if( idxNum & FTS3_HAVE_DOCID_GE ) pDocidGe = apVal[iIdx++];
  if( idxNum & FTS3_HAVE_DOCID_LE ) pDocidLe = apVal[iIdx++];
  assert( iIdx==nVal );

  /* In case the cursor has been used before, clear it now. */
  sqlite3_finalize(pCsr->pStmt);
  sqlite3_free(pCsr->aDoclist);

  sqlite3Fts3ExprFree(pCsr->pExpr);
  memset(&pCursor[1], 0, sizeof(Fts3Cursor)-sizeof(sqlite3_vtab_cursor));

  /* Set the lower and upper bounds on docids to return */
  pCsr->iMinDocid = fts3DocidRange(pDocidGe, SMALLEST_INT64);
  pCsr->iMaxDocid = fts3DocidRange(pDocidLe, LARGEST_INT64);

................................................................................
      for(i=0; rc==SQLITE_OK && i<p->nToken && bEof==0; i++){
        rc = incrPhraseTokenNext(pTab, p, i, &a[i], &bEof);
        if( a[i].bIgnore==0 && (bMaxSet==0 || DOCID_CMP(iMax, a[i].iDocid)<0) ){
          iMax = a[i].iDocid;
          bMaxSet = 1;
        }
      }
      assert( rc!=SQLITE_OK || a[p->nToken-1].bIgnore==0 );
      assert( rc!=SQLITE_OK || bMaxSet );

      /* Keep advancing iterators until they all point to the same document */
      for(i=0; i<p->nToken; i++){
        while( rc==SQLITE_OK && bEof==0 
            && a[i].bIgnore==0 && DOCID_CMP(a[i].iDocid, iMax)<0 
        ){

  if( idxNum & FTS3_HAVE_DOCID_GE ) pDocidGe = apVal[iIdx++];
  if( idxNum & FTS3_HAVE_DOCID_LE ) pDocidLe = apVal[iIdx++];
  assert( iIdx==nVal );

  /* In case the cursor has been used before, clear it now. */
  sqlite3_finalize(pCsr->pStmt);
  sqlite3_free(pCsr->aDoclist);
  sqlite3_free(pCsr->aMatchinfo);
  sqlite3Fts3ExprFree(pCsr->pExpr);
  memset(&pCursor[1], 0, sizeof(Fts3Cursor)-sizeof(sqlite3_vtab_cursor));

  /* Set the lower and upper bounds on docids to return */
  pCsr->iMinDocid = fts3DocidRange(pDocidGe, SMALLEST_INT64);
  pCsr->iMaxDocid = fts3DocidRange(pDocidLe, LARGEST_INT64);

................................................................................
      for(i=0; rc==SQLITE_OK && i<p->nToken && bEof==0; i++){
        rc = incrPhraseTokenNext(pTab, p, i, &a[i], &bEof);
        if( a[i].bIgnore==0 && (bMaxSet==0 || DOCID_CMP(iMax, a[i].iDocid)<0) ){
          iMax = a[i].iDocid;
          bMaxSet = 1;
        }
      }
      assert( rc!=SQLITE_OK || (p->nToken>=1 && a[p->nToken-1].bIgnore==0) );
      assert( rc!=SQLITE_OK || bMaxSet );

      /* Keep advancing iterators until they all point to the same document */
      for(i=0; i<p->nToken; i++){
        while( rc==SQLITE_OK && bEof==0 
            && a[i].bIgnore==0 && DOCID_CMP(a[i].iDocid, iMax)<0 
        ){

  sqlite3_tokenizer_cursor *pCursor;
  Fts3Expr *pRet = 0;
  int i = 0;

  /* Set variable i to the maximum number of bytes of input to tokenize. */
  for(i=0; i<n; i++){
    if( sqlite3_fts3_enable_parentheses && (z[i]=='(' || z[i]==')') ) break;
    if( z[i]=='*' || z[i]=='"' ) break;
  }

  *pnConsumed = i;
  rc = sqlite3Fts3OpenTokenizer(pTokenizer, pParse->iLangid, z, i, &pCursor);
  if( rc==SQLITE_OK ){
    const char *zToken;
    int nToken = 0, iStart = 0, iEnd = 0, iPosition = 0;

  sqlite3_tokenizer_cursor *pCursor;
  Fts3Expr *pRet = 0;
  int i = 0;

  /* Set variable i to the maximum number of bytes of input to tokenize. */
  for(i=0; i<n; i++){
    if( sqlite3_fts3_enable_parentheses && (z[i]=='(' || z[i]==')') ) break;
    if( z[i]=='"' ) break;
  }

  *pnConsumed = i;
  rc = sqlite3Fts3OpenTokenizer(pTokenizer, pParse->iLangid, z, i, &pCursor);
  if( rc==SQLITE_OK ){
    const char *zToken;
    int nToken = 0, iStart = 0, iEnd = 0, iPosition = 0;

/*
** 2014-09-21
**
** 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 SQLite extension adds a debug "authorizer" callback to the database
** connection.  The callback merely writes the authorization request to
** standard output and returns SQLITE_OK.
**
** This extension can be used (for example) in the command-line shell to
** trace the operation of the authorizer.
*/
#include "sqlite3ext.h"
SQLITE_EXTENSION_INIT1
#include <stdio.h>

/*
** Display the authorization request
*/
static int authCallback(
  void *pClientData,
  int op,
  const char *z1,
  const char *z2,
  const char *z3,
  const char *z4
){
  const char *zOp;
  char zOpSpace[50];
  switch( op ){
    case SQLITE_CREATE_INDEX:        zOp = "CREATE_INDEX";        break;
    case SQLITE_CREATE_TABLE:        zOp = "CREATE_TABLE";        break;
    case SQLITE_CREATE_TEMP_INDEX:   zOp = "CREATE_TEMP_INDEX";   break;
    case SQLITE_CREATE_TEMP_TABLE:   zOp = "CREATE_TEMP_TABLE";   break;
    case SQLITE_CREATE_TEMP_TRIGGER: zOp = "CREATE_TEMP_TRIGGER"; break;
    case SQLITE_CREATE_TEMP_VIEW:    zOp = "CREATE_TEMP_VIEW";    break;
    case SQLITE_CREATE_TRIGGER:      zOp = "CREATE_TRIGGER";      break;
    case SQLITE_CREATE_VIEW:         zOp = "CREATE_VIEW";         break;
    case SQLITE_DELETE:              zOp = "DELETE";              break;
    case SQLITE_DROP_INDEX:          zOp = "DROP_INDEX";          break;
    case SQLITE_DROP_TABLE:          zOp = "DROP_TABLE";          break;
    case SQLITE_DROP_TEMP_INDEX:     zOp = "DROP_TEMP_INDEX";     break;
    case SQLITE_DROP_TEMP_TABLE:     zOp = "DROP_TEMP_TABLE";     break;
    case SQLITE_DROP_TEMP_TRIGGER:   zOp = "DROP_TEMP_TRIGGER";   break;
    case SQLITE_DROP_TEMP_VIEW:      zOp = "DROP_TEMP_VIEW";      break;
    case SQLITE_DROP_TRIGGER:        zOp = "DROP_TRIGGER";        break;
    case SQLITE_DROP_VIEW:           zOp = "DROP_VIEW";           break;
    case SQLITE_INSERT:              zOp = "INSERT";              break;
    case SQLITE_PRAGMA:              zOp = "PRAGMA";              break;
    case SQLITE_READ:                zOp = "READ";                break;
    case SQLITE_SELECT:              zOp = "SELECT";              break;
    case SQLITE_TRANSACTION:         zOp = "TRANSACTION";         break;
    case SQLITE_UPDATE:              zOp = "UPDATE";              break;
    case SQLITE_ATTACH:              zOp = "ATTACH";              break;
    case SQLITE_DETACH:              zOp = "DETACH";              break;
    case SQLITE_ALTER_TABLE:         zOp = "ALTER_TABLE";         break;
    case SQLITE_REINDEX:             zOp = "REINDEX";             break;
    case SQLITE_ANALYZE:             zOp = "ANALYZE";             break;
    case SQLITE_CREATE_VTABLE:       zOp = "CREATE_VTABLE";       break;
    case SQLITE_DROP_VTABLE:         zOp = "DROP_VTABLE";         break;
    case SQLITE_FUNCTION:            zOp = "FUNCTION";            break;
    case SQLITE_SAVEPOINT:           zOp = "SAVEPOINT";           break;
    case SQLITE_COPY:                zOp = "COPY";                break;
    case SQLITE_RECURSIVE:           zOp = "RECURSIVE";           break;


    default: {
      sqlite3_snprintf(sizeof(zOpSpace), zOpSpace, "%d", op);
      zOp = zOpSpace;
      break;
    }
  }
  if( z1==0 ) z1 = "NULL";
  if( z2==0 ) z2 = "NULL";
  if( z3==0 ) z3 = "NULL";
  if( z4==0 ) z4 = "NULL";
  printf("AUTH: %s,%s,%s,%s,%s\n", zOp, z1, z2, z3, z4);
  return SQLITE_OK;
}



#ifdef _WIN32
__declspec(dllexport)
#endif
int sqlite3_showauth_init(
  sqlite3 *db, 
  char **pzErrMsg, 
  const sqlite3_api_routines *pApi
){
  int rc = SQLITE_OK;
  SQLITE_EXTENSION_INIT2(pApi);
  (void)pzErrMsg;  /* Unused parameter */
  rc = sqlite3_set_authorizer(db, authCallback, 0);
  return rc;
}

    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);

    /* Add the entries to the stat3 or stat4 table. */
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
    {
................................................................................
  ** 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);
  }
}

................................................................................
  int c;
  int i;
  tRowcnt v;

#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
  if( z==0 ) z = "";
#else
  if( NEVER(z==0) ) z = "";
#endif
  for(i=0; *z && i<nOut; i++){
    v = 0;
    while( (c=z[0])>='0' && c<='9' ){
      v = v*10 + c - '0';
      z++;
    }
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
    if( aOut ){
      aOut[i] = v;
    }else
#else
    assert( aOut==0 );
    UNUSED_PARAMETER(aOut);
#endif
    {
      aLog[i] = sqlite3LogEst(v);
    }

    if( *z==' ' ) z++;
  }
#ifndef SQLITE_ENABLE_STAT3_OR_STAT4
  assert( pIndex!=0 );
#else
  if( pIndex )
#endif
................................................................................
    pIndex = sqlite3PrimaryKeyIndex(pTable);
  }else{
    pIndex = sqlite3FindIndex(pInfo->db, argv[1], pInfo->zDatabase);
  }
  z = argv[2];

  if( pIndex ){









    pIndex->bUnordered = 0;
    decodeIntArray((char*)z, pIndex->nKeyCol+1, 0, pIndex->aiRowLogEst, pIndex);
    if( pIndex->pPartIdxWhere==0 ) pTable->nRowLogEst = pIndex->aiRowLogEst[0];
  }else{
    Index fakeIdx;
    fakeIdx.szIdxRow = pTable->szTabRow;
#ifdef SQLITE_ENABLE_COSTMULT
    fakeIdx.pTable = pTable;
#endif
................................................................................
      ** sample columns except the last. The last is always set to 1, as
      ** once the trailing PK fields are considered all index keys are
      ** unique.  */
      nCol = pIdx->nSampleCol-1;
      pIdx->aAvgEq[nCol] = 1;
    }
    for(iCol=0; iCol<nCol; iCol++){

      int i;                    /* Used to iterate through samples */
      tRowcnt sumEq = 0;        /* Sum of the nEq values */
      tRowcnt nSum = 0;         /* Number of terms contributing to sumEq */
      tRowcnt avgEq = 0;






      tRowcnt nDLt = pFinal->anDLt[iCol];






      /* Set nSum to the number of distinct (iCol+1) field prefixes that
      ** occur in the stat4 table for this index before pFinal. Set
      ** sumEq to the sum of the nEq values for column iCol for the same
      ** set (adding the value only once where there exist duplicate 
      ** prefixes).  */

      for(i=0; i<(pIdx->nSample-1); i++){
        if( aSample[i].anDLt[iCol]!=aSample[i+1].anDLt[iCol] ){

          sumEq += aSample[i].anEq[iCol];
          nSum++;
        }
      }
      if( nDLt>nSum ){
        avgEq = (pFinal->anLt[iCol] - sumEq)/(nDLt - nSum);



      }
      if( avgEq==0 ) avgEq = 1;
      pIdx->aAvgEq[iCol] = avgEq;
    }
  }
}

................................................................................
  /* Load the statistics from the sqlite_stat4 table. */
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
  if( rc==SQLITE_OK ){
    int lookasideEnabled = db->lookaside.bEnabled;
    db->lookaside.bEnabled = 0;
    rc = loadStat4(db, sInfo.zDatabase);
    db->lookaside.bEnabled = lookasideEnabled;





  }
#endif

  if( rc==SQLITE_NOMEM ){
    db->mallocFailed = 1;
  }
  return rc;
}


#endif /* SQLITE_OMIT_ANALYZE */

    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);
    assert( "BBB"[0]==SQLITE_AFF_TEXT );
    sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 3, regTemp, "BBB", 0);
    sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur, regNewRowid);
    sqlite3VdbeAddOp3(v, OP_Insert, iStatCur, regTemp, regNewRowid);
    sqlite3VdbeChangeP5(v, OPFLAG_APPEND);

    /* Add the entries to the stat3 or stat4 table. */
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
    {
................................................................................
  ** 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);
    assert( "BBB"[0]==SQLITE_AFF_TEXT );
    sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 3, regTemp, "BBB", 0);
    sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur, regNewRowid);
    sqlite3VdbeAddOp3(v, OP_Insert, iStatCur, regTemp, regNewRowid);
    sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
    sqlite3VdbeJumpHere(v, jZeroRows);
  }
}

................................................................................
  int c;
  int i;
  tRowcnt v;

#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
  if( z==0 ) z = "";
#else
  assert( z!=0 );
#endif
  for(i=0; *z && i<nOut; i++){
    v = 0;
    while( (c=z[0])>='0' && c<='9' ){
      v = v*10 + c - '0';
      z++;
    }
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
    if( aOut ) aOut[i] = v;
    if( aLog ) aLog[i] = sqlite3LogEst(v);

#else
    assert( aOut==0 );
    UNUSED_PARAMETER(aOut);
    assert( aLog!=0 );

    aLog[i] = sqlite3LogEst(v);

#endif
    if( *z==' ' ) z++;
  }
#ifndef SQLITE_ENABLE_STAT3_OR_STAT4
  assert( pIndex!=0 );
#else
  if( pIndex )
#endif
................................................................................
    pIndex = sqlite3PrimaryKeyIndex(pTable);
  }else{
    pIndex = sqlite3FindIndex(pInfo->db, argv[1], pInfo->zDatabase);
  }
  z = argv[2];

  if( pIndex ){
    int nCol = pIndex->nKeyCol+1;
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
    tRowcnt * const aiRowEst = pIndex->aiRowEst = (tRowcnt*)sqlite3MallocZero(
        sizeof(tRowcnt) * nCol
    );
    if( aiRowEst==0 ) pInfo->db->mallocFailed = 1;
#else
    tRowcnt * const aiRowEst = 0;
#endif
    pIndex->bUnordered = 0;
    decodeIntArray((char*)z, nCol, aiRowEst, pIndex->aiRowLogEst, pIndex);
    if( pIndex->pPartIdxWhere==0 ) pTable->nRowLogEst = pIndex->aiRowLogEst[0];
  }else{
    Index fakeIdx;
    fakeIdx.szIdxRow = pTable->szTabRow;
#ifdef SQLITE_ENABLE_COSTMULT
    fakeIdx.pTable = pTable;
#endif
................................................................................
      ** sample columns except the last. The last is always set to 1, as
      ** once the trailing PK fields are considered all index keys are
      ** unique.  */
      nCol = pIdx->nSampleCol-1;
      pIdx->aAvgEq[nCol] = 1;
    }
    for(iCol=0; iCol<nCol; iCol++){
      int nSample = pIdx->nSample;
      int i;                    /* Used to iterate through samples */
      tRowcnt sumEq = 0;        /* Sum of the nEq values */

      tRowcnt avgEq = 0;
      tRowcnt nRow;             /* Number of rows in index */
      i64 nSum100 = 0;          /* Number of terms contributing to sumEq */
      i64 nDist100;             /* Number of distinct values in index */

      if( pIdx->aiRowEst==0 || pIdx->aiRowEst[iCol+1]==0 ){
        nRow = pFinal->anLt[iCol];
        nDist100 = (i64)100 * pFinal->anDLt[iCol];
        nSample--;
      }else{
        nRow = pIdx->aiRowEst[0];
        nDist100 = ((i64)100 * pIdx->aiRowEst[0]) / pIdx->aiRowEst[iCol+1];
      }

      /* Set nSum to the number of distinct (iCol+1) field prefixes that
      ** occur in the stat4 table for this index. Set sumEq to the sum of 
      ** the nEq values for column iCol for the same set (adding the value 
      ** only once where there exist duplicate prefixes).  */

      for(i=0; i<nSample; i++){
        if( i==(pIdx->nSample-1)
         || aSample[i].anDLt[iCol]!=aSample[i+1].anDLt[iCol] 
        ){
          sumEq += aSample[i].anEq[iCol];
          nSum100 += 100;
        }
      }



      if( nDist100>nSum100 ){
        avgEq = ((i64)100 * (nRow - sumEq))/(nDist100 - nSum100);
      }
      if( avgEq==0 ) avgEq = 1;
      pIdx->aAvgEq[iCol] = avgEq;
    }
  }
}

................................................................................
  /* Load the statistics from the sqlite_stat4 table. */
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
  if( rc==SQLITE_OK ){
    int lookasideEnabled = db->lookaside.bEnabled;
    db->lookaside.bEnabled = 0;
    rc = loadStat4(db, sInfo.zDatabase);
    db->lookaside.bEnabled = lookasideEnabled;
  }
  for(i=sqliteHashFirst(&db->aDb[iDb].pSchema->idxHash);i;i=sqliteHashNext(i)){
    Index *pIdx = sqliteHashData(i);
    sqlite3_free(pIdx->aiRowEst);
    pIdx->aiRowEst = 0;
  }
#endif

  if( rc==SQLITE_NOMEM ){
    db->mallocFailed = 1;
  }
  return rc;
}


#endif /* SQLITE_OMIT_ANALYZE */

  i64 iRow,               /* The rowid that might be changing */
  int isClearTable        /* True if all rows are being deleted */
){
  BtCursor *p;
  BtShared *pBt = pBtree->pBt;
  assert( sqlite3BtreeHoldsMutex(pBtree) );
  for(p=pBt->pCursor; p; p=p->pNext){

    if( (p->curFlags & BTCF_Incrblob)!=0 && (isClearTable || p->info.nKey==iRow) ){

      p->eState = CURSOR_INVALID;
    }
  }
}

#else
  /* Stub function when INCRBLOB is omitted */
................................................................................

/* This helper routine to saveAllCursors does the actual work of saving
** the cursors if and when a cursor is found that actually requires saving.
** The common case is that no cursors need to be saved, so this routine is
** broken out from its caller to avoid unnecessary stack pointer movement.
*/
static int SQLITE_NOINLINE saveCursorsOnList(
  BtCursor *p,           /* The first cursor that needs saving */
  Pgno iRoot,            /* Only save cursor with this iRoot.  Save all if zero */
  BtCursor *pExcept      /* Do not save this cursor */
){
  do{
    if( p!=pExcept && (0==iRoot || p->pgnoRoot==iRoot) ){
      if( p->eState==CURSOR_VALID ){
        int rc = saveCursorPosition(p);
        if( SQLITE_OK!=rc ){
          return rc;
................................................................................
**
** Calling this routine with a NULL cursor pointer returns false.
**
** Use the separate sqlite3BtreeCursorRestore() routine to restore a cursor
** back to where it ought to be if this routine returns true.
*/
int sqlite3BtreeCursorHasMoved(BtCursor *pCur){
  return pCur && pCur->eState!=CURSOR_VALID;
}

/*
** This routine restores a cursor back to its original position after it
** has been moved by some outside activity (such as a btree rebalance or
** a row having been deleted out from under the cursor).  
**
................................................................................
}

/*
** Parse a cell content block and fill in the CellInfo structure.  There
** are two versions of this function.  btreeParseCell() takes a 
** cell index as the second argument and btreeParseCellPtr() 
** takes a pointer to the body of the cell as its second argument.
**
** Within this file, the parseCell() macro can be called instead of
** btreeParseCellPtr(). Using some compilers, this will be faster.
*/
static void btreeParseCellPtr(
  MemPage *pPage,         /* Page containing the cell */
  u8 *pCell,              /* Pointer to the cell text. */
  CellInfo *pInfo         /* Fill in this structure */
){
  u16 n;                  /* Number bytes in cell content header */
  u32 nPayload;           /* Number of bytes of cell payload */

  assert( sqlite3_mutex_held(pPage->pBt->mutex) );

  pInfo->pCell = pCell;
  assert( pPage->leaf==0 || pPage->leaf==1 );
  n = pPage->childPtrSize;
  assert( n==4-4*pPage->leaf );
  if( pPage->intKey ){
    if( pPage->hasData ){
      assert( n==0 );
      n = getVarint32(pCell, nPayload);
    }else{
      nPayload = 0;
    }
    n += getVarint(&pCell[n], (u64*)&pInfo->nKey);
    pInfo->nData = nPayload;
  }else{
    pInfo->nData = 0;
    n += getVarint32(&pCell[n], nPayload);
    pInfo->nKey = nPayload;
  }
  pInfo->nPayload = nPayload;
  pInfo->nHeader = n;
  testcase( nPayload==pPage->maxLocal );
  testcase( nPayload==pPage->maxLocal+1 );
  if( likely(nPayload<=pPage->maxLocal) ){
    /* This is the (easy) common case where the entire payload fits
    ** on the local page.  No overflow is required.
    */

    if( (pInfo->nSize = (u16)(n+nPayload))<4 ) pInfo->nSize = 4;
    pInfo->nLocal = (u16)nPayload;
    pInfo->iOverflow = 0;
  }else{
    /* If the payload will not fit completely on the local page, we have
    ** to decide how much to store locally and how much to spill onto
    ** overflow pages.  The strategy is to minimize the amount of unused
    ** space on overflow pages while keeping the amount of local storage
................................................................................
    testcase( surplus==maxLocal );
    testcase( surplus==maxLocal+1 );
    if( surplus <= maxLocal ){
      pInfo->nLocal = (u16)surplus;
    }else{
      pInfo->nLocal = (u16)minLocal;
    }
    pInfo->iOverflow = (u16)(pInfo->nLocal + n);
    pInfo->nSize = pInfo->iOverflow + 4;
  }
}
#define parseCell(pPage, iCell, pInfo) \
  btreeParseCellPtr((pPage), findCell((pPage), (iCell)), (pInfo))
static void btreeParseCell(
  MemPage *pPage,         /* Page containing the cell */
  int iCell,              /* The cell index.  First cell is 0 */
  CellInfo *pInfo         /* Fill in this structure */
){
  parseCell(pPage, iCell, pInfo);
}

/*
** Compute the total number of bytes that a Cell needs in the cell
** data area of the btree-page.  The return number includes the cell
** data header and the local payload, but not any overflow page or
** the space used by the cell pointer.
*/
static u16 cellSizePtr(MemPage *pPage, u8 *pCell){
  u8 *pIter = &pCell[pPage->childPtrSize];
  u32 nSize;


#ifdef SQLITE_DEBUG
  /* The value returned by this function should always be the same as
  ** the (CellInfo.nSize) value found by doing a full parse of the
  ** cell. If SQLITE_DEBUG is defined, an assert() at the bottom of
  ** this function verifies that this invariant is not violated. */
  CellInfo debuginfo;
  btreeParseCellPtr(pPage, pCell, &debuginfo);
#endif

  if( pPage->intKey ){
    u8 *pEnd;
    if( pPage->hasData ){
      pIter += getVarint32(pIter, nSize);
    }else{
      nSize = 0;
    }










    /* pIter now points at the 64-bit integer key value, a variable length 
    ** integer. The following block moves pIter to point at the first byte
    ** past the end of the key value. */
    pEnd = &pIter[9];
    while( (*pIter++)&0x80 && pIter<pEnd );
  }else{
    pIter += getVarint32(pIter, nSize);
  }

  testcase( nSize==pPage->maxLocal );
  testcase( nSize==pPage->maxLocal+1 );
  if( nSize>pPage->maxLocal ){



    int minLocal = pPage->minLocal;
    nSize = minLocal + (nSize - minLocal) % (pPage->pBt->usableSize - 4);
    testcase( nSize==pPage->maxLocal );
    testcase( nSize==pPage->maxLocal+1 );
    if( nSize>pPage->maxLocal ){
      nSize = minLocal;
    }
    nSize += 4;
  }
  nSize += (u32)(pIter - pCell);

  /* The minimum size of any cell is 4 bytes. */
  if( nSize<4 ){
    nSize = 4;
  }

  assert( nSize==debuginfo.nSize );
  return (u16)nSize;
}

#ifdef SQLITE_DEBUG
/* This variation on cellSizePtr() is used inside of assert() statements
** only. */
static u16 cellSize(MemPage *pPage, int iCell){
................................................................................
** for the overflow page.
*/
static void ptrmapPutOvflPtr(MemPage *pPage, u8 *pCell, int *pRC){
  CellInfo info;
  if( *pRC ) return;
  assert( pCell!=0 );
  btreeParseCellPtr(pPage, pCell, &info);
  assert( (info.nData+(pPage->intKey?0:info.nKey))==info.nPayload );
  if( info.iOverflow ){
    Pgno ovfl = get4byte(&pCell[info.iOverflow]);
    ptrmapPut(pPage->pBt, ovfl, PTRMAP_OVERFLOW1, pPage->pgno, pRC);
  }
}
#endif

................................................................................
** Note that even though the freeblock list was checked by btreeInitPage(),
** that routine will not detect overlap between cells or freeblocks.  Nor
** does it detect cells or freeblocks that encrouch into the reserved bytes
** at the end of the page.  So do additional corruption checks inside this
** routine and return SQLITE_CORRUPT if any problems are found.
*/
static int freeSpace(MemPage *pPage, u16 iStart, u16 iSize){
  u16 iPtr;                             /* Address of pointer to next freeblock */
  u16 iFreeBlk;                         /* Address of the next freeblock */
  u8 hdr;                               /* Page header size.  0 or 100 */
  u8 nFrag = 0;                         /* Reduction in fragmentation */
  u16 iOrigSize = iSize;                /* Original value of iSize */
  u32 iLast = pPage->pBt->usableSize-4; /* Largest possible freeblock offset */
  u32 iEnd = iStart + iSize;            /* First byte past the iStart buffer */
  unsigned char *data = pPage->aData;   /* Page content */
................................................................................
      nFrag = iFreeBlk - iEnd;
      if( iEnd>iFreeBlk ) return SQLITE_CORRUPT_BKPT;
      iEnd = iFreeBlk + get2byte(&data[iFreeBlk+2]);
      iSize = iEnd - iStart;
      iFreeBlk = get2byte(&data[iFreeBlk]);
    }
  
    /* If iPtr is another freeblock (that is, if iPtr is not the freelist pointer
    ** in the page header) then check to see if iStart should be coalesced 
    ** onto the end of iPtr.
    */
    if( iPtr>hdr+1 ){
      int iPtrEnd = iPtr + get2byte(&data[iPtr+2]);
      if( iPtrEnd+3>=iStart ){
        if( iPtrEnd>iStart ) return SQLITE_CORRUPT_BKPT;
        nFrag += iStart - iPtrEnd;
        iSize = iEnd - iPtr;
................................................................................
  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  pPage->leaf = (u8)(flagByte>>3);  assert( PTF_LEAF == 1<<3 );
  flagByte &= ~PTF_LEAF;
  pPage->childPtrSize = 4-4*pPage->leaf;
  pBt = pPage->pBt;
  if( flagByte==(PTF_LEAFDATA | PTF_INTKEY) ){
    pPage->intKey = 1;
    pPage->hasData = pPage->leaf;

    pPage->maxLocal = pBt->maxLeaf;
    pPage->minLocal = pBt->minLeaf;
  }else if( flagByte==PTF_ZERODATA ){
    pPage->intKey = 0;
    pPage->hasData = 0;

    pPage->maxLocal = pBt->maxLocal;
    pPage->minLocal = pBt->minLocal;
  }else{
    return SQLITE_CORRUPT_BKPT;
  }
  pPage->max1bytePayload = pBt->max1bytePayload;
  return SQLITE_OK;
................................................................................
#else
  return 1;
#endif
}

/*
** Make sure pBt->pTmpSpace points to an allocation of 
** MX_CELL_SIZE(pBt) bytes.

*/
static void allocateTempSpace(BtShared *pBt){
  if( !pBt->pTmpSpace ){
    pBt->pTmpSpace = sqlite3PageMalloc( pBt->pageSize );

    /* One of the uses of pBt->pTmpSpace is to format cells before
    ** inserting them into a leaf page (function fillInCell()). If
................................................................................
    ** a cell is less than 4 bytes in size, it is rounded up to 4 bytes
    ** by the various routines that manipulate binary cells. Which
    ** can mean that fillInCell() only initializes the first 2 or 3
    ** bytes of pTmpSpace, but that the first 4 bytes are copied from
    ** it into a database page. This is not actually a problem, but it
    ** does cause a valgrind error when the 1 or 2 bytes of unitialized 
    ** data is passed to system call write(). So to avoid this error,
    ** zero the first 4 bytes of temp space here.  */






    if( pBt->pTmpSpace ) memset(pBt->pTmpSpace, 0, 4);


  }
}

/*
** Free the pBt->pTmpSpace allocation
*/
static void freeTempSpace(BtShared *pBt){
  sqlite3PageFree( pBt->pTmpSpace);


  pBt->pTmpSpace = 0;

}

/*
** Close an open database and invalidate all cursors.
*/
int sqlite3BtreeClose(Btree *p){
  BtShared *pBt = p->pBt;
................................................................................
**
** If there is a transaction in progress, this routine is a no-op.
*/
static void unlockBtreeIfUnused(BtShared *pBt){
  assert( sqlite3_mutex_held(pBt->mutex) );
  assert( countValidCursors(pBt,0)==0 || pBt->inTransaction>TRANS_NONE );
  if( pBt->inTransaction==TRANS_NONE && pBt->pPage1!=0 ){

    assert( pBt->pPage1->aData );
    assert( sqlite3PagerRefcount(pBt->pPager)==1 );
    assert( pBt->pPage1->aData );
    releasePage(pBt->pPage1);
    pBt->pPage1 = 0;
  }
}

/*
** If pBt points to an empty file then convert that empty file
** into a new empty database by initializing the first page of
** the database.
................................................................................
  assert( p->inTrans>TRANS_NONE );
  assert( wrFlag==0 || p->inTrans==TRANS_WRITE );
  assert( pBt->pPage1 && pBt->pPage1->aData );

  if( NEVER(wrFlag && (pBt->btsFlags & BTS_READ_ONLY)!=0) ){
    return SQLITE_READONLY;
  }




  if( iTable==1 && btreePagecount(pBt)==0 ){
    assert( wrFlag==0 );
    iTable = 0;
  }

  /* Now that no other errors can occur, finish filling in the BtCursor
  ** variables and link the cursor into the BtShared list.  */
................................................................................
** Failure is not possible.  This function always returns SQLITE_OK.
** It might just as well be a procedure (returning void) but we continue
** to return an integer result code for historical reasons.
*/
int sqlite3BtreeDataSize(BtCursor *pCur, u32 *pSize){
  assert( cursorHoldsMutex(pCur) );
  assert( pCur->eState==CURSOR_VALID );

  getCellInfo(pCur);
  *pSize = pCur->info.nData;
  return SQLITE_OK;
}

/*
** Given the page number of an overflow page in the database (parameter
** ovfl), this function finds the page number of the next page in the 
** linked list of overflow pages. If possible, it uses the auto-vacuum
................................................................................
  u32 offset,          /* Begin reading this far into payload */
  u32 amt,             /* Read this many bytes */
  unsigned char *pBuf, /* Write the bytes into this buffer */ 
  int eOp              /* zero to read. non-zero to write. */
){
  unsigned char *aPayload;
  int rc = SQLITE_OK;
  u32 nKey;
  int iIdx = 0;
  MemPage *pPage = pCur->apPage[pCur->iPage]; /* Btree page of current entry */
  BtShared *pBt = pCur->pBt;                  /* Btree this cursor belongs to */
#ifdef SQLITE_DIRECT_OVERFLOW_READ

  int bEnd;                                   /* True if reading to end of data */
#endif

  assert( pPage );
  assert( pCur->eState==CURSOR_VALID );
  assert( pCur->aiIdx[pCur->iPage]<pPage->nCell );
  assert( cursorHoldsMutex(pCur) );
  assert( eOp!=2 || offset==0 );      /* Always start from beginning for eOp==2 */

  getCellInfo(pCur);
  aPayload = pCur->info.pCell + pCur->info.nHeader;
  nKey = (pPage->intKey ? 0 : (int)pCur->info.nKey);
#ifdef SQLITE_DIRECT_OVERFLOW_READ
  bEnd = (offset+amt==nKey+pCur->info.nData);

#endif


  if( NEVER(offset+amt > nKey+pCur->info.nData) 
   || &aPayload[pCur->info.nLocal] > &pPage->aData[pBt->usableSize]
  ){
    /* Trying to read or write past the end of the data is an error */
    return SQLITE_CORRUPT_BKPT;
  }

  /* Check if data must be read/written to/from the btree page itself. */
  if( offset<pCur->info.nLocal ){
    int a = amt;
................................................................................
      }
    }

    /* If the overflow page-list cache has been allocated and the
    ** entry for the first required overflow page is valid, skip
    ** directly to it.
    */
    if( (pCur->curFlags & BTCF_ValidOvfl)!=0 && pCur->aOverflow[offset/ovflSize] ){


      iIdx = (offset/ovflSize);
      nextPage = pCur->aOverflow[iIdx];
      offset = (offset%ovflSize);
    }

    for( ; rc==SQLITE_OK && amt>0 && nextPage; iIdx++){

................................................................................
        **
        **   1) this is a read operation, and 
        **   2) data is required from the start of this overflow page, and
        **   3) the database is file-backed, and
        **   4) there is no open write-transaction, and
        **   5) the database is not a WAL database,
        **   6) all data from the page is being read.

        **
        ** then data can be read directly from the database file into the
        ** output buffer, bypassing the page-cache altogether. This speeds
        ** up loading large records that span many overflow pages.
        */
        if( (eOp&0x01)==0                                      /* (1) */
         && offset==0                                          /* (2) */
         && (bEnd || a==ovflSize)                              /* (6) */
         && pBt->inTransaction==TRANS_READ                     /* (4) */
         && (fd = sqlite3PagerFile(pBt->pPager))->pMethods     /* (3) */
         && pBt->pPage1->aData[19]==0x01                       /* (5) */

        ){
          u8 aSave[4];
          u8 *aWrite = &pBuf[-4];

          memcpy(aSave, aWrite, 4);
          rc = sqlite3OsRead(fd, aWrite, a+4, (i64)pBt->pageSize*(nextPage-1));
          nextPage = get4byte(aWrite);
          memcpy(aWrite, aSave, 4);
        }else
#endif

................................................................................
  assert( pCur!=0 && pCur->iPage>=0 && pCur->apPage[pCur->iPage]);
  assert( pCur->eState==CURSOR_VALID );
  assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
  assert( cursorHoldsMutex(pCur) );
  assert( pCur->aiIdx[pCur->iPage]<pCur->apPage[pCur->iPage]->nCell );
  assert( pCur->info.nSize>0 );
  *pAmt = pCur->info.nLocal;
  return (void*)(pCur->info.pCell + pCur->info.nHeader);
}


/*
** For the entry that cursor pCur is point to, return as
** many bytes of the key or data as are available on the local
** b-tree page.  Write the number of available bytes into *pAmt.
................................................................................
    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;
          }
        }
        getVarint(pCell, (u64*)&nCellKey);
        if( nCellKey<intKey ){
          lwr = idx+1;
................................................................................
** 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 main entry point is sqlite3BtreePrevious().  That routine is optimized
** for the common case of merely decrementing the cell counter BtCursor.aiIdx
** to the previous cell on the current page.  The (slower) btreePrevious() helper
** routine is called when it is necessary to move to a different page or
** to restore the cursor.
**
** 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
................................................................................
  assert( cursorHoldsMutex(pCur) );
  assert( pRes!=0 );
  assert( *pRes==0 );
  assert( pCur->skipNext==0 || pCur->eState!=CURSOR_VALID );
  assert( (pCur->curFlags & (BTCF_AtLast|BTCF_ValidOvfl|BTCF_ValidNKey))==0 );
  assert( pCur->info.nSize==0 );
  if( pCur->eState!=CURSOR_VALID ){
    assert( pCur->eState>=CURSOR_REQUIRESEEK );
    rc = btreeRestoreCursorPosition(pCur);
    if( rc!=SQLITE_OK ){
      return rc;
    }
    if( CURSOR_INVALID==pCur->eState ){
      *pRes = 1;
      return SQLITE_OK;
    }
................................................................................
                 *pPgno, closest+1, k, pTrunk->pgno, n-1));
          rc = sqlite3PagerWrite(pTrunk->pDbPage);
          if( rc ) goto end_allocate_page;
          if( closest<k-1 ){
            memcpy(&aData[8+closest*4], &aData[4+k*4], 4);
          }
          put4byte(&aData[4], k-1);
          noContent = !btreeGetHasContent(pBt, *pPgno) ? PAGER_GET_NOCONTENT : 0;
          rc = btreeGetPage(pBt, *pPgno, ppPage, noContent);
          if( rc==SQLITE_OK ){
            rc = sqlite3PagerWrite((*ppPage)->pDbPage);
            if( rc!=SQLITE_OK ){
              releasePage(*ppPage);
            }
          }
................................................................................
    **
    ** Note that the pager will not actually attempt to load or journal 
    ** content for any page that really does lie past the end of the database
    ** file on disk. So the effects of disabling the no-content optimization
    ** here are confined to those pages that lie between the end of the
    ** database image and the end of the database file.
    */
    int bNoContent = (0==IfNotOmitAV(pBt->bDoTruncate)) ? PAGER_GET_NOCONTENT : 0;

    rc = sqlite3PagerWrite(pBt->pPage1->pDbPage);
    if( rc ) return rc;
    pBt->nPage++;
    if( pBt->nPage==PENDING_BYTE_PAGE(pBt) ) pBt->nPage++;

#ifndef SQLITE_OMIT_AUTOVACUUM
................................................................................
static void freePage(MemPage *pPage, int *pRC){
  if( (*pRC)==SQLITE_OK ){
    *pRC = freePage2(pPage->pBt, pPage, pPage->pgno);
  }
}

/*
** Free any overflow pages associated with the given Cell.


*/
static int clearCell(MemPage *pPage, unsigned char *pCell){




  BtShared *pBt = pPage->pBt;
  CellInfo info;
  Pgno ovflPgno;
  int rc;
  int nOvfl;
  u32 ovflPageSize;

  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  btreeParseCellPtr(pPage, pCell, &info);

  if( info.iOverflow==0 ){
    return SQLITE_OK;  /* No overflow pages. Return without doing anything */
  }
  if( pCell+info.iOverflow+3 > pPage->aData+pPage->maskPage ){
    return SQLITE_CORRUPT_BKPT;  /* Cell extends past end of page */
  }
  ovflPgno = get4byte(&pCell[info.iOverflow]);
................................................................................
  MemPage *pOvfl = 0;
  MemPage *pToRelease = 0;
  unsigned char *pPrior;
  unsigned char *pPayload;
  BtShared *pBt = pPage->pBt;
  Pgno pgnoOvfl = 0;
  int nHeader;
  CellInfo info;

  assert( sqlite3_mutex_held(pPage->pBt->mutex) );

  /* pPage is not necessarily writeable since pCell might be auxiliary
  ** buffer space that is separate from the pPage buffer area */
  assert( pCell<pPage->aData || pCell>=&pPage->aData[pBt->pageSize]
            || sqlite3PagerIswriteable(pPage->pDbPage) );

  /* Fill in the header. */
  nHeader = 0;
  if( !pPage->leaf ){
    nHeader += 4;
  }
  if( pPage->hasData ){
    nHeader += putVarint32(&pCell[nHeader], nData+nZero);
  }else{
    nData = nZero = 0;


  }
  nHeader += putVarint(&pCell[nHeader], *(u64*)&nKey);
  btreeParseCellPtr(pPage, pCell, &info);
  assert( info.nHeader==nHeader );
  assert( info.nKey==nKey );
  assert( info.nData==(u32)(nData+nZero) );
  
  /* Fill in the payload */
  nPayload = nData + nZero;
  if( pPage->intKey ){
    pSrc = pData;
    nSrc = nData;
    nData = 0;
  }else{ 
    if( NEVER(nKey>0x7fffffff || pKey==0) ){
      return SQLITE_CORRUPT_BKPT;
    }
    nPayload += (int)nKey;
    pSrc = pKey;
    nSrc = (int)nKey;
  }





  *pnSize = info.nSize;








  spaceLeft = info.nLocal;



  pPayload = &pCell[nHeader];





















  pPrior = &pCell[info.iOverflow];




  while( nPayload>0 ){
    if( spaceLeft==0 ){
#ifndef SQLITE_OMIT_AUTOVACUUM
      Pgno pgnoPtrmap = pgnoOvfl; /* Overflow page pointer-map entry page */
      if( pBt->autoVacuum ){
        do{
          pgnoOvfl++;
................................................................................
** If the cell content will fit on the page, then put it there.  If it
** will not fit, then make a copy of the cell content into pTemp if
** pTemp is not null.  Regardless of pTemp, allocate a new entry
** in pPage->apOvfl[] and make it point to the cell content (either
** in pTemp or the original pCell) and also record its index. 
** Allocating a new entry in pPage->aCell[] implies that 
** pPage->nOverflow is incremented.
**
** If nSkip is non-zero, then do not copy the first nSkip bytes of the
** cell. The caller will overwrite them after this function returns. If
** nSkip is non-zero, then pCell may not point to an invalid memory location 
** (but pCell+nSkip is always valid).
*/
static void insertCell(
  MemPage *pPage,   /* Page into which we are copying */
  int i,            /* New cell becomes the i-th cell of the page */
  u8 *pCell,        /* Content of the new cell */
  int sz,           /* Bytes of content in pCell */
  u8 *pTemp,        /* Temp storage space for pCell, if needed */
................................................................................
){
  int idx = 0;      /* Where to write new cell content in data[] */
  int j;            /* Loop counter */
  int end;          /* First byte past the last cell pointer in data[] */
  int ins;          /* Index in data[] where new cell pointer is inserted */
  int cellOffset;   /* Address of first cell pointer in data[] */
  u8 *data;         /* The content of the whole page */
  int nSkip = (iChild ? 4 : 0);

  if( *pRC ) return;

  assert( i>=0 && i<=pPage->nCell+pPage->nOverflow );
  assert( MX_CELL(pPage->pBt)<=10921 );
  assert( pPage->nCell<=MX_CELL(pPage->pBt) || CORRUPT_DB );
  assert( pPage->nOverflow<=ArraySize(pPage->apOvfl) );
................................................................................
  ** malformed cell from a leaf page to an interior page, if the cell size
  ** wanted to be less than 4 but got rounded up to 4 on the leaf, then size
  ** might be less than 8 (leaf-size + pointer) on the interior node.  Hence
  ** the term after the || in the following assert(). */
  assert( sz==cellSizePtr(pPage, pCell) || (sz==8 && iChild>0) );
  if( pPage->nOverflow || sz+2>pPage->nFree ){
    if( pTemp ){
      memcpy(pTemp+nSkip, pCell+nSkip, sz-nSkip);
      pCell = pTemp;
    }
    if( iChild ){
      put4byte(pCell, iChild);
    }
    j = pPage->nOverflow++;
    assert( j<(int)(sizeof(pPage->apOvfl)/sizeof(pPage->apOvfl[0])) );
................................................................................
    if( rc ){ *pRC = rc; return; }
    /* The allocateSpace() routine guarantees the following two properties
    ** if it returns success */
    assert( idx >= end+2 );
    assert( idx+sz <= (int)pPage->pBt->usableSize );
    pPage->nCell++;
    pPage->nFree -= (u16)(2 + sz);
    memcpy(&data[idx+nSkip], pCell+nSkip, sz-nSkip);
    if( iChild ){
      put4byte(&data[idx], iChild);
    }
    memmove(&data[ins+2], &data[ins], end-ins);
    put2byte(&data[ins], idx);
    put2byte(&data[pPage->hdrOffset+3], pPage->nCell);
#ifndef SQLITE_OMIT_AUTOVACUUM
................................................................................
  ** apCell[] include child pointers.  Either way, all cells in apCell[]
  ** are alike.
  **
  ** leafCorrection:  4 if pPage is a leaf.  0 if pPage is not a leaf.
  **       leafData:  1 if pPage holds key+data and pParent holds only keys.
  */
  leafCorrection = apOld[0]->leaf*4;
  leafData = apOld[0]->hasData;
  for(i=0; i<nOld; i++){
    int limit;
    
    /* Before doing anything else, take a copy of the i'th original sibling
    ** The rest of this function will use data from the copies rather
    ** that the original pages since the original pages will be in the
    ** process of being overwritten.  */
................................................................................
    }else{
      MemPage * const pParent = pCur->apPage[iPage-1];
      int const iIdx = pCur->aiIdx[iPage-1];

      rc = sqlite3PagerWrite(pParent->pDbPage);
      if( rc==SQLITE_OK ){
#ifndef SQLITE_OMIT_QUICKBALANCE
        if( pPage->hasData
         && pPage->nOverflow==1
         && pPage->aiOvfl[0]==pPage->nCell
         && pParent->pgno!=1
         && pParent->nCell==iIdx
        ){
          /* Call balance_quick() to create a new sibling of pPage on which
          ** to store the overflow cell. balance_quick() inserts a new cell
................................................................................

  if( pCur->eState==CURSOR_FAULT ){
    assert( pCur->skipNext!=SQLITE_OK );
    return pCur->skipNext;
  }

  assert( cursorHoldsMutex(pCur) );
  assert( (pCur->curFlags & BTCF_WriteFlag)!=0 && pBt->inTransaction==TRANS_WRITE

              && (pBt->btsFlags & BTS_READ_ONLY)==0 );
  assert( hasSharedCacheTableLock(p, pCur->pgnoRoot, pCur->pKeyInfo!=0, 2) );

  /* Assert that the caller has been consistent. If this cursor was opened
  ** expecting an index b-tree, then the caller should be inserting blob
  ** keys with no associated data. If the cursor was opened expecting an
  ** intkey table, the caller should be inserting integer keys with a
................................................................................
    /* 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->curFlags&BTCF_ValidNKey)!=0 && nKey>0 && pCur->info.nKey==nKey-1 ){

      loc = -1;
    }
  }

  if( !loc ){
    rc = btreeMoveto(pCur, pKey, nKey, appendBias, &loc);
    if( rc ) return rc;
................................................................................
  assert( pPage->intKey || nKey>=0 );
  assert( pPage->leaf || !pPage->intKey );

  TRACE(("INSERT: table=%d nkey=%lld ndata=%d page=%d %s\n",
          pCur->pgnoRoot, nKey, nData, pPage->pgno,
          loc==0 ? "overwrite" : "new entry"));
  assert( pPage->isInit );
  allocateTempSpace(pBt);
  newCell = pBt->pTmpSpace;
  if( newCell==0 ) return SQLITE_NOMEM;

  rc = fillInCell(pPage, newCell, pKey, nKey, pData, nData, nZero, &szNew);
  if( rc ) goto end_insert;
  assert( szNew==cellSizePtr(pPage, newCell) );
  assert( szNew <= MX_CELL_SIZE(pBt) );
  idx = pCur->aiIdx[pCur->iPage];
  if( loc==0 ){
    u16 szOld;
................................................................................
    if( rc ){
      goto end_insert;
    }
    oldCell = findCell(pPage, idx);
    if( !pPage->leaf ){
      memcpy(newCell, oldCell, 4);
    }
    szOld = cellSizePtr(pPage, oldCell);
    rc = clearCell(pPage, oldCell);
    dropCell(pPage, idx, szOld, &rc);
    if( rc ) goto end_insert;
  }else if( loc<0 && pPage->nCell>0 ){
    assert( pPage->leaf );
    idx = ++pCur->aiIdx[pCur->iPage];
  }else{
    assert( pPage->leaf );
................................................................................
  Btree *p = pCur->pBtree;
  BtShared *pBt = p->pBt;              
  int rc;                              /* Return code */
  MemPage *pPage;                      /* Page to delete cell from */
  unsigned char *pCell;                /* Pointer to cell to delete */
  int iCellIdx;                        /* Index of cell to delete */
  int iCellDepth;                      /* Depth of node containing pCell */ 


  assert( cursorHoldsMutex(pCur) );
  assert( pBt->inTransaction==TRANS_WRITE );
  assert( (pBt->btsFlags & BTS_READ_ONLY)==0 );
  assert( pCur->curFlags & BTCF_WriteFlag );
  assert( hasSharedCacheTableLock(p, pCur->pgnoRoot, pCur->pKeyInfo!=0, 2) );
  assert( !hasReadConflicts(p, pCur->pgnoRoot) );
................................................................................
  ** invalidate any incrblob cursors open on the row being deleted.  */
  if( pCur->pKeyInfo==0 ){
    invalidateIncrblobCursors(p, pCur->info.nKey, 0);
  }

  rc = sqlite3PagerWrite(pPage->pDbPage);
  if( rc ) return rc;
  rc = clearCell(pPage, pCell);
  dropCell(pPage, iCellIdx, cellSizePtr(pPage, pCell), &rc);
  if( rc ) return rc;

  /* If the cell deleted was not located on a leaf page, then the cursor
  ** is currently pointing to the largest entry in the sub-tree headed
  ** by the child-page of the cell that was just deleted from an internal
  ** node. The cell from the leaf node needs to be moved to the internal
  ** node to replace the deleted cell.  */
................................................................................
    int nCell;
    Pgno n = pCur->apPage[iCellDepth+1]->pgno;
    unsigned char *pTmp;

    pCell = findCell(pLeaf, pLeaf->nCell-1);
    nCell = cellSizePtr(pLeaf, pCell);
    assert( MX_CELL_SIZE(pBt) >= nCell );

    allocateTempSpace(pBt);
    pTmp = pBt->pTmpSpace;


    rc = sqlite3PagerWrite(pLeaf->pDbPage);
    insertCell(pPage, iCellIdx, pCell-4, nCell+4, pTmp, n, &rc);
    dropCell(pLeaf, pLeaf->nCell-1, nCell, &rc);
    if( rc ) return rc;
  }

  /* Balance the tree. If the entry deleted was located on a leaf page,
................................................................................
  int *pnChange            /* Add number of Cells freed to this counter */
){
  MemPage *pPage;
  int rc;
  unsigned char *pCell;
  int i;
  int hdr;


  assert( sqlite3_mutex_held(pBt->mutex) );
  if( pgno>btreePagecount(pBt) ){
    return SQLITE_CORRUPT_BKPT;
  }

  rc = getAndInitPage(pBt, pgno, &pPage, 0);
................................................................................
  hdr = pPage->hdrOffset;
  for(i=0; i<pPage->nCell; i++){
    pCell = findCell(pPage, i);
    if( !pPage->leaf ){
      rc = clearDatabasePage(pBt, get4byte(pCell), 1, pnChange);
      if( rc ) goto cleardatabasepage_out;
    }
    rc = clearCell(pPage, pCell);
    if( rc ) goto cleardatabasepage_out;
  }
  if( !pPage->leaf ){
    rc = clearDatabasePage(pBt, get4byte(&pPage->aData[hdr+8]), 1, pnChange);
    if( rc ) goto cleardatabasepage_out;
  }else if( pnChange ){
    assert( pPage->intKey );
................................................................................

#ifndef SQLITE_OMIT_INTEGRITY_CHECK
/*
** Append a message to the error message string.
*/
static void checkAppendMsg(
  IntegrityCk *pCheck,
  char *zMsg1,
  const char *zFormat,
  ...
){
  va_list ap;

  if( !pCheck->mxErr ) return;
  pCheck->mxErr--;
  pCheck->nErr++;
  va_start(ap, zFormat);
  if( pCheck->errMsg.nChar ){
    sqlite3StrAccumAppend(&pCheck->errMsg, "\n", 1);
  }
  if( zMsg1 ){

    sqlite3StrAccumAppendAll(&pCheck->errMsg, zMsg1);
  }
  sqlite3VXPrintf(&pCheck->errMsg, 1, zFormat, ap);
  va_end(ap);
  if( pCheck->errMsg.accError==STRACCUM_NOMEM ){
    pCheck->mallocFailed = 1;
  }
}
................................................................................
** Add 1 to the reference count for page iPage.  If this is the second
** reference to the page, add an error message to pCheck->zErrMsg.
** Return 1 if there are 2 or more references to the page and 0 if
** if this is the first reference to the page.
**
** Also check that the page number is in bounds.
*/
static int checkRef(IntegrityCk *pCheck, Pgno iPage, char *zContext){
  if( iPage==0 ) return 1;
  if( iPage>pCheck->nPage ){
    checkAppendMsg(pCheck, zContext, "invalid page number %d", iPage);
    return 1;
  }
  if( getPageReferenced(pCheck, iPage) ){
    checkAppendMsg(pCheck, zContext, "2nd reference to page %d", iPage);
    return 1;
  }
  setPageReferenced(pCheck, iPage);
  return 0;
}

#ifndef SQLITE_OMIT_AUTOVACUUM
................................................................................
** page iParent, pointer type ptrType. If not, append an error message
** to pCheck.
*/
static void checkPtrmap(
  IntegrityCk *pCheck,   /* Integrity check context */
  Pgno iChild,           /* Child page number */
  u8 eType,              /* Expected pointer map type */
  Pgno iParent,          /* Expected pointer map parent page number */
  char *zContext         /* Context description (used for error msg) */
){
  int rc;
  u8 ePtrmapType;
  Pgno iPtrmapParent;

  rc = ptrmapGet(pCheck->pBt, iChild, &ePtrmapType, &iPtrmapParent);
  if( rc!=SQLITE_OK ){
    if( rc==SQLITE_NOMEM || rc==SQLITE_IOERR_NOMEM ) pCheck->mallocFailed = 1;
    checkAppendMsg(pCheck, zContext, "Failed to read ptrmap key=%d", iChild);
    return;
  }

  if( ePtrmapType!=eType || iPtrmapParent!=iParent ){
    checkAppendMsg(pCheck, zContext, 
      "Bad ptr map entry key=%d expected=(%d,%d) got=(%d,%d)", 
      iChild, eType, iParent, ePtrmapType, iPtrmapParent);
  }
}
#endif

/*
................................................................................
** Check the integrity of the freelist or of an overflow page list.
** Verify that the number of pages on the list is N.
*/
static void checkList(
  IntegrityCk *pCheck,  /* Integrity checking context */
  int isFreeList,       /* True for a freelist.  False for overflow page list */
  int iPage,            /* Page number for first page in the list */
  int N,                /* Expected number of pages in the list */
  char *zContext        /* Context for error messages */
){
  int i;
  int expected = N;
  int iFirst = iPage;
  while( N-- > 0 && pCheck->mxErr ){
    DbPage *pOvflPage;
    unsigned char *pOvflData;
    if( iPage<1 ){
      checkAppendMsg(pCheck, zContext,
         "%d of %d pages missing from overflow list starting at %d",
          N+1, expected, iFirst);
      break;
    }
    if( checkRef(pCheck, iPage, zContext) ) break;
    if( sqlite3PagerGet(pCheck->pPager, (Pgno)iPage, &pOvflPage) ){
      checkAppendMsg(pCheck, zContext, "failed to get page %d", iPage);
      break;
    }
    pOvflData = (unsigned char *)sqlite3PagerGetData(pOvflPage);
    if( isFreeList ){
      int n = get4byte(&pOvflData[4]);
#ifndef SQLITE_OMIT_AUTOVACUUM
      if( pCheck->pBt->autoVacuum ){
        checkPtrmap(pCheck, iPage, PTRMAP_FREEPAGE, 0, zContext);
      }
#endif
      if( n>(int)pCheck->pBt->usableSize/4-2 ){
        checkAppendMsg(pCheck, zContext,
           "freelist leaf count too big on page %d", iPage);
        N--;
      }else{
        for(i=0; i<n; i++){
          Pgno iFreePage = get4byte(&pOvflData[8+i*4]);
#ifndef SQLITE_OMIT_AUTOVACUUM
          if( pCheck->pBt->autoVacuum ){
            checkPtrmap(pCheck, iFreePage, PTRMAP_FREEPAGE, 0, zContext);
          }
#endif
          checkRef(pCheck, iFreePage, zContext);
        }
        N -= n;
      }
    }
#ifndef SQLITE_OMIT_AUTOVACUUM
    else{
      /* If this database supports auto-vacuum and iPage is not the last
      ** page in this overflow list, check that the pointer-map entry for
      ** the following page matches iPage.
      */
      if( pCheck->pBt->autoVacuum && N>0 ){
        i = get4byte(pOvflData);
        checkPtrmap(pCheck, i, PTRMAP_OVERFLOW2, iPage, zContext);
      }
    }
#endif
    iPage = get4byte(pOvflData);
    sqlite3PagerUnref(pOvflPage);
  }
}
................................................................................
**      7.  Verify that the depth of all children is the same.
**      8.  Make sure this page is at least 33% full or else it is
**          the root of the tree.
*/
static int checkTreePage(
  IntegrityCk *pCheck,  /* Context for the sanity check */
  int iPage,            /* Page number of the page to check */
  char *zParentContext, /* Parent context */
  i64 *pnParentMinKey, 
  i64 *pnParentMaxKey
){
  MemPage *pPage;
  int i, rc, depth, d2, pgno, cnt;
  int hdr, cellStart;
  int nCell;
  u8 *data;
  BtShared *pBt;
  int usableSize;
  char zContext[100];
  char *hit = 0;
  i64 nMinKey = 0;
  i64 nMaxKey = 0;

  sqlite3_snprintf(sizeof(zContext), zContext, "Page %d: ", iPage);


  /* Check that the page exists
  */
  pBt = pCheck->pBt;
  usableSize = pBt->usableSize;
  if( iPage==0 ) return 0;
  if( checkRef(pCheck, iPage, zParentContext) ) return 0;


  if( (rc = btreeGetPage(pBt, (Pgno)iPage, &pPage, 0))!=0 ){
    checkAppendMsg(pCheck, zContext,
       "unable to get the page. error code=%d", rc);
    return 0;


  }

  /* Clear MemPage.isInit to make sure the corruption detection code in
  ** btreeInitPage() is executed.  */
  pPage->isInit = 0;
  if( (rc = btreeInitPage(pPage))!=0 ){
    assert( rc==SQLITE_CORRUPT );  /* The only possible error from InitPage */
    checkAppendMsg(pCheck, zContext, 
                   "btreeInitPage() returns error code %d", rc);
    releasePage(pPage);
    return 0;

  }

  /* Check out all the cells.
  */
  depth = 0;
  for(i=0; i<pPage->nCell && pCheck->mxErr; i++){
    u8 *pCell;
    u32 sz;
    CellInfo info;

    /* Check payload overflow pages
    */
    sqlite3_snprintf(sizeof(zContext), zContext,
             "On tree page %d cell %d: ", iPage, i);


    pCell = findCell(pPage,i);
    btreeParseCellPtr(pPage, pCell, &info);
    sz = info.nData;
    if( !pPage->intKey ) sz += (int)info.nKey;
    /* For intKey pages, check that the keys are in order.
    */


    else if( i==0 ) nMinKey = nMaxKey = info.nKey;
    else{
      if( info.nKey <= nMaxKey ){
        checkAppendMsg(pCheck, zContext, 
            "Rowid %lld out of order (previous was %lld)", info.nKey, nMaxKey);
      }
      nMaxKey = info.nKey;
    }
    assert( sz==info.nPayload );
    if( (sz>info.nLocal) 
     && (&pCell[info.iOverflow]<=&pPage->aData[pBt->usableSize])
    ){
      int nPage = (sz - info.nLocal + usableSize - 5)/(usableSize - 4);
      Pgno pgnoOvfl = get4byte(&pCell[info.iOverflow]);
#ifndef SQLITE_OMIT_AUTOVACUUM
      if( pBt->autoVacuum ){
        checkPtrmap(pCheck, pgnoOvfl, PTRMAP_OVERFLOW1, iPage, zContext);
      }
#endif
      checkList(pCheck, 0, pgnoOvfl, nPage, zContext);
    }

    /* Check sanity of left child page.
    */
    if( !pPage->leaf ){
      pgno = get4byte(pCell);
#ifndef SQLITE_OMIT_AUTOVACUUM
      if( pBt->autoVacuum ){
        checkPtrmap(pCheck, pgno, PTRMAP_BTREE, iPage, zContext);
      }
#endif
      d2 = checkTreePage(pCheck, pgno, zContext, &nMinKey, i==0 ? NULL : &nMaxKey);
      if( i>0 && d2!=depth ){
        checkAppendMsg(pCheck, zContext, "Child page depth differs");
      }
      depth = d2;
    }
  }

  if( !pPage->leaf ){
    pgno = get4byte(&pPage->aData[pPage->hdrOffset+8]);
    sqlite3_snprintf(sizeof(zContext), zContext, 
                     "On page %d at right child: ", iPage);

#ifndef SQLITE_OMIT_AUTOVACUUM
    if( pBt->autoVacuum ){
      checkPtrmap(pCheck, pgno, PTRMAP_BTREE, iPage, zContext);
    }
#endif
    checkTreePage(pCheck, pgno, zContext, NULL, !pPage->nCell ? NULL : &nMaxKey);
  }
 
  /* For intKey leaf pages, check that the min/max keys are in order
  ** with any left/parent/right pages.
  */


  if( pPage->leaf && pPage->intKey ){
    /* if we are a left child page */
    if( pnParentMinKey ){
      /* if we are the left most child page */
      if( !pnParentMaxKey ){
        if( nMaxKey > *pnParentMinKey ){
          checkAppendMsg(pCheck, zContext, 
              "Rowid %lld out of order (max larger than parent min of %lld)",
              nMaxKey, *pnParentMinKey);
        }
      }else{
        if( nMinKey <= *pnParentMinKey ){
          checkAppendMsg(pCheck, zContext, 
              "Rowid %lld out of order (min less than parent min of %lld)",
              nMinKey, *pnParentMinKey);
        }
        if( nMaxKey > *pnParentMaxKey ){
          checkAppendMsg(pCheck, zContext, 
              "Rowid %lld out of order (max larger than parent max of %lld)",
              nMaxKey, *pnParentMaxKey);
        }
        *pnParentMinKey = nMaxKey;
      }
    /* else if we're a right child page */
    } else if( pnParentMaxKey ){
      if( nMinKey <= *pnParentMaxKey ){
        checkAppendMsg(pCheck, zContext, 
            "Rowid %lld out of order (min less than parent max of %lld)",
            nMinKey, *pnParentMaxKey);
      }
    }
  }

  /* Check for complete coverage of the page
  */
  data = pPage->aData;
  hdr = pPage->hdrOffset;
  hit = sqlite3PageMalloc( pBt->pageSize );

  if( hit==0 ){
    pCheck->mallocFailed = 1;
  }else{
    int contentOffset = get2byteNotZero(&data[hdr+5]);
    assert( contentOffset<=usableSize );  /* Enforced by btreeInitPage() */
    memset(hit+contentOffset, 0, usableSize-contentOffset);
    memset(hit, 1, contentOffset);
................................................................................
      int pc = get2byte(&data[cellStart+i*2]);
      u32 size = 65536;
      int j;
      if( pc<=usableSize-4 ){
        size = cellSizePtr(pPage, &data[pc]);
      }
      if( (int)(pc+size-1)>=usableSize ){

        checkAppendMsg(pCheck, 0, 
            "Corruption detected in cell %d on page %d",i,iPage);
      }else{
        for(j=pc+size-1; j>=pc; j--) hit[j]++;
      }
    }
    i = get2byte(&data[hdr+1]);
    while( i>0 ){
................................................................................
      assert( j<=usableSize-4 );   /* Enforced by btreeInitPage() */
      i = j;
    }
    for(i=cnt=0; i<usableSize; i++){
      if( hit[i]==0 ){
        cnt++;
      }else if( hit[i]>1 ){
        checkAppendMsg(pCheck, 0,
          "Multiple uses for byte %d of page %d", i, iPage);
        break;
      }
    }
    if( cnt!=data[hdr+7] ){
      checkAppendMsg(pCheck, 0, 
          "Fragmentation of %d bytes reported as %d on page %d",
          cnt, data[hdr+7], iPage);
    }
  }
  sqlite3PageFree(hit);
  releasePage(pPage);





  return depth+1;
}
#endif /* SQLITE_OMIT_INTEGRITY_CHECK */

#ifndef SQLITE_OMIT_INTEGRITY_CHECK
/*
** This routine does a complete check of the given BTree file.  aRoot[] is
................................................................................
  nRef = sqlite3PagerRefcount(pBt->pPager);
  sCheck.pBt = pBt;
  sCheck.pPager = pBt->pPager;
  sCheck.nPage = btreePagecount(sCheck.pBt);
  sCheck.mxErr = mxErr;
  sCheck.nErr = 0;
  sCheck.mallocFailed = 0;



  *pnErr = 0;
  if( sCheck.nPage==0 ){
    sqlite3BtreeLeave(p);
    return 0;
  }

  sCheck.aPgRef = sqlite3MallocZero((sCheck.nPage / 8)+ 1);
................................................................................
  i = PENDING_BYTE_PAGE(pBt);
  if( i<=sCheck.nPage ) setPageReferenced(&sCheck, i);
  sqlite3StrAccumInit(&sCheck.errMsg, zErr, sizeof(zErr), SQLITE_MAX_LENGTH);
  sCheck.errMsg.useMalloc = 2;

  /* Check the integrity of the freelist
  */

  checkList(&sCheck, 1, get4byte(&pBt->pPage1->aData[32]),
            get4byte(&pBt->pPage1->aData[36]), "Main freelist: ");


  /* Check all the tables.
  */
  for(i=0; (int)i<nRoot && sCheck.mxErr; i++){
    if( aRoot[i]==0 ) continue;
#ifndef SQLITE_OMIT_AUTOVACUUM
    if( pBt->autoVacuum && aRoot[i]>1 ){
      checkPtrmap(&sCheck, aRoot[i], PTRMAP_ROOTPAGE, 0, 0);
    }
#endif

    checkTreePage(&sCheck, aRoot[i], "List of tree roots: ", NULL, NULL);

  }

  /* Make sure every page in the file is referenced
  */
  for(i=1; i<=sCheck.nPage && sCheck.mxErr; i++){
#ifdef SQLITE_OMIT_AUTOVACUUM
    if( getPageReferenced(&sCheck, i)==0 ){
      checkAppendMsg(&sCheck, 0, "Page %d is never used", i);
    }
#else
    /* If the database supports auto-vacuum, make sure no tables contain
    ** references to pointer-map pages.
    */
    if( getPageReferenced(&sCheck, i)==0 && 
       (PTRMAP_PAGENO(pBt, i)!=i || !pBt->autoVacuum) ){
      checkAppendMsg(&sCheck, 0, "Page %d is never used", i);
    }
    if( getPageReferenced(&sCheck, i)!=0 && 
       (PTRMAP_PAGENO(pBt, i)==i && pBt->autoVacuum) ){
      checkAppendMsg(&sCheck, 0, "Pointer map page %d is referenced", i);
    }
#endif
  }

  /* Make sure this analysis did not leave any unref() pages.
  ** This is an internal consistency check; an integrity check
  ** of the integrity check.
  */
  if( NEVER(nRef != sqlite3PagerRefcount(pBt->pPager)) ){
    checkAppendMsg(&sCheck, 0, 
      "Outstanding page count goes from %d to %d during this analysis",
      nRef, sqlite3PagerRefcount(pBt->pPager)
    );
  }

  /* Clean  up and report errors.
  */
................................................................................
    return SQLITE_ABORT;
  }

  /* Save the positions of all other cursors open on this table. This is
  ** required in case any of them are holding references to an xFetch
  ** version of the b-tree page modified by the accessPayload call below.
  **
  ** Note that pCsr must be open on a BTREE_INTKEY table and saveCursorPosition()
  ** and hence saveAllCursors() cannot fail on a BTREE_INTKEY table, hence
  ** saveAllCursors can only return SQLITE_OK.
  */
  VVA_ONLY(rc =) saveAllCursors(pCsr->pBt, pCsr->pgnoRoot, pCsr);
  assert( rc==SQLITE_OK );

  /* Check some assumptions: 

  i64 iRow,               /* The rowid that might be changing */
  int isClearTable        /* True if all rows are being deleted */
){
  BtCursor *p;
  BtShared *pBt = pBtree->pBt;
  assert( sqlite3BtreeHoldsMutex(pBtree) );
  for(p=pBt->pCursor; p; p=p->pNext){
    if( (p->curFlags & BTCF_Incrblob)!=0
     && (isClearTable || p->info.nKey==iRow)
    ){
      p->eState = CURSOR_INVALID;
    }
  }
}

#else
  /* Stub function when INCRBLOB is omitted */
................................................................................

/* This helper routine to saveAllCursors does the actual work of saving
** the cursors if and when a cursor is found that actually requires saving.
** The common case is that no cursors need to be saved, so this routine is
** broken out from its caller to avoid unnecessary stack pointer movement.
*/
static int SQLITE_NOINLINE saveCursorsOnList(
  BtCursor *p,         /* The first cursor that needs saving */
  Pgno iRoot,          /* Only save cursor with this iRoot. Save all if zero */
  BtCursor *pExcept    /* Do not save this cursor */
){
  do{
    if( p!=pExcept && (0==iRoot || p->pgnoRoot==iRoot) ){
      if( p->eState==CURSOR_VALID ){
        int rc = saveCursorPosition(p);
        if( SQLITE_OK!=rc ){
          return rc;
................................................................................
**
** Calling this routine with a NULL cursor pointer returns false.
**
** Use the separate sqlite3BtreeCursorRestore() routine to restore a cursor
** back to where it ought to be if this routine returns true.
*/
int sqlite3BtreeCursorHasMoved(BtCursor *pCur){
  return pCur->eState!=CURSOR_VALID;
}

/*
** This routine restores a cursor back to its original position after it
** has been moved by some outside activity (such as a btree rebalance or
** a row having been deleted out from under the cursor).  
**
................................................................................
}

/*
** Parse a cell content block and fill in the CellInfo structure.  There
** are two versions of this function.  btreeParseCell() takes a 
** cell index as the second argument and btreeParseCellPtr() 
** takes a pointer to the body of the cell as its second argument.



*/
static void btreeParseCellPtr(
  MemPage *pPage,         /* Page containing the cell */
  u8 *pCell,              /* Pointer to the cell text. */
  CellInfo *pInfo         /* Fill in this structure */
){
  u8 *pIter;              /* For scanning through pCell */
  u32 nPayload;           /* Number of bytes of cell payload */

  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  assert( pPage->leaf==0 || pPage->leaf==1 );
  if( pPage->intKeyLeaf ){
    assert( pPage->childPtrSize==0 );
    pIter = pCell + getVarint32(pCell, nPayload);
    pIter += getVarint(pIter, (u64*)&pInfo->nKey);
  }else if( pPage->noPayload ){
    assert( pPage->childPtrSize==4 );
    pInfo->nSize = 4 + getVarint(&pCell[4], (u64*)&pInfo->nKey);
    pInfo->nPayload = 0;
    pInfo->nLocal = 0;
    pInfo->iOverflow = 0;
    pInfo->pPayload = 0;
    return;
  }else{
    pIter = pCell + pPage->childPtrSize;
    pIter += getVarint32(pIter, nPayload);

    pInfo->nKey = nPayload;
  }
  pInfo->nPayload = nPayload;
  pInfo->pPayload = pIter;
  testcase( nPayload==pPage->maxLocal );
  testcase( nPayload==pPage->maxLocal+1 );
  if( nPayload<=pPage->maxLocal ){
    /* This is the (easy) common case where the entire payload fits
    ** on the local page.  No overflow is required.
    */
    pInfo->nSize = nPayload + (u16)(pIter - pCell);
    if( pInfo->nSize<4 ) pInfo->nSize = 4;
    pInfo->nLocal = (u16)nPayload;
    pInfo->iOverflow = 0;
  }else{
    /* If the payload will not fit completely on the local page, we have
    ** to decide how much to store locally and how much to spill onto
    ** overflow pages.  The strategy is to minimize the amount of unused
    ** space on overflow pages while keeping the amount of local storage
................................................................................
    testcase( surplus==maxLocal );
    testcase( surplus==maxLocal+1 );
    if( surplus <= maxLocal ){
      pInfo->nLocal = (u16)surplus;
    }else{
      pInfo->nLocal = (u16)minLocal;
    }
    pInfo->iOverflow = (u16)(&pInfo->pPayload[pInfo->nLocal] - pCell);
    pInfo->nSize = pInfo->iOverflow + 4;
  }
}


static void btreeParseCell(
  MemPage *pPage,         /* Page containing the cell */
  int iCell,              /* The cell index.  First cell is 0 */
  CellInfo *pInfo         /* Fill in this structure */
){
  btreeParseCellPtr(pPage, findCell(pPage, iCell), pInfo);
}

/*
** Compute the total number of bytes that a Cell needs in the cell
** data area of the btree-page.  The return number includes the cell
** data header and the local payload, but not any overflow page or
** the space used by the cell pointer.
*/
static u16 cellSizePtr(MemPage *pPage, u8 *pCell){
  u8 *pIter = pCell + pPage->childPtrSize; /* For looping over bytes of pCell */
  u8 *pEnd;                                /* End mark for a varint */
  u32 nSize;                               /* Size value to return */

#ifdef SQLITE_DEBUG
  /* The value returned by this function should always be the same as
  ** the (CellInfo.nSize) value found by doing a full parse of the
  ** cell. If SQLITE_DEBUG is defined, an assert() at the bottom of
  ** this function verifies that this invariant is not violated. */
  CellInfo debuginfo;
  btreeParseCellPtr(pPage, pCell, &debuginfo);
#endif

  if( pPage->noPayload ){
    pEnd = &pIter[9];
    while( (*pIter++)&0x80 && pIter<pEnd );
    assert( pPage->childPtrSize==4 );
    return (u16)(pIter - pCell);

  }
  nSize = *pIter;
  if( nSize>=0x80 ){
    pEnd = &pIter[9];
    nSize &= 0x7f;
    do{
      nSize = (nSize<<7) | (*++pIter & 0x7f);
    }while( *(pIter)>=0x80 && pIter<pEnd );
  }
  pIter++;
  if( pPage->intKey ){
    /* pIter now points at the 64-bit integer key value, a variable length 
    ** integer. The following block moves pIter to point at the first byte
    ** past the end of the key value. */
    pEnd = &pIter[9];
    while( (*pIter++)&0x80 && pIter<pEnd );


  }

  testcase( nSize==pPage->maxLocal );
  testcase( nSize==pPage->maxLocal+1 );
  if( nSize<=pPage->maxLocal ){
    nSize += (u32)(pIter - pCell);
    if( nSize<4 ) nSize = 4;
  }else{
    int minLocal = pPage->minLocal;
    nSize = minLocal + (nSize - minLocal) % (pPage->pBt->usableSize - 4);
    testcase( nSize==pPage->maxLocal );
    testcase( nSize==pPage->maxLocal+1 );
    if( nSize>pPage->maxLocal ){
      nSize = minLocal;
    }


    nSize += 4 + (u16)(pIter - pCell);
  }





  assert( nSize==debuginfo.nSize || CORRUPT_DB );
  return (u16)nSize;
}

#ifdef SQLITE_DEBUG
/* This variation on cellSizePtr() is used inside of assert() statements
** only. */
static u16 cellSize(MemPage *pPage, int iCell){
................................................................................
** for the overflow page.
*/
static void ptrmapPutOvflPtr(MemPage *pPage, u8 *pCell, int *pRC){
  CellInfo info;
  if( *pRC ) return;
  assert( pCell!=0 );
  btreeParseCellPtr(pPage, pCell, &info);

  if( info.iOverflow ){
    Pgno ovfl = get4byte(&pCell[info.iOverflow]);
    ptrmapPut(pPage->pBt, ovfl, PTRMAP_OVERFLOW1, pPage->pgno, pRC);
  }
}
#endif

................................................................................
** Note that even though the freeblock list was checked by btreeInitPage(),
** that routine will not detect overlap between cells or freeblocks.  Nor
** does it detect cells or freeblocks that encrouch into the reserved bytes
** at the end of the page.  So do additional corruption checks inside this
** routine and return SQLITE_CORRUPT if any problems are found.
*/
static int freeSpace(MemPage *pPage, u16 iStart, u16 iSize){
  u16 iPtr;                             /* Address of ptr to next freeblock */
  u16 iFreeBlk;                         /* Address of the next freeblock */
  u8 hdr;                               /* Page header size.  0 or 100 */
  u8 nFrag = 0;                         /* Reduction in fragmentation */
  u16 iOrigSize = iSize;                /* Original value of iSize */
  u32 iLast = pPage->pBt->usableSize-4; /* Largest possible freeblock offset */
  u32 iEnd = iStart + iSize;            /* First byte past the iStart buffer */
  unsigned char *data = pPage->aData;   /* Page content */
................................................................................
      nFrag = iFreeBlk - iEnd;
      if( iEnd>iFreeBlk ) return SQLITE_CORRUPT_BKPT;
      iEnd = iFreeBlk + get2byte(&data[iFreeBlk+2]);
      iSize = iEnd - iStart;
      iFreeBlk = get2byte(&data[iFreeBlk]);
    }
  
    /* If iPtr is another freeblock (that is, if iPtr is not the freelist
    ** pointer in the page header) then check to see if iStart should be
    ** coalesced onto the end of iPtr.
    */
    if( iPtr>hdr+1 ){
      int iPtrEnd = iPtr + get2byte(&data[iPtr+2]);
      if( iPtrEnd+3>=iStart ){
        if( iPtrEnd>iStart ) return SQLITE_CORRUPT_BKPT;
        nFrag += iStart - iPtrEnd;
        iSize = iEnd - iPtr;
................................................................................
  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  pPage->leaf = (u8)(flagByte>>3);  assert( PTF_LEAF == 1<<3 );
  flagByte &= ~PTF_LEAF;
  pPage->childPtrSize = 4-4*pPage->leaf;
  pBt = pPage->pBt;
  if( flagByte==(PTF_LEAFDATA | PTF_INTKEY) ){
    pPage->intKey = 1;
    pPage->intKeyLeaf = pPage->leaf;
    pPage->noPayload = !pPage->leaf;
    pPage->maxLocal = pBt->maxLeaf;
    pPage->minLocal = pBt->minLeaf;
  }else if( flagByte==PTF_ZERODATA ){
    pPage->intKey = 0;
    pPage->intKeyLeaf = 0;
    pPage->noPayload = 0;
    pPage->maxLocal = pBt->maxLocal;
    pPage->minLocal = pBt->minLocal;
  }else{
    return SQLITE_CORRUPT_BKPT;
  }
  pPage->max1bytePayload = pBt->max1bytePayload;
  return SQLITE_OK;
................................................................................
#else
  return 1;
#endif
}

/*
** Make sure pBt->pTmpSpace points to an allocation of 
** MX_CELL_SIZE(pBt) bytes with a 4-byte prefix for a left-child
** pointer.
*/
static void allocateTempSpace(BtShared *pBt){
  if( !pBt->pTmpSpace ){
    pBt->pTmpSpace = sqlite3PageMalloc( pBt->pageSize );

    /* One of the uses of pBt->pTmpSpace is to format cells before
    ** inserting them into a leaf page (function fillInCell()). If
................................................................................
    ** a cell is less than 4 bytes in size, it is rounded up to 4 bytes
    ** by the various routines that manipulate binary cells. Which
    ** can mean that fillInCell() only initializes the first 2 or 3
    ** bytes of pTmpSpace, but that the first 4 bytes are copied from
    ** it into a database page. This is not actually a problem, but it
    ** does cause a valgrind error when the 1 or 2 bytes of unitialized 
    ** data is passed to system call write(). So to avoid this error,
    ** zero the first 4 bytes of temp space here.
    **
    ** Also:  Provide four bytes of initialized space before the
    ** beginning of pTmpSpace as an area available to prepend the
    ** left-child pointer to the beginning of a cell.
    */
    if( pBt->pTmpSpace ){
      memset(pBt->pTmpSpace, 0, 8);
      pBt->pTmpSpace += 4;
    }
  }
}

/*
** Free the pBt->pTmpSpace allocation
*/
static void freeTempSpace(BtShared *pBt){
  if( pBt->pTmpSpace ){
    pBt->pTmpSpace -= 4;
    sqlite3PageFree(pBt->pTmpSpace);
    pBt->pTmpSpace = 0;
  }
}

/*
** Close an open database and invalidate all cursors.
*/
int sqlite3BtreeClose(Btree *p){
  BtShared *pBt = p->pBt;
................................................................................
**
** If there is a transaction in progress, this routine is a no-op.
*/
static void unlockBtreeIfUnused(BtShared *pBt){
  assert( sqlite3_mutex_held(pBt->mutex) );
  assert( countValidCursors(pBt,0)==0 || pBt->inTransaction>TRANS_NONE );
  if( pBt->inTransaction==TRANS_NONE && pBt->pPage1!=0 ){
    MemPage *pPage1 = pBt->pPage1;
    assert( pPage1->aData );
    assert( sqlite3PagerRefcount(pBt->pPager)==1 );
    pBt->pPage1 = 0;
    releasePage(pPage1);

  }
}

/*
** If pBt points to an empty file then convert that empty file
** into a new empty database by initializing the first page of
** the database.
................................................................................
  assert( p->inTrans>TRANS_NONE );
  assert( wrFlag==0 || p->inTrans==TRANS_WRITE );
  assert( pBt->pPage1 && pBt->pPage1->aData );

  if( NEVER(wrFlag && (pBt->btsFlags & BTS_READ_ONLY)!=0) ){
    return SQLITE_READONLY;
  }
  if( wrFlag ){
    allocateTempSpace(pBt);
    if( pBt->pTmpSpace==0 ) return SQLITE_NOMEM;
  }
  if( iTable==1 && btreePagecount(pBt)==0 ){
    assert( wrFlag==0 );
    iTable = 0;
  }

  /* Now that no other errors can occur, finish filling in the BtCursor
  ** variables and link the cursor into the BtShared list.  */
................................................................................
** Failure is not possible.  This function always returns SQLITE_OK.
** It might just as well be a procedure (returning void) but we continue
** to return an integer result code for historical reasons.
*/
int sqlite3BtreeDataSize(BtCursor *pCur, u32 *pSize){
  assert( cursorHoldsMutex(pCur) );
  assert( pCur->eState==CURSOR_VALID );
  assert( pCur->apPage[pCur->iPage]->intKeyLeaf==1 );
  getCellInfo(pCur);
  *pSize = pCur->info.nPayload;
  return SQLITE_OK;
}

/*
** Given the page number of an overflow page in the database (parameter
** ovfl), this function finds the page number of the next page in the 
** linked list of overflow pages. If possible, it uses the auto-vacuum
................................................................................
  u32 offset,          /* Begin reading this far into payload */
  u32 amt,             /* Read this many bytes */
  unsigned char *pBuf, /* Write the bytes into this buffer */ 
  int eOp              /* zero to read. non-zero to write. */
){
  unsigned char *aPayload;
  int rc = SQLITE_OK;

  int iIdx = 0;
  MemPage *pPage = pCur->apPage[pCur->iPage]; /* Btree page of current entry */
  BtShared *pBt = pCur->pBt;                  /* Btree this cursor belongs to */
#ifdef SQLITE_DIRECT_OVERFLOW_READ
  unsigned char * const pBufStart = pBuf;
  int bEnd;                                 /* True if reading to end of data */
#endif

  assert( pPage );
  assert( pCur->eState==CURSOR_VALID );
  assert( pCur->aiIdx[pCur->iPage]<pPage->nCell );
  assert( cursorHoldsMutex(pCur) );
  assert( eOp!=2 || offset==0 );    /* Always start from beginning for eOp==2 */

  getCellInfo(pCur);
  aPayload = pCur->info.pPayload;

#ifdef SQLITE_DIRECT_OVERFLOW_READ

  bEnd = offset+amt==pCur->info.nPayload;
#endif
  assert( offset+amt <= pCur->info.nPayload );


  if( &aPayload[pCur->info.nLocal] > &pPage->aData[pBt->usableSize] ){

    /* Trying to read or write past the end of the data is an error */
    return SQLITE_CORRUPT_BKPT;
  }

  /* Check if data must be read/written to/from the btree page itself. */
  if( offset<pCur->info.nLocal ){
    int a = amt;
................................................................................
      }
    }

    /* If the overflow page-list cache has been allocated and the
    ** entry for the first required overflow page is valid, skip
    ** directly to it.
    */
    if( (pCur->curFlags & BTCF_ValidOvfl)!=0
     && pCur->aOverflow[offset/ovflSize]
    ){
      iIdx = (offset/ovflSize);
      nextPage = pCur->aOverflow[iIdx];
      offset = (offset%ovflSize);
    }

    for( ; rc==SQLITE_OK && amt>0 && nextPage; iIdx++){

................................................................................
        **
        **   1) this is a read operation, and 
        **   2) data is required from the start of this overflow page, and
        **   3) the database is file-backed, and
        **   4) there is no open write-transaction, and
        **   5) the database is not a WAL database,
        **   6) all data from the page is being read.
        **   7) at least 4 bytes have already been read into the output buffer 
        **
        ** then data can be read directly from the database file into the
        ** output buffer, bypassing the page-cache altogether. This speeds
        ** up loading large records that span many overflow pages.
        */
        if( (eOp&0x01)==0                                      /* (1) */
         && offset==0                                          /* (2) */
         && (bEnd || a==ovflSize)                              /* (6) */
         && pBt->inTransaction==TRANS_READ                     /* (4) */
         && (fd = sqlite3PagerFile(pBt->pPager))->pMethods     /* (3) */
         && pBt->pPage1->aData[19]==0x01                       /* (5) */
         && &pBuf[-4]>=pBufStart                               /* (7) */
        ){
          u8 aSave[4];
          u8 *aWrite = &pBuf[-4];
          assert( aWrite>=pBufStart );                         /* hence (7) */
          memcpy(aSave, aWrite, 4);
          rc = sqlite3OsRead(fd, aWrite, a+4, (i64)pBt->pageSize*(nextPage-1));
          nextPage = get4byte(aWrite);
          memcpy(aWrite, aSave, 4);
        }else
#endif

................................................................................
  assert( pCur!=0 && pCur->iPage>=0 && pCur->apPage[pCur->iPage]);
  assert( pCur->eState==CURSOR_VALID );
  assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
  assert( cursorHoldsMutex(pCur) );
  assert( pCur->aiIdx[pCur->iPage]<pCur->apPage[pCur->iPage]->nCell );
  assert( pCur->info.nSize>0 );
  *pAmt = pCur->info.nLocal;
  return (void*)pCur->info.pPayload;
}


/*
** For the entry that cursor pCur is point to, return as
** many bytes of the key or data as are available on the local
** b-tree page.  Write the number of available bytes into *pAmt.
................................................................................
    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->intKeyLeaf ){
          while( 0x80 <= *(pCell++) ){
            if( pCell>=pPage->aDataEnd ) return SQLITE_CORRUPT_BKPT;
          }
        }
        getVarint(pCell, (u64*)&nCellKey);
        if( nCellKey<intKey ){
          lwr = idx+1;
................................................................................
** 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 main entry point is sqlite3BtreePrevious().  That routine is optimized
** for the common case of merely decrementing the cell counter BtCursor.aiIdx
** to the previous cell on the current page.  The (slower) btreePrevious()
** helper routine is called when it is necessary to move to a different page
** or to restore the cursor.
**
** 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
................................................................................
  assert( cursorHoldsMutex(pCur) );
  assert( pRes!=0 );
  assert( *pRes==0 );
  assert( pCur->skipNext==0 || pCur->eState!=CURSOR_VALID );
  assert( (pCur->curFlags & (BTCF_AtLast|BTCF_ValidOvfl|BTCF_ValidNKey))==0 );
  assert( pCur->info.nSize==0 );
  if( pCur->eState!=CURSOR_VALID ){

    rc = restoreCursorPosition(pCur);
    if( rc!=SQLITE_OK ){
      return rc;
    }
    if( CURSOR_INVALID==pCur->eState ){
      *pRes = 1;
      return SQLITE_OK;
    }
................................................................................
                 *pPgno, closest+1, k, pTrunk->pgno, n-1));
          rc = sqlite3PagerWrite(pTrunk->pDbPage);
          if( rc ) goto end_allocate_page;
          if( closest<k-1 ){
            memcpy(&aData[8+closest*4], &aData[4+k*4], 4);
          }
          put4byte(&aData[4], k-1);
          noContent = !btreeGetHasContent(pBt, *pPgno)? PAGER_GET_NOCONTENT : 0;
          rc = btreeGetPage(pBt, *pPgno, ppPage, noContent);
          if( rc==SQLITE_OK ){
            rc = sqlite3PagerWrite((*ppPage)->pDbPage);
            if( rc!=SQLITE_OK ){
              releasePage(*ppPage);
            }
          }
................................................................................
    **
    ** Note that the pager will not actually attempt to load or journal 
    ** content for any page that really does lie past the end of the database
    ** file on disk. So the effects of disabling the no-content optimization
    ** here are confined to those pages that lie between the end of the
    ** database image and the end of the database file.
    */
    int bNoContent = (0==IfNotOmitAV(pBt->bDoTruncate))? PAGER_GET_NOCONTENT:0;

    rc = sqlite3PagerWrite(pBt->pPage1->pDbPage);
    if( rc ) return rc;
    pBt->nPage++;
    if( pBt->nPage==PENDING_BYTE_PAGE(pBt) ) pBt->nPage++;

#ifndef SQLITE_OMIT_AUTOVACUUM
................................................................................
static void freePage(MemPage *pPage, int *pRC){
  if( (*pRC)==SQLITE_OK ){
    *pRC = freePage2(pPage->pBt, pPage, pPage->pgno);
  }
}

/*
** Free any overflow pages associated with the given Cell.  Write the
** local Cell size (the number of bytes on the original page, omitting
** overflow) into *pnSize.
*/
static int clearCell(
  MemPage *pPage,          /* The page that contains the Cell */
  unsigned char *pCell,    /* First byte of the Cell */
  u16 *pnSize              /* Write the size of the Cell here */
){
  BtShared *pBt = pPage->pBt;
  CellInfo info;
  Pgno ovflPgno;
  int rc;
  int nOvfl;
  u32 ovflPageSize;

  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  btreeParseCellPtr(pPage, pCell, &info);
  *pnSize = info.nSize;
  if( info.iOverflow==0 ){
    return SQLITE_OK;  /* No overflow pages. Return without doing anything */
  }
  if( pCell+info.iOverflow+3 > pPage->aData+pPage->maskPage ){
    return SQLITE_CORRUPT_BKPT;  /* Cell extends past end of page */
  }
  ovflPgno = get4byte(&pCell[info.iOverflow]);
................................................................................
  MemPage *pOvfl = 0;
  MemPage *pToRelease = 0;
  unsigned char *pPrior;
  unsigned char *pPayload;
  BtShared *pBt = pPage->pBt;
  Pgno pgnoOvfl = 0;
  int nHeader;


  assert( sqlite3_mutex_held(pPage->pBt->mutex) );

  /* pPage is not necessarily writeable since pCell might be auxiliary
  ** buffer space that is separate from the pPage buffer area */
  assert( pCell<pPage->aData || pCell>=&pPage->aData[pBt->pageSize]
            || sqlite3PagerIswriteable(pPage->pDbPage) );

  /* Fill in the header. */
  nHeader = pPage->childPtrSize;
  nPayload = nData + nZero;


  if( pPage->intKeyLeaf ){
    nHeader += putVarint32(&pCell[nHeader], nPayload);
  }else{

    assert( nData==0 );
    assert( nZero==0 );
  }
  nHeader += putVarint(&pCell[nHeader], *(u64*)&nKey);




  
  /* Fill in the payload size */

  if( pPage->intKey ){
    pSrc = pData;
    nSrc = nData;
    nData = 0;
  }else{ 
    if( NEVER(nKey>0x7fffffff || pKey==0) ){
      return SQLITE_CORRUPT_BKPT;
    }
    nPayload = (int)nKey;
    pSrc = pKey;
    nSrc = (int)nKey;
  }
  if( nPayload<=pPage->maxLocal ){
    n = nHeader + nPayload;
    testcase( n==3 );
    testcase( n==4 );
    if( n<4 ) n = 4;
    *pnSize = n;
    spaceLeft = nPayload;
    pPrior = pCell;
  }else{
    int mn = pPage->minLocal;
    n = mn + (nPayload - mn) % (pPage->pBt->usableSize - 4);
    testcase( n==pPage->maxLocal );
    testcase( n==pPage->maxLocal+1 );
    if( n > pPage->maxLocal ) n = mn;
    spaceLeft = n;
    *pnSize = n + nHeader + 4;
    pPrior = &pCell[nHeader+n];
  }
  pPayload = &pCell[nHeader];

  /* At this point variables should be set as follows:
  **
  **   nPayload           Total payload size in bytes
  **   pPayload           Begin writing payload here
  **   spaceLeft          Space available at pPayload.  If nPayload>spaceLeft,
  **                      that means content must spill into overflow pages.
  **   *pnSize            Size of the local cell (not counting overflow pages)
  **   pPrior             Where to write the pgno of the first overflow page
  **
  ** Use a call to btreeParseCellPtr() to verify that the values above
  ** were computed correctly.
  */
#if SQLITE_DEBUG
  {
    CellInfo info;
    btreeParseCellPtr(pPage, pCell, &info);
    assert( nHeader=(int)(info.pPayload - pCell) );
    assert( info.nKey==nKey );
    assert( *pnSize == info.nSize );
    assert( spaceLeft == info.nLocal );
    assert( pPrior == &pCell[info.iOverflow] );
  }
#endif

  /* Write the payload into the local Cell and any extra into overflow pages */
  while( nPayload>0 ){
    if( spaceLeft==0 ){
#ifndef SQLITE_OMIT_AUTOVACUUM
      Pgno pgnoPtrmap = pgnoOvfl; /* Overflow page pointer-map entry page */
      if( pBt->autoVacuum ){
        do{
          pgnoOvfl++;
................................................................................
** If the cell content will fit on the page, then put it there.  If it
** will not fit, then make a copy of the cell content into pTemp if
** pTemp is not null.  Regardless of pTemp, allocate a new entry
** in pPage->apOvfl[] and make it point to the cell content (either
** in pTemp or the original pCell) and also record its index. 
** Allocating a new entry in pPage->aCell[] implies that 
** pPage->nOverflow is incremented.





*/
static void insertCell(
  MemPage *pPage,   /* Page into which we are copying */
  int i,            /* New cell becomes the i-th cell of the page */
  u8 *pCell,        /* Content of the new cell */
  int sz,           /* Bytes of content in pCell */
  u8 *pTemp,        /* Temp storage space for pCell, if needed */
................................................................................
){
  int idx = 0;      /* Where to write new cell content in data[] */
  int j;            /* Loop counter */
  int end;          /* First byte past the last cell pointer in data[] */
  int ins;          /* Index in data[] where new cell pointer is inserted */
  int cellOffset;   /* Address of first cell pointer in data[] */
  u8 *data;         /* The content of the whole page */


  if( *pRC ) return;

  assert( i>=0 && i<=pPage->nCell+pPage->nOverflow );
  assert( MX_CELL(pPage->pBt)<=10921 );
  assert( pPage->nCell<=MX_CELL(pPage->pBt) || CORRUPT_DB );
  assert( pPage->nOverflow<=ArraySize(pPage->apOvfl) );
................................................................................
  ** malformed cell from a leaf page to an interior page, if the cell size
  ** wanted to be less than 4 but got rounded up to 4 on the leaf, then size
  ** might be less than 8 (leaf-size + pointer) on the interior node.  Hence
  ** the term after the || in the following assert(). */
  assert( sz==cellSizePtr(pPage, pCell) || (sz==8 && iChild>0) );
  if( pPage->nOverflow || sz+2>pPage->nFree ){
    if( pTemp ){
      memcpy(pTemp, pCell, sz);
      pCell = pTemp;
    }
    if( iChild ){
      put4byte(pCell, iChild);
    }
    j = pPage->nOverflow++;
    assert( j<(int)(sizeof(pPage->apOvfl)/sizeof(pPage->apOvfl[0])) );
................................................................................
    if( rc ){ *pRC = rc; return; }
    /* The allocateSpace() routine guarantees the following two properties
    ** if it returns success */
    assert( idx >= end+2 );
    assert( idx+sz <= (int)pPage->pBt->usableSize );
    pPage->nCell++;
    pPage->nFree -= (u16)(2 + sz);
    memcpy(&data[idx], pCell, sz);
    if( iChild ){
      put4byte(&data[idx], iChild);
    }
    memmove(&data[ins+2], &data[ins], end-ins);
    put2byte(&data[ins], idx);
    put2byte(&data[pPage->hdrOffset+3], pPage->nCell);
#ifndef SQLITE_OMIT_AUTOVACUUM
................................................................................
  ** apCell[] include child pointers.  Either way, all cells in apCell[]
  ** are alike.
  **
  ** leafCorrection:  4 if pPage is a leaf.  0 if pPage is not a leaf.
  **       leafData:  1 if pPage holds key+data and pParent holds only keys.
  */
  leafCorrection = apOld[0]->leaf*4;
  leafData = apOld[0]->intKeyLeaf;
  for(i=0; i<nOld; i++){
    int limit;
    
    /* Before doing anything else, take a copy of the i'th original sibling
    ** The rest of this function will use data from the copies rather
    ** that the original pages since the original pages will be in the
    ** process of being overwritten.  */
................................................................................
    }else{
      MemPage * const pParent = pCur->apPage[iPage-1];
      int const iIdx = pCur->aiIdx[iPage-1];

      rc = sqlite3PagerWrite(pParent->pDbPage);
      if( rc==SQLITE_OK ){
#ifndef SQLITE_OMIT_QUICKBALANCE
        if( pPage->intKeyLeaf
         && pPage->nOverflow==1
         && pPage->aiOvfl[0]==pPage->nCell
         && pParent->pgno!=1
         && pParent->nCell==iIdx
        ){
          /* Call balance_quick() to create a new sibling of pPage on which
          ** to store the overflow cell. balance_quick() inserts a new cell
................................................................................

  if( pCur->eState==CURSOR_FAULT ){
    assert( pCur->skipNext!=SQLITE_OK );
    return pCur->skipNext;
  }

  assert( cursorHoldsMutex(pCur) );
  assert( (pCur->curFlags & BTCF_WriteFlag)!=0
              && pBt->inTransaction==TRANS_WRITE
              && (pBt->btsFlags & BTS_READ_ONLY)==0 );
  assert( hasSharedCacheTableLock(p, pCur->pgnoRoot, pCur->pKeyInfo!=0, 2) );

  /* Assert that the caller has been consistent. If this cursor was opened
  ** expecting an index b-tree, then the caller should be inserting blob
  ** keys with no associated data. If the cursor was opened expecting an
  ** intkey table, the caller should be inserting integer keys with a
................................................................................
    /* 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->curFlags&BTCF_ValidNKey)!=0 && nKey>0
      && pCur->info.nKey==nKey-1 ){
      loc = -1;
    }
  }

  if( !loc ){
    rc = btreeMoveto(pCur, pKey, nKey, appendBias, &loc);
    if( rc ) return rc;
................................................................................
  assert( pPage->intKey || nKey>=0 );
  assert( pPage->leaf || !pPage->intKey );

  TRACE(("INSERT: table=%d nkey=%lld ndata=%d page=%d %s\n",
          pCur->pgnoRoot, nKey, nData, pPage->pgno,
          loc==0 ? "overwrite" : "new entry"));
  assert( pPage->isInit );

  newCell = pBt->pTmpSpace;

  assert( newCell!=0 );
  rc = fillInCell(pPage, newCell, pKey, nKey, pData, nData, nZero, &szNew);
  if( rc ) goto end_insert;
  assert( szNew==cellSizePtr(pPage, newCell) );
  assert( szNew <= MX_CELL_SIZE(pBt) );
  idx = pCur->aiIdx[pCur->iPage];
  if( loc==0 ){
    u16 szOld;
................................................................................
    if( rc ){
      goto end_insert;
    }
    oldCell = findCell(pPage, idx);
    if( !pPage->leaf ){
      memcpy(newCell, oldCell, 4);
    }

    rc = clearCell(pPage, oldCell, &szOld);
    dropCell(pPage, idx, szOld, &rc);
    if( rc ) goto end_insert;
  }else if( loc<0 && pPage->nCell>0 ){
    assert( pPage->leaf );
    idx = ++pCur->aiIdx[pCur->iPage];
  }else{
    assert( pPage->leaf );
................................................................................
  Btree *p = pCur->pBtree;
  BtShared *pBt = p->pBt;              
  int rc;                              /* Return code */
  MemPage *pPage;                      /* Page to delete cell from */
  unsigned char *pCell;                /* Pointer to cell to delete */
  int iCellIdx;                        /* Index of cell to delete */
  int iCellDepth;                      /* Depth of node containing pCell */ 
  u16 szCell;                          /* Size of the cell being deleted */

  assert( cursorHoldsMutex(pCur) );
  assert( pBt->inTransaction==TRANS_WRITE );
  assert( (pBt->btsFlags & BTS_READ_ONLY)==0 );
  assert( pCur->curFlags & BTCF_WriteFlag );
  assert( hasSharedCacheTableLock(p, pCur->pgnoRoot, pCur->pKeyInfo!=0, 2) );
  assert( !hasReadConflicts(p, pCur->pgnoRoot) );
................................................................................
  ** invalidate any incrblob cursors open on the row being deleted.  */
  if( pCur->pKeyInfo==0 ){
    invalidateIncrblobCursors(p, pCur->info.nKey, 0);
  }

  rc = sqlite3PagerWrite(pPage->pDbPage);
  if( rc ) return rc;
  rc = clearCell(pPage, pCell, &szCell);
  dropCell(pPage, iCellIdx, szCell, &rc);
  if( rc ) return rc;

  /* If the cell deleted was not located on a leaf page, then the cursor
  ** is currently pointing to the largest entry in the sub-tree headed
  ** by the child-page of the cell that was just deleted from an internal
  ** node. The cell from the leaf node needs to be moved to the internal
  ** node to replace the deleted cell.  */
................................................................................
    int nCell;
    Pgno n = pCur->apPage[iCellDepth+1]->pgno;
    unsigned char *pTmp;

    pCell = findCell(pLeaf, pLeaf->nCell-1);
    nCell = cellSizePtr(pLeaf, pCell);
    assert( MX_CELL_SIZE(pBt) >= nCell );


    pTmp = pBt->pTmpSpace;

    assert( pTmp!=0 );
    rc = sqlite3PagerWrite(pLeaf->pDbPage);
    insertCell(pPage, iCellIdx, pCell-4, nCell+4, pTmp, n, &rc);
    dropCell(pLeaf, pLeaf->nCell-1, nCell, &rc);
    if( rc ) return rc;
  }

  /* Balance the tree. If the entry deleted was located on a leaf page,
................................................................................
  int *pnChange            /* Add number of Cells freed to this counter */
){
  MemPage *pPage;
  int rc;
  unsigned char *pCell;
  int i;
  int hdr;
  u16 szCell;

  assert( sqlite3_mutex_held(pBt->mutex) );
  if( pgno>btreePagecount(pBt) ){
    return SQLITE_CORRUPT_BKPT;
  }

  rc = getAndInitPage(pBt, pgno, &pPage, 0);
................................................................................
  hdr = pPage->hdrOffset;
  for(i=0; i<pPage->nCell; i++){
    pCell = findCell(pPage, i);
    if( !pPage->leaf ){
      rc = clearDatabasePage(pBt, get4byte(pCell), 1, pnChange);
      if( rc ) goto cleardatabasepage_out;
    }
    rc = clearCell(pPage, pCell, &szCell);
    if( rc ) goto cleardatabasepage_out;
  }
  if( !pPage->leaf ){
    rc = clearDatabasePage(pBt, get4byte(&pPage->aData[hdr+8]), 1, pnChange);
    if( rc ) goto cleardatabasepage_out;
  }else if( pnChange ){
    assert( pPage->intKey );
................................................................................

#ifndef SQLITE_OMIT_INTEGRITY_CHECK
/*
** Append a message to the error message string.
*/
static void checkAppendMsg(
  IntegrityCk *pCheck,

  const char *zFormat,
  ...
){
  va_list ap;
  char zBuf[200];
  if( !pCheck->mxErr ) return;
  pCheck->mxErr--;
  pCheck->nErr++;
  va_start(ap, zFormat);
  if( pCheck->errMsg.nChar ){
    sqlite3StrAccumAppend(&pCheck->errMsg, "\n", 1);
  }
  if( pCheck->zPfx ){
    sqlite3_snprintf(sizeof(zBuf), zBuf, pCheck->zPfx, pCheck->v1, pCheck->v2);
    sqlite3StrAccumAppendAll(&pCheck->errMsg, zBuf);
  }
  sqlite3VXPrintf(&pCheck->errMsg, 1, zFormat, ap);
  va_end(ap);
  if( pCheck->errMsg.accError==STRACCUM_NOMEM ){
    pCheck->mallocFailed = 1;
  }
}
................................................................................
** Add 1 to the reference count for page iPage.  If this is the second
** reference to the page, add an error message to pCheck->zErrMsg.
** Return 1 if there are 2 or more references to the page and 0 if
** if this is the first reference to the page.
**
** Also check that the page number is in bounds.
*/
static int checkRef(IntegrityCk *pCheck, Pgno iPage){
  if( iPage==0 ) return 1;
  if( iPage>pCheck->nPage ){
    checkAppendMsg(pCheck, "invalid page number %d", iPage);
    return 1;
  }
  if( getPageReferenced(pCheck, iPage) ){
    checkAppendMsg(pCheck, "2nd reference to page %d", iPage);
    return 1;
  }
  setPageReferenced(pCheck, iPage);
  return 0;
}

#ifndef SQLITE_OMIT_AUTOVACUUM
................................................................................
** page iParent, pointer type ptrType. If not, append an error message
** to pCheck.
*/
static void checkPtrmap(
  IntegrityCk *pCheck,   /* Integrity check context */
  Pgno iChild,           /* Child page number */
  u8 eType,              /* Expected pointer map type */
  Pgno iParent           /* Expected pointer map parent page number */

){
  int rc;
  u8 ePtrmapType;
  Pgno iPtrmapParent;

  rc = ptrmapGet(pCheck->pBt, iChild, &ePtrmapType, &iPtrmapParent);
  if( rc!=SQLITE_OK ){
    if( rc==SQLITE_NOMEM || rc==SQLITE_IOERR_NOMEM ) pCheck->mallocFailed = 1;
    checkAppendMsg(pCheck, "Failed to read ptrmap key=%d", iChild);
    return;
  }

  if( ePtrmapType!=eType || iPtrmapParent!=iParent ){
    checkAppendMsg(pCheck,
      "Bad ptr map entry key=%d expected=(%d,%d) got=(%d,%d)", 
      iChild, eType, iParent, ePtrmapType, iPtrmapParent);
  }
}
#endif

/*
................................................................................
** Check the integrity of the freelist or of an overflow page list.
** Verify that the number of pages on the list is N.
*/
static void checkList(
  IntegrityCk *pCheck,  /* Integrity checking context */
  int isFreeList,       /* True for a freelist.  False for overflow page list */
  int iPage,            /* Page number for first page in the list */
  int N                 /* Expected number of pages in the list */

){
  int i;
  int expected = N;
  int iFirst = iPage;
  while( N-- > 0 && pCheck->mxErr ){
    DbPage *pOvflPage;
    unsigned char *pOvflData;
    if( iPage<1 ){
      checkAppendMsg(pCheck,
         "%d of %d pages missing from overflow list starting at %d",
          N+1, expected, iFirst);
      break;
    }
    if( checkRef(pCheck, iPage) ) break;
    if( sqlite3PagerGet(pCheck->pPager, (Pgno)iPage, &pOvflPage) ){
      checkAppendMsg(pCheck, "failed to get page %d", iPage);
      break;
    }
    pOvflData = (unsigned char *)sqlite3PagerGetData(pOvflPage);
    if( isFreeList ){
      int n = get4byte(&pOvflData[4]);
#ifndef SQLITE_OMIT_AUTOVACUUM
      if( pCheck->pBt->autoVacuum ){
        checkPtrmap(pCheck, iPage, PTRMAP_FREEPAGE, 0);
      }
#endif
      if( n>(int)pCheck->pBt->usableSize/4-2 ){
        checkAppendMsg(pCheck,
           "freelist leaf count too big on page %d", iPage);
        N--;
      }else{
        for(i=0; i<n; i++){
          Pgno iFreePage = get4byte(&pOvflData[8+i*4]);
#ifndef SQLITE_OMIT_AUTOVACUUM
          if( pCheck->pBt->autoVacuum ){
            checkPtrmap(pCheck, iFreePage, PTRMAP_FREEPAGE, 0);
          }
#endif
          checkRef(pCheck, iFreePage);
        }
        N -= n;
      }
    }
#ifndef SQLITE_OMIT_AUTOVACUUM
    else{
      /* If this database supports auto-vacuum and iPage is not the last
      ** page in this overflow list, check that the pointer-map entry for
      ** the following page matches iPage.
      */
      if( pCheck->pBt->autoVacuum && N>0 ){
        i = get4byte(pOvflData);
        checkPtrmap(pCheck, i, PTRMAP_OVERFLOW2, iPage);
      }
    }
#endif
    iPage = get4byte(pOvflData);
    sqlite3PagerUnref(pOvflPage);
  }
}
................................................................................
**      7.  Verify that the depth of all children is the same.
**      8.  Make sure this page is at least 33% full or else it is
**          the root of the tree.
*/
static int checkTreePage(
  IntegrityCk *pCheck,  /* Context for the sanity check */
  int iPage,            /* Page number of the page to check */

  i64 *pnParentMinKey, 
  i64 *pnParentMaxKey
){
  MemPage *pPage;
  int i, rc, depth, d2, pgno, cnt;
  int hdr, cellStart;
  int nCell;
  u8 *data;
  BtShared *pBt;
  int usableSize;

  char *hit = 0;
  i64 nMinKey = 0;
  i64 nMaxKey = 0;
  const char *saved_zPfx = pCheck->zPfx;
  int saved_v1 = pCheck->v1;
  int saved_v2 = pCheck->v2;

  /* Check that the page exists
  */
  pBt = pCheck->pBt;
  usableSize = pBt->usableSize;
  if( iPage==0 ) return 0;
  if( checkRef(pCheck, iPage) ) return 0;
  pCheck->zPfx = "Page %d: ";
  pCheck->v1 = iPage;
  if( (rc = btreeGetPage(pBt, (Pgno)iPage, &pPage, 0))!=0 ){
    checkAppendMsg(pCheck,
       "unable to get the page. error code=%d", rc);

    depth = -1;
    goto end_of_check;
  }

  /* Clear MemPage.isInit to make sure the corruption detection code in
  ** btreeInitPage() is executed.  */
  pPage->isInit = 0;
  if( (rc = btreeInitPage(pPage))!=0 ){
    assert( rc==SQLITE_CORRUPT );  /* The only possible error from InitPage */
    checkAppendMsg(pCheck,
                   "btreeInitPage() returns error code %d", rc);
    releasePage(pPage);
    depth = -1;
    goto end_of_check;
  }

  /* Check out all the cells.
  */
  depth = 0;
  for(i=0; i<pPage->nCell && pCheck->mxErr; i++){
    u8 *pCell;
    u32 sz;
    CellInfo info;

    /* Check payload overflow pages
    */

    pCheck->zPfx = "On tree page %d cell %d: ";
    pCheck->v1 = iPage;
    pCheck->v2 = i;
    pCell = findCell(pPage,i);
    btreeParseCellPtr(pPage, pCell, &info);
    sz = info.nPayload;

    /* For intKey pages, check that the keys are in order.
    */
    if( pPage->intKey ){
      if( i==0 ){
        nMinKey = nMaxKey = info.nKey;

      }else if( info.nKey <= nMaxKey ){
        checkAppendMsg(pCheck,
           "Rowid %lld out of order (previous was %lld)", info.nKey, nMaxKey);
      }
      nMaxKey = info.nKey;
    }

    if( (sz>info.nLocal) 
     && (&pCell[info.iOverflow]<=&pPage->aData[pBt->usableSize])
    ){
      int nPage = (sz - info.nLocal + usableSize - 5)/(usableSize - 4);
      Pgno pgnoOvfl = get4byte(&pCell[info.iOverflow]);
#ifndef SQLITE_OMIT_AUTOVACUUM
      if( pBt->autoVacuum ){
        checkPtrmap(pCheck, pgnoOvfl, PTRMAP_OVERFLOW1, iPage);
      }
#endif
      checkList(pCheck, 0, pgnoOvfl, nPage);
    }

    /* Check sanity of left child page.
    */
    if( !pPage->leaf ){
      pgno = get4byte(pCell);
#ifndef SQLITE_OMIT_AUTOVACUUM
      if( pBt->autoVacuum ){
        checkPtrmap(pCheck, pgno, PTRMAP_BTREE, iPage);
      }
#endif
      d2 = checkTreePage(pCheck, pgno, &nMinKey, i==0?NULL:&nMaxKey);
      if( i>0 && d2!=depth ){
        checkAppendMsg(pCheck, "Child page depth differs");
      }
      depth = d2;
    }
  }

  if( !pPage->leaf ){
    pgno = get4byte(&pPage->aData[pPage->hdrOffset+8]);

    pCheck->zPfx = "On page %d at right child: ";
    pCheck->v1 = iPage;
#ifndef SQLITE_OMIT_AUTOVACUUM
    if( pBt->autoVacuum ){
      checkPtrmap(pCheck, pgno, PTRMAP_BTREE, iPage);
    }
#endif
    checkTreePage(pCheck, pgno, NULL, !pPage->nCell?NULL:&nMaxKey);
  }
 
  /* For intKey leaf pages, check that the min/max keys are in order
  ** with any left/parent/right pages.
  */
  pCheck->zPfx = "Page %d: ";
  pCheck->v1 = iPage;
  if( pPage->leaf && pPage->intKey ){
    /* if we are a left child page */
    if( pnParentMinKey ){
      /* if we are the left most child page */
      if( !pnParentMaxKey ){
        if( nMaxKey > *pnParentMinKey ){
          checkAppendMsg(pCheck,
              "Rowid %lld out of order (max larger than parent min of %lld)",
              nMaxKey, *pnParentMinKey);
        }
      }else{
        if( nMinKey <= *pnParentMinKey ){
          checkAppendMsg(pCheck,
              "Rowid %lld out of order (min less than parent min of %lld)",
              nMinKey, *pnParentMinKey);
        }
        if( nMaxKey > *pnParentMaxKey ){
          checkAppendMsg(pCheck,
              "Rowid %lld out of order (max larger than parent max of %lld)",
              nMaxKey, *pnParentMaxKey);
        }
        *pnParentMinKey = nMaxKey;
      }
    /* else if we're a right child page */
    } else if( pnParentMaxKey ){
      if( nMinKey <= *pnParentMaxKey ){
        checkAppendMsg(pCheck,
            "Rowid %lld out of order (min less than parent max of %lld)",
            nMinKey, *pnParentMaxKey);
      }
    }
  }

  /* Check for complete coverage of the page
  */
  data = pPage->aData;
  hdr = pPage->hdrOffset;
  hit = sqlite3PageMalloc( pBt->pageSize );
  pCheck->zPfx = 0;
  if( hit==0 ){
    pCheck->mallocFailed = 1;
  }else{
    int contentOffset = get2byteNotZero(&data[hdr+5]);
    assert( contentOffset<=usableSize );  /* Enforced by btreeInitPage() */
    memset(hit+contentOffset, 0, usableSize-contentOffset);
    memset(hit, 1, contentOffset);
................................................................................
      int pc = get2byte(&data[cellStart+i*2]);
      u32 size = 65536;
      int j;
      if( pc<=usableSize-4 ){
        size = cellSizePtr(pPage, &data[pc]);
      }
      if( (int)(pc+size-1)>=usableSize ){
        pCheck->zPfx = 0;
        checkAppendMsg(pCheck,
            "Corruption detected in cell %d on page %d",i,iPage);
      }else{
        for(j=pc+size-1; j>=pc; j--) hit[j]++;
      }
    }
    i = get2byte(&data[hdr+1]);
    while( i>0 ){
................................................................................
      assert( j<=usableSize-4 );   /* Enforced by btreeInitPage() */
      i = j;
    }
    for(i=cnt=0; i<usableSize; i++){
      if( hit[i]==0 ){
        cnt++;
      }else if( hit[i]>1 ){
        checkAppendMsg(pCheck,
          "Multiple uses for byte %d of page %d", i, iPage);
        break;
      }
    }
    if( cnt!=data[hdr+7] ){
      checkAppendMsg(pCheck,
          "Fragmentation of %d bytes reported as %d on page %d",
          cnt, data[hdr+7], iPage);
    }
  }
  sqlite3PageFree(hit);
  releasePage(pPage);

end_of_check:
  pCheck->zPfx = saved_zPfx;
  pCheck->v1 = saved_v1;
  pCheck->v2 = saved_v2;
  return depth+1;
}
#endif /* SQLITE_OMIT_INTEGRITY_CHECK */

#ifndef SQLITE_OMIT_INTEGRITY_CHECK
/*
** This routine does a complete check of the given BTree file.  aRoot[] is
................................................................................
  nRef = sqlite3PagerRefcount(pBt->pPager);
  sCheck.pBt = pBt;
  sCheck.pPager = pBt->pPager;
  sCheck.nPage = btreePagecount(sCheck.pBt);
  sCheck.mxErr = mxErr;
  sCheck.nErr = 0;
  sCheck.mallocFailed = 0;
  sCheck.zPfx = 0;
  sCheck.v1 = 0;
  sCheck.v2 = 0;
  *pnErr = 0;
  if( sCheck.nPage==0 ){
    sqlite3BtreeLeave(p);
    return 0;
  }

  sCheck.aPgRef = sqlite3MallocZero((sCheck.nPage / 8)+ 1);
................................................................................
  i = PENDING_BYTE_PAGE(pBt);
  if( i<=sCheck.nPage ) setPageReferenced(&sCheck, i);
  sqlite3StrAccumInit(&sCheck.errMsg, zErr, sizeof(zErr), SQLITE_MAX_LENGTH);
  sCheck.errMsg.useMalloc = 2;

  /* Check the integrity of the freelist
  */
  sCheck.zPfx = "Main freelist: ";
  checkList(&sCheck, 1, get4byte(&pBt->pPage1->aData[32]),
            get4byte(&pBt->pPage1->aData[36]));
  sCheck.zPfx = 0;

  /* Check all the tables.
  */
  for(i=0; (int)i<nRoot && sCheck.mxErr; i++){
    if( aRoot[i]==0 ) continue;
#ifndef SQLITE_OMIT_AUTOVACUUM
    if( pBt->autoVacuum && aRoot[i]>1 ){
      checkPtrmap(&sCheck, aRoot[i], PTRMAP_ROOTPAGE, 0);
    }
#endif
    sCheck.zPfx = "List of tree roots: ";
    checkTreePage(&sCheck, aRoot[i], NULL, NULL);
    sCheck.zPfx = 0;
  }

  /* Make sure every page in the file is referenced
  */
  for(i=1; i<=sCheck.nPage && sCheck.mxErr; i++){
#ifdef SQLITE_OMIT_AUTOVACUUM
    if( getPageReferenced(&sCheck, i)==0 ){
      checkAppendMsg(&sCheck, "Page %d is never used", i);
    }
#else
    /* If the database supports auto-vacuum, make sure no tables contain
    ** references to pointer-map pages.
    */
    if( getPageReferenced(&sCheck, i)==0 && 
       (PTRMAP_PAGENO(pBt, i)!=i || !pBt->autoVacuum) ){
      checkAppendMsg(&sCheck, "Page %d is never used", i);
    }
    if( getPageReferenced(&sCheck, i)!=0 && 
       (PTRMAP_PAGENO(pBt, i)==i && pBt->autoVacuum) ){
      checkAppendMsg(&sCheck, "Pointer map page %d is referenced", i);
    }
#endif
  }

  /* Make sure this analysis did not leave any unref() pages.
  ** This is an internal consistency check; an integrity check
  ** of the integrity check.
  */
  if( NEVER(nRef != sqlite3PagerRefcount(pBt->pPager)) ){
    checkAppendMsg(&sCheck,
      "Outstanding page count goes from %d to %d during this analysis",
      nRef, sqlite3PagerRefcount(pBt->pPager)
    );
  }

  /* Clean  up and report errors.
  */
................................................................................
    return SQLITE_ABORT;
  }

  /* Save the positions of all other cursors open on this table. This is
  ** required in case any of them are holding references to an xFetch
  ** version of the b-tree page modified by the accessPayload call below.
  **
  ** Note that pCsr must be open on a INTKEY table and saveCursorPosition()
  ** and hence saveAllCursors() cannot fail on a BTREE_INTKEY table, hence
  ** saveAllCursors can only return SQLITE_OK.
  */
  VVA_ONLY(rc =) saveAllCursors(pCsr->pBt, pCsr->pgnoRoot, pCsr);
  assert( rc==SQLITE_OK );

  /* Check some assumptions: 

**
** Access to all fields of this structure is controlled by the mutex
** stored in MemPage.pBt->mutex.
*/
struct MemPage {
  u8 isInit;           /* True if previously initialized. MUST BE FIRST! */
  u8 nOverflow;        /* Number of overflow cell bodies in aCell[] */
  u8 intKey;           /* True if intkey flag is set */


  u8 leaf;             /* True if leaf flag is set */
  u8 hasData;          /* True if this page stores data */
  u8 hdrOffset;        /* 100 for page 1.  0 otherwise */
  u8 childPtrSize;     /* 0 if leaf==1.  4 if leaf==0 */
  u8 max1bytePayload;  /* min(maxLocal,127) */
  u16 maxLocal;        /* Copy of BtShared.maxLocal or BtShared.maxLeaf */
  u16 minLocal;        /* Copy of BtShared.minLocal or BtShared.minLeaf */
  u16 cellOffset;      /* Index in aData of first cell pointer */
  u16 nFree;           /* Number of free bytes on the page */
................................................................................
  Bitvec *pHasContent;  /* Set of pages moved to free-list this transaction */
#ifndef SQLITE_OMIT_SHARED_CACHE
  int nRef;             /* Number of references to this structure */
  BtShared *pNext;      /* Next on a list of sharable BtShared structs */
  BtLock *pLock;        /* List of locks held on this shared-btree struct */
  Btree *pWriter;       /* Btree with currently open write transaction */
#endif
  u8 *pTmpSpace;        /* BtShared.pageSize bytes of space for tmp use */
};

/*
** Allowed values for BtShared.btsFlags
*/
#define BTS_READ_ONLY        0x0001   /* Underlying file is readonly */
#define BTS_PAGESIZE_FIXED   0x0002   /* Page size can no longer be changed */
................................................................................
/*
** An instance of the following structure is used to hold information
** about a cell.  The parseCellPtr() function fills in this structure
** based on information extract from the raw disk page.
*/
typedef struct CellInfo CellInfo;
struct CellInfo {
  i64 nKey;      /* The key for INTKEY tables, or number of bytes in key */
  u8 *pCell;     /* Pointer to the start of cell content */
  u32 nData;     /* Number of bytes of data */
  u32 nPayload;  /* Total amount of payload */
  u16 nHeader;   /* Size of the cell content header in bytes */
  u16 nLocal;    /* Amount of payload held locally */
  u16 iOverflow; /* Offset to overflow page number.  Zero if no overflow */
  u16 nSize;     /* Size of the cell content on the main b-tree page */
};

/*
** Maximum depth of an SQLite B-Tree structure. Any B-Tree deeper than
** this will be declared corrupt. This value is calculated based on a
................................................................................
  BtShared *pBt;    /* The tree being checked out */
  Pager *pPager;    /* The associated pager.  Also accessible by pBt->pPager */
  u8 *aPgRef;       /* 1 bit per page in the db (see above) */
  Pgno nPage;       /* Number of pages in the database */
  int mxErr;        /* Stop accumulating errors when this reaches zero */
  int nErr;         /* Number of messages written to zErrMsg so far */
  int mallocFailed; /* A memory allocation error has occurred */


  StrAccum errMsg;  /* Accumulate the error message text here */
};

/*
** Routines to read or write a two- and four-byte big-endian integer values.
*/
#define get2byte(x)   ((x)[0]<<8 | (x)[1])
#define put2byte(p,v) ((p)[0] = (u8)((v)>>8), (p)[1] = (u8)(v))
#define get4byte sqlite3Get4byte
#define put4byte sqlite3Put4byte

**
** Access to all fields of this structure is controlled by the mutex
** stored in MemPage.pBt->mutex.
*/
struct MemPage {
  u8 isInit;           /* True if previously initialized. MUST BE FIRST! */
  u8 nOverflow;        /* Number of overflow cell bodies in aCell[] */
  u8 intKey;           /* True if table b-trees.  False for index b-trees */
  u8 intKeyLeaf;       /* True if the leaf of an intKey table */
  u8 noPayload;        /* True if internal intKey page (thus w/o data) */
  u8 leaf;             /* True if a leaf page */

  u8 hdrOffset;        /* 100 for page 1.  0 otherwise */
  u8 childPtrSize;     /* 0 if leaf==1.  4 if leaf==0 */
  u8 max1bytePayload;  /* min(maxLocal,127) */
  u16 maxLocal;        /* Copy of BtShared.maxLocal or BtShared.maxLeaf */
  u16 minLocal;        /* Copy of BtShared.minLocal or BtShared.minLeaf */
  u16 cellOffset;      /* Index in aData of first cell pointer */
  u16 nFree;           /* Number of free bytes on the page */
................................................................................
  Bitvec *pHasContent;  /* Set of pages moved to free-list this transaction */
#ifndef SQLITE_OMIT_SHARED_CACHE
  int nRef;             /* Number of references to this structure */
  BtShared *pNext;      /* Next on a list of sharable BtShared structs */
  BtLock *pLock;        /* List of locks held on this shared-btree struct */
  Btree *pWriter;       /* Btree with currently open write transaction */
#endif
  u8 *pTmpSpace;        /* Temp space sufficient to hold a single cell */
};

/*
** Allowed values for BtShared.btsFlags
*/
#define BTS_READ_ONLY        0x0001   /* Underlying file is readonly */
#define BTS_PAGESIZE_FIXED   0x0002   /* Page size can no longer be changed */
................................................................................
/*
** An instance of the following structure is used to hold information
** about a cell.  The parseCellPtr() function fills in this structure
** based on information extract from the raw disk page.
*/
typedef struct CellInfo CellInfo;
struct CellInfo {
  i64 nKey;      /* The key for INTKEY tables, or nPayload otherwise */
  u8 *pPayload;  /* Pointer to the start of payload */

  u32 nPayload;  /* Bytes of payload */

  u16 nLocal;    /* Amount of payload held locally, not on overflow */
  u16 iOverflow; /* Offset to overflow page number.  Zero if no overflow */
  u16 nSize;     /* Size of the cell content on the main b-tree page */
};

/*
** Maximum depth of an SQLite B-Tree structure. Any B-Tree deeper than
** this will be declared corrupt. This value is calculated based on a
................................................................................
  BtShared *pBt;    /* The tree being checked out */
  Pager *pPager;    /* The associated pager.  Also accessible by pBt->pPager */
  u8 *aPgRef;       /* 1 bit per page in the db (see above) */
  Pgno nPage;       /* Number of pages in the database */
  int mxErr;        /* Stop accumulating errors when this reaches zero */
  int nErr;         /* Number of messages written to zErrMsg so far */
  int mallocFailed; /* A memory allocation error has occurred */
  const char *zPfx; /* Error message prefix */
  int v1, v2;       /* Values for up to two %d fields in zPfx */
  StrAccum errMsg;  /* Accumulate the error message text here */
};

/*
** Routines to read or write a two- and four-byte big-endian integer values.
*/
#define get2byte(x)   ((x)[0]<<8 | (x)[1])
#define put2byte(p,v) ((p)[0] = (u8)((v)>>8), (p)[1] = (u8)(v))
#define get4byte sqlite3Get4byte
#define put4byte sqlite3Put4byte

#ifndef SQLITE_OMIT_ANALYZE
  sqlite3DeleteIndexSamples(db, p);
#endif
  if( db==0 || db->pnBytesFreed==0 ) sqlite3KeyInfoUnref(p->pKeyInfo);
  sqlite3ExprDelete(db, p->pPartIdxWhere);
  sqlite3DbFree(db, p->zColAff);
  if( p->isResized ) sqlite3DbFree(db, p->azColl);



  sqlite3DbFree(db, p);
}

/*
** For the index called zIdxName which is found in the database iDb,
** unlike that index from its Table then remove the index from
** the index hash table and free all memory structures associated
................................................................................
    }
  }

  /* If pszEst is not NULL, store an estimate of the field size.  The
  ** estimate is scaled so that the size of an integer is 1.  */
  if( pszEst ){
    *pszEst = 1;   /* default size is approx 4 bytes */
    if( aff<=SQLITE_AFF_NONE ){
      if( zChar ){
        while( zChar[0] ){
          if( sqlite3Isdigit(zChar[0]) ){
            int v = 0;
            sqlite3GetInt32(zChar, &v);
            v = v/4 + 1;
            if( v>255 ) v = 255;
................................................................................
void sqlite3AddDefaultValue(Parse *pParse, ExprSpan *pSpan){
  Table *p;
  Column *pCol;
  sqlite3 *db = pParse->db;
  p = pParse->pNewTable;
  if( p!=0 ){
    pCol = &(p->aCol[p->nCol-1]);
    if( !sqlite3ExprIsConstantOrFunction(pSpan->pExpr) ){
      sqlite3ErrorMsg(pParse, "default value of column [%s] is not constant",
          pCol->zName);
    }else{
      /* A copy of pExpr is used instead of the original, as pExpr contains
      ** tokens that point to volatile memory. The 'span' of the expression
      ** is required by pragma table_info.
      */
................................................................................
  }
  sqlite3_snprintf(n, zStmt, "CREATE TABLE ");
  k = sqlite3Strlen30(zStmt);
  identPut(zStmt, &k, p->zName);
  zStmt[k++] = '(';
  for(pCol=p->aCol, i=0; i<p->nCol; i++, pCol++){
    static const char * const azType[] = {
        /* SQLITE_AFF_TEXT    */ " TEXT",
        /* SQLITE_AFF_NONE    */ "",

        /* SQLITE_AFF_NUMERIC */ " NUM",
        /* SQLITE_AFF_INTEGER */ " INT",
        /* SQLITE_AFF_REAL    */ " REAL"
    };
    int len;
    const char *zType;

    sqlite3_snprintf(n-k, &zStmt[k], zSep);
    k += sqlite3Strlen30(&zStmt[k]);
    zSep = zSep2;
    identPut(zStmt, &k, pCol->zName);
    assert( pCol->affinity-SQLITE_AFF_TEXT >= 0 );
    assert( pCol->affinity-SQLITE_AFF_TEXT < ArraySize(azType) );
    testcase( pCol->affinity==SQLITE_AFF_TEXT );
    testcase( pCol->affinity==SQLITE_AFF_NONE );
    testcase( pCol->affinity==SQLITE_AFF_NUMERIC );
    testcase( pCol->affinity==SQLITE_AFF_INTEGER );
    testcase( pCol->affinity==SQLITE_AFF_REAL );
    
    zType = azType[pCol->affinity - SQLITE_AFF_TEXT];
    len = sqlite3Strlen30(zType);
    assert( pCol->affinity==SQLITE_AFF_NONE 
            || pCol->affinity==sqlite3AffinityType(zType, 0) );
    memcpy(&zStmt[k], zType, len);
    k += len;
    assert( k<=n );
  }
................................................................................
    addr2 = sqlite3VdbeCurrentAddr(v);
    sqlite3VdbeAddOp4Int(v, OP_SorterCompare, iSorter, j2, regRecord,
                         pIndex->nKeyCol); VdbeCoverage(v);
    sqlite3UniqueConstraint(pParse, OE_Abort, pIndex);
  }else{
    addr2 = sqlite3VdbeCurrentAddr(v);
  }
  sqlite3VdbeAddOp2(v, OP_SorterData, iSorter, regRecord);
  sqlite3VdbeAddOp3(v, OP_IdxInsert, iIdx, regRecord, 1);
  sqlite3VdbeChangeP5(v, OPFLAG_USESEEKRESULT);
  sqlite3ReleaseTempReg(pParse, regRecord);
  sqlite3VdbeAddOp2(v, OP_SorterNext, iSorter, addr2); VdbeCoverage(v);
  sqlite3VdbeJumpHere(v, addr1);

  sqlite3VdbeAddOp1(v, OP_Close, iTab);

#ifndef SQLITE_OMIT_ANALYZE
  sqlite3DeleteIndexSamples(db, p);
#endif
  if( db==0 || db->pnBytesFreed==0 ) sqlite3KeyInfoUnref(p->pKeyInfo);
  sqlite3ExprDelete(db, p->pPartIdxWhere);
  sqlite3DbFree(db, p->zColAff);
  if( p->isResized ) sqlite3DbFree(db, p->azColl);
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
  sqlite3_free(p->aiRowEst);
#endif
  sqlite3DbFree(db, p);
}

/*
** For the index called zIdxName which is found in the database iDb,
** unlike that index from its Table then remove the index from
** the index hash table and free all memory structures associated
................................................................................
    }
  }

  /* If pszEst is not NULL, store an estimate of the field size.  The
  ** estimate is scaled so that the size of an integer is 1.  */
  if( pszEst ){
    *pszEst = 1;   /* default size is approx 4 bytes */
    if( aff<SQLITE_AFF_NUMERIC ){
      if( zChar ){
        while( zChar[0] ){
          if( sqlite3Isdigit(zChar[0]) ){
            int v = 0;
            sqlite3GetInt32(zChar, &v);
            v = v/4 + 1;
            if( v>255 ) v = 255;
................................................................................
void sqlite3AddDefaultValue(Parse *pParse, ExprSpan *pSpan){
  Table *p;
  Column *pCol;
  sqlite3 *db = pParse->db;
  p = pParse->pNewTable;
  if( p!=0 ){
    pCol = &(p->aCol[p->nCol-1]);
    if( !sqlite3ExprIsConstantOrFunction(pSpan->pExpr, db->init.busy) ){
      sqlite3ErrorMsg(pParse, "default value of column [%s] is not constant",
          pCol->zName);
    }else{
      /* A copy of pExpr is used instead of the original, as pExpr contains
      ** tokens that point to volatile memory. The 'span' of the expression
      ** is required by pragma table_info.
      */
................................................................................
  }
  sqlite3_snprintf(n, zStmt, "CREATE TABLE ");
  k = sqlite3Strlen30(zStmt);
  identPut(zStmt, &k, p->zName);
  zStmt[k++] = '(';
  for(pCol=p->aCol, i=0; i<p->nCol; i++, pCol++){
    static const char * const azType[] = {

        /* SQLITE_AFF_NONE    */ "",
        /* SQLITE_AFF_TEXT    */ " TEXT",
        /* SQLITE_AFF_NUMERIC */ " NUM",
        /* SQLITE_AFF_INTEGER */ " INT",
        /* SQLITE_AFF_REAL    */ " REAL"
    };
    int len;
    const char *zType;

    sqlite3_snprintf(n-k, &zStmt[k], zSep);
    k += sqlite3Strlen30(&zStmt[k]);
    zSep = zSep2;
    identPut(zStmt, &k, pCol->zName);
    assert( pCol->affinity-SQLITE_AFF_NONE >= 0 );
    assert( pCol->affinity-SQLITE_AFF_NONE < ArraySize(azType) );
    testcase( pCol->affinity==SQLITE_AFF_NONE );
    testcase( pCol->affinity==SQLITE_AFF_TEXT );
    testcase( pCol->affinity==SQLITE_AFF_NUMERIC );
    testcase( pCol->affinity==SQLITE_AFF_INTEGER );
    testcase( pCol->affinity==SQLITE_AFF_REAL );
    
    zType = azType[pCol->affinity - SQLITE_AFF_NONE];
    len = sqlite3Strlen30(zType);
    assert( pCol->affinity==SQLITE_AFF_NONE 
            || pCol->affinity==sqlite3AffinityType(zType, 0) );
    memcpy(&zStmt[k], zType, len);
    k += len;
    assert( k<=n );
  }
................................................................................
    addr2 = sqlite3VdbeCurrentAddr(v);
    sqlite3VdbeAddOp4Int(v, OP_SorterCompare, iSorter, j2, regRecord,
                         pIndex->nKeyCol); VdbeCoverage(v);
    sqlite3UniqueConstraint(pParse, OE_Abort, pIndex);
  }else{
    addr2 = sqlite3VdbeCurrentAddr(v);
  }
  sqlite3VdbeAddOp3(v, OP_SorterData, iSorter, regRecord, iIdx);
  sqlite3VdbeAddOp3(v, OP_IdxInsert, iIdx, regRecord, 1);
  sqlite3VdbeChangeP5(v, OPFLAG_USESEEKRESULT);
  sqlite3ReleaseTempReg(pParse, regRecord);
  sqlite3VdbeAddOp2(v, OP_SorterNext, iSorter, addr2); VdbeCoverage(v);
  sqlite3VdbeJumpHere(v, addr1);

  sqlite3VdbeAddOp1(v, OP_Close, iTab);

  if( sqlite3StrNICmp(zOptName, "SQLITE_", 7)==0 ) zOptName += 7;
  n = sqlite3Strlen30(zOptName);

  /* Since ArraySize(azCompileOpt) is normally in single digits, a
  ** linear search is adequate.  No need for a binary search. */
  for(i=0; i<ArraySize(azCompileOpt); i++){
    if( sqlite3StrNICmp(zOptName, azCompileOpt[i], n)==0
     && sqlite3CtypeMap[(unsigned char)azCompileOpt[i][n]]==0
    ){
      return 1;
    }
  }
  return 0;
}

  if( sqlite3StrNICmp(zOptName, "SQLITE_", 7)==0 ) zOptName += 7;
  n = sqlite3Strlen30(zOptName);

  /* Since ArraySize(azCompileOpt) is normally in single digits, a
  ** linear search is adequate.  No need for a binary search. */
  for(i=0; i<ArraySize(azCompileOpt); i++){
    if( sqlite3StrNICmp(zOptName, azCompileOpt[i], n)==0
     && sqlite3IsIdChar((unsigned char)azCompileOpt[i][n])==0
    ){
      return 1;
    }
  }
  return 0;
}

  pNew->iLimit = 0;
  pNew->iOffset = 0;
  pNew->selFlags = p->selFlags & ~SF_UsesEphemeral;
  pNew->addrOpenEphm[0] = -1;
  pNew->addrOpenEphm[1] = -1;
  pNew->nSelectRow = p->nSelectRow;
  pNew->pWith = withDup(db, p->pWith);

  return pNew;
}
#else
Select *sqlite3SelectDup(sqlite3 *db, Select *p, int flags){
  assert( p==0 );
  return 0;
}
................................................................................
  sqlite3DbFree(db, pList->a);
  sqlite3DbFree(db, pList);
}

/*
** These routines are Walker callbacks.  Walker.u.pi is a pointer
** to an integer.  These routines are checking an expression to see
** if it is a constant.  Set *Walker.u.pi to 0 if the expression is
** not constant.
**
** These callback routines are used to implement the following:
**
**     sqlite3ExprIsConstant()
**     sqlite3ExprIsConstantNotJoin()
**     sqlite3ExprIsConstantOrFunction()
**








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

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

  switch( pExpr->op ){
    /* Consider functions to be constant if all their arguments are constant
    ** and either pWalker->u.i==2 or the function as the SQLITE_FUNC_CONST
    ** flag. */
    case TK_FUNCTION:
      if( pWalker->u.i==2 || ExprHasProperty(pExpr,EP_Constant) ){
        return WRC_Continue;
      }
      /* Fall through */
    case TK_ID:
    case TK_COLUMN:
    case TK_AGG_FUNCTION:
    case TK_AGG_COLUMN:
      testcase( pExpr->op==TK_ID );
      testcase( pExpr->op==TK_COLUMN );
      testcase( pExpr->op==TK_AGG_FUNCTION );
      testcase( pExpr->op==TK_AGG_COLUMN );
      pWalker->u.i = 0;
      return WRC_Abort;













    default:
      testcase( pExpr->op==TK_SELECT ); /* selectNodeIsConstant will disallow */
      testcase( pExpr->op==TK_EXISTS ); /* selectNodeIsConstant will disallow */
      return WRC_Continue;
  }
}
static int selectNodeIsConstant(Walker *pWalker, Select *NotUsed){
................................................................................
/*
** Walk an expression tree.  Return 1 if the expression is constant
** that does no originate from the ON or USING clauses of a join.
** Return 0 if it involves variables or function calls or terms from
** an ON or USING clause.
*/
int sqlite3ExprIsConstantNotJoin(Expr *p){
  return exprIsConst(p, 3);
}

/*
** Walk an expression tree.  Return 1 if the expression is constant
** or a function call with constant arguments.  Return and 0 if there
** are any variables.
**
** For the purposes of this function, a double-quoted string (ex: "abc")
** is considered a variable but a single-quoted string (ex: 'abc') is
** a constant.
*/
int sqlite3ExprIsConstantOrFunction(Expr *p){

  return exprIsConst(p, 2);
}

/*
** If the expression p codes a constant integer that is small enough
** to fit in a 32-bit integer, return 1 and put the value of the integer
** in *pValue.  If the expression is not an integer or if it is too big
** to fit in a signed 32-bit integer, return 0 and leave *pValue unchanged.
................................................................................
  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.
*/
void sqlite3ExplainExpr(Vdbe *pOut, Expr *pExpr){
  int op;                   /* The opcode being coded */
  const char *zBinOp = 0;   /* Binary operator */
  const char *zUniOp = 0;   /* Unary operator */

  if( pExpr==0 ){
    op = TK_NULL;
  }else{
    op = pExpr->op;
  }
  switch( op ){
    case TK_AGG_COLUMN: {
      sqlite3ExplainPrintf(pOut, "AGG{%d:%d}",
            pExpr->iTable, pExpr->iColumn);
      break;
    }
    case TK_COLUMN: {
      if( pExpr->iTable<0 ){
        /* This only happens when coding check constraints */
        sqlite3ExplainPrintf(pOut, "COLUMN(%d)", pExpr->iColumn);
      }else{
        sqlite3ExplainPrintf(pOut, "{%d:%d}",
                             pExpr->iTable, pExpr->iColumn);
      }
      break;
    }
    case TK_INTEGER: {
      if( pExpr->flags & EP_IntValue ){
        sqlite3ExplainPrintf(pOut, "%d", pExpr->u.iValue);
      }else{
        sqlite3ExplainPrintf(pOut, "%s", pExpr->u.zToken);
      }
      break;
    }
#ifndef SQLITE_OMIT_FLOATING_POINT
    case TK_FLOAT: {
      sqlite3ExplainPrintf(pOut,"%s", pExpr->u.zToken);
      break;
    }
#endif
    case TK_STRING: {
      sqlite3ExplainPrintf(pOut,"%Q", pExpr->u.zToken);
      break;
    }
    case TK_NULL: {
      sqlite3ExplainPrintf(pOut,"NULL");
      break;
    }
#ifndef SQLITE_OMIT_BLOB_LITERAL
    case TK_BLOB: {
      sqlite3ExplainPrintf(pOut,"%s", pExpr->u.zToken);
      break;
    }
#endif
    case TK_VARIABLE: {
      sqlite3ExplainPrintf(pOut,"VARIABLE(%s,%d)",
                           pExpr->u.zToken, pExpr->iColumn);
      break;
    }
    case TK_REGISTER: {
      sqlite3ExplainPrintf(pOut,"REGISTER(%d)", pExpr->iTable);
      break;
    }
    case TK_AS: {
      sqlite3ExplainExpr(pOut, pExpr->pLeft);





      break;
    }
#ifndef SQLITE_OMIT_CAST
    case TK_CAST: {
      /* Expressions of the form:   CAST(pLeft AS token) */
      const char *zAff = "unk";
      switch( sqlite3AffinityType(pExpr->u.zToken, 0) ){
        case SQLITE_AFF_TEXT:    zAff = "TEXT";     break;
        case SQLITE_AFF_NONE:    zAff = "NONE";     break;
        case SQLITE_AFF_NUMERIC: zAff = "NUMERIC";  break;
        case SQLITE_AFF_INTEGER: zAff = "INTEGER";  break;
        case SQLITE_AFF_REAL:    zAff = "REAL";     break;
      }
      sqlite3ExplainPrintf(pOut, "CAST-%s(", zAff);
      sqlite3ExplainExpr(pOut, pExpr->pLeft);
      sqlite3ExplainPrintf(pOut, ")");
      break;
    }
#endif /* SQLITE_OMIT_CAST */
    case TK_LT:      zBinOp = "LT";     break;
    case TK_LE:      zBinOp = "LE";     break;
    case TK_GT:      zBinOp = "GT";     break;
    case TK_GE:      zBinOp = "GE";     break;
................................................................................
    case TK_REM:     zBinOp = "REM";    break;
    case TK_BITAND:  zBinOp = "BITAND"; break;
    case TK_BITOR:   zBinOp = "BITOR";  break;
    case TK_SLASH:   zBinOp = "DIV";    break;
    case TK_LSHIFT:  zBinOp = "LSHIFT"; break;
    case TK_RSHIFT:  zBinOp = "RSHIFT"; break;
    case TK_CONCAT:  zBinOp = "CONCAT"; break;


    case TK_UMINUS:  zUniOp = "UMINUS"; break;
    case TK_UPLUS:   zUniOp = "UPLUS";  break;
    case TK_BITNOT:  zUniOp = "BITNOT"; break;
    case TK_NOT:     zUniOp = "NOT";    break;
    case TK_ISNULL:  zUniOp = "ISNULL"; break;
    case TK_NOTNULL: zUniOp = "NOTNULL"; break;

    case TK_COLLATE: {
      sqlite3ExplainExpr(pOut, pExpr->pLeft);
      sqlite3ExplainPrintf(pOut,".COLLATE(%s)",pExpr->u.zToken);
      break;
    }

    case TK_AGG_FUNCTION:
    case TK_FUNCTION: {
      ExprList *pFarg;       /* List of function arguments */
      if( ExprHasProperty(pExpr, EP_TokenOnly) ){
        pFarg = 0;
      }else{
        pFarg = pExpr->x.pList;
      }
      if( op==TK_AGG_FUNCTION ){
        sqlite3ExplainPrintf(pOut, "AGG_FUNCTION%d:%s(",
                             pExpr->op2, pExpr->u.zToken);
      }else{
        sqlite3ExplainPrintf(pOut, "FUNCTION:%s(", pExpr->u.zToken);
      }
      if( pFarg ){
        sqlite3ExplainExprList(pOut, pFarg);
      }
      sqlite3ExplainPrintf(pOut, ")");
      break;
    }
#ifndef SQLITE_OMIT_SUBQUERY
    case TK_EXISTS: {
      sqlite3ExplainPrintf(pOut, "EXISTS(");
      sqlite3ExplainSelect(pOut, pExpr->x.pSelect);
      sqlite3ExplainPrintf(pOut,")");
      break;
    }
    case TK_SELECT: {
      sqlite3ExplainPrintf(pOut, "(");
      sqlite3ExplainSelect(pOut, pExpr->x.pSelect);
      sqlite3ExplainPrintf(pOut, ")");
      break;
    }
    case TK_IN: {
      sqlite3ExplainPrintf(pOut, "IN(");
      sqlite3ExplainExpr(pOut, pExpr->pLeft);
      sqlite3ExplainPrintf(pOut, ",");
      if( ExprHasProperty(pExpr, EP_xIsSelect) ){
        sqlite3ExplainSelect(pOut, pExpr->x.pSelect);
      }else{
        sqlite3ExplainExprList(pOut, pExpr->x.pList);

      }
      sqlite3ExplainPrintf(pOut, ")");
      break;
    }
#endif /* SQLITE_OMIT_SUBQUERY */

    /*
    **    x BETWEEN y AND z
    **
................................................................................
    ** Y is stored in pExpr->pList->a[0].pExpr.
    ** Z is stored in pExpr->pList->a[1].pExpr.
    */
    case TK_BETWEEN: {
      Expr *pX = pExpr->pLeft;
      Expr *pY = pExpr->x.pList->a[0].pExpr;
      Expr *pZ = pExpr->x.pList->a[1].pExpr;
      sqlite3ExplainPrintf(pOut, "BETWEEN(");
      sqlite3ExplainExpr(pOut, pX);
      sqlite3ExplainPrintf(pOut, ",");
      sqlite3ExplainExpr(pOut, pY);
      sqlite3ExplainPrintf(pOut, ",");
      sqlite3ExplainExpr(pOut, pZ);
      sqlite3ExplainPrintf(pOut, ")");
      break;
    }
    case TK_TRIGGER: {
      /* If the opcode is TK_TRIGGER, then the expression is a reference
      ** to a column in the new.* or old.* pseudo-tables available to
      ** trigger programs. In this case Expr.iTable is set to 1 for the
      ** new.* pseudo-table, or 0 for the old.* pseudo-table. Expr.iColumn
      ** is set to the column of the pseudo-table to read, or to -1 to
      ** read the rowid field.
      */
      sqlite3ExplainPrintf(pOut, "%s(%d)", 
          pExpr->iTable ? "NEW" : "OLD", pExpr->iColumn);
      break;
    }
    case TK_CASE: {
      sqlite3ExplainPrintf(pOut, "CASE(");
      sqlite3ExplainExpr(pOut, pExpr->pLeft);
      sqlite3ExplainPrintf(pOut, ",");
      sqlite3ExplainExprList(pOut, pExpr->x.pList);
      break;
    }
#ifndef SQLITE_OMIT_TRIGGER
    case TK_RAISE: {
      const char *zType = "unk";
      switch( pExpr->affinity ){
        case OE_Rollback:   zType = "rollback";  break;
        case OE_Abort:      zType = "abort";     break;
        case OE_Fail:       zType = "fail";      break;
        case OE_Ignore:     zType = "ignore";    break;
      }
      sqlite3ExplainPrintf(pOut, "RAISE-%s(%s)", zType, pExpr->u.zToken);
      break;
    }
#endif



  }

  if( zBinOp ){
    sqlite3ExplainPrintf(pOut,"%s(", zBinOp);
    sqlite3ExplainExpr(pOut, pExpr->pLeft);
    sqlite3ExplainPrintf(pOut,",");
    sqlite3ExplainExpr(pOut, pExpr->pRight);
    sqlite3ExplainPrintf(pOut,")");


  }else if( zUniOp ){
    sqlite3ExplainPrintf(pOut,"%s(", zUniOp);
    sqlite3ExplainExpr(pOut, pExpr->pLeft);
    sqlite3ExplainPrintf(pOut,")");

  }

}
#endif /* defined(SQLITE_ENABLE_TREE_EXPLAIN) */


#if defined(SQLITE_ENABLE_TREE_EXPLAIN)

/*
** Generate a human-readable explanation of an expression list.
*/
void sqlite3ExplainExprList(Vdbe *pOut, ExprList *pList){
  int i;
  if( pList==0 || pList->nExpr==0 ){
    sqlite3ExplainPrintf(pOut, "(empty-list)");
    return;
  }else if( pList->nExpr==1 ){
    sqlite3ExplainExpr(pOut, pList->a[0].pExpr);
  }else{
    sqlite3ExplainPush(pOut);
    for(i=0; i<pList->nExpr; i++){
      sqlite3ExplainPrintf(pOut, "item[%d] = ", i);
      sqlite3ExplainPush(pOut);
      sqlite3ExplainExpr(pOut, pList->a[i].pExpr);
      sqlite3ExplainPop(pOut);
      if( pList->a[i].zName ){


        sqlite3ExplainPrintf(pOut, " AS %s", pList->a[i].zName);
      }
      if( pList->a[i].bSpanIsTab ){
        sqlite3ExplainPrintf(pOut, " (%s)", pList->a[i].zSpan);
      }
      if( i<pList->nExpr-1 ){
        sqlite3ExplainNL(pOut);
      }
    }
    sqlite3ExplainPop(pOut);
  }

}
#endif /* SQLITE_DEBUG */

/*
** Generate code that pushes the value of every element of the given
** expression list into a sequence of registers beginning at target.
**

  pNew->iLimit = 0;
  pNew->iOffset = 0;
  pNew->selFlags = p->selFlags & ~SF_UsesEphemeral;
  pNew->addrOpenEphm[0] = -1;
  pNew->addrOpenEphm[1] = -1;
  pNew->nSelectRow = p->nSelectRow;
  pNew->pWith = withDup(db, p->pWith);
  sqlite3SelectSetName(pNew, p->zSelName);
  return pNew;
}
#else
Select *sqlite3SelectDup(sqlite3 *db, Select *p, int flags){
  assert( p==0 );
  return 0;
}
................................................................................
  sqlite3DbFree(db, pList->a);
  sqlite3DbFree(db, pList);
}

/*
** These routines are Walker callbacks.  Walker.u.pi is a pointer
** to an integer.  These routines are checking an expression to see
** if it is a constant.  Set *Walker.u.i to 0 if the expression is
** not constant.
**
** These callback routines are used to implement the following:
**
**     sqlite3ExprIsConstant()                  pWalker->u.i==1
**     sqlite3ExprIsConstantNotJoin()           pWalker->u.i==2
**     sqlite3ExprIsConstantOrFunction()        pWalker->u.i==3 or 4
**
** The sqlite3ExprIsConstantOrFunction() is used for evaluating expressions
** in a CREATE TABLE statement.  The Walker.u.i value is 4 when parsing
** an existing schema and 3 when processing a new statement.  A bound
** parameter raises an error for new statements, but is silently converted
** to NULL for existing schemas.  This allows sqlite_master tables that 
** contain a bound parameter because they were generated by older versions
** of SQLite to be parsed by newer versions of SQLite without raising a
** malformed schema error.
*/
static int exprNodeIsConstant(Walker *pWalker, Expr *pExpr){

  /* If pWalker->u.i is 2 then any term of the expression that comes from
  ** the ON or USING clauses of a join disqualifies the expression
  ** from being considered constant. */
  if( pWalker->u.i==2 && ExprHasProperty(pExpr, EP_FromJoin) ){
    pWalker->u.i = 0;
    return WRC_Abort;
  }

  switch( pExpr->op ){
    /* Consider functions to be constant if all their arguments are constant
    ** and either pWalker->u.i==3 or 4 or the function as the SQLITE_FUNC_CONST
    ** flag. */
    case TK_FUNCTION:
      if( pWalker->u.i>=3 || ExprHasProperty(pExpr,EP_Constant) ){
        return WRC_Continue;
      }
      /* Fall through */
    case TK_ID:
    case TK_COLUMN:
    case TK_AGG_FUNCTION:
    case TK_AGG_COLUMN:
      testcase( pExpr->op==TK_ID );
      testcase( pExpr->op==TK_COLUMN );
      testcase( pExpr->op==TK_AGG_FUNCTION );
      testcase( pExpr->op==TK_AGG_COLUMN );
      pWalker->u.i = 0;
      return WRC_Abort;
    case TK_VARIABLE:
      if( pWalker->u.i==4 ){
        /* Silently convert bound parameters that appear inside of CREATE
        ** statements into a NULL when parsing the CREATE statement text out
        ** of the sqlite_master table */
        pExpr->op = TK_NULL;
      }else if( pWalker->u.i==3 ){
        /* A bound parameter in a CREATE statement that originates from
        ** sqlite3_prepare() causes an error */
        pWalker->u.i = 0;
        return WRC_Abort;
      }
      /* Fall through */
    default:
      testcase( pExpr->op==TK_SELECT ); /* selectNodeIsConstant will disallow */
      testcase( pExpr->op==TK_EXISTS ); /* selectNodeIsConstant will disallow */
      return WRC_Continue;
  }
}
static int selectNodeIsConstant(Walker *pWalker, Select *NotUsed){
................................................................................
/*
** Walk an expression tree.  Return 1 if the expression is constant
** that does no originate from the ON or USING clauses of a join.
** Return 0 if it involves variables or function calls or terms from
** an ON or USING clause.
*/
int sqlite3ExprIsConstantNotJoin(Expr *p){
  return exprIsConst(p, 2);
}

/*
** Walk an expression tree.  Return 1 if the expression is constant
** or a function call with constant arguments.  Return and 0 if there
** are any variables.
**
** For the purposes of this function, a double-quoted string (ex: "abc")
** is considered a variable but a single-quoted string (ex: 'abc') is
** a constant.
*/
int sqlite3ExprIsConstantOrFunction(Expr *p, u8 isInit){
  assert( isInit==0 || isInit==1 );
  return exprIsConst(p, 3+isInit);
}

/*
** If the expression p codes a constant integer that is small enough
** to fit in a 32-bit integer, return 1 and put the value of the integer
** in *pValue.  If the expression is not an integer or if it is too big
** to fit in a signed 32-bit integer, return 0 and leave *pValue unchanged.
................................................................................
  assert( pExpr->op!=TK_REGISTER );
  sqlite3ExprCode(pParse, pExpr, target);
  iMem = ++pParse->nMem;
  sqlite3VdbeAddOp2(v, OP_Copy, target, iMem);
  exprToRegister(pExpr, iMem);
}

#ifdef SQLITE_DEBUG
/*
** Generate a human-readable explanation of an expression tree.
*/
void sqlite3TreeViewExpr(TreeView *pView, const Expr *pExpr, u8 moreToFollow){

  const char *zBinOp = 0;   /* Binary operator */
  const char *zUniOp = 0;   /* Unary operator */
  pView = sqlite3TreeViewPush(pView, moreToFollow);
  if( pExpr==0 ){
    sqlite3TreeViewLine(pView, "nil");
    sqlite3TreeViewPop(pView);
    return;
  }
  switch( pExpr->op ){
    case TK_AGG_COLUMN: {
      sqlite3TreeViewLine(pView, "AGG{%d:%d}",
            pExpr->iTable, pExpr->iColumn);
      break;
    }
    case TK_COLUMN: {
      if( pExpr->iTable<0 ){
        /* This only happens when coding check constraints */
        sqlite3TreeViewLine(pView, "COLUMN(%d)", pExpr->iColumn);
      }else{
        sqlite3TreeViewLine(pView, "{%d:%d}",
                             pExpr->iTable, pExpr->iColumn);
      }
      break;
    }
    case TK_INTEGER: {
      if( pExpr->flags & EP_IntValue ){
        sqlite3TreeViewLine(pView, "%d", pExpr->u.iValue);
      }else{
        sqlite3TreeViewLine(pView, "%s", pExpr->u.zToken);
      }
      break;
    }
#ifndef SQLITE_OMIT_FLOATING_POINT
    case TK_FLOAT: {
      sqlite3TreeViewLine(pView,"%s", pExpr->u.zToken);
      break;
    }
#endif
    case TK_STRING: {
      sqlite3TreeViewLine(pView,"%Q", pExpr->u.zToken);
      break;
    }
    case TK_NULL: {
      sqlite3TreeViewLine(pView,"NULL");
      break;
    }
#ifndef SQLITE_OMIT_BLOB_LITERAL
    case TK_BLOB: {
      sqlite3TreeViewLine(pView,"%s", pExpr->u.zToken);
      break;
    }
#endif
    case TK_VARIABLE: {
      sqlite3TreeViewLine(pView,"VARIABLE(%s,%d)",
                          pExpr->u.zToken, pExpr->iColumn);
      break;
    }
    case TK_REGISTER: {
      sqlite3TreeViewLine(pView,"REGISTER(%d)", pExpr->iTable);
      break;
    }
    case TK_AS: {
      sqlite3TreeViewLine(pView,"AS %Q", pExpr->u.zToken);
      sqlite3TreeViewExpr(pView, pExpr->pLeft, 0);
      break;
    }
    case TK_ID: {
      sqlite3TreeViewLine(pView,"ID %Q", pExpr->u.zToken);
      break;
    }
#ifndef SQLITE_OMIT_CAST
    case TK_CAST: {
      /* Expressions of the form:   CAST(pLeft AS token) */
      sqlite3TreeViewLine(pView,"CAST %Q", pExpr->u.zToken);
      sqlite3TreeViewExpr(pView, pExpr->pLeft, 0);









      break;
    }
#endif /* SQLITE_OMIT_CAST */
    case TK_LT:      zBinOp = "LT";     break;
    case TK_LE:      zBinOp = "LE";     break;
    case TK_GT:      zBinOp = "GT";     break;
    case TK_GE:      zBinOp = "GE";     break;
................................................................................
    case TK_REM:     zBinOp = "REM";    break;
    case TK_BITAND:  zBinOp = "BITAND"; break;
    case TK_BITOR:   zBinOp = "BITOR";  break;
    case TK_SLASH:   zBinOp = "DIV";    break;
    case TK_LSHIFT:  zBinOp = "LSHIFT"; break;
    case TK_RSHIFT:  zBinOp = "RSHIFT"; break;
    case TK_CONCAT:  zBinOp = "CONCAT"; break;
    case TK_DOT:     zBinOp = "DOT";    break;

    case TK_UMINUS:  zUniOp = "UMINUS"; break;
    case TK_UPLUS:   zUniOp = "UPLUS";  break;
    case TK_BITNOT:  zUniOp = "BITNOT"; break;
    case TK_NOT:     zUniOp = "NOT";    break;
    case TK_ISNULL:  zUniOp = "ISNULL"; break;
    case TK_NOTNULL: zUniOp = "NOTNULL"; break;

    case TK_COLLATE: {
      sqlite3TreeViewLine(pