**     CREATE INDEX
**     DROP INDEX
**     creating ID lists
**     BEGIN TRANSACTION
**     COMMIT
**     ROLLBACK
**
** $Id: build.c,v 1.481 2008/04/17 20:59:38 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** This routine is called when a new SQL statement is beginning to
** be parsed.  Initialize the pParse structure as needed.
................................................................................
  if( pIndex->onError!=OE_None ){
    int j1, j2;
    int regRowid;

    regRowid = regIdxKey + pIndex->nColumn;
    j1 = sqlite3VdbeAddOp3(v, OP_IsNull, regIdxKey, 0, pIndex->nColumn);
    j2 = sqlite3VdbeAddOp4(v, OP_IsUnique, iIdx,
                           0, regRowid, (char*)(sqlite3_intptr_t)regRecord, P4_INT32);
    sqlite3VdbeAddOp4(v, OP_Halt, SQLITE_CONSTRAINT, OE_Abort, 0,
                    "indexed columns are not unique", P4_STATIC);
    sqlite3VdbeJumpHere(v, j1);
    sqlite3VdbeJumpHere(v, j2);
  }
  sqlite3VdbeAddOp2(v, OP_IdxInsert, iIdx, regRecord);
  sqlite3ReleaseTempReg(pParse, regRecord);

**     CREATE INDEX
**     DROP INDEX
**     creating ID lists
**     BEGIN TRANSACTION
**     COMMIT
**     ROLLBACK
**
** $Id: build.c,v 1.482 2008/04/27 18:40:12 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** This routine is called when a new SQL statement is beginning to
** be parsed.  Initialize the pParse structure as needed.
................................................................................
  if( pIndex->onError!=OE_None ){
    int j1, j2;
    int regRowid;

    regRowid = regIdxKey + pIndex->nColumn;
    j1 = sqlite3VdbeAddOp3(v, OP_IsNull, regIdxKey, 0, pIndex->nColumn);
    j2 = sqlite3VdbeAddOp4(v, OP_IsUnique, iIdx,
                           0, regRowid, (char*)regRecord, P4_INT32);
    sqlite3VdbeAddOp4(v, OP_Halt, SQLITE_CONSTRAINT, OE_Abort, 0,
                    "indexed columns are not unique", P4_STATIC);
    sqlite3VdbeJumpHere(v, j1);
    sqlite3VdbeJumpHere(v, j2);
  }
  sqlite3VdbeAddOp2(v, OP_IdxInsert, iIdx, regRecord);
  sqlite3ReleaseTempReg(pParse, regRecord);

** This file contains the C functions that implement various SQL
** functions of SQLite.  
**
** There is only one exported symbol in this file - the function
** sqliteRegisterBuildinFunctions() found at the bottom of the file.
** All other code has file scope.
**
** $Id: func.c,v 1.191 2008/03/20 16:30:18 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>
#include <stdlib.h>
#include <assert.h>
#include "vdbeInt.h"

................................................................................
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  const unsigned char *zIn;         /* Input string */
  const unsigned char *zCharSet;    /* Set of characters to trim */
  int nIn;                          /* Number of bytes in input */
  sqlite3_intptr_t flags;           /* 1: trimleft  2: trimright  3: trim */
  int i;                            /* Loop counter */
  unsigned char *aLen;              /* Length of each character in zCharSet */
  unsigned char **azChar;           /* Individual characters in zCharSet */
  int nChar;                        /* Number of characters in zCharSet */

  if( sqlite3_value_type(argv[0])==SQLITE_NULL ){
    return;
................................................................................
        azChar[nChar] = (unsigned char *)z;
        SQLITE_SKIP_UTF8(z);
        aLen[nChar] = z - azChar[nChar];
      }
    }
  }
  if( nChar>0 ){
    flags = (sqlite3_intptr_t)sqlite3_user_data(context);
    if( flags & 1 ){
      while( nIn>0 ){
        int len;
        for(i=0; i<nChar; i++){
          len = aLen[i];
          if( memcmp(zIn, azChar[i], len)==0 ) break;
        }
................................................................................
    { "group_concat", 2, 0, 0, groupConcatStep, groupConcatFinalize },
  };
  int i;

  for(i=0; i<sizeof(aFuncs)/sizeof(aFuncs[0]); i++){
    void *pArg;
    u8 argType = aFuncs[i].argType;
    pArg = (void*)(sqlite3_intptr_t)argType;
    sqlite3CreateFunc(db, aFuncs[i].zName, aFuncs[i].nArg,
        aFuncs[i].eTextRep, pArg, aFuncs[i].xFunc, 0, 0);
    if( aFuncs[i].needCollSeq ){
      FuncDef *pFunc = sqlite3FindFunction(db, aFuncs[i].zName, 
          strlen(aFuncs[i].zName), aFuncs[i].nArg, aFuncs[i].eTextRep, 0);
      if( pFunc && aFuncs[i].needCollSeq ){
        pFunc->needCollSeq = 1;
................................................................................
#ifndef SQLITE_OMIT_ALTERTABLE
  sqlite3AlterFunctions(db);
#endif
#ifndef SQLITE_OMIT_PARSER
  sqlite3AttachFunctions(db);
#endif
  for(i=0; i<sizeof(aAggs)/sizeof(aAggs[0]); i++){
    void *pArg = (void*)(sqlite3_intptr_t)aAggs[i].argType;
    sqlite3CreateFunc(db, aAggs[i].zName, aAggs[i].nArg, SQLITE_UTF8, 
        pArg, 0, aAggs[i].xStep, aAggs[i].xFinalize);
    if( aAggs[i].needCollSeq ){
      FuncDef *pFunc = sqlite3FindFunction( db, aAggs[i].zName,
          strlen(aAggs[i].zName), aAggs[i].nArg, SQLITE_UTF8, 0);
      if( pFunc && aAggs[i].needCollSeq ){
        pFunc->needCollSeq = 1;

** This file contains the C functions that implement various SQL
** functions of SQLite.  
**
** There is only one exported symbol in this file - the function
** sqliteRegisterBuildinFunctions() found at the bottom of the file.
** All other code has file scope.
**
** $Id: func.c,v 1.192 2008/04/27 18:40:12 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>
#include <stdlib.h>
#include <assert.h>
#include "vdbeInt.h"

................................................................................
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  const unsigned char *zIn;         /* Input string */
  const unsigned char *zCharSet;    /* Set of characters to trim */
  int nIn;                          /* Number of bytes in input */
  int flags;                        /* 1: trimleft  2: trimright  3: trim */
  int i;                            /* Loop counter */
  unsigned char *aLen;              /* Length of each character in zCharSet */
  unsigned char **azChar;           /* Individual characters in zCharSet */
  int nChar;                        /* Number of characters in zCharSet */

  if( sqlite3_value_type(argv[0])==SQLITE_NULL ){
    return;
................................................................................
        azChar[nChar] = (unsigned char *)z;
        SQLITE_SKIP_UTF8(z);
        aLen[nChar] = z - azChar[nChar];
      }
    }
  }
  if( nChar>0 ){
    flags = (int)sqlite3_user_data(context);
    if( flags & 1 ){
      while( nIn>0 ){
        int len;
        for(i=0; i<nChar; i++){
          len = aLen[i];
          if( memcmp(zIn, azChar[i], len)==0 ) break;
        }
................................................................................
    { "group_concat", 2, 0, 0, groupConcatStep, groupConcatFinalize },
  };
  int i;

  for(i=0; i<sizeof(aFuncs)/sizeof(aFuncs[0]); i++){
    void *pArg;
    u8 argType = aFuncs[i].argType;
    pArg = (void*)(int)argType;
    sqlite3CreateFunc(db, aFuncs[i].zName, aFuncs[i].nArg,
        aFuncs[i].eTextRep, pArg, aFuncs[i].xFunc, 0, 0);
    if( aFuncs[i].needCollSeq ){
      FuncDef *pFunc = sqlite3FindFunction(db, aFuncs[i].zName, 
          strlen(aFuncs[i].zName), aFuncs[i].nArg, aFuncs[i].eTextRep, 0);
      if( pFunc && aFuncs[i].needCollSeq ){
        pFunc->needCollSeq = 1;
................................................................................
#ifndef SQLITE_OMIT_ALTERTABLE
  sqlite3AlterFunctions(db);
#endif
#ifndef SQLITE_OMIT_PARSER
  sqlite3AttachFunctions(db);
#endif
  for(i=0; i<sizeof(aAggs)/sizeof(aAggs[0]); i++){
    void *pArg = (void*)(int)aAggs[i].argType;
    sqlite3CreateFunc(db, aAggs[i].zName, aAggs[i].nArg, SQLITE_UTF8, 
        pArg, 0, aAggs[i].xStep, aAggs[i].xFinalize);
    if( aAggs[i].needCollSeq ){
      FuncDef *pFunc = sqlite3FindFunction( db, aAggs[i].zName,
          strlen(aAggs[i].zName), aAggs[i].nArg, SQLITE_UTF8, 0);
      if( pFunc && aAggs[i].needCollSeq ){
        pFunc->needCollSeq = 1;

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle INSERT statements in SQLite.
**
** $Id: insert.c,v 1.236 2008/04/11 15:36:03 drh Exp $
*/
#include "sqliteInt.h"

/*
** Set P4 of the most recently inserted opcode to a column affinity
** string for index pIdx. A column affinity string has one character
** for each column in the table, according to the affinity of the column:
................................................................................
    

    /* Check to see if the new index entry will be unique */
    j2 = sqlite3VdbeAddOp3(v, OP_IsNull, regIdx, 0, pIdx->nColumn);
    regR = sqlite3GetTempReg(pParse);
    sqlite3VdbeAddOp2(v, OP_SCopy, regRowid-hasTwoRowids, regR);
    j3 = sqlite3VdbeAddOp4(v, OP_IsUnique, baseCur+iCur+1, 0,
                           regR, (char*)(sqlite3_intptr_t)aRegIdx[iCur],
                           P4_INT32);

    /* Generate code that executes if the new index entry is not unique */
    assert( onError==OE_Rollback || onError==OE_Abort || onError==OE_Fail
        || onError==OE_Ignore || onError==OE_Replace );
    switch( onError ){
      case OE_Rollback:

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle INSERT statements in SQLite.
**
** $Id: insert.c,v 1.237 2008/04/27 18:40:12 drh Exp $
*/
#include "sqliteInt.h"

/*
** Set P4 of the most recently inserted opcode to a column affinity
** string for index pIdx. A column affinity string has one character
** for each column in the table, according to the affinity of the column:
................................................................................
    

    /* Check to see if the new index entry will be unique */
    j2 = sqlite3VdbeAddOp3(v, OP_IsNull, regIdx, 0, pIdx->nColumn);
    regR = sqlite3GetTempReg(pParse);
    sqlite3VdbeAddOp2(v, OP_SCopy, regRowid-hasTwoRowids, regR);
    j3 = sqlite3VdbeAddOp4(v, OP_IsUnique, baseCur+iCur+1, 0,
                           regR, (char*)aRegIdx[iCur],
                           P4_INT32);

    /* Generate code that executes if the new index entry is not unique */
    assert( onError==OE_Rollback || onError==OE_Abort || onError==OE_Fail
        || onError==OE_Ignore || onError==OE_Replace );
    switch( onError ){
      case OE_Rollback:

**    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.
**
** @(#) $Id: sqliteInt.h,v 1.695 2008/04/24 19:15:10 shane Exp $
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_

/*
** Include the configuration header output by 'configure' if it was run
** (otherwise we get an empty default).
................................................................................
#pragma warn -csu /* Comparing signed and unsigned */
#pragma warn -spa /* Suspicous pointer arithmetic */
#endif

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

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

/*
** If possible, use the C99 intptr_t type to define an integral type of
** equivalent size to a pointer.  (Technically it's >= sizeof(void *), but
** practically it's == sizeof(void *)).  We fall back to an int if this type
** isn't defined.
*/
#ifdef HAVE_INTPTR_T
  typedef intptr_t sqlite3_intptr_t;
#else
  typedef int sqlite3_intptr_t;
#endif

