==0 );
  assert( OP_SeekLE == OP_SeekLT+1 );
  assert( OP_SeekGE == OP_SeekLT+2 );
  assert( OP_SeekGT == OP_SeekLT+3 );
  assert( pC->isOrdered );
  assert( pC->pCursor!=0 );
  oc = pOp->opcode;
  pC->nullRow = 0;
  if( pC->isTable ){
    /* The input value in P3 might be of any type: integer, real, string,
    ** blob, or NULL.  But it needs to be an integer before we can do
    ** the seek, so covert it. */
    pIn3 = &aMem[pOp->p3];
    applyNumericAffinity(pIn3);
    iKey = sqlite3VdbeIntValue(pIn3);
    pC->rowidIsValid = 0;

    /* If the P3 value could not be converted into an integer without
    ** loss of information, then special processing is required... */
    if( (pIn3->flags & MEM_Int)==0 ){
      if( (pIn3->flags & MEM_Real)==0 ){
        /* If the P3 value cannot be converted into any kind of a number,
        ** then the seek is not possible, so jump to P2 */
        pc = pOp->p2 - 1;  VdbeBranchTaken(1,2);
        break;
      }

      /* If the approximation iKey is larger than the actual real search
      ** term, substitute >= for > and < for <=. e.g. if the search term
      ** is 4.9 and the integer approximation 5:
      **
      **        (x >  4.9)    ->     (x >= 5)
      **        (x <= 4.9)    ->     (x <  5)
      */
      if( pIn3->r<(double)iKey ){
        assert( OP_SeekGE==(OP_SeekGT-1) );
        assert( OP_SeekLT==(OP_SeekLE-1) );
        assert( (OP_SeekLE & 0x0001)==(OP_SeekGT & 0x0001) );
        if( (oc & 0x0001)==(OP_SeekGT & 0x0001) ) oc--;
      }

      /* If the approximation iKey is smaller than the actual real search
      ** term, substitute <= for < and > for >=.  */
      else if( pIn3->r>(double)iKey ){
        assert( OP_SeekLE==(OP_SeekLT+1) );
        assert( OP_SeekGT==(OP_SeekGE+1) );
        assert( (OP_SeekLT & 0x0001)==(OP_SeekGE & 0x0001) );
        if( (oc & 0x0001)==(OP_SeekLT & 0x0001) ) oc++;
      }
    } 
    rc = sqlite3BtreeMovetoUnpacked(pC->pCursor, 0, (u64)iKey, 0, &res);
    if( rc!=SQLITE_OK ){
      goto abort_due_to_error;
    }
    if( res==0 ){
      pC->rowidIsValid = 1;
      pC->lastRowid = iKey;
    }
  }else{
    nField = pOp->p4.i;
    assert( pOp->p4type==P4_INT32 );
    assert( nField>0 );
    r.pKeyInfo = pC->pKeyInfo;
    r.nField = (u16)nField;

    /* The next line of code computes as follows, only faster:
    **   if( oc==OP_SeekGT || oc==OP_SeekLE ){
    **     r.default_rc = -1;
    **   }else{
    **     r.default_rc = +1;
    **   }
    */
    r.default_rc = ((1 & (oc - OP_SeekLT)) ? -1 : +1);
    assert( oc!=OP_SeekGT || r.default_rc==-1 );
    assert( oc!=OP_SeekLE || r.default_rc==-1 );
    assert( oc!=OP_SeekGE || r.default_rc==+1 );
    assert( oc!=OP_SeekLT || r.default_rc==+1 );

    r.aMem = &aMem[pOp->p3];
#ifdef SQLITE_DEBUG
    { int i; for(i=0; i<r.nField; i++) assert( memIsValid(&r.aMem[i]) ); }
#endif
    ExpandBlob(r.aMem);
    rc = sqlite3BtreeMovetoUnpacked(pC->pCursor, &r, 0, 0, &res);
    if( rc!=SQLITE_OK ){
      goto abort_due_to_error;
    }
    pC->rowidIsValid = 0;
  }
  pC->deferredMoveto = 0;
  pC->cacheStatus = CACHE_STALE;
#ifdef SQLITE_TEST
  sqlite3_search_count++;
#endif
  if( oc>=OP_SeekGE ){  assert( oc==OP_SeekGE || oc==OP_SeekGT );
    if( res<0 || (res==0 && oc==OP_SeekGT) ){
      res = 0;
      rc = sqlite3BtreeNext(pC->pCursor, &res);
      if( rc!=SQLITE_OK ) goto abort_due_to_error;
      pC->rowidIsValid = 0;
    }else{
      res = 0;
    }
  }else{
    assert( oc==OP_SeekLT || oc==OP_SeekLE );
    if( res>0 || (res==0 && oc==OP_SeekLT) ){
      res = 0;
      rc = sqlite3BtreePrevious(pC->pCursor, &res);
      if( rc!=SQLITE_OK ) goto abort_due_to_error;
      pC->rowidIsValid = 0;
    }else{
      /* res might be negative because the table is empty.  Check to
      ** see if this is the case.
      */
      res = sqlite3BtreeEof(pC->pCursor);
    }
  }
  assert( pOp->p2>0 );
  VdbeBranchTaken(res!=0,2);
  if( res ){
    pc = pOp->p2 - 1;
  }
  break;
}

/* Opcode: Seek P1 P2 * * *

  assert( pC->pCursor!=0 );
  assert( pC->isTable==0 );
  pFree = 0;  /* Not needed.  Only used to suppress a compiler warning. */
  if( pOp->p4.i>0 ){
    r.pKeyInfo = pC->pKeyInfo;
    r.nField = (u16)pOp->p4.i;
    r.aMem = pIn3;



    for(ii=0; ii<r.nField; ii++){
      assert( memIsValid(&r.aMem[ii]) );
      ExpandBlob(&r.aMem[ii]);
#ifdef SQLITE_DEBUG
      if( ii ) REGISTER_TRACE(pOp->p3+ii, &r.aMem[ii]);


#endif

    }
    pIdxKey = &r;
  }else{
    pIdxKey = sqlite3VdbeAllocUnpackedRecord(
        pC->pKeyInfo, aTempRec, sizeof(aTempRec), &pFree
    ); 
    if( pIdxKey==0 ) goto no_mem;
    assert( pIn3->flags & MEM_Blob );
    assert( (pIn3->flags & MEM_Zero)==0 );  /* zeroblobs already expanded */
    sqlite3VdbeRecordUnpack(pC->pKeyInfo, pIn3->n, pIn3->z, pIdxKey);

  }
  pIdxKey->default_rc = 0;
  if( pOp->opcode==OP_NoConflict ){
    /* For the OP_NoConflict opcode, take the jump if any of the
    ** input fields are NULL, since any key with a NULL will not
    ** conflict */
    for(ii=0; ii<r.nField; ii++){
      if( r.aMem[ii].flags & MEM_Null ){
        pc = pOp->p2 - 1; VdbeBranchTaken(1,2);
        break;
      }
    }
  }
  rc = sqlite3BtreeMovetoUnpacked(pC->pCursor, pIdxKey, 0, 0, &res);
  if( pOp->p4.i==0 ){
    sqlite3DbFree(db, pFree);
  }
  if( rc!=SQLITE_OK ){
    break;
  }
  pC->seekResult = res;
  alreadyExists = (res==0);
  pC->nullRow = 1-alreadyExists;
  pC->deferredMoveto = 0;
  pC->cacheStatus = CACHE_STALE;
  if( pOp->opcode==OP_Found ){
    VdbeBranchTaken(alreadyExists!=0,2);
    if( alreadyExists ) pc = pOp->p2 - 1;
  }else{
    VdbeBranchTaken(alreadyExists==0,2);
    if( !alreadyExists ) pc = pOp->p2 - 1;
  }
  break;
}

/* Opcode: NotExists P1 P2 P3 * *
** Synopsis: intkey=r[P3]

  iKey = pIn3->u.i;
  rc = sqlite3BtreeMovetoUnpacked(pCrsr, 0, iKey, 0, &res);
  pC->lastRowid = pIn3->u.i;
  pC->rowidIsValid = res==0 ?1:0;
  pC->nullRow = 0;
  pC->cacheStatus = CACHE_STALE;
  pC->deferredMoveto = 0;
  VdbeBranchTaken(res!=0,2);
  if( res!=0 ){
    pc = pOp->p2 - 1;
    assert( pC->rowidIsValid==0 );
  }
  pC->seekResult = res;
  break;
}

    ** Others complain about 0x7ffffffffffffffffLL.  The following macro seems
    ** to provide the constant while making all compilers happy.
    */
#   define MAX_ROWID  (i64)( (((u64)0x7fffffff)<<32) | (u64)0xffffffff )
#endif

    if( !pC->useRandomRowid ){


      rc = sqlite3BtreeLast(pC->pCursor, &res);
      if( rc!=SQLITE_OK ){
        goto abort_due_to_error;
      }
      if( res ){
        v = 1;   /* IMP: R-61914-48074 */
      }else{
        assert( sqlite3BtreeCursorIsValid(pC->pCursor) );
        rc = sqlite3BtreeKeySize(pC->pCursor, &v);
        assert( rc==SQLITE_OK );   /* Cannot fail following BtreeLast() */
        if( v>=MAX_ROWID ){
          pC->useRandomRowid = 1;
        }else{
          v++;   /* IMP: R-29538-34987 */
        }
      }
    }

#ifndef SQLITE_OMIT_AUTOINCREMENT
    if( pOp->p3 ){
      /* Assert that P3 is a valid memory cell. */
      assert( pOp->p3>0 );
      if( p->pFrame ){
        for(pFrame=p->pFrame; pFrame->pParent; pFrame=pFrame->pParent);
        /* Assert that P3 is a valid memory cell. */
        assert( pOp->p3<=pFrame->nMem );
        pMem = &pFrame->aMem[pOp->p3];
      }else{
        /* Assert that P3 is a valid memory cell. */
        assert( pOp->p3<=(p->nMem-p->nCursor) );
        pMem = &aMem[pOp->p3];
        memAboutToChange(p, pMem);
      }
      assert( memIsValid(pMem) );

      REGISTER_TRACE(pOp->p3, pMem);
      sqlite3VdbeMemIntegerify(pMem);
      assert( (pMem->flags & MEM_Int)!=0 );  /* mem(P3) holds an integer */
      if( pMem->u.i==MAX_ROWID || pC->useRandomRowid ){
        rc = SQLITE_FULL;   /* IMP: R-12275-61338 */
        goto abort_due_to_error;
      }
      if( v<pMem->u.i+1 ){
        v = pMem->u.i + 1;
      }
      pMem->u.i = v;
    }
#endif



    if( pC->useRandomRowid ){
      /* IMPLEMENTATION-OF: R-07677-41881 If the largest ROWID is equal to the
      ** largest possible integer (9223372036854775807) then the database
      ** engine starts picking positive candidate ROWIDs at random until
      ** it finds one that is not previously used. */
      assert( pOp->p3==0 );  /* We cannot be in random rowid mode if this is
                             ** an AUTOINCREMENT table. */

  }
  seekResult = ((pOp->p5 & OPFLAG_USESEEKRESULT) ? pC->seekResult : 0);
  if( pData->flags & MEM_Zero ){
    nZero = pData->u.nZero;
  }else{
    nZero = 0;
  }

  rc = sqlite3BtreeInsert(pC->pCursor, 0, iKey,
                          pData->z, pData->n, nZero,
                          (pOp->p5 & OPFLAG_APPEND)!=0, seekResult
  );
  pC->rowidIsValid = 0;
  pC->deferredMoveto = 0;
  pC->cacheStatus = CACHE_STALE;

  ** below is always a no-op and cannot fail.  We will run it anyhow, though,
  ** to guard against future changes to the code generator.
  **/
  assert( pC->deferredMoveto==0 );
  rc = sqlite3VdbeCursorMoveto(pC);
  if( NEVER(rc!=SQLITE_OK) ) goto abort_due_to_error;


  rc = sqlite3BtreeDelete(pC->pCursor);
  pC->cacheStatus = CACHE_STALE;

  /* Invoke the update-hook if required. */
  if( rc==SQLITE_OK && db->xUpdateCallback && pOp->p4.z && pC->isTable ){
    db->xUpdateCallback(db->pUpdateArg, SQLITE_DELETE,
                        db->aDb[pC->iDb].zName, pOp->p4.z, iKey);

  pC = p->apCsr[pOp->p1];
  assert( isSorter(pC) );
  assert( pOp->p4type==P4_INT32 );
  pIn3 = &aMem[pOp->p3];
  nIgnore = pOp->p4.i;
  rc = sqlite3VdbeSorterCompare(pC, pIn3, nIgnore, &res);
  VdbeBranchTaken(res!=0,2);
  if( res ){
    pc = pOp->p2-1;
  }
  break;
};

/* Opcode: SorterData P1 P2 * * *

** of a real table, not a pseudo-table.
*/
/* Opcode: RowKey P1 P2 * * *
** Synopsis: r[P2]=key
**
** Write into register P2 the complete row key for cursor P1.
** There is no interpretation of the data.  
** The key is copied onto the P2 register exactly as 
** it is found in the database file.
**
** If the P1 cursor must be pointing to a valid row (not a NULL row)
** of a real table, not a pseudo-table.
*/
case OP_RowKey:
case OP_RowData: {

  res = 0;
  assert( pCrsr!=0 );
  rc = sqlite3BtreeLast(pCrsr, &res);
  pC->nullRow = (u8)res;
  pC->deferredMoveto = 0;
  pC->rowidIsValid = 0;
  pC->cacheStatus = CACHE_STALE;
  if( pOp->p2>0 ){
    VdbeBranchTaken(res!=0,2);
    if( res ) pc = pOp->p2 - 1;
  }
  break;
}


/* Opcode: Sort P1 P2 * * *
**

    rc = sqlite3BtreeFirst(pCrsr, &res);
    pC->deferredMoveto = 0;
    pC->cacheStatus = CACHE_STALE;
    pC->rowidIsValid = 0;
  }
  pC->nullRow = (u8)res;
  assert( pOp->p2>0 && pOp->p2<p->nOp );
  VdbeBranchTaken(res!=0,2);
  if( res ){
    pc = pOp->p2 - 1;
  }
  break;
}

/* Opcode: Next P1 P2 P3 P4 P5
**
** Advance cursor P1 so that it points to the next key/data pair in its
** table or index.  If there are no more key/value pairs then fall through
** to the following instruction.  But if the cursor advance was successful,
** jump immediately to P2.
**
** The P1 cursor must be for a real table, not a pseudo-table.  P1 must have
** been opened prior to this opcode or the program will segfault.
**
** The P3 value is a hint to the btree implementation. If P3==1, that
** means P1 is an SQL index and that this instruction could have been
** omitted if that index had been unique.  P3 is usually 0.  P3 is
** always either 0 or 1.
**
** P4 is always of type P4_ADVANCE. The function pointer points to
** sqlite3BtreeNext().
**
** If P5 is positive and the jump is taken, then event counter
** number P5-1 in the prepared statement is incremented.
**
** See also: Prev, NextIfOpen
*/
/* Opcode: NextIfOpen P1 P2 P3 P4 P5
**
** This opcode works just like OP_Next except that if cursor P1 is not
** open it behaves a no-op.
*/
/* Opcode: Prev P1 P2 P3 P4 P5
**
** Back up cursor P1 so that it points to the previous key/data pair in its
** table or index.  If there is no previous key/value pairs then fall through
** to the following instruction.  But if the cursor backup was successful,
** jump immediately to P2.
**
** The P1 cursor must be for a real table, not a pseudo-table.  If P1 is
** not open then the behavior is undefined.
**
** The P3 value is a hint to the btree implementation. If P3==1, that
** means P1 is an SQL index and that this instruction could have been
** omitted if that index had been unique.  P3 is usually 0.  P3 is
** always either 0 or 1.
**
** P4 is always of type P4_ADVANCE. The function pointer points to
** sqlite3BtreePrevious().
**
** If P5 is positive and the jump is taken, then event counter
** number P5-1 in the prepared statement is incremented.
*/
/* Opcode: PrevIfOpen P1 P2 P3 P4 P5
**
** This opcode works just like OP_Prev except that if cursor P1 is not
** open it behaves a no-op.
*/
case OP_SorterNext: {  /* jump */
  VdbeCursor *pC;
  int res;

  if( p->apCsr[pOp->p1]==0 ) break;
  /* Fall through */
case OP_Prev:          /* jump */
case OP_Next:          /* jump */
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  assert( pOp->p5<ArraySize(p->aCounter) );
  pC = p->apCsr[pOp->p1];
  res = pOp->p3;
  assert( pC!=0 );
  assert( pC->deferredMoveto==0 );
  assert( pC->pCursor );
  assert( res==0 || (res==1 && pC->isTable==0) );
  testcase( res==1 );
  assert( pOp->opcode!=OP_Next || pOp->p4.xAdvance==sqlite3BtreeNext );
  assert( pOp->opcode!=OP_Prev || pOp->p4.xAdvance==sqlite3BtreePrevious );
  assert( pOp->opcode!=OP_NextIfOpen || pOp->p4.xAdvance==sqlite3BtreeNext );
  assert( pOp->opcode!=OP_PrevIfOpen || pOp->p4.xAdvance==sqlite3BtreePrevious);
  rc = pOp->p4.xAdvance(pC->pCursor, &res);
next_tail:
  pC->cacheStatus = CACHE_STALE;
  VdbeBranchTaken(res==0,2);
  if( res==0 ){
    pC->nullRow = 0;
    pc = pOp->p2 - 1;
    p->aCounter[pOp->p5]++;
#ifdef SQLITE_TEST
    sqlite3_search_count++;
#endif

**
** Register P2 holds an SQL index key made using the
** MakeRecord instructions.  This opcode writes that key
** into the index P1.  Data for the entry is nil.
**
** P3 is a flag that provides a hint to the b-tree layer that this
** insert is likely to be an append.
**
** If P5 has the OPFLAG_NCHANGE bit set, then the change counter is
** incremented by this instruction.  If the OPFLAG_NCHANGE bit is clear,
** then the change counter is unchanged.
**
** If P5 has the OPFLAG_USESEEKRESULT bit set, then the cursor must have
** just done a seek to the spot where the new entry is to be inserted.
** This flag avoids doing an extra seek.
**
** This instruction only works for indices.  The equivalent instruction
** for tables is OP_Insert.
*/
case OP_SorterInsert:       /* in2 */
case OP_IdxInsert: {        /* in2 */
  VdbeCursor *pC;

  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );
  pCrsr = pC->pCursor;
  assert( pCrsr!=0 );
  assert( pOp->p5==0 );
  r.pKeyInfo = pC->pKeyInfo;
  r.nField = (u16)pOp->p3;
  r.default_rc = 0;
  r.aMem = &aMem[pOp->p2];
#ifdef SQLITE_DEBUG
  { int i; for(i=0; i<r.nField; i++) assert( memIsValid(&r.aMem[i]) ); }
#endif
  rc = sqlite3BtreeMovetoUnpacked(pCrsr, &r, 0, 0, &res);
  if( rc==SQLITE_OK && res==0 ){
    rc = sqlite3BtreeDelete(pCrsr);

  break;
}

/* Opcode: IdxGE P1 P2 P3 P4 P5
** Synopsis: key=r[P3@P4]
**
** The P4 register values beginning with P3 form an unpacked index 
** key that omits the PRIMARY KEY.  Compare this key value against the index 
** that P1 is currently pointing to, ignoring the PRIMARY KEY or ROWID 
** fields at the end.
**
** If the P1 index entry is greater than or equal to the key value
** then jump to P2.  Otherwise fall through to the next instruction.
*/
/* Opcode: IdxGT P1 P2 P3 P4 P5
** Synopsis: key=r[P3@P4]
**
** The P4 register values beginning with P3 form an unpacked index 
** key that omits the PRIMARY KEY.  Compare this key value against the index 
** that P1 is currently pointing to, ignoring the PRIMARY KEY or ROWID 
** fields at the end.
**
** If the P1 index entry is greater than the key value


** then jump to P2.  Otherwise fall through to the next instruction.
*/
/* Opcode: IdxLT P1 P2 P3 P4 P5
** Synopsis: key=r[P3@P4]
**
** The P4 register values beginning with P3 form an unpacked index 
** key that omits the PRIMARY KEY or ROWID.  Compare this key value against
** the index that P1 is currently pointing to, ignoring the PRIMARY KEY or
** ROWID on the P1 index.
**
** If the P1 index entry is less than the key value then jump to P2.
** Otherwise fall through to the next instruction.
*/
/* Opcode: IdxLE P1 P2 P3 P4 P5
** Synopsis: key=r[P3@P4]
**
** The P4 register values beginning with P3 form an unpacked index 
** key that omits the PRIMARY KEY or ROWID.  Compare this key value against
** the index that P1 is currently pointing to, ignoring the PRIMARY KEY or
** ROWID on the P1 index.
**
** If the P1 index entry is less than or equal to the key value then jump
** to P2. Otherwise fall through to the next instruction.
*/
case OP_IdxLE:          /* jump */
case OP_IdxGT:          /* jump */
case OP_IdxLT:          /* jump */
case OP_IdxGE:  {       /* jump */
  VdbeCursor *pC;
  int res;
  UnpackedRecord r;

  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );
  assert( pC->isOrdered );
  assert( pC->pCursor!=0);
  assert( pC->deferredMoveto==0 );
  assert( pOp->p5==0 || pOp->p5==1 );
  assert( pOp->p4type==P4_INT32 );
  r.pKeyInfo = pC->pKeyInfo;
  r.nField = (u16)pOp->p4.i;
  if( pOp->opcode<OP_IdxLT ){
    assert( pOp->opcode==OP_IdxLE || pOp->opcode==OP_IdxGT );
    r.default_rc = -1;
  }else{
    assert( pOp->opcode==OP_IdxGE || pOp->opcode==OP_IdxLT );
    r.default_rc = 0;
  }
  r.aMem = &aMem[pOp->p3];
#ifdef SQLITE_DEBUG
  { int i; for(i=0; i<r.nField; i++) assert( memIsValid(&r.aMem[i]) ); }
#endif
  res = 0;  /* Not needed.  Only used to silence a warning. */
  rc = sqlite3VdbeIdxKeyCompare(pC, &r, &res);
  assert( (OP_IdxLE&1)==(OP_IdxLT&1) && (OP_IdxGE&1)==(OP_IdxGT&1) );
  if( (pOp->opcode&1)==(OP_IdxLT&1) ){
    assert( pOp->opcode==OP_IdxLE || pOp->opcode==OP_IdxLT );
    res = -res;
  }else{
    assert( pOp->opcode==OP_IdxGE || pOp->opcode==OP_IdxGT );
    res++;
  }
  VdbeBranchTaken(res>0,2);
  if( res>0 ){
    pc = pOp->p2 - 1 ;
  }
  break;
}

/* Opcode: Destroy P1 P2 P3 * *

** See also: Destroy
*/
case OP_Clear: {
  int nChange;
 
  nChange = 0;
  assert( p->readOnly==0 );

  assert( (p->btreeMask & (((yDbMask)1)<<pOp->p2))!=0 );
  rc = sqlite3BtreeClearTable(
      db->aDb[pOp->p2].pBt, pOp->p1, (pOp->p3 ? &nChange : 0)
  );
  if( pOp->p3 ){
    p->nChange += nChange;
    if( pOp->p3>0 ){

  pIn1 = &aMem[pOp->p1];
  if( (pIn1->flags & MEM_RowSet)==0 
   || sqlite3RowSetNext(pIn1->u.pRowSet, &val)==0
  ){
    /* The boolean index is empty */
    sqlite3VdbeMemSetNull(pIn1);
    pc = pOp->p2 - 1;
    VdbeBranchTaken(1,2);
  }else{
    /* A value was pulled from the index */
    sqlite3VdbeMemSetInt64(&aMem[pOp->p3], val);
    VdbeBranchTaken(0,2);
  }
  goto check_for_interrupt;
}

/* Opcode: RowSetTest P1 P2 P3 P4
** Synopsis: if r[P3] in rowset(P1) goto P2
**

  assert( pOp->p4type==P4_INT32 );
  assert( iSet==-1 || iSet>=0 );
  if( iSet ){
    exists = sqlite3RowSetTest(pIn1->u.pRowSet, 
                               (u8)(iSet>=0 ? iSet & 0xf : 0xff),
                               pIn3->u.i);
    VdbeBranchTaken(exists!=0,2);
    if( exists ){
      pc = pOp->p2 - 1;
      break;
    }
  }
  if( iSet>=0 ){
    sqlite3RowSetInsert(pIn1->u.pRowSet, pIn3->u.i);
  }
  break;
}


#ifndef SQLITE_OMIT_TRIGGER

/* Opcode: Program P1 P2 P3 P4 P5
**
** Execute the trigger program passed as P4 (type P4_SUBPROGRAM). 
**
** P1 contains the address of the memory cell that contains the first memory 
** cell in an array of values used as arguments to the sub-program. P2 
** contains the address to jump to if the sub-program throws an IGNORE 
** exception using the RAISE() function. Register P3 contains the address 
** of a memory cell in this (the parent) VM that is used to allocate the 
** memory required by the sub-vdbe at runtime.
**
** P4 is a pointer to the VM containing the trigger program.
**
** If P5 is non-zero, then recursive program invocation is enabled.
*/
case OP_Program: {        /* jump */
  int nMem;               /* Number of memory registers for sub-program */
  int nByte;              /* Bytes of runtime space required for sub-program */
  Mem *pRt;               /* Register to allocate runtime space */
  Mem *pMem;              /* Used to iterate through memory cells */
  Mem *pEnd;              /* Last memory cell in new array */

    pFrame->nOp = p->nOp;
    pFrame->token = pProgram->token;
    pFrame->aOnceFlag = p->aOnceFlag;
    pFrame->nOnceFlag = p->nOnceFlag;

    pEnd = &VdbeFrameMem(pFrame)[pFrame->nChildMem];
    for(pMem=VdbeFrameMem(pFrame); pMem!=pEnd; pMem++){
      pMem->flags = MEM_Undefined;
      pMem->db = db;
    }
  }else{
    pFrame = pRt->u.pFrame;
    assert( pProgram->nMem+pProgram->nCsr==pFrame->nChildMem );
    assert( pProgram->nCsr==pFrame->nChildCsr );
    assert( pc==pFrame->pc );

** If P1 is non-zero, then the jump is taken if the database constraint-counter
** is zero (the one that counts deferred constraint violations). If P1 is
** zero, the jump is taken if the statement constraint-counter is zero
** (immediate foreign key constraint violations).
*/
case OP_FkIfZero: {         /* jump */
  if( pOp->p1 ){
    VdbeBranchTaken(db->nDeferredCons==0 && db->nDeferredImmCons==0, 2);
    if( db->nDeferredCons==0 && db->nDeferredImmCons==0 ) pc = pOp->p2-1;
  }else{
    VdbeBranchTaken(p->nFkConstraint==0 && db->nDeferredImmCons==0, 2);
    if( p->nFkConstraint==0 && db->nDeferredImmCons==0 ) pc = pOp->p2-1;
  }
  break;
}
#endif /* #ifndef SQLITE_OMIT_FOREIGN_KEY */

#ifndef SQLITE_OMIT_AUTOINCREMENT

**
** It is illegal to use this instruction on a register that does
** not contain an integer.  An assertion fault will result if you try.
*/
case OP_IfPos: {        /* jump, in1 */
  pIn1 = &aMem[pOp->p1];
  assert( pIn1->flags&MEM_Int );
  VdbeBranchTaken( pIn1->u.i>0, 2);
  if( pIn1->u.i>0 ){
     pc = pOp->p2 - 1;
  }
  break;
}

/* Opcode: IfNeg P1 P2 * * *
** Synopsis: if r[P1]<0 goto P2
**
** If the value of register P1 is less than zero, jump to P2. 
**
** It is illegal to use this instruction on a register that does
** not contain an integer.  An assertion fault will result if you try.
*/
case OP_IfNeg: {        /* jump, in1 */
  pIn1 = &aMem[pOp->p1];
  assert( pIn1->flags&MEM_Int );
  VdbeBranchTaken(pIn1->u.i<0, 2);
  if( pIn1->u.i<0 ){
     pc = pOp->p2 - 1;
  }
  break;
}

/* Opcode: IfZero P1 P2 P3 * *
** Synopsis: r[P1]+=P3, if r[P1]==0 goto P2
**
** The register P1 must contain an integer.  Add literal P3 to the
** value in register P1.  If the result is exactly 0, jump to P2. 
**
** It is illegal to use this instruction on a register that does
** not contain an integer.  An assertion fault will result if you try.
*/
case OP_IfZero: {        /* jump, in1 */
  pIn1 = &aMem[pOp->p1];
  assert( pIn1->flags&MEM_Int );
  pIn1->u.i += pOp->p3;
  VdbeBranchTaken(pIn1->u.i==0, 2);
  if( pIn1->u.i==0 ){
     pc = pOp->p2 - 1;
  }
  break;
}

/* Opcode: AggStep * P2 P3 P4 P5

  pRec = &aMem[pOp->p2];
  apVal = p->apArg;
  assert( apVal || n==0 );
  for(i=0; i<n; i++, pRec++){
    assert( memIsValid(pRec) );
    apVal[i] = pRec;
    memAboutToChange(p, pRec);

  }
  ctx.pFunc = pOp->p4.pFunc;
  assert( pOp->p3>0 && pOp->p3<=(p->nMem-p->nCursor) );
  ctx.pMem = pMem = &aMem[pOp->p3];
  pMem->n++;
  ctx.s.flags = MEM_Null;
  ctx.s.z = 0;

    sqlite3VdbeMemSetInt64(pMem, (i64)aRes[i]);
  }    
  break;
};  
#endif

#ifndef SQLITE_OMIT_PRAGMA
/* Opcode: JournalMode P1 P2 P3 * *
**
** Change the journal mode of database P1 to P3. P3 must be one of the
** PAGER_JOURNALMODE_XXX values. If changing between the various rollback
** modes (delete, truncate, persist, off and memory), this is a simple
** operation. No IO is required.
**
** If changing into or out of WAL mode the procedure is more complicated.

  Btree *pBt;

  assert( pOp->p1>=0 && pOp->p1<db->nDb );
  assert( (p->btreeMask & (((yDbMask)1)<<pOp->p1))!=0 );
  assert( p->readOnly==0 );
  pBt = db->aDb[pOp->p1].pBt;
  rc = sqlite3BtreeIncrVacuum(pBt);
  VdbeBranchTaken(rc==SQLITE_DONE,2);
  if( rc==SQLITE_DONE ){
    pc = pOp->p2 - 1;
    rc = SQLITE_OK;
  }
  break;
}
#endif

  /* Invoke the xFilter method */
  {
    res = 0;
    apArg = p->apArg;
    for(i = 0; i<nArg; i++){
      apArg[i] = &pArgc[i+1];

    }

    p->inVtabMethod = 1;
    rc = pModule->xFilter(pVtabCursor, iQuery, pOp->p4.z, nArg, apArg);
    p->inVtabMethod = 0;
    sqlite3VtabImportErrmsg(p, pVtab);
    if( rc==SQLITE_OK ){
      res = pModule->xEof(pVtabCursor);
    }
    VdbeBranchTaken(res!=0,2);
    if( res ){
      pc = pOp->p2 - 1;
    }
  }
  pCur->nullRow = 0;

  break;

  p->inVtabMethod = 1;
  rc = pModule->xNext(pCur->pVtabCursor);
  p->inVtabMethod = 0;
  sqlite3VtabImportErrmsg(p, pVtab);
  if( rc==SQLITE_OK ){
    res = pModule->xEof(pCur->pVtabCursor);
  }
  VdbeBranchTaken(!res,2);
  if( !res ){
    /* If there is data, jump to P2 */
    pc = pOp->p2 - 1;
  }
  goto check_for_interrupt;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */

    p->expired = 0;
  }
  break;
}
#endif

#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VUpdate P1 P2 P3 P4 P5
** Synopsis: data=r[P3@P2]
**
** P4 is a pointer to a virtual table object, an sqlite3_vtab structure.
** This opcode invokes the corresponding xUpdate method. P2 values
** are contiguous memory cells starting at P3 to pass to the xUpdate 
** invocation. The value in register (P3+P2-1) corresponds to the 
** p2th element of the argv array passed to xUpdate.

**
** If P2==1 then no insert is performed.  argv[0] is the rowid of
** a row to delete.
**
** P1 is a boolean flag. If it is set to true and the xUpdate call
** is successful, then the value returned by sqlite3_last_insert_rowid() 
** is set to the value of the rowid for the row just inserted.
**
** P5 is the error actions (OE_Replace, OE_Fail, OE_Ignore, etc) to
** apply in the case of a constraint failure on an insert or update.
*/
case OP_VUpdate: {
  sqlite3_vtab *pVtab;
  sqlite3_module *pModule;
  int nArg;
  int i;
  sqlite_int64 rowid;

  if( ALWAYS(pModule->xUpdate) ){
    u8 vtabOnConflict = db->vtabOnConflict;
    apArg = p->apArg;
    pX = &aMem[pOp->p3];
    for(i=0; i<nArg; i++){
      assert( memIsValid(pX) );
      memAboutToChange(p, pX);

      apArg[i] = pX;
      pX++;
    }
    db->vtabOnConflict = pOp->p5;
    rc = pModule->xUpdate(pVtab, nArg, apArg, &rowid);
    db->vtabOnConflict = vtabOnConflict;
    sqlite3VtabImportErrmsg(p, pVtab);

  }
  pOut->u.i = sqlite3BtreeMaxPageCount(pBt, newMax);
  break;
}
#endif



/* Opcode: Init * P2 * P4 *
** Synopsis:  Start at P2
**
** Programs contain a single instance of this opcode as the very first
** opcode.
**
** If tracing is enabled (by the sqlite3_trace()) interface, then
** the UTF-8 string contained in P4 is emitted on the trace callback.
** Or if P4 is blank, use the string returned by sqlite3_sql().
**
** If P2 is not zero, jump to instruction P2.
*/
case OP_Init: {          /* jump */
  char *zTrace;
  char *z;

  if( pOp->p2 ){
    pc = pOp->p2 - 1;
  }
#ifndef SQLITE_OMIT_TRACE
  if( db->xTrace
   && !p->doingRerun
   && (zTrace = (pOp->p4.z ? pOp->p4.z : p->zSql))!=0
  ){
    z = sqlite3VdbeExpandSql(p, zTrace);
    db->xTrace(db->pTraceArg, z);
    sqlite3DbFree(db, z);

#ifdef SQLITE_DEBUG
  if( (db->flags & SQLITE_SqlTrace)!=0
   && (zTrace = (pOp->p4.z ? pOp->p4.z : p->zSql))!=0
  ){
    sqlite3DebugPrintf("SQL-trace: %s\n", zTrace);
  }
#endif /* SQLITE_DEBUG */
#endif /* SQLITE_OMIT_TRACE */
  break;
}



/* Opcode: Noop * * * * *
**
** Do nothing.  This instruction is often useful as a jump
** destination.
*/

    }

#ifdef VDBE_PROFILE
    {
      u64 elapsed = sqlite3Hwtime() - start;
      pOp->cycles += elapsed;
      pOp->cnt++;




    }
#endif

    /* The following code adds nothing to the actual functionality
    ** of the program.  It is only here for testing and debugging.
    ** On the other hand, it does burn CPU cycles every time through
    ** the evaluator loop.  So we can leave it out when NDEBUG is defined.

  ** uses it to implement the blob_read(), blob_write() and 
  ** blob_bytes() functions.
  **
  ** The sqlite3_blob_close() function finalizes the vdbe program,
  ** which closes the b-tree cursor and (possibly) commits the 
  ** transaction.
  */
  static const int iLn = __LINE__+4;
  static const VdbeOpList openBlob[] = {
    /* {OP_Transaction, 0, 0, 0},  // 0: Inserted separately */

    {OP_TableLock, 0, 0, 0},       /* 1: Acquire a read or write lock */

    /* One of the following two instructions is replaced by an OP_Noop. */
    {OP_OpenRead, 0, 0, 0},        /* 2: Open cursor 0 for reading */
    {OP_OpenWrite, 0, 0, 0},       /* 3: Open cursor 0 for read/write */

    {OP_Variable, 1, 1, 1},        /* 4: Push the rowid to the stack */
    {OP_NotExists, 0, 10, 1},      /* 5: Seek the cursor */
    {OP_Column, 0, 0, 1},          /* 6  */
    {OP_ResultRow, 1, 0, 0},       /* 7  */
    {OP_Goto, 0, 4, 0},            /* 8  */
    {OP_Close, 0, 0, 0},           /* 9  */
    {OP_Halt, 0, 0, 0},            /* 10 */
  };

  int rc = SQLITE_OK;
  char *zErr = 0;
  Table *pTab;
  Parse *pParse = 0;
  Incrblob *pBlob = 0;

    pBlob->pStmt = (sqlite3_stmt *)sqlite3VdbeCreate(pParse);
    assert( pBlob->pStmt || db->mallocFailed );
    if( pBlob->pStmt ){
      Vdbe *v = (Vdbe *)pBlob->pStmt;
      int iDb = sqlite3SchemaToIndex(db, pTab->pSchema);




      sqlite3VdbeAddOp4Int(v, OP_Transaction, iDb, flags, 


                           pTab->pSchema->schema_cookie,

                           pTab->pSchema->iGeneration);
      sqlite3VdbeChangeP5(v, 1);     
      sqlite3VdbeAddOpList(v, ArraySize(openBlob), openBlob, iLn);


      /* Make sure a mutex is held on the table to be accessed */
      sqlite3VdbeUsesBtree(v, iDb); 

      /* Configure the OP_TableLock instruction */
#ifdef SQLITE_OMIT_SHARED_CACHE
      sqlite3VdbeChangeToNoop(v, 1);
#else
      sqlite3VdbeChangeP1(v, 1, iDb);
      sqlite3VdbeChangeP2(v, 1, pTab->tnum);
      sqlite3VdbeChangeP3(v, 1, flags);
      sqlite3VdbeChangeP4(v, 1, pTab->zName, P4_TRANSIENT);
#endif

      /* Remove either the OP_OpenWrite or OpenRead. Set the P2 
      ** parameter of the other to pTab->tnum.  */
      sqlite3VdbeChangeToNoop(v, 3 - flags);
      sqlite3VdbeChangeP2(v, 2 + flags, pTab->tnum);
      sqlite3VdbeChangeP3(v, 2 + flags, iDb);

      /* Configure the number of columns. Configure the cursor to
      ** think that the table has one more column than it really
      ** does. An OP_Column to retrieve this imaginary column will
      ** always return an SQL NULL. This is useful because it means
      ** we can invoke OP_Column to fill in the vdbe cursors type 
      ** and offset cache without causing any IO.
      */
      sqlite3VdbeChangeP4(v, 2+flags, SQLITE_INT_TO_PTR(pTab->nCol+1),P4_INT32);
      sqlite3VdbeChangeP2(v, 6, pTab->nCol);
      if( !db->mallocFailed ){
        pParse->nVar = 1;
        pParse->nMem = 1;
        pParse->nTab = 1;
        sqlite3VdbeMakeReady(v, pParse);
      }
    }

    assert( r2->nField>0 );
    for(i=0; i<r2->nField; i++){
      if( r2->aMem[i].flags & MEM_Null ){
        *pRes = -1;
        return;
      }
    }
    assert( r2->default_rc==0 );
  }

  *pRes = sqlite3VdbeRecordCompare(nKey1, pKey1, r2, 0);
}

/*
** This function is called to compare two iterator keys when merging 
** multiple b-tree segments. Parameter iOut is the index of the aTree[] 
** value to recalculate.
*/

      assert( op==TK_DELETE || op==TK_UPDATE || op==TK_INSERT );
      if( op!=TK_DELETE && sqlite3StrICmp("new",zTab) == 0 ){
        pExpr->iTable = 1;
        pTab = pParse->pTriggerTab;
      }else if( op!=TK_INSERT && sqlite3StrICmp("old",zTab)==0 ){
        pExpr->iTable = 0;
        pTab = pParse->pTriggerTab;
      }else{
        pTab = 0;
      }

      if( pTab ){ 
        int iCol;
        pSchema = pTab->pSchema;
        cntTab++;
        for(iCol=0, pCol=pTab->aCol; iCol<pTab->nCol; iCol++, pCol++){

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

    /*
    ** Perhaps the name is a reference to the ROWID
    */

    if( cnt==0 && cntTab==1 && pMatch && sqlite3IsRowid(zCol)
     && HasRowid(pMatch->pTab) ){
      cnt = 1;
      pExpr->iColumn = -1;     /* IMP: R-44911-55124 */
      pExpr->affinity = SQLITE_AFF_INTEGER;
    }

    /*
    ** If the input is of the form Z (not Y.Z or X.Y.Z) then the name Z

  if( pPrior ) pPrior->pNext = pNew;
  pNew->pNext = 0;
  pNew->pLimit = sqlite3ExprDup(db, p->pLimit, flags);
  pNew->pOffset = sqlite3ExprDup(db, p->pOffset, flags);
  pNew->iLimit = 0;
  pNew->iOffset = 0;
  pNew->selFlags = p->selFlags & ~SF_UsesEphemeral;

  pNew->addrOpenEphm[0] = -1;
  pNew->addrOpenEphm[1] = -1;
  pNew->addrOpenEphm[2] = -1;
  pNew->nSelectRow = p->nSelectRow;
  pNew->pWith = withDup(db, p->pWith);
  return pNew;
}
#else
SQLITE_PRIVATE Select *sqlite3SelectDup(sqlite3 *db, Select *p, int flags){
  assert( p==0 );
  return 0;

    case TK_BLOB:
      return 0;
    default:
      return 1;
  }
}



















/*
** Return TRUE if the given expression is a constant which would be
** unchanged by OP_Affinity with the affinity given in the second
** argument.
**
** This routine is used to determine if the OP_Affinity operation
** can be omitted.  When in doubt return FALSE.  A false negative

    assert( p->pEList!=0 );             /* Because of isCandidateForInOpt(p) */
    assert( p->pEList->a[0].pExpr!=0 ); /* Because of isCandidateForInOpt(p) */
    assert( p->pSrc!=0 );               /* Because of isCandidateForInOpt(p) */
    pTab = p->pSrc->a[0].pTab;
    pExpr = p->pEList->a[0].pExpr;
    iCol = (i16)pExpr->iColumn;
   
    /* Code an OP_Transaction and OP_TableLock for <table>. */
    iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
    sqlite3CodeVerifySchema(pParse, iDb);
    sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);

    /* This function is only called from two places. In both cases the vdbe
    ** has already been allocated. So assume sqlite3GetVdbe() is always
    ** successful here.
    */
    assert(v);
    if( iCol<0 ){


      int iAddr = sqlite3CodeOnce(pParse);
      VdbeCoverage(v);

      sqlite3OpenTable(pParse, iTab, iDb, pTab, OP_OpenRead);
      eType = IN_INDEX_ROWID;

      sqlite3VdbeJumpHere(v, iAddr);
    }else{
      Index *pIdx;                         /* Iterator variable */

      int affinity_ok = sqlite3IndexAffinityOk(pX, pTab->aCol[iCol].affinity);

      for(pIdx=pTab->pIndex; pIdx && eType==0 && affinity_ok; pIdx=pIdx->pNext){
        if( (pIdx->aiColumn[0]==iCol)
         && sqlite3FindCollSeq(db, ENC(db), pIdx->azColl[0], 0)==pReq
         && (!mustBeUnique || (pIdx->nKeyCol==1 && pIdx->onError!=OE_None))
        ){
          int iAddr = sqlite3CodeOnce(pParse); VdbeCoverage(v);
          sqlite3VdbeAddOp3(v, OP_OpenRead, iTab, pIdx->tnum, iDb);
          sqlite3VdbeSetP4KeyInfo(pParse, pIdx);
          VdbeComment((v, "%s", pIdx->zName));
          assert( IN_INDEX_INDEX_DESC == IN_INDEX_INDEX_ASC+1 );
          eType = IN_INDEX_INDEX_ASC + pIdx->aSortOrder[0];


          if( prNotFound && !pTab->aCol[iCol].notNull ){
            *prNotFound = ++pParse->nMem;
            sqlite3VdbeAddOp2(v, OP_Null, 0, *prNotFound);
          }
          sqlite3VdbeJumpHere(v, iAddr);
        }
      }
    }
  }

  if( eType==0 ){
    /* Could not found an existing table or index to use as the RHS b-tree.

  **    *  The right-hand side is an expression list containing variables
  **    *  We are inside a trigger
  **
  ** If all of the above are false, then we can run this code just once
  ** save the results, and reuse the same result on subsequent invocations.
  */
  if( !ExprHasProperty(pExpr, EP_VarSelect) ){
    testAddr = sqlite3CodeOnce(pParse); VdbeCoverage(v);
  }

#ifndef SQLITE_OMIT_EXPLAIN
  if( pParse->explain==2 ){
    char *zMsg = sqlite3MPrintf(
        pParse->db, "EXECUTE %s%s SUBQUERY %d", testAddr>=0?"":"CORRELATED ",
        pExpr->op==TK_IN?"LIST":"SCALAR", pParse->iNextSelectId

      ** SELECT... statement are columns, then numeric affinity is used
      ** if either column has NUMERIC or INTEGER affinity. If neither
      ** 'x' nor the SELECT... statement are columns, then numeric affinity
      ** is used.
      */
      pExpr->iTable = pParse->nTab++;
      addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pExpr->iTable, !isRowid);

      pKeyInfo = isRowid ? 0 : sqlite3KeyInfoAlloc(pParse->db, 1, 1);

      if( ExprHasProperty(pExpr, EP_xIsSelect) ){
        /* Case 1:     expr IN (SELECT ...)
        **
        ** Generate code to write the results of the select into the temporary
        ** table allocated and opened above.

          if( isRowid && sqlite3ExprIsInteger(pE2, &iValToIns) ){
            sqlite3VdbeAddOp3(v, OP_InsertInt, pExpr->iTable, r2, iValToIns);
          }else{
            r3 = sqlite3ExprCodeTarget(pParse, pE2, r1);
            if( isRowid ){
              sqlite3VdbeAddOp2(v, OP_MustBeInt, r3,
                                sqlite3VdbeCurrentAddr(v)+2);
              VdbeCoverage(v);
              sqlite3VdbeAddOp3(v, OP_Insert, pExpr->iTable, r2, r3);
            }else{
              sqlite3VdbeAddOp4(v, OP_MakeRecord, r3, 1, r2, &affinity, 1);
              sqlite3ExprCacheAffinityChange(pParse, r3, 1);
              sqlite3VdbeAddOp2(v, OP_IdxInsert, pExpr->iTable, r2);
            }
          }

  /* If the LHS is NULL, then the result is either false or NULL depending
  ** on whether the RHS is empty or not, respectively.
  */
  if( destIfNull==destIfFalse ){
    /* Shortcut for the common case where the false and NULL outcomes are
    ** the same. */
    sqlite3VdbeAddOp2(v, OP_IsNull, r1, destIfNull); VdbeCoverage(v);
  }else{
    int addr1 = sqlite3VdbeAddOp1(v, OP_NotNull, r1); VdbeCoverage(v);
    sqlite3VdbeAddOp2(v, OP_Rewind, pExpr->iTable, destIfFalse);
    VdbeCoverage(v);
    sqlite3VdbeAddOp2(v, OP_Goto, 0, destIfNull);
    sqlite3VdbeJumpHere(v, addr1);
  }

  if( eType==IN_INDEX_ROWID ){
    /* In this case, the RHS is the ROWID of table b-tree
    */
    sqlite3VdbeAddOp2(v, OP_MustBeInt, r1, destIfFalse); VdbeCoverage(v);
    sqlite3VdbeAddOp3(v, OP_NotExists, pExpr->iTable, destIfFalse, r1);
    VdbeCoverage(v);
  }else{
    /* In this case, the RHS is an index b-tree.
    */
    sqlite3VdbeAddOp4(v, OP_Affinity, r1, 1, 0, &affinity, 1);

    /* If the set membership test fails, then the result of the 
    ** "x IN (...)" expression must be either 0 or NULL. If the set
    ** contains no NULL values, then the result is 0. If the set 
    ** contains one or more NULL values, then the result of the
    ** expression is also NULL.
    */
    if( rRhsHasNull==0 || destIfFalse==destIfNull ){
      /* This branch runs if it is known at compile time that the RHS
      ** cannot contain NULL values. This happens as the result
      ** of a "NOT NULL" constraint in the database schema.
      **
      ** Also run this branch if NULL is equivalent to FALSE
      ** for this particular IN operator.
      */
      sqlite3VdbeAddOp4Int(v, OP_NotFound, pExpr->iTable, destIfFalse, r1, 1);
      VdbeCoverage(v);
    }else{
      /* In this branch, the RHS of the IN might contain a NULL and
      ** the presence of a NULL on the RHS makes a difference in the
      ** outcome.
      */
      int j1, j2;

      /* First check to see if the LHS is contained in the RHS.  If so,
      ** then the presence of NULLs in the RHS does not matter, so jump
      ** over all of the code that follows.
      */
      j1 = sqlite3VdbeAddOp4Int(v, OP_Found, pExpr->iTable, 0, r1, 1);
      VdbeCoverage(v);

      /* Here we begin generating code that runs if the LHS is not
      ** contained within the RHS.  Generate additional code that
      ** tests the RHS for NULLs.  If the RHS contains a NULL then
      ** jump to destIfNull.  If there are no NULLs in the RHS then
      ** jump to destIfFalse.
      */
      sqlite3VdbeAddOp2(v, OP_If, rRhsHasNull, destIfNull); VdbeCoverage(v);
      sqlite3VdbeAddOp2(v, OP_IfNot, rRhsHasNull, destIfFalse); VdbeCoverage(v);
      j2 = sqlite3VdbeAddOp4Int(v, OP_Found, pExpr->iTable, 0, rRhsHasNull, 1);
      VdbeCoverage(v);
      sqlite3VdbeAddOp2(v, OP_Integer, 0, rRhsHasNull);

      sqlite3VdbeAddOp2(v, OP_Goto, 0, destIfFalse);
      sqlite3VdbeJumpHere(v, j2);




      sqlite3VdbeAddOp2(v, OP_Integer, 1, rRhsHasNull);
      sqlite3VdbeAddOp2(v, OP_Goto, 0, destIfNull);

      /* The OP_Found at the top of this branch jumps here when true, 
      ** causing the overall IN expression evaluation to fall through.
      */
      sqlite3VdbeJumpHere(v, j1);
    }
  }

#endif /* SQLITE_OMIT_CAST */
    case TK_LT:
    case TK_LE:
    case TK_GT:
    case TK_GE:
    case TK_NE:
    case TK_EQ: {












      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
      r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, &regFree2);
      codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
                  r1, r2, inReg, SQLITE_STOREP2);
      assert(TK_LT==OP_Lt); testcase(op==OP_Lt); VdbeCoverageIf(v,op==OP_Lt);
      assert(TK_LE==OP_Le); testcase(op==OP_Le); VdbeCoverageIf(v,op==OP_Le);
      assert(TK_GT==OP_Gt); testcase(op==OP_Gt); VdbeCoverageIf(v,op==OP_Gt);
      assert(TK_GE==OP_Ge); testcase(op==OP_Ge); VdbeCoverageIf(v,op==OP_Ge);
      assert(TK_EQ==OP_Eq); testcase(op==OP_Eq); VdbeCoverageIf(v,op==OP_Eq);
      assert(TK_NE==OP_Ne); testcase(op==OP_Ne); VdbeCoverageIf(v,op==OP_Ne);
      testcase( regFree1==0 );
      testcase( regFree2==0 );
      break;
    }
    case TK_IS:
    case TK_ISNOT: {
      testcase( op==TK_IS );
      testcase( op==TK_ISNOT );
      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
      r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, &regFree2);
      op = (op==TK_IS) ? TK_EQ : TK_NE;
      codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
                  r1, r2, inReg, SQLITE_STOREP2 | SQLITE_NULLEQ);
      VdbeCoverageIf(v, op==TK_EQ);
      VdbeCoverageIf(v, op==TK_NE);
      testcase( regFree1==0 );
      testcase( regFree2==0 );
      break;
    }
    case TK_AND:
    case TK_OR:
    case TK_PLUS:
    case TK_STAR:
    case TK_MINUS:
    case TK_REM:
    case TK_BITAND:
    case TK_BITOR:
    case TK_SLASH:
    case TK_LSHIFT:
    case TK_RSHIFT: 
    case TK_CONCAT: {
      assert( TK_AND==OP_And );            testcase( op==TK_AND );
      assert( TK_OR==OP_Or );              testcase( op==TK_OR );
      assert( TK_PLUS==OP_Add );           testcase( op==TK_PLUS );
      assert( TK_MINUS==OP_Subtract );     testcase( op==TK_MINUS );
      assert( TK_REM==OP_Remainder );      testcase( op==TK_REM );
      assert( TK_BITAND==OP_BitAnd );      testcase( op==TK_BITAND );
      assert( TK_BITOR==OP_BitOr );        testcase( op==TK_BITOR );
      assert( TK_SLASH==OP_Divide );       testcase( op==TK_SLASH );
      assert( TK_LSHIFT==OP_ShiftLeft );   testcase( op==TK_LSHIFT );
      assert( TK_RSHIFT==OP_ShiftRight );  testcase( op==TK_RSHIFT );
      assert( TK_CONCAT==OP_Concat );      testcase( op==TK_CONCAT );











      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
      r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, &regFree2);
      sqlite3VdbeAddOp3(v, op, r2, r1, target);
      testcase( regFree1==0 );
      testcase( regFree2==0 );
      break;
    }

        testcase( regFree2==0 );
      }
      inReg = target;
      break;
    }
    case TK_BITNOT:
    case TK_NOT: {
      assert( TK_BITNOT==OP_BitNot );   testcase( op==TK_BITNOT );
      assert( TK_NOT==OP_Not );         testcase( op==TK_NOT );


      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
      testcase( regFree1==0 );
      inReg = target;
      sqlite3VdbeAddOp2(v, op, r1, inReg);
      break;
    }
    case TK_ISNULL:
    case TK_NOTNULL: {
      int addr;
      assert( TK_ISNULL==OP_IsNull );   testcase( op==TK_ISNULL );
      assert( TK_NOTNULL==OP_NotNull ); testcase( op==TK_NOTNULL );


      sqlite3VdbeAddOp2(v, OP_Integer, 1, target);
      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
      testcase( regFree1==0 );
      addr = sqlite3VdbeAddOp1(v, op, r1);
      VdbeCoverageIf(v, op==TK_ISNULL);
      VdbeCoverageIf(v, op==TK_NOTNULL);
      sqlite3VdbeAddOp2(v, OP_AddImm, target, -1);
      sqlite3VdbeJumpHere(v, addr);
      break;
    }
    case TK_AGG_FUNCTION: {
      AggInfo *pInfo = pExpr->pAggInfo;
      if( pInfo==0 ){

      */
      if( pDef->funcFlags & SQLITE_FUNC_COALESCE ){
        int endCoalesce = sqlite3VdbeMakeLabel(v);
        assert( nFarg>=2 );
        sqlite3ExprCode(pParse, pFarg->a[0].pExpr, target);
        for(i=1; i<nFarg; i++){
          sqlite3VdbeAddOp2(v, OP_NotNull, target, endCoalesce);
          VdbeCoverage(v);
          sqlite3ExprCacheRemove(pParse, target, 1);
          sqlite3ExprCachePush(pParse);
          sqlite3ExprCode(pParse, pFarg->a[i].pExpr, target);
          sqlite3ExprCachePop(pParse, 1);
        }
        sqlite3VdbeResolveLabel(v, endCoalesce);
        break;

      r1 = sqlite3ExprCodeTemp(pParse, pLeft, &regFree1);
      r2 = sqlite3ExprCodeTemp(pParse, pRight, &regFree2);
      testcase( regFree1==0 );
      testcase( regFree2==0 );
      r3 = sqlite3GetTempReg(pParse);
      r4 = sqlite3GetTempReg(pParse);
      codeCompare(pParse, pLeft, pRight, OP_Ge,
                  r1, r2, r3, SQLITE_STOREP2);  VdbeCoverage(v);
      pLItem++;
      pRight = pLItem->pExpr;
      sqlite3ReleaseTempReg(pParse, regFree2);
      r2 = sqlite3ExprCodeTemp(pParse, pRight, &regFree2);
      testcase( regFree2==0 );
      codeCompare(pParse, pLeft, pRight, OP_Le, r1, r2, r4, SQLITE_STOREP2);
      VdbeCoverage(v);
      sqlite3VdbeAddOp3(v, OP_And, r3, r4, target);
      sqlite3ReleaseTempReg(pParse, r3);
      sqlite3ReleaseTempReg(pParse, r4);
      break;
    }
    case TK_COLLATE: 
    case TK_UPLUS: {

      if( pExpr->affinity==OE_Abort ){
        sqlite3MayAbort(pParse);
      }
      assert( !ExprHasProperty(pExpr, EP_IntValue) );
      if( pExpr->affinity==OE_Ignore ){
        sqlite3VdbeAddOp4(
            v, OP_Halt, SQLITE_OK, OE_Ignore, 0, pExpr->u.zToken,0);
        VdbeCoverage(v);
      }else{
        sqlite3HaltConstraint(pParse, SQLITE_CONSTRAINT_TRIGGER,
                              pExpr->affinity, pExpr->u.zToken, 0, 0);
      }

      break;
    }

}

/*
** Generate code that will evaluate expression pExpr and store the
** results in register target.  The results are guaranteed to appear
** in register target.
*/
SQLITE_PRIVATE void sqlite3ExprCode(Parse *pParse, Expr *pExpr, int target){
  int inReg;

  assert( target>0 && target<=pParse->nMem );
  if( pExpr && pExpr->op==TK_REGISTER ){
    sqlite3VdbeAddOp2(pParse->pVdbe, OP_Copy, pExpr->iTable, target);
  }else{
    inReg = sqlite3ExprCodeTarget(pParse, pExpr, target);
    assert( pParse->pVdbe || pParse->db->mallocFailed );
    if( inReg!=target && pParse->pVdbe ){
      sqlite3VdbeAddOp2(pParse->pVdbe, OP_SCopy, inReg, target);
    }
  }
}

/*
** Generate code that will evaluate expression pExpr and store the
** results in register target.  The results are guaranteed to appear
** in register target.  If the expression is constant, then this routine
** might choose to code the expression at initialization time.
*/
SQLITE_PRIVATE void sqlite3ExprCodeFactorable(Parse *pParse, Expr *pExpr, int target){
  if( pParse->okConstFactor && sqlite3ExprIsConstant(pExpr) ){
    sqlite3ExprCodeAtInit(pParse, pExpr, target, 0);
  }else{
    sqlite3ExprCode(pParse, pExpr, target);
  }
}

/*
** Generate code that evalutes the given expression and puts the result
** in register target.
**
** Also make a copy of the expression results into another "cache" register
** and modify the expression so that the next time it is evaluated,
** the result is a copy of the cache register.
**
** This routine is used for expressions that are used multiple 
** times.  They are evaluated once and the results of the expression
** are reused.
*/
SQLITE_PRIVATE void sqlite3ExprCodeAndCache(Parse *pParse, Expr *pExpr, int target){
  Vdbe *v = pParse->pVdbe;
  int iMem;

  assert( target>0 );







  assert( pExpr->op!=TK_REGISTER );

  sqlite3ExprCode(pParse, pExpr, target);
  iMem = ++pParse->nMem;
  sqlite3VdbeAddOp2(v, OP_Copy, target, iMem);
  exprToRegister(pExpr, iMem);


}

#if defined(SQLITE_ENABLE_TREE_EXPLAIN)
/*
** Generate a human-readable explanation of an expression tree.
*/
SQLITE_PRIVATE void sqlite3ExplainExpr(Vdbe *pOut, Expr *pExpr){

    }
    case TK_LT:
    case TK_LE:
    case TK_GT:
    case TK_GE:
    case TK_NE:
    case TK_EQ: {












      testcase( jumpIfNull==0 );
      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
      r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, &regFree2);
      codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
                  r1, r2, dest, jumpIfNull);
      assert(TK_LT==OP_Lt); testcase(op==OP_Lt); VdbeCoverageIf(v,op==OP_Lt);
      assert(TK_LE==OP_Le); testcase(op==OP_Le); VdbeCoverageIf(v,op==OP_Le);
      assert(TK_GT==OP_Gt); testcase(op==OP_Gt); VdbeCoverageIf(v,op==OP_Gt);
      assert(TK_GE==OP_Ge); testcase(op==OP_Ge); VdbeCoverageIf(v,op==OP_Ge);
      assert(TK_EQ==OP_Eq); testcase(op==OP_Eq); VdbeCoverageIf(v,op==OP_Eq);
      assert(TK_NE==OP_Ne); testcase(op==OP_Ne); VdbeCoverageIf(v,op==OP_Ne);
      testcase( regFree1==0 );
      testcase( regFree2==0 );
      break;
    }
    case TK_IS:
    case TK_ISNOT: {
      testcase( op==TK_IS );
      testcase( op==TK_ISNOT );
      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
      r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, &regFree2);
      op = (op==TK_IS) ? TK_EQ : TK_NE;
      codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
                  r1, r2, dest, SQLITE_NULLEQ);
      VdbeCoverageIf(v, op==TK_EQ);
      VdbeCoverageIf(v, op==TK_NE);
      testcase( regFree1==0 );
      testcase( regFree2==0 );
      break;
    }
    case TK_ISNULL:
    case TK_NOTNULL: {
      assert( TK_ISNULL==OP_IsNull );   testcase( op==TK_ISNULL );
      assert( TK_NOTNULL==OP_NotNull ); testcase( op==TK_NOTNULL );


      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
      sqlite3VdbeAddOp2(v, op, r1, dest);
      VdbeCoverageIf(v, op==TK_ISNULL);
      VdbeCoverageIf(v, op==TK_NOTNULL);
      testcase( regFree1==0 );
      break;
    }
    case TK_BETWEEN: {
      testcase( jumpIfNull==0 );
      exprCodeBetween(pParse, pExpr, dest, 1, jumpIfNull);
      break;

      if( exprAlwaysTrue(pExpr) ){
        sqlite3VdbeAddOp2(v, OP_Goto, 0, dest);
      }else if( exprAlwaysFalse(pExpr) ){
        /* No-op */
      }else{
        r1 = sqlite3ExprCodeTemp(pParse, pExpr, &regFree1);
        sqlite3VdbeAddOp3(v, OP_If, r1, dest, jumpIfNull!=0);
        VdbeCoverage(v);
        testcase( regFree1==0 );
        testcase( jumpIfNull==0 );
      }
      break;
    }
  }
  sqlite3ReleaseTempReg(pParse, regFree1);

    }
    case TK_LT:
    case TK_LE:
    case TK_GT:
    case TK_GE:
    case TK_NE:
    case TK_EQ: {






      testcase( jumpIfNull==0 );
      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
      r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, &regFree2);
      codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
                  r1, r2, dest, jumpIfNull);
      assert(TK_LT==OP_Lt); testcase(op==OP_Lt); VdbeCoverageIf(v,op==OP_Lt);
      assert(TK_LE==OP_Le); testcase(op==OP_Le); VdbeCoverageIf(v,op==OP_Le);
      assert(TK_GT==OP_Gt); testcase(op==OP_Gt); VdbeCoverageIf(v,op==OP_Gt);
      assert(TK_GE==OP_Ge); testcase(op==OP_Ge); VdbeCoverageIf(v,op==OP_Ge);
      assert(TK_EQ==OP_Eq); testcase(op==OP_Eq); VdbeCoverageIf(v,op==OP_Eq);
      assert(TK_NE==OP_Ne); testcase(op==OP_Ne); VdbeCoverageIf(v,op==OP_Ne);
      testcase( regFree1==0 );
      testcase( regFree2==0 );
      break;
    }
    case TK_IS:
    case TK_ISNOT: {
      testcase( pExpr->op==TK_IS );
      testcase( pExpr->op==TK_ISNOT );
      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
      r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, &regFree2);
      op = (pExpr->op==TK_IS) ? TK_NE : TK_EQ;
      codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
                  r1, r2, dest, SQLITE_NULLEQ);
      VdbeCoverageIf(v, op==TK_EQ);
      VdbeCoverageIf(v, op==TK_NE);
      testcase( regFree1==0 );
      testcase( regFree2==0 );
      break;
    }
    case TK_ISNULL:
    case TK_NOTNULL: {


      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
      sqlite3VdbeAddOp2(v, op, r1, dest);
      testcase( op==TK_ISNULL );   VdbeCoverageIf(v, op==TK_ISNULL);
      testcase( op==TK_NOTNULL );  VdbeCoverageIf(v, op==TK_NOTNULL);
      testcase( regFree1==0 );
      break;
    }
    case TK_BETWEEN: {
      testcase( jumpIfNull==0 );
      exprCodeBetween(pParse, pExpr, dest, 0, jumpIfNull);
      break;

      if( exprAlwaysFalse(pExpr) ){
        sqlite3VdbeAddOp2(v, OP_Goto, 0, dest);
      }else if( exprAlwaysTrue(pExpr) ){
        /* no-op */
      }else{
        r1 = sqlite3ExprCodeTemp(pParse, pExpr, &regFree1);
        sqlite3VdbeAddOp3(v, OP_IfNot, r1, dest, jumpIfNull!=0);
        VdbeCoverage(v);
        testcase( regFree1==0 );
        testcase( jumpIfNull==0 );
      }
      break;
    }
  }
  sqlite3ReleaseTempReg(pParse, regFree1);

      do {
        zCsr += len;
        len = sqlite3GetToken(zCsr, &token);
      } while( token==TK_SPACE );
      assert( len>0 );
    } while( token!=TK_LP && token!=TK_USING );

    zRet = sqlite3MPrintf(db, "%.*s\"%w\"%s", (int)(((u8*)tname.z) - zSql),
       zSql, zTableName, tname.z+tname.n);
    sqlite3_result_text(context, zRet, -1, SQLITE_DYNAMIC);
  }
}

/*
** This C function implements an SQL user function that is used by SQL code
** generated by the ALTER TABLE ... RENAME command to modify the definition

      }while( token==TK_SPACE );

      zParent = sqlite3DbStrNDup(db, (const char *)z, n);
      if( zParent==0 ) break;
      sqlite3Dequote(zParent);
      if( 0==sqlite3StrICmp((const char *)zOld, zParent) ){
        char *zOut = sqlite3MPrintf(db, "%s%.*s\"%w\"", 
            (zOutput?zOutput:""), (int)(z-zInput), zInput, (const char *)zNew
        );
        sqlite3DbFree(db, zOutput);
        zOutput = zOut;
        zInput = &z[n];
      }
      sqlite3DbFree(db, zParent);
    }

        dist = 0;
      }
    } while( dist!=2 || (token!=TK_WHEN && token!=TK_FOR && token!=TK_BEGIN) );

    /* Variable tname now contains the token that is the old table-name
    ** in the CREATE TRIGGER statement.
    */
    zRet = sqlite3MPrintf(db, "%.*s\"%w\"%s", (int)(((u8*)tname.z) - zSql),
       zSql, zTableName, tname.z+tname.n);
    sqlite3_result_text(context, zRet, -1, SQLITE_DYNAMIC);
  }
}
#endif   /* !SQLITE_OMIT_TRIGGER */

/*
** Register built-in functions used to help implement ALTER TABLE

    pVTab = sqlite3GetVTable(db, pTab);
    if( pVTab->pVtab->pModule->xRename==0 ){
      pVTab = 0;
    }
  }
#endif

  /* Begin a transaction for database iDb. 
  ** Then modify the schema cookie (since the ALTER TABLE modifies the
  ** schema). Open a statement transaction if the table is a virtual
  ** table.
  */
  v = sqlite3GetVdbe(pParse);
  if( v==0 ){
    goto exit_rename_table;

    int r1 = sqlite3GetTempReg(pParse);
    int r2 = sqlite3GetTempReg(pParse);
    int j1;
    sqlite3VdbeAddOp3(v, OP_ReadCookie, iDb, r1, BTREE_FILE_FORMAT);
    sqlite3VdbeUsesBtree(v, iDb);
    sqlite3VdbeAddOp2(v, OP_Integer, minFormat, r2);
    j1 = sqlite3VdbeAddOp3(v, OP_Ge, r2, 0, r1);
    sqlite3VdbeChangeP5(v, SQLITE_NOTNULL); VdbeCoverage(v);
    sqlite3VdbeAddOp3(v, OP_SetCookie, iDb, BTREE_FILE_FORMAT, r2);
    sqlite3VdbeJumpHere(v, j1);
    sqlite3ReleaseTempReg(pParse, r1);
    sqlite3ReleaseTempReg(pParse, r2);
  }
}

    **   Rewind csr
    **   if eof(csr) goto end_of_scan;
    **   regChng = 0
    **   goto next_push_0;
    **
    */
    addrRewind = sqlite3VdbeAddOp1(v, OP_Rewind, iIdxCur);
    VdbeCoverage(v);
    sqlite3VdbeAddOp2(v, OP_Integer, 0, regChng);
    addrGotoChng0 = sqlite3VdbeAddOp0(v, OP_Goto);

    /*
    **  next_row:
    **   regChng = 0
    **   if( idx(0) != regPrev(0) ) goto chng_addr_0

    for(i=0; i<nCol; i++){
      char *pColl = (char*)sqlite3LocateCollSeq(pParse, pIdx->azColl[i]);
      sqlite3VdbeAddOp2(v, OP_Integer, i, regChng);
      sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, i, regTemp);
      aGotoChng[i] = 
      sqlite3VdbeAddOp4(v, OP_Ne, regTemp, 0, regPrev+i, pColl, P4_COLLSEQ);
      sqlite3VdbeChangeP5(v, SQLITE_NULLEQ);
      VdbeCoverage(v);
    }
    sqlite3VdbeAddOp2(v, OP_Integer, nCol, regChng);
    aGotoChng[nCol] = sqlite3VdbeAddOp0(v, OP_Goto);

    /*
    **  chng_addr_0:
    **   regPrev(0) = idx(0)

      sqlite3ReleaseTempRange(pParse, regKey, pPk->nKeyCol);
    }
#endif
    assert( regChng==(regStat4+1) );
    sqlite3VdbeAddOp3(v, OP_Function, 1, regStat4, regTemp);
    sqlite3VdbeChangeP4(v, -1, (char*)&statPushFuncdef, P4_FUNCDEF);
    sqlite3VdbeChangeP5(v, 2+IsStat34);
    sqlite3VdbeAddOp2(v, OP_Next, iIdxCur, addrNextRow); VdbeCoverage(v);

    /* Add the entry to the stat1 table. */
    callStatGet(v, regStat4, STAT_GET_STAT1, regStat1);
    sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 3, regTemp, "aaa", 0);
    sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur, regNewRowid);
    sqlite3VdbeAddOp3(v, OP_Insert, iStatCur, regTemp, regNewRowid);
    sqlite3VdbeChangeP5(v, OPFLAG_APPEND);

      u8 seekOp = HasRowid(pTab) ? OP_NotExists : OP_NotFound;

      pParse->nMem = MAX(pParse->nMem, regCol+nCol+1);

      addrNext = sqlite3VdbeCurrentAddr(v);
      callStatGet(v, regStat4, STAT_GET_ROWID, regSampleRowid);
      addrIsNull = sqlite3VdbeAddOp1(v, OP_IsNull, regSampleRowid);
      VdbeCoverage(v);
      callStatGet(v, regStat4, STAT_GET_NEQ, regEq);
      callStatGet(v, regStat4, STAT_GET_NLT, regLt);
      callStatGet(v, regStat4, STAT_GET_NDLT, regDLt);
      sqlite3VdbeAddOp4Int(v, seekOp, iTabCur, addrNext, regSampleRowid, 0);
      VdbeCoverage(v);
#ifdef SQLITE_ENABLE_STAT3
      sqlite3ExprCodeGetColumnOfTable(v, pTab, iTabCur, 
                                      pIdx->aiColumn[0], regSample);
#else
      for(i=0; i<nCol; i++){
        i16 iCol = pIdx->aiColumn[i];
        sqlite3ExprCodeGetColumnOfTable(v, pTab, iTabCur, iCol, regCol+i);
      }
      sqlite3VdbeAddOp3(v, OP_MakeRecord, regCol, nCol+1, regSample);
#endif
      sqlite3VdbeAddOp3(v, OP_MakeRecord, regTabname, 6, regTemp);
      sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur+1, regNewRowid);
      sqlite3VdbeAddOp3(v, OP_Insert, iStatCur+1, regTemp, regNewRowid);
      sqlite3VdbeAddOp2(v, OP_Goto, 0, addrNext);
      sqlite3VdbeJumpHere(v, addrIsNull);
    }
#endif /* SQLITE_ENABLE_STAT3_OR_STAT4 */

    /* End of analysis */
    sqlite3VdbeJumpHere(v, addrRewind);
    sqlite3DbFree(db, aGotoChng);
  }


  /* Create a single sqlite_stat1 entry containing NULL as the index
  ** name and the row count as the content.
  */
  if( pOnlyIdx==0 && needTableCnt ){
    VdbeComment((v, "%s", pTab->zName));
    sqlite3VdbeAddOp2(v, OP_Count, iTabCur, regStat1);
    jZeroRows = sqlite3VdbeAddOp1(v, OP_IfNot, regStat1); VdbeCoverage(v);
    sqlite3VdbeAddOp2(v, OP_Null, 0, regIdxname);
    sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 3, regTemp, "aaa", 0);
    sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur, regNewRowid);
    sqlite3VdbeAddOp3(v, OP_Insert, iStatCur, regTemp, regNewRowid);
    sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
    sqlite3VdbeJumpHere(v, jZeroRows);
  }