SQLite

# Scan for "case OP_aaaa:" lines in the vdbe.c file
/^case OP_/ {
  name = $2
  sub(/:/,"",name)
  sub("\r","",name)
  op[name] = -1
  out1[name] = 0
  out2[name] = 0
  out3[name] = 0
  jump[name] = 0
  in1[name] = 0
  in2[name] = 0
  in3[name] = 0
  nopush[name] = 0
  for(i=3; i<NF; i++){
    if($i=="same" && $(i+1)=="as"){
      sym = $(i+2)
      sub(/,/,"",sym)
      op[name] = tk[sym]
      used[op[name]] = 1
      sameas[op[name]] = sym
    }
    x = $i
    sub(",","",x)
    if(x=="no-push"){
      nopush[name] = 1
    }else if(x=="out1"){
      out1[name] = 1
    }else if(x=="out2"){
      out2[name] = 2
    }else if(x=="out3"){
      out3[name] = 3
    }else if(x=="in1"){
      in1[name] = 1
    }else if(x=="in2"){
      in2[name] = 1
    }else if(x=="in3"){
      in3[name] = 1
    }else if(x=="jump"){
      jump[name] = 1
    }
  }
}

# Assign numbers to all opcodes and output the result.
END {
  cnt = 0

      printf "#define %-25s %15d\n", sprintf( "OP_NotUsed_%-3d", i ), i
    }
  }

  # Generate the bitvectors:
  #
  #  bit 0:     jump
  #  bit 1:     output on P1
  #  bit 2:     output on P2
  #  bit 3:     output on P3
  #  bit 4:     input on P1
  #  bit 5:     input on P2
  #  bit 6:     input on P3
  #  bit 7:     pushes a result onto stack
  #
  for(i=0; i<=max; i++) bv[i] = 0;
  for(name in op){
    x = op[name]
    a0 = a1 = a2 = a3 = a4 = a5 = a6 = a7 = 0
    if( jump[name] ) a0 = 1;
    if( out1[name] ) a1 = 2;
    if( out2[name] ) a2 = 4;
    if( out3[name] ) a3 = 8;
    if( in1[name] ) a4 = 16;
    if( in2[name] ) a5 = 32;
    if( in3[name] ) a6 = 64;
    if( nopush[name]==0 ) a7 = 128;

    bv[x] = a0+a1+a2+a3+a4+a5+a6+a7;
  }
  print "\n"
  print "/* Properties such as \"out2\" or \"jump\" that are specified in"
  print "** comments following the "case" for each opcode in the vdbe.c"
  print "** are encoded into bitvectors as follows:"
  print "*/"
  print "#define OPFLG_JUMP     0x01    /* jump:  P2 holds a jump target */"
  print "#define OPFLG_OUT1     0x02    /* out1:  P1 specifies output reg */"
  print "#define OPFLG_OUT2     0x04    /* out2:  P2 specifies output reg */"
  print "#define OPFLG_OUT3     0x08    /* out3:  P3 specifies output reg */"
  print "#define OPFLG_IN1      0x10    /* in1:   P1 is an input reg */"
  print "#define OPFLG_IN2      0x20    /* in2:   P2 is an input reg */"
  print "#define OPFLG_IN3      0x40    /* in3:   P3 is an input reg */"
  print "#define OPFLG_PUSH     0x80    /* omits no-push:  Does not push */"
  print "#define OPFLG_INITIALIZER {\\"
  for(i=0; i<=max; i++){
    printf " 0x%02x,", bv[i]
    if( i%10==9 ) printf("\\\n");
  }
  print "}"
}

**    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 used to generate VDBE code
** that implements the ALTER TABLE command.
**
** $Id: alter.c,v 1.38 2008/01/04 11:01:04 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** The code in this file only exists if we are not omitting the
** ALTER TABLE logic from the build.

  ** one is defined. The xRename() callback will modify the names
  ** of any resources used by the v-table implementation (including other
  ** SQLite tables) that are identified by the name of the virtual table.
  */
#ifndef SQLITE_OMIT_VIRTUALTABLE
  if( isVirtualRename ){
    int i = ++pParse->nMem;
    sqlite3_value *pVal = sqlite3ValueNew(db);
    sqlite3ValueSetStr(pVal, -1, zName, SQLITE_UTF8, SQLITE_TRANSIENT);
    sqlite3VdbeAddOp4(v, OP_MemSet, i, 0, 0, (char *)pVal, P4_MEM);
    sqlite3VdbeAddOp4(v, OP_VRename, i, 0, 0,(const char*)pTab->pVtab, P4_VTAB);
  }
#endif

  /* figure out how many UTF-8 characters are in zName */
  zTabName = pTab->zName;
  nTabName = sqlite3Utf8CharLen(zTabName, -1);

/*
** 2005 July 8
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains code associated with the ANALYZE command.
**
** @(#) $Id: analyze.c,v 1.30 2008/01/03 18:03:09 drh Exp $
*/
#ifndef SQLITE_OMIT_ANALYZE
#include "sqliteInt.h"

/*
** This routine generates code that opens the sqlite_stat1 table on cursor
** iStatCur.

    **    ...
    **    mem[iMem+nCol+nCol]:   Last observed value of column N
    **
    ** Cells iMem through iMem+nCol are initialized to 0.  The others
    ** are initialized to NULL.
    */
    for(i=0; i<=nCol; i++){
      sqlite3VdbeAddOp2(v, OP_MemInt, 0, iMem+i);
    }
    for(i=0; i<nCol; i++){
      sqlite3VdbeAddOp2(v, OP_MemNull, 0, iMem+nCol+i+1);
    }

    /* Do the analysis.
    */
    endOfLoop = sqlite3VdbeMakeLabel(v);
    sqlite3VdbeAddOp2(v, OP_Rewind, iIdxCur, endOfLoop);
    topOfLoop = sqlite3VdbeCurrentAddr(v);

**     CREATE INDEX
**     DROP INDEX
**     creating ID lists
**     BEGIN TRANSACTION
**     COMMIT
**     ROLLBACK
**
** $Id: build.c,v 1.456 2008/01/03 18:03:09 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.

      sqlite3VdbeAddOp0(v, OP_VBegin);
    }
#endif

    /* If the file format and encoding in the database have not been set, 
    ** set them now.
    */
    sqlite3VdbeAddOp2(v, OP_ReadCookie, iDb, 1);   /* file_format */
    sqlite3VdbeUsesBtree(v, iDb);
    lbl = sqlite3VdbeMakeLabel(v);
    sqlite3VdbeAddOp2(v, OP_If, 0, lbl);
    fileFormat = (db->flags & SQLITE_LegacyFileFmt)!=0 ?
                  1 : SQLITE_MAX_FILE_FORMAT;
    sqlite3VdbeAddOp1(v, OP_Integer, fileFormat);
    sqlite3VdbeAddOp2(v, OP_SetCookie, iDb, 1);

** Generate code to make sure the file format number is at least minFormat.
** The generated code will increase the file format number if necessary.
*/
void sqlite3MinimumFileFormat(Parse *pParse, int iDb, int minFormat){
  Vdbe *v;
  v = sqlite3GetVdbe(pParse);
  if( v ){
    sqlite3VdbeAddOp2(v, OP_ReadCookie, iDb, 1);
    sqlite3VdbeUsesBtree(v, iDb);
    sqlite3VdbeAddOp1(v, OP_Integer, minFormat);
    sqlite3VdbeAddOp2(v, OP_Ge, 0, sqlite3VdbeCurrentAddr(v)+3);
    sqlite3VdbeAddOp1(v, OP_Integer, minFormat);
    sqlite3VdbeAddOp2(v, OP_SetCookie, iDb, 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
** in order to generate code for DELETE FROM statements.
**
** $Id: delete.c,v 1.147 2008/01/04 19:10:29 danielk1977 Exp $
*/
#include "sqliteInt.h"

/*
** Look up every table that is named in pSrc.  If any table is not found,
** add an error message to pParse->zErrMsg and return NULL.  If all tables
** are found, return a pointer to the last table.