/*
** A macro used to aid in coverage testing.  When doing coverage
** testing, the condition inside the argument must be evaluated 
** both true and false in order to get full branch coverage.
** This macro can be inserted to ensure adequate test coverage
** in places where simple condition/decision coverage is inadequate.
*/

**    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.
**
** @(#) $Id: sqliteInt.h,v 1.696 2008/04/27 18:40:12 drh Exp $
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_

/*
** Include the configuration header output by 'configure' if it was run
** (otherwise we get an empty default).
................................................................................
#pragma warn -csu /* Comparing signed and unsigned */
#pragma warn -spa /* Suspicous pointer arithmetic */
#endif

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























/*
** A macro used to aid in coverage testing.  When doing coverage
** testing, the condition inside the argument must be evaluated 
** both true and false in order to get full branch coverage.
** This macro can be inserted to ensure adequate test coverage
** in places where simple condition/decision coverage is inadequate.
*/

  if( res.azResult==0 ){
     db->errCode = SQLITE_NOMEM;
     return SQLITE_NOMEM;
  }
  res.azResult[0] = 0;
  rc = sqlite3_exec(db, zSql, sqlite3_get_table_cb, &res, pzErrMsg);
  assert( sizeof(res.azResult[0])>= sizeof(res.nData) );
  res.azResult[0] = (char*)(sqlite3_intptr_t)res.nData;
  if( (rc&0xff)==SQLITE_ABORT ){
    sqlite3_free_table(&res.azResult[1]);
    if( res.zErrMsg ){
      if( pzErrMsg ){
        sqlite3_free(*pzErrMsg);
        *pzErrMsg = sqlite3_mprintf("%s",res.zErrMsg);
      }
................................................................................
/*
** This routine frees the space the sqlite3_get_table() malloced.
*/
void sqlite3_free_table(
  char **azResult            /* Result returned from from sqlite3_get_table() */
){
  if( azResult ){
    sqlite3_intptr_t i, n;
    azResult--;
    assert( azResult!=0 );
    n = (sqlite3_intptr_t)azResult[0];
    for(i=1; i<n; i++){ if( azResult[i] ) sqlite3_free(azResult[i]); }
    sqlite3_free(azResult);
  }
}

#endif /* SQLITE_OMIT_GET_TABLE */

  if( res.azResult==0 ){
     db->errCode = SQLITE_NOMEM;
     return SQLITE_NOMEM;
  }
  res.azResult[0] = 0;
  rc = sqlite3_exec(db, zSql, sqlite3_get_table_cb, &res, pzErrMsg);
  assert( sizeof(res.azResult[0])>= sizeof(res.nData) );
  res.azResult[0] = (char*)res.nData;
  if( (rc&0xff)==SQLITE_ABORT ){
    sqlite3_free_table(&res.azResult[1]);
    if( res.zErrMsg ){
      if( pzErrMsg ){
        sqlite3_free(*pzErrMsg);
        *pzErrMsg = sqlite3_mprintf("%s",res.zErrMsg);
      }
................................................................................
/*
** This routine frees the space the sqlite3_get_table() malloced.
*/
void sqlite3_free_table(
  char **azResult            /* Result returned from from sqlite3_get_table() */
){
  if( azResult ){
    int i, n;
    azResult--;
    assert( azResult!=0 );
    n = (int)azResult[0];
    for(i=1; i<n; i++){ if( azResult[i] ) sqlite3_free(azResult[i]); }
    sqlite3_free(azResult);
  }
}

#endif /* SQLITE_OMIT_GET_TABLE */

**
*************************************************************************
** This file contains code used for creating, destroying, and populating
** a VDBE (or an "sqlite3_stmt" as it is known to the outside world.)  Prior
** to version 2.8.7, all this code was combined into the vdbe.c source file.
** But that file was getting too big so this subroutines were split out.
**
** $Id: vdbeaux.c,v 1.379 2008/04/24 19:15:11 shane Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>
#include "vdbeInt.h"



................................................................................
  }
  pOp = &p->aOp[addr];
  freeP4(pOp->p4type, pOp->p4.p);
  pOp->p4.p = 0;
  if( n==P4_INT32 ){
    /* Note: this cast is safe, because the origin data point was an int
    ** that was cast to a (const char *). */
    pOp->p4.i = (int)(sqlite3_intptr_t)zP4;
    pOp->p4type = n;
  }else if( zP4==0 ){
    pOp->p4.p = 0;
    pOp->p4type = P4_NOTUSED;
  }else if( n==P4_KEYINFO ){
    KeyInfo *pKeyInfo;
    int nField, nByte;

**
*************************************************************************
** This file contains code used for creating, destroying, and populating
** a VDBE (or an "sqlite3_stmt" as it is known to the outside world.)  Prior
** to version 2.8.7, all this code was combined into the vdbe.c source file.
** But that file was getting too big so this subroutines were split out.
**
** $Id: vdbeaux.c,v 1.380 2008/04/27 18:40:12 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>
#include "vdbeInt.h"



................................................................................
  }
  pOp = &p->aOp[addr];
  freeP4(pOp->p4type, pOp->p4.p);
  pOp->p4.p = 0;
  if( n==P4_INT32 ){
    /* Note: this cast is safe, because the origin data point was an int
    ** that was cast to a (const char *). */
    pOp->p4.i = (int)zP4;
    pOp->p4type = n;
  }else if( zP4==0 ){
    pOp->p4.p = 0;
    pOp->p4type = P4_NOTUSED;
  }else if( n==P4_KEYINFO ){
    KeyInfo *pKeyInfo;
    int nField, nByte;

    return 0;
  }
  assert( (MEM_Blob>>3) == MEM_Str );
  pVal->flags |= (pVal->flags & MEM_Blob)>>3;
  expandBlob(pVal);
  if( pVal->flags&MEM_Str ){
    sqlite3VdbeChangeEncoding(pVal, enc & ~SQLITE_UTF16_ALIGNED);
    if( (enc & SQLITE_UTF16_ALIGNED)!=0 && 1==(1&(sqlite3_intptr_t)pVal->z) ){
      assert( (pVal->flags & (MEM_Ephem|MEM_Static))!=0 );
      if( sqlite3VdbeMemMakeWriteable(pVal)!=SQLITE_OK ){
        return 0;
      }
    }
    sqlite3VdbeMemNulTerminate(pVal);
  }else{
    assert( (pVal->flags&MEM_Blob)==0 );
    sqlite3VdbeMemStringify(pVal, enc);
    assert( 0==(1&(sqlite3_intptr_t)pVal->z) );
  }
  assert(pVal->enc==(enc & ~SQLITE_UTF16_ALIGNED) || pVal->db==0
              || pVal->db->mallocFailed );
  if( pVal->enc==(enc & ~SQLITE_UTF16_ALIGNED) ){
    return pVal->z;
  }else{
    return 0;

    return 0;
  }
  assert( (MEM_Blob>>3) == MEM_Str );
  pVal->flags |= (pVal->flags & MEM_Blob)>>3;
  expandBlob(pVal);
  if( pVal->flags&MEM_Str ){
    sqlite3VdbeChangeEncoding(pVal, enc & ~SQLITE_UTF16_ALIGNED);
    if( (enc & SQLITE_UTF16_ALIGNED)!=0 && 1==(1&(int)pVal->z) ){
      assert( (pVal->flags & (MEM_Ephem|MEM_Static))!=0 );
      if( sqlite3VdbeMemMakeWriteable(pVal)!=SQLITE_OK ){
        return 0;
      }
    }
    sqlite3VdbeMemNulTerminate(pVal);
  }else{
    assert( (pVal->flags&MEM_Blob)==0 );
    sqlite3VdbeMemStringify(pVal, enc);
    assert( 0==(1&(int)pVal->z) );
  }
  assert(pVal->enc==(enc & ~SQLITE_UTF16_ALIGNED) || pVal->db==0
              || pVal->db->mallocFailed );
  if( pVal->enc==(enc & ~SQLITE_UTF16_ALIGNED) ){
    return pVal->z;
  }else{
    return 0;

**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains code used to help implement virtual tables.
**
** $Id: vtab.c,v 1.66 2008/04/10 18:35:22 drh Exp $
*/
#ifndef SQLITE_OMIT_VIRTUALTABLE
#include "sqliteInt.h"

static int createModule(
  sqlite3 *db,                    /* Database in which module is registered */
  const char *zName,              /* Name assigned to this module */
................................................................................
** This function invokes either the xRollback or xCommit method
** of each of the virtual tables in the sqlite3.aVTrans array. The method
** called is identified by the second argument, "offset", which is
** the offset of the method to call in the sqlite3_module structure.
**
** The array is cleared after invoking the callbacks. 
*/
static void callFinaliser(sqlite3 *db, sqlite3_intptr_t offset){
  int i;
  if( db->aVTrans ){
    for(i=0; i<db->nVTrans && db->aVTrans[i]; i++){
      sqlite3_vtab *pVtab = db->aVTrans[i];
      int (*x)(sqlite3_vtab *);
      x = *(int (**)(sqlite3_vtab *))((char *)pVtab->pModule + offset);
      if( x ) x(pVtab);
................................................................................
}

/*
** Invoke the xRollback method of all virtual tables in the 
** sqlite3.aVTrans array. Then clear the array itself.
*/
int sqlite3VtabRollback(sqlite3 *db){
  callFinaliser(db, (sqlite3_intptr_t)(&((sqlite3_module *)0)->xRollback));
  return SQLITE_OK;
}

/*
** Invoke the xCommit method of all virtual tables in the 
** sqlite3.aVTrans array. Then clear the array itself.
*/
int sqlite3VtabCommit(sqlite3 *db){
  callFinaliser(db, (sqlite3_intptr_t)(&((sqlite3_module *)0)->xCommit));
  return SQLITE_OK;
}

/*
** If the virtual table pVtab supports the transaction interface
** (xBegin/xRollback/xCommit and optionally xSync) and a transaction is
** not currently open, invoke the xBegin method now.

**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains code used to help implement virtual tables.
**
** $Id: vtab.c,v 1.67 2008/04/27 18:40:12 drh Exp $
*/
#ifndef SQLITE_OMIT_VIRTUALTABLE
#include "sqliteInt.h"

static int createModule(
  sqlite3 *db,                    /* Database in which module is registered */
  const char *zName,              /* Name assigned to this module */
................................................................................
** This function invokes either the xRollback or xCommit method
** of each of the virtual tables in the sqlite3.aVTrans array. The method
** called is identified by the second argument, "offset", which is
** the offset of the method to call in the sqlite3_module structure.
**
** The array is cleared after invoking the callbacks. 
*/
static void callFinaliser(sqlite3 *db, int offset){
  int i;
  if( db->aVTrans ){
    for(i=0; i<db->nVTrans && db->aVTrans[i]; i++){
      sqlite3_vtab *pVtab = db->aVTrans[i];
      int (*x)(sqlite3_vtab *);
      x = *(int (**)(sqlite3_vtab *))((char *)pVtab->pModule + offset);
      if( x ) x(pVtab);
................................................................................
}

/*
** Invoke the xRollback method of all virtual tables in the 
** sqlite3.aVTrans array. Then clear the array itself.
*/
int sqlite3VtabRollback(sqlite3 *db){
  callFinaliser(db, offsetof(sqlite3_module,xRollback));
  return SQLITE_OK;
}

/*
** Invoke the xCommit method of all virtual tables in the 
** sqlite3.aVTrans array. Then clear the array itself.
*/
int sqlite3VtabCommit(sqlite3 *db){
  callFinaliser(db, offsetof(sqlite3_module,xCommit));
  return SQLITE_OK;
}

/*
** If the virtual table pVtab supports the transaction interface
** (xBegin/xRollback/xCommit and optionally xSync) and a transaction is
** not currently open, invoke the xBegin method now.