  }

  /* Initialize the counter of the number of rows deleted, if
  ** we are counting rows.
  */
  if( db->flags & SQLITE_CountRows ){
    memCnt = ++pParse->nMem;
    sqlite3VdbeAddOp2(v, OP_MemInt, 0, memCnt);
  }

  /* Special case: A DELETE without a WHERE clause deletes everything.
  ** It is easier just to erase the whole table.  Note, however, that
  ** this means that the row change count will be incorrect.
  */
  if( pWhere==0 && !triggers_exist && !IsVirtual(pTab) ){

      */
      sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, iRowid);

      /* Populate the OLD.* pseudo-table */
      if( old_col_mask ){
        sqlite3VdbeAddOp3(v, OP_RowData, iCur, 0, iData);
      }else{
        sqlite3VdbeAddOp2(v, OP_MemNull, 0, iData);
      }
      sqlite3VdbeAddOp3(v, OP_Insert, oldIdx, iData, iRowid);

      /* Jump back and run the BEFORE triggers */
      sqlite3VdbeAddOp2(v, OP_Goto, 0, iBeginBeforeTrigger);
      sqlite3VdbeJumpHere(v, iEndBeforeTrigger);
    }

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains routines used for analyzing expressions and
** for generating VDBE code that evaluates expressions in SQLite.
**
** $Id: expr.c,v 1.329 2008/01/03 23:44:53 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** Return the 'affinity' of the expression pExpr if any.
**

      int iAddr;
      Table *pTab = p->pSrc->a[0].pTab;
      int iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
      sqlite3VdbeUsesBtree(v, iDb);

      sqlite3VdbeAddOp1(v, OP_MemLoad, iMem);
      iAddr = sqlite3VdbeAddOp2(v, OP_If, 0, iMem);
      sqlite3VdbeAddOp2(v, OP_MemInt, 1, iMem);

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

      sqlite3VdbeJumpHere(v, iAddr);
    }else{
      /* The collation sequence used by the comparison. If an index is to 

  
          pKey = (char *)sqlite3IndexKeyinfo(pParse, pIdx);
          iDb = sqlite3SchemaToIndex(db, pIdx->pSchema);
          sqlite3VdbeUsesBtree(v, iDb);

          sqlite3VdbeAddOp1(v, OP_MemLoad, iMem);
          iAddr = sqlite3VdbeAddOp2(v, OP_If, 0, iMem);
          sqlite3VdbeAddOp2(v, OP_MemInt, 1, iMem);
  
          sqlite3VdbeAddOp4(v, OP_OpenRead, iTab, pIdx->tnum, iDb,
                               pKey,P4_KEYINFO_HANDOFF);
          VdbeComment((v, "%s", pIdx->zName));
          eType = IN_INDEX_INDEX;
          sqlite3VdbeAddOp2(v, OP_SetNumColumns, iTab, pIdx->nColumn);

  ** save the results, and reuse the same result on subsequent invocations.
  */
  if( !ExprHasAnyProperty(pExpr, EP_VarSelect) && !pParse->trigStack ){
    int mem = ++pParse->nMem;
    sqlite3VdbeAddOp1(v, OP_MemLoad, mem);
    testAddr = sqlite3VdbeAddOp0(v, OP_If);
    assert( testAddr>0 || pParse->db->mallocFailed );
    sqlite3VdbeAddOp2(v, OP_MemInt, 1, mem);
  }

  switch( pExpr->op ){
    case TK_IN: {
      char affinity;
      KeyInfo keyInfo;
      int addr;        /* Address of OP_OpenEphemeral instruction */

      Select *pSel;
      SelectDest dest;

      pSel = pExpr->pSelect;
      dest.iParm = ++pParse->nMem;
      if( pExpr->op==TK_SELECT ){
        dest.eDest = SRT_Mem;
        sqlite3VdbeAddOp2(v, OP_MemNull, 0, dest.iParm);
        VdbeComment((v, "Init subquery result"));
      }else{
        dest.eDest = SRT_Exists;
        sqlite3VdbeAddOp2(v, OP_MemInt, 0, dest.iParm);
        VdbeComment((v, "Init EXISTS result"));
      }
      sqlite3ExprDelete(pSel->pLimit);
      pSel->pLimit = sqlite3PExpr(pParse, TK_INTEGER, 0, 0, &one);
      if( sqlite3Select(pParse, pSel, &dest, 0, 0, 0, 0) ){
        return;
      }

**    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 1.210 2008/01/04 19:10:29 danielk1977 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:

    int addr;
    assert( v );
    addr = sqlite3VdbeCurrentAddr(v);
    sqlite3OpenTable(pParse, iCur, iDb, pDb->pSchema->pSeqTab, OP_OpenWrite);
    sqlite3VdbeAddOp2(v, OP_MemLoad, memId-1, 0);
    sqlite3VdbeAddOp2(v, OP_NotNull, -1, addr+6);
    sqlite3VdbeAddOp2(v, OP_Pop, 1, 0);
    sqlite3VdbeAddOp2(v, OP_NewRowid, iCur, 0);
    sqlite3VdbeAddOp4(v, OP_String8, 0, 0, 0, pTab->zName, 0);
    sqlite3VdbeAddOp2(v, OP_MemLoad, memId, 0);
    sqlite3VdbeAddOp2(v, OP_MakeRecord, 2, 0);
    sqlite3CodeInsert(pParse, iCur, OPFLAG_APPEND);
    sqlite3VdbeAddOp2(v, OP_Close, iCur, 0);
  }
}

      /* Generate the subroutine that SELECT calls to process each row of
      ** the result.  Store the result in a temporary table
      */
      srcTab = pParse->nTab++;
      sqlite3VdbeResolveLabel(v, iInsertBlock);
      sqlite3VdbeAddOp2(v, OP_StackDepth, -1, 0);
      sqlite3VdbeAddOp2(v, OP_MakeRecord, nColumn, 0);
      sqlite3VdbeAddOp2(v, OP_NewRowid, srcTab, 0);
      sqlite3VdbeAddOp2(v, OP_Pull, 1, 0);
      sqlite3CodeInsert(pParse, srcTab, OPFLAG_APPEND);
      sqlite3VdbeAddOp2(v, OP_Return, 0, 0);

      /* The following code runs first because the GOTO at the very top
      ** of the program jumps to it.  Create the temporary table, then jump
      ** back up and execute the SELECT code above.

    sqlite3VdbeAddOp2(v, OP_SetNumColumns, newIdx, pTab->nCol);
  }
    
  /* Initialize the count of rows to be inserted
  */
  if( db->flags & SQLITE_CountRows ){
    iCntMem = ++pParse->nMem;
    sqlite3VdbeAddOp2(v, OP_MemInt, 0, iCntMem);
  }

  /* If this is not a view, open the table and and all indices */
  if( !isView ){
    base = pParse->nTab;
    sqlite3OpenTableAndIndices(pParse, pTab, base, OP_OpenWrite);
  }

  if( !isView ){
    int iReg = pParse->nMem+1;
    int iRowid = iReg+(IsVirtual(pTab)?1:0);
    pParse->nMem += pTab->nCol + (IsVirtual(pTab)?2:1);

    if( IsVirtual(pTab) ){
      /* The row that the VUpdate opcode will delete: none */
      sqlite3VdbeAddOp2(v, OP_MemNull, 0, iReg);
    }
    if( keyColumn>=0 ){
      if( useTempTable ){
        sqlite3VdbeAddOp3(v, OP_Column, srcTab, keyColumn, iRowid);
      }else if( pSelect ){
        sqlite3VdbeAddOp3(v, OP_Dup, nColumn - keyColumn - 1, 1, iRowid);
        /* TODO: Avoid this use of the stack. */
        sqlite3VdbeAddOp2(v, OP_MemStore, iRowid, 1);
      }else{
        VdbeOp *pOp;
        sqlite3ExprCode(pParse, pList->a[keyColumn].pExpr, 0);
        pOp = sqlite3VdbeGetOp(v, sqlite3VdbeCurrentAddr(v) - 1);
        if( pOp && pOp->opcode==OP_Null ){
          appendFlag = 1;
          pOp->opcode = OP_NewRowid;
          pOp->p1 = base;
          pOp->p2 = counterMem;
          pOp->p3 = iRowid;
        }else{
          /* TODO: Avoid this use of the stack. */
          sqlite3VdbeAddOp2(v, OP_MemStore, iRowid, 1);
        }
      }
      /* If the PRIMARY KEY expression is NULL, then use OP_NewRowid
      ** to generate a unique primary key value.
      */
      if( !appendFlag ){
        sqlite3VdbeAddOp2(v, OP_IfMemNull, iRowid, sqlite3VdbeCurrentAddr(v)+2);
        sqlite3VdbeAddOp2(v, OP_Goto, -1, sqlite3VdbeCurrentAddr(v)+2);
        sqlite3VdbeAddOp3(v, OP_NewRowid, base, counterMem, iRowid);
        sqlite3VdbeAddOp3(v, OP_MustBeInt, 0, 0, iRowid);
      }
    }else if( IsVirtual(pTab) ){
      sqlite3VdbeAddOp2(v, OP_MemNull, 0, iRowid);
    }else{
      sqlite3VdbeAddOp2(v, OP_NewRowid, base, counterMem);
      sqlite3VdbeAddOp2(v, OP_MemStore, iRowid, 1);
      appendFlag = 1;
    }
    autoIncStep(pParse, counterMem, iRowid);

    /* Push onto the stack, data for all columns of the new entry, beginning
    ** with the first column.
    */
    nHidden = 0;
    for(i=0; i<pTab->nCol; i++){
      int iRegStore = iRowid+1+i;
      if( i==pTab->iPKey ){
        /* The value of the INTEGER PRIMARY KEY column is always a NULL.
        ** Whenever this column is read, the record number will be substituted
        ** in its place.  So will fill this column with a NULL to avoid
        ** taking up data space with information that will never be used. */
        sqlite3VdbeAddOp2(v, OP_MemNull, 0, iRegStore);
        continue;
      }
      if( pColumn==0 ){
        if( IsHiddenColumn(&pTab->aCol[i]) ){
          assert( IsVirtual(pTab) );
          j = -1;
          nHidden++;

    sqlite3VdbeAddOp2(v, OP_Dup, 0, 0);
    addr2 = sqlite3VdbeAddOp2(v, OP_NotExists, iDest, 0);
    sqlite3VdbeAddOp4(v, OP_Halt, SQLITE_CONSTRAINT, onError, 0,
                      "PRIMARY KEY must be unique", P4_STATIC);
    sqlite3VdbeJumpHere(v, addr2);
    autoIncStep(pParse, counterMem, 0);
  }else if( pDest->pIndex==0 ){
    addr1 = sqlite3VdbeAddOp2(v, OP_NewRowid, iDest, 0);
  }else{
    addr1 = sqlite3VdbeAddOp2(v, OP_Rowid, iSrc, 0);
    assert( pDest->autoInc==0 );
  }
  sqlite3VdbeAddOp2(v, OP_RowData, iSrc, 0);
  sqlite3CodeInsert(pParse,iDest,OPFLAG_NCHANGE|OPFLAG_LASTROWID|OPFLAG_APPEND);
  sqlite3VdbeChangeP4(v, -1, pDest->zName, 0);

/*
** 2003 April 6
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains code used to implement the PRAGMA command.
**
** $Id: pragma.c,v 1.157 2008/01/03 18:03:09 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/* Ignore this whole file if pragmas are disabled
*/
#if !defined(SQLITE_OMIT_PRAGMA) && !defined(SQLITE_OMIT_PARSER)

/*
** Generate code to return a single integer value.
*/
static void returnSingleInt(Parse *pParse, const char *zLabel, int value){
  Vdbe *v = sqlite3GetVdbe(pParse);
  int mem = ++pParse->nMem;
  sqlite3VdbeAddOp2(v, OP_MemInt, value, mem);
  if( pParse->explain==0 ){
    sqlite3VdbeSetNumCols(v, 1);
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, zLabel, P4_STATIC);
  }
  sqlite3VdbeAddOp2(v, OP_ResultRow, mem, 1);
}

  ** database file.  The cache size is actually the absolute value of
  ** this memory location.  The sign of meta-value 2 determines the
  ** synchronous setting.  A negative value means synchronous is off
  ** and a positive value means synchronous is on.
  */
  if( sqlite3StrICmp(zLeft,"default_cache_size")==0 ){
    static const VdbeOpList getCacheSize[] = {
      { OP_ReadCookie,  0, 2,        0},  /* 0 */
      { OP_AbsValue,    0, 0,        0},
      { OP_Dup,         0, 0,        0},
      { OP_Integer,     0, 0,        0},
      { OP_Ne,          0, 6,        0},
      { OP_Integer,     0, 0,        0},  /* 5 */
      { OP_Callback,    1, 0,        0},
    };

      sqlite3VdbeChangeP1(v, addr, iDb);
      sqlite3VdbeChangeP1(v, addr+5, SQLITE_DEFAULT_CACHE_SIZE);
    }else{
      int size = atoi(zRight);
      if( size<0 ) size = -size;
      sqlite3BeginWriteOperation(pParse, 0, iDb);
      sqlite3VdbeAddOp2(v, OP_Integer, size, 0);
      sqlite3VdbeAddOp2(v, OP_ReadCookie, iDb, 2);
      addr = sqlite3VdbeAddOp2(v, OP_Integer, 0, 0);
      sqlite3VdbeAddOp2(v, OP_Ge, 0, addr+3);
      sqlite3VdbeAddOp2(v, OP_Negative, 0, 0);
      sqlite3VdbeAddOp2(v, OP_SetCookie, iDb, 2);
      pDb->pSchema->cache_size = size;
      sqlite3BtreeSetCacheSize(pDb->pBt, pDb->pSchema->cache_size);
    }

          /* When setting the auto_vacuum mode to either "full" or 
          ** "incremental", write the value of meta[6] in the database
          ** file. Before writing to meta[6], check that meta[3] indicates
          ** that this really is an auto-vacuum capable database.
          */
          static const VdbeOpList setMeta6[] = {
            { OP_Transaction,    0,               1,        0},    /* 0 */
            { OP_ReadCookie,     0,               3,        0},    /* 1 */
            { OP_If,             0,               0,        0},    /* 2 */
            { OP_Halt,           SQLITE_OK,       OE_Abort, 0},    /* 3 */
            { OP_Integer,        0,               0,        0},    /* 4 */
            { OP_SetCookie,      0,               6,        0},    /* 5 */
          };
          int iAddr;
          iAddr = sqlite3VdbeAddOpList(v, ArraySize(setMeta6), setMeta6);

    if( sqlite3ReadSchema(pParse) ){
      goto pragma_out;
    }
    if( zRight==0 || !sqlite3GetInt32(zRight, &iLimit) || iLimit<=0 ){
      iLimit = 0x7fffffff;
    }
    sqlite3BeginWriteOperation(pParse, 0, iDb);
    sqlite3VdbeAddOp2(v, OP_MemInt, iLimit, 1);
    addr = sqlite3VdbeAddOp2(v, OP_IncrVacuum, iDb, 0);
    sqlite3VdbeAddOp2(v, OP_Callback, 0, 0);
    sqlite3VdbeAddOp2(v, OP_MemIncr, -1, 1);
    sqlite3VdbeAddOp2(v, OP_IfMemPos, 1, addr);
    sqlite3VdbeJumpHere(v, addr);
  }else
#endif

    mxErr = SQLITE_INTEGRITY_CHECK_ERROR_MAX;
    if( zRight ){
      mxErr = atoi(zRight);
      if( mxErr<=0 ){
        mxErr = SQLITE_INTEGRITY_CHECK_ERROR_MAX;
      }
    }
    sqlite3VdbeAddOp2(v, OP_MemInt, mxErr, 1);

    /* Do an integrity check on each database file */
    for(i=0; i<db->nDb; i++){
      HashElem *x;
      Hash *pTbls;
      int cnt = 0;

        int loopTop;

        if( pTab->pIndex==0 ) continue;
        addr = sqlite3VdbeAddOp2(v, OP_IfMemPos, 1, 0);
        sqlite3VdbeAddOp2(v, OP_Halt, 0, 0);
        sqlite3VdbeJumpHere(v, addr);
        sqlite3OpenTableAndIndices(pParse, pTab, 1, OP_OpenRead);
        sqlite3VdbeAddOp2(v, OP_MemInt, 0, 2);
        loopTop = sqlite3VdbeAddOp2(v, OP_Rewind, 1, 0);
        sqlite3VdbeAddOp2(v, OP_MemIncr, 1, 2);
        for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
          int jmp2;
          static const VdbeOpList idxErr[] = {
            { OP_MemIncr,    -1,  1,  0},
            { OP_String8,     0,  0,  0},    /* 1 */

          sqlite3VdbeChangeP4(v, addr+4, pIdx->zName, P4_STATIC);
          sqlite3VdbeJumpHere(v, jmp2);
        }
        sqlite3VdbeAddOp2(v, OP_Next, 1, loopTop+1);
        sqlite3VdbeJumpHere(v, loopTop);
        for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
          static const VdbeOpList cntIdx[] = {
             { OP_MemInt,       0,  3,  0},
             { OP_Rewind,       0,  0,  0},  /* 1 */
             { OP_MemIncr,      1,  3,  0},
             { OP_Next,         0,  0,  0},  /* 3 */
             { OP_MemLoad,      2,  0,  0},
             { OP_MemLoad,      3,  0,  0},
             { OP_Eq,           0,  0,  0},  /* 6 */
             { OP_MemIncr,     -1,  1,  0},

      /* Read the specified cookie value */
      static const VdbeOpList readCookie[] = {
        { OP_ReadCookie,      0,  0,  0},    /* 0 */
        { OP_Callback,        1,  0,  0}
      };
      int addr = sqlite3VdbeAddOpList(v, ArraySize(readCookie), readCookie);
      sqlite3VdbeChangeP1(v, addr, iDb);
      sqlite3VdbeChangeP2(v, addr, iCookie);
      sqlite3VdbeSetNumCols(v, 1);
      sqlite3VdbeSetColName(v, 0, COLNAME_NAME, zLeft, P4_TRANSIENT);
    }
  }else
#endif /* SQLITE_OMIT_SCHEMA_VERSION_PRAGMAS */

#if defined(SQLITE_DEBUG) || defined(SQLITE_TEST)

**    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 SELECT statements in SQLite.
**
** $Id: select.c,v 1.383 2008/01/03 23:44:53 drh Exp $
*/
#include "sqliteInt.h"


/*
** Delete all the content of a Select structure but do not deallocate
** the select structure itself.

  if( nColumn>0 ){
    n = nColumn;
  }else{
    n = pEList->nExpr;
  }
  iMem = ++pParse->nMem;
  pParse->nMem += n+1;
  sqlite3VdbeAddOp2(v, OP_MemInt, n, iMem);
  if( nColumn>0 ){
    for(i=0; i<nColumn; i++){
      sqlite3VdbeAddOp3(v, OP_Column, srcTab, i, iMem+i+1);
    }
  }else if( eDest!=SRT_Exists ){
    /* If the destination is an EXISTS(...) expression, the actual
    ** values returned by the SELECT are not required.

    */
    case SRT_Table:
    case SRT_EphemTab: {
      sqlite3VdbeAddOp2(v, OP_RegMakeRec, iMem, 0);
      if( pOrderBy ){
        pushOntoSorter(pParse, pOrderBy, p);
      }else{
        sqlite3VdbeAddOp2(v, OP_NewRowid, iParm, 0);
        sqlite3VdbeAddOp2(v, OP_Pull, 1, 0);
        sqlite3CodeInsert(pParse, iParm, OPFLAG_APPEND);
      }
      break;
    }

#ifndef SQLITE_OMIT_SUBQUERY

      sqlite3VdbeJumpHere(v, addr2);
      break;
    }

    /* If any row exist in the result set, record that fact and abort.
    */
    case SRT_Exists: {
      sqlite3VdbeAddOp2(v, OP_MemInt, 1, iParm);
      /* The LIMIT clause will terminate the loop for us */
      break;
    }

    /* If this is a scalar select that is part of an expression, then
    ** store the results in the appropriate memory cell and break out
    ** of the scan loop.

  if( eDest==SRT_Callback || eDest==SRT_Subroutine ){
    sqlite3VdbeAddOp2(v, OP_Integer, 1, 0);
  }
  sqlite3VdbeAddOp2(v, OP_Column, iTab, pOrderBy->nExpr + 1);
  switch( eDest ){
    case SRT_Table:
    case SRT_EphemTab: {
      sqlite3VdbeAddOp2(v, OP_NewRowid, iParm, 0);
      sqlite3VdbeAddOp2(v, OP_Pull, 1, 0);
      sqlite3CodeInsert(pParse, iParm, OPFLAG_APPEND);
      break;
    }
#ifndef SQLITE_OMIT_SUBQUERY
    case SRT_Set: {
      assert( nColumn==1 );

    if( p->pLimit ){
      sqlite3VdbeAddOp2(v, OP_Add, 0, 0);
    }
  }
  if( p->pLimit ){
    addr1 = sqlite3VdbeAddOp2(v, OP_IfMemPos, iLimit, 0);
    sqlite3VdbeAddOp2(v, OP_Pop, 1, 0);
    sqlite3VdbeAddOp2(v, OP_MemInt, -1, iLimit+1);
    addr2 = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0);
    sqlite3VdbeJumpHere(v, addr1);
    sqlite3VdbeAddOp2(v, OP_MemStore, iLimit+1, 1);
    VdbeComment((v, "LIMIT+OFFSET"));
    sqlite3VdbeJumpHere(v, addr2);
  }
}

  Vdbe *v = pParse->pVdbe;
  int i;
  struct AggInfo_func *pFunc;
  if( pAggInfo->nFunc+pAggInfo->nColumn==0 ){
    return;
  }
  for(i=0; i<pAggInfo->nColumn; i++){
    sqlite3VdbeAddOp2(v, OP_MemNull, 0, pAggInfo->aCol[i].iMem);
  }
  for(pFunc=pAggInfo->aFunc, i=0; i<pAggInfo->nFunc; i++, pFunc++){
    sqlite3VdbeAddOp2(v, OP_MemNull, 0, pFunc->iMem);
    if( pFunc->iDistinct>=0 ){
      Expr *pE = pFunc->pExpr;
      if( pE->pList==0 || pE->pList->nExpr!=1 ){
        sqlite3ErrorMsg(pParse, "DISTINCT in aggregate must be followed "
           "by an expression");
        pFunc->iDistinct = -1;
      }else{

      */
      iUseFlag = ++pParse->nMem;
      iAbortFlag = ++pParse->nMem;
      iAMem = pParse->nMem + 1;
      pParse->nMem += pGroupBy->nExpr;
      iBMem = pParse->nMem + 1;
      pParse->nMem += pGroupBy->nExpr;
      sqlite3VdbeAddOp2(v, OP_MemInt, 0, iAbortFlag);
      VdbeComment((v, "clear abort flag"));
      sqlite3VdbeAddOp2(v, OP_MemInt, 0, iUseFlag);
      VdbeComment((v, "indicate accumulator empty"));
      sqlite3VdbeAddOp2(v, OP_Goto, 0, addrInitializeLoop);

      /* Generate a subroutine that outputs a single row of the result
      ** set.  This subroutine first looks at the iUseFlag.  If iUseFlag
      ** is less than or equal to zero, the subroutine is a no-op.  If
      ** the processing calls for the query to abort, this subroutine
      ** increments the iAbortFlag memory location before returning in
      ** order to signal the caller to abort.
      */
      addrSetAbort = sqlite3VdbeCurrentAddr(v);
      sqlite3VdbeAddOp2(v, OP_MemInt, 1, iAbortFlag);
      VdbeComment((v, "set abort flag"));
      sqlite3VdbeAddOp2(v, OP_Return, 0, 0);
      addrOutputRow = sqlite3VdbeCurrentAddr(v);
      sqlite3VdbeAddOp2(v, OP_IfMemPos, iUseFlag, addrOutputRow+2);
      VdbeComment((v, "Groupby result generator entry point"));
      sqlite3VdbeAddOp2(v, OP_Return, 0, 0);
      finalizeAggFunctions(pParse, &sAggInfo);

      VdbeComment((v, "reset accumulator"));

      /* Update the aggregate accumulators based on the content of
      ** the current row
      */
      sqlite3VdbeResolveLabel(v, addrProcessRow);
      updateAccumulator(pParse, &sAggInfo);
      sqlite3VdbeAddOp2(v, OP_MemInt, 1, iUseFlag);
      VdbeComment((v, "indicate data in accumulator"));

      /* End of the loop
      */
      if( groupBySort ){
        sqlite3VdbeAddOp2(v, OP_Next, sAggInfo.sortingIdx, addrTopOfLoop);
      }else{

**    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 UPDATE statements.
**
** $Id: update.c,v 1.157 2008/01/04 19:10:29 danielk1977 Exp $
*/
#include "sqliteInt.h"

#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Forward declaration */
static void updateVirtualTable(
  Parse *pParse,       /* The parsing context */

  */
  sqlite3WhereEnd(pWInfo);

  /* Initialize the count of updated rows
  */
  if( db->flags & SQLITE_CountRows && !pParse->trigStack ){
    memCnt = ++pParse->nMem;
    sqlite3VdbeAddOp2(v, OP_MemInt, 0, memCnt);
  }

  if( !isView && !IsVirtual(pTab) ){
    /* 
    ** Open every index that needs updating.  Note that if any
    ** index could potentially invoke a REPLACE conflict resolution 
    ** action, then we need to open all indices because we might need

**
** 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.
**
** $Id: vdbe.c,v 1.678 2008/01/04 19:10:29 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>
#include "vdbeInt.h"

/*
** The following global variable is incremented every time a cursor

}

/*
** Properties of opcodes.  The OPFLG_INITIALIZER macro is
** created by mkopcodeh.awk during compilation.  Data is obtained
** from the comments following the "case OP_xxxx:" statements in
** this file.  
**
**      jump:      OPFLG_JUMP
**      out1:      OPFLG_OUT1
**      out2:      OPFLG_OUT2
**      out3:      OPFLG_OUT3
**      in1:       OPFLG_IN1
**      in2:       OPFLG_IN2
**      in3:       OPFLG_IN3
*/
static unsigned char opcodeProperty[] = OPFLG_INITIALIZER;

/*
** Return true if an opcode has any of the OPFLG_xxx properties
** specified by mask.
*/

){
  int pc;                    /* The program counter */
  Op *pOp;                   /* Current operation */
  int rc = SQLITE_OK;        /* Value to return */
  sqlite3 *db = p->db;       /* The database */
  u8 encoding = ENC(db);     /* The database encoding */
  Mem *pTos;                 /* Top entry in the operand stack */



#ifdef VDBE_PROFILE
  unsigned long long start;  /* CPU clock count at start of opcode */
  int origPc;                /* Program counter at start of opcode */
#endif
#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
  int nProgressOps = 0;      /* Opcodes executed since progress callback. */
#endif

    */ 
    pStackLimit = pTos;
    if( sqlite3VdbeOpcodeHasProperty(pOp->opcode, OPFLG_PUSH) ){
      pStackLimit++;
    }
    assert( pTos>=&p->aStack[-1] && pTos<=pStackLimit );
#endif




















    switch( pOp->opcode ){

/*****************************************************************************
** What follows is a massive switch statement where each case implements a
** separate instruction in the virtual machine.  If we follow the usual
** indentation conventions, each case should be indented by 6 spaces.  But

    p->errorAction = OE_Rollback;
    sqlite3SetString(&p->zErrMsg, "internal error: VDBE stack leak", (char*)0);
    goto vdbe_return;
  }
  break;
}

/* Opcode: Integer P1 * *
**
** The 32-bit integer value P1 is pushed onto the stack.

*/
case OP_Integer: {
  pTos++;
  pTos->flags = MEM_Int;
  pTos->u.i = pOp->p1;
  break;
}

/* Opcode: Int64 * * P4
**
** P4 is a pointer to a 64-bit integer value.
** Push  that value onto  the stack.
*/
case OP_Int64: {
  pTos++;
  assert( pOp->p4.pI64!=0 );
  pTos->flags = MEM_Int;
  memcpy(&pTos->u.i, pOp->p4.pI64, 8);
  break;
}

/* Opcode: Real * * P4
**
** P4 is a pointer to a 64-bit floating point value.  Push that value
** onto the stack.
*/
case OP_Real: {            /* same as TK_FLOAT, */
  pTos++;
  pTos->flags = MEM_Real;
  memcpy(&pTos->r, pOp->p4.pReal, 8);
  break;
}

/* Opcode: String8 * * 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.
*/
case OP_String8: {         /* same as TK_STRING */
  assert( pOp->p4.z!=0 );
  pOp->opcode = OP_String;
  pOp->p1 = strlen(pOp->p4.z);

#ifndef SQLITE_OMIT_UTF16
  if( encoding!=SQLITE_UTF8 ){
    pTos++;
    sqlite3VdbeMemSetStr(pTos, pOp->p4.z, -1, SQLITE_UTF8, SQLITE_STATIC);
    if( SQLITE_OK!=sqlite3VdbeChangeEncoding(pTos, encoding) ) goto no_mem;
    if( SQLITE_OK!=sqlite3VdbeMemDynamicify(pTos) ) goto no_mem;
    pTos->flags &= ~(MEM_Dyn);
    pTos->flags |= MEM_Static;
    if( pOp->p4type==P4_DYNAMIC ){
      sqlite3_free(pOp->p4.z);
    }
    pOp->p4type = P4_DYNAMIC;
    pOp->p4.z = pTos->z;
    pOp->p1 = pTos->n;
    if( pOp->p1>SQLITE_MAX_LENGTH ){
      goto too_big;
    }
    break;
  }
#endif
  if( pOp->p1>SQLITE_MAX_LENGTH ){
    goto too_big;
  }
  /* Fall through to the next case, OP_String */
}
  
/* Opcode: String P1 * P4
**
** The string value P4 of length P1 (bytes) is pushed onto the stack.

*/
case OP_String: {
  pTos++;
  assert( pOp->p4.z!=0 );
  pTos->flags = MEM_Str|MEM_Static|MEM_Term;
  pTos->z = pOp->p4.z;
  pTos->n = pOp->p1;
  pTos->enc = encoding;
  break;
}

/* Opcode: Null * * *
**
** Push a NULL onto the stack.

*/
case OP_Null: {
  pTos++;
  pTos->flags = MEM_Null;
  pTos->n = 0;
  break;
}


#ifndef SQLITE_OMIT_BLOB_LITERAL
/* Opcode: HexBlob * * P4
**
** P4 is an UTF-8 SQL hex encoding of a blob. The blob is pushed onto the
** vdbe stack.
**
** The first time this instruction executes, in transforms itself into a
** 'Blob' opcode with a binary blob as P4.
*/
case OP_HexBlob: {            /* same as TK_BLOB */
  pOp->opcode = OP_Blob;
  pOp->p1 = strlen(pOp->p4.z)/2;
  if( pOp->p1>SQLITE_MAX_LENGTH ){
    goto too_big;
  }
  if( pOp->p1 ){
    char *zBlob = sqlite3HexToBlob(db, pOp->p4.z);

** P4 points to a blob of data P1 bytes long. Push this
** value onto the stack. This instruction is not coded directly
** by the compiler. Instead, the compiler layer specifies
** an OP_HexBlob opcode, with the hex string representation of
** the blob as P4. This opcode is transformed to an OP_Blob
** the first time it is executed.
*/
case OP_Blob: {
  pTos++;
  assert( pOp->p1 <= SQLITE_MAX_LENGTH );
  sqlite3VdbeMemSetStr(pTos, pOp->p4.z, pOp->p1, 0, 0);
  pTos->enc = encoding;
  break;
}
#endif /* SQLITE_OMIT_BLOB_LITERAL */

/* Opcode: Variable P1 * *
**
** Push the value of variable P1 onto the stack.  A variable is

** an unknown in the original SQL string as handed to sqlite3_compile().
** Any occurance of the '?' character in the original SQL is considered
** a variable.  Variables in the SQL string are number from left to
** right beginning with 1.  The values of variables are set using the
** sqlite3_bind() API.
*/
case OP_Variable: {
  int j = pOp->p1 - 1;
  Mem *pVar;
  assert( j>=0 && j<p->nVar );

  pVar = &p->aVar[j];
  if( sqlite3VdbeMemTooBig(pVar) ){
    goto too_big;
  }
  pTos++;
  sqlite3VdbeMemShallowCopy(pTos, &p->aVar[j], MEM_Static);
  break;
}

/* Opcode: Pop P1 * *
**
** P1 elements are popped off of the top of stack and discarded.
*/

    if( rc!=SQLITE_OK && rc!=SQLITE_READONLY /* && rc!=SQLITE_BUSY */ ){
      goto abort_due_to_error;
    }
  }
  break;
}

/* Opcode: ReadCookie P1 P2 *
**

** Read cookie number P2 from database P1 and push it onto the stack.
** P2==0 is the schema version.  P2==1 is the database format.
** P2==2 is the recommended pager cache size, and so forth.  P1==0 is
** the main database file and P1==1 is the database file used to store
** temporary tables.
**
** If P1 is negative, then this is a request to read the size of a
** databases free-list. P2 must be set to 1 in this case. The actual
** database accessed is ((P1+1)*-1). For example, a P1 parameter of -1
** corresponds to database 0 ("main"), a P1 of -2 is database 1 ("temp").
**
** There must be a read-lock on the database (either a transaction
** must be started or there must be an open cursor) before
** executing this instruction.
*/
case OP_ReadCookie: {
  int iMeta;
  int iDb = pOp->p1;
  int iCookie = pOp->p2;

  assert( pOp->p2<SQLITE_N_BTREE_META );
  if( iDb<0 ){
    iDb = (-1*(iDb+1));
    iCookie *= -1;
  }
  assert( iDb>=0 && iDb<db->nDb );
  assert( db->aDb[iDb].pBt!=0 );
  assert( (p->btreeMask & (1<<iDb))!=0 );
  /* The indexing of meta values at the schema layer is off by one from
  ** the indexing in the btree layer.  The btree considers meta[0] to
  ** be the number of free pages in the database (a read-only value)
  ** and meta[1] to be the schema cookie.  The schema layer considers
  ** meta[1] to be the schema cookie.  So we have to shift the index
  ** by one in the following statement.
  */
  rc = sqlite3BtreeGetMeta(db->aDb[iDb].pBt, 1 + iCookie, (u32 *)&iMeta);
  pTos++;
  pTos->u.i = iMeta;
  pTos->flags = MEM_Int;
  break;
}

/* Opcode: SetCookie P1 P2 *
**
** Write the top of the stack into cookie number P2 of database P1.
** P2==0 is the schema version.  P2==1 is the database format.

  if( pOp->p3==0 ){
    Release(pTos);
    pTos--;
  }
  break;
}

/* Opcode: Sequence P1 * *
**
** Push an integer onto the stack which is the next available
** sequence number for cursor P1.  The sequence number on the

** cursor is incremented after the push.

*/
case OP_Sequence: {
  int i = pOp->p1;
  assert( pTos>=p->aStack );
  assert( i>=0 && i<p->nCursor );
  assert( p->apCsr[i]!=0 );
  pTos++;
  pTos->u.i = p->apCsr[i]->seqCount++;
  pTos->flags = MEM_Int;
  break;
}


/* Opcode: NewRowid P1 P2 P3
**
** Get a new integer record number (a.k.a "rowid") used as the key to a table.
** The record number is not previously used as a key in the database
** table that cursor P1 points to.  The new record number is pushed 
** onto the stack if P3 is 0 or written to memory cell P3 otherwise.
**
** If P2>0 then P2 is a memory cell that holds the largest previously
** generated record number.  No new record numbers are allowed to be less
** than this value.  When this value reaches its maximum, a SQLITE_FULL
** error is generated.  The P2 memory cell is updated with the generated
** record number.  This P2 mechanism is used to help implement the
** AUTOINCREMENT feature.
*/
case OP_NewRowid: {
  int i = pOp->p1;
  i64 v = 0;
  Cursor *pC;
  assert( i>=0 && i<p->nCursor );
  assert( p->apCsr[i]!=0 );
  if( (pC = p->apCsr[i])->pCursor==0 ){
    /* The zero initialization above is all that is needed */

          }else{
            v++;
          }
        }
      }

#ifndef SQLITE_OMIT_AUTOINCREMENT
      if( pOp->p2 ){
        Mem *pMem;
        assert( pOp->p2>0 && pOp->p2<=p->nMem ); /* P2 is a valid memory cell */
        pMem = &p->aMem[pOp->p2];
        sqlite3VdbeMemIntegerify(pMem);
        assert( (pMem->flags & MEM_Int)!=0 );  /* mem(P2) holds an integer */
        if( pMem->u.i==MAX_ROWID || pC->useRandomRowid ){
          rc = SQLITE_FULL;
          goto abort_due_to_error;
        }
        if( v<pMem->u.i+1 ){
          v = pMem->u.i + 1;
        }
        pMem->u.i = v;
      }
#endif

      if( v<MAX_ROWID ){
        pC->nextRowidValid = 1;
        pC->nextRowid = v+1;
      }else{
        pC->nextRowidValid = 0;
      }
    }
    if( pC->useRandomRowid ){
      assert( pOp->p2==0 );  /* SQLITE_FULL must have occurred prior to this */
      v = db->priorNewRowid;
      cnt = 0;
      do{
        if( v==0 || cnt>2 ){
          sqlite3Randomness(sizeof(v), &v);
          if( cnt<5 ) v &= 0xffffff;
        }else{

        goto abort_due_to_error;
      }
    }
    pC->rowidIsValid = 0;
    pC->deferredMoveto = 0;
    pC->cacheStatus = CACHE_STALE;
  }
  if( pOp->p3 ){
    sqlite3VdbeMemSetInt64(&p->aMem[pOp->p3], v);
  }else{
    pTos++;
    pTos->u.i = v;
    pTos->flags = MEM_Int;
  }
  break;
}

/* Opcode: Insert P1 P2 P3 P4 P5
**
** Write an entry into the table of cursor P1.  A new entry is
** created if it doesn't already exist or the data for an existing

  pOut->enc = SQLITE_UTF8;  /* In case the blob is ever cast to text */
  break;
}

/* Opcode: Rowid P1 P2 * * *
**
** Store in register P2 an integer which is the key of the table entry that
** P1 is currently point to.  If p2==0 then pust the integer.
*/
case OP_Rowid: {
  int i = pOp->p1;
  Cursor *pC;
  i64 v;
  Mem *pDest;

  assert( i>=0 && i<p->nCursor );
  pC = p->apCsr[i];
  assert( pC!=0 );
  rc = sqlite3VdbeCursorMoveto(pC);
  if( rc ) goto abort_due_to_error;
  if( pOp->p2>0 ){
    assert( pOp->p2<=p->nMem );
    pDest = &p->aMem[pOp->p2];
    sqlite3VdbeMemRelease(pDest);
  }else{
    pDest = ++pTos;
  }
  if( pC->rowidIsValid ){
    v = pC->lastRowid;
  }else if( pC->pseudoTable ){
    v = keyToInt(pC->iKey);
  }else if( pC->nullRow || pC->pCursor==0 ){
    pDest->flags = MEM_Null;
    break;
  }else{
    assert( pC->pCursor!=0 );
    sqlite3BtreeKeySize(pC->pCursor, &v);
    v = keyToInt(v);
  }
  pDest->u.i = v;
  pDest->flags = MEM_Int;
  break;
}

/* Opcode: NullRow P1 * *
**
** Move the cursor P1 to a null row.  Any OP_Column operations
** that occur while the cursor is on the null row will always push 

**
** Write into register P2 an integer which is the last entry in the record at
** the end of the index key pointed to by cursor P1.  This integer should be
** the rowid of the table entry to which this index entry points.
**
** See also: Rowid, MakeIdxRec.
*/
case OP_IdxRowid: {
  int i = pOp->p1;
  BtCursor *pCrsr;
  Cursor *pC;
  Mem *pDest;

  assert( i>=0 && i<p->nCursor );
  assert( p->apCsr[i]!=0 );
  if( pOp->p2>0 ){
    assert( pOp->p2<=p->nMem );
    pDest = &p->aMem[pOp->p2];
    sqlite3VdbeMemRelease(pDest);
  }else{
    pDest = ++pTos;
  }
  pDest->flags = MEM_Null;
  if( (pCrsr = (pC = p->apCsr[i])->pCursor)!=0 ){
    i64 rowid;

    assert( pC->deferredMoveto==0 );
    assert( pC->isTable==0 );
    if( pC->nullRow ){
      pDest->flags = MEM_Null;
    }else{
      rc = sqlite3VdbeIdxRowid(pCrsr, &rowid);
      if( rc!=SQLITE_OK ){
        goto abort_due_to_error;
      }
      pDest->flags = MEM_Int;
      pDest->u.i = rowid;
    }
  }
  break;
}

/* Opcode: IdxGT P1 P2 *
**

  }
#endif
  assert( (p->btreeMask & (1<<pOp->p2))!=0 );
  rc = sqlite3BtreeClearTable(db->aDb[pOp->p2].pBt, pOp->p1);
  break;
}

/* Opcode: CreateTable P1 * *
**
** Allocate a new table in the main database file if P2==0 or in the
** auxiliary database file if P2==1.  Push the page number
** for the root page of the new table onto the stack.

**
** The difference between a table and an index is this:  A table must
** have a 4-byte integer key and can have arbitrary data.  An index
** has an arbitrary key but no data.
**
** See also: CreateIndex
*/
/* Opcode: CreateIndex P1 * *
**
** Allocate a new index in the main database file if P2==0 or in the
** auxiliary database file if P2==1.  Push the page number of the

** root page of the new index onto the stack.
**
** See documentation on OP_CreateTable for additional information.
*/
case OP_CreateIndex:
case OP_CreateTable: {
  int pgno;
  int flags;
  Db *pDb;
  assert( pOp->p1>=0 && pOp->p1<db->nDb );
  assert( (p->btreeMask & (1<<pOp->p1))!=0 );
  pDb = &db->aDb[pOp->p1];
  assert( pDb->pBt!=0 );
  if( pOp->opcode==OP_CreateTable ){
    /* flags = BTREE_INTKEY; */
    flags = BTREE_LEAFDATA|BTREE_INTKEY;
  }else{
    flags = BTREE_ZERODATA;
  }
  rc = sqlite3BtreeCreateTable(pDb->pBt, &pgno, flags);
  pTos++;
  if( rc==SQLITE_OK ){
    pTos->u.i = pgno;
    pTos->flags = MEM_Int;
  }else{
    pTos->flags = MEM_Null;
  }
  break;
}

/* Opcode: ParseSchema P1 P2 P4
**
** Read and parse all entries from the SQLITE_MASTER table of database P1

  assert( i>0 && i<=p->nMem );
  if( p->aMem[i].flags & MEM_Null ){
     pc = pOp->p2 - 1;
  }
  break;
}

/* Opcode: MemNull * P2 *
**
** Store a NULL in memory cell P2
*/
case OP_MemNull: {
  assert( pOp->p2>0 && pOp->p2<=p->nMem );
  sqlite3VdbeMemSetNull(&p->aMem[pOp->p2]);
  break;
}

/* Opcode: MemInt P1 P2 *
**
** Store the integer value P1 in memory cell P2.
*/
case OP_MemInt: {
  assert( pOp->p2>0 && pOp->p2<=p->nMem );
  sqlite3VdbeMemSetInt64(&p->aMem[pOp->p2], pOp->p1);
  break;
}

/* Opcode: MemMove P1 P2 *
**
** Move the content of memory cell P2 over to memory cell P1.
** Any prior content of P1 is erased.  Memory cell P2 is left
** containing a NULL.
*/
case OP_MemMove: {
  assert( pOp->p1>0 && pOp->p1<=p->nMem );
  assert( pOp->p2>0 && pOp->p2<=p->nMem );
  rc = sqlite3VdbeMemMove(&p->aMem[pOp->p1], &p->aMem[pOp->p2]);
  break;
}

/* Opcode: MemSet P1 * * P4
**
** The P4 should be set to contain a P4_MEM value. The value is copied
** to memory cell P1.
*/
case OP_MemSet: {
  assert( pOp->p1>0 && pOp->p1<=p->nMem );
  assert( pOp->p4type==P4_MEM );
  rc = sqlite3VdbeMemCopy(&p->aMem[pOp->p1], pOp->p4.pMem);
  break;
}

/* Opcode: AggStep P1 P2 P4
**
** Execute the step function for an aggregate.  The
** function has P2 arguments.  P4 is a pointer to the FuncDef
** structure that specifies the function.  Use memory location
** P1 as the accumulator.
**

#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VRowid P1 P2 *
**
** Store into register P2  the rowid of
** the virtual-table that the P1 cursor is pointing to.
** If P2==0, push the value onto the stack.
*/
case OP_VRowid: {
  const sqlite3_module *pModule;

  Cursor *pCur = p->apCsr[pOp->p1];
  assert( pCur->pVtabCursor );
  pModule = pCur->pVtabCursor->pVtab->pModule;
  if( pModule->xRowid==0 ){
    sqlite3SetString(&p->zErrMsg, "Unsupported module operation: xRowid", 0);
    rc = SQLITE_ERROR;
  } else {
    sqlite_int64 iRow;
    Mem *pDest;

    if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
    rc = pModule->xRowid(pCur->pVtabCursor, &iRow);
    if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;

    if( pOp->p2>0 ){
      assert( pOp->p2<=p->nMem );
      pDest = &p->aMem[pOp->p2];
      sqlite3VdbeMemRelease(pDest);
    }else{
      pDest = ++pTos;
    }
    pDest->flags = MEM_Int;
    pDest->u.i = iRow;
  }

  break;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */

#ifndef SQLITE_OMIT_VIRTUALTABLE

      doesStatementRollback = 1;
#ifndef SQLITE_OMIT_VIRTUALTABLE
    }else if( opcode==OP_VUpdate || opcode==OP_VRename ){
      doesStatementRollback = 1;
    }else if( opcode==OP_VFilter ){
      int n;
      assert( p->nOp - i >= 3 );
      assert( pOp[-1].opcode==OP_MemInt );
      n = pOp[-1].p1;
      if( n>nMaxArgs ) nMaxArgs = n;
#endif
    }
    if( !sqlite3VdbeOpcodeHasProperty(opcode, OPFLG_PUSH) ){
      nMaxStack--;
    }

** This module contains C code that generates VDBE code used to process
** the WHERE clause of SQL statements.  This module is reponsible for
** generating the code that loops through a table looking for applicable
** rows.  Indices are selected and used to speed the search when doing
** so is applicable.  Because this module is responsible for selecting
** indices, you might also think of this module as the "query optimizer".
**
** $Id: where.c,v 1.272 2008/01/03 23:44:53 drh Exp $
*/
#include "sqliteInt.h"

/*
** The number of bits in a Bitmask.  "BMS" means "BitMask Size".
*/
#define BMS  (sizeof(Bitmask)*8)

    /* If this is the right table of a LEFT OUTER JOIN, allocate and
    ** initialize a memory cell that records if this table matches any
    ** row of the left table of the join.
    */
    if( pLevel->iFrom>0 && (pTabItem[0].jointype & JT_LEFT)!=0 ){
      pLevel->iLeftJoin = ++pParse->nMem;
      sqlite3VdbeAddOp2(v, OP_MemInt, 0, pLevel->iLeftJoin);
      VdbeComment((v, "init LEFT JOIN no-match flag"));
    }

#ifndef SQLITE_OMIT_VIRTUALTABLE
    if( pLevel->pBestIdx ){
      /* Case 0:  The table is a virtual-table.  Use the VFilter and VNext
      **          to access the data.

          }
        }
        if( k==nConstraint ) break;
      }
      iReg = ++pParse->nMem;
      pParse->nMem++;
      sqlite3StackToReg(pParse, j-1);
      sqlite3VdbeAddOp2(v, OP_MemInt, pBestIdx->idxNum, iReg);
      sqlite3VdbeAddOp2(v, OP_MemInt, j-1, iReg+1);
      sqlite3VdbeAddOp4(v, OP_VFilter, iCur, brk, iReg, pBestIdx->idxStr,
                        pBestIdx->needToFreeIdxStr ? P4_MPRINTF : P4_STATIC);
      pBestIdx->needToFreeIdxStr = 0;
      for(j=0; j<pBestIdx->nConstraint; j++){
        if( aUsage[j].omit ){
          int iTerm = aConstraint[j].iTermOffset;
          disableTerm(pLevel, &wc.a[iTerm]);

    }

    /* For a LEFT OUTER JOIN, generate code that will record the fact that
    ** at least one row of the right table has matched the left table.  
    */
    if( pLevel->iLeftJoin ){
      pLevel->top = sqlite3VdbeCurrentAddr(v);
      sqlite3VdbeAddOp2(v, OP_MemInt, 1, pLevel->iLeftJoin);
      VdbeComment((v, "record LEFT JOIN hit"));
      for(pTerm=wc.a, j=0; j<wc.nTerm; j++, pTerm++){
        if( pTerm->flags & (TERM_VIRTUAL|TERM_CODED) ) continue;
        if( (pTerm->prereqAll & notReady)!=0 ) continue;
        assert( pTerm->pExpr );
        sqlite3ExprIfFalse(pParse, pTerm->pExpr, cont, 1);
        pTerm->flags |= TERM_CODED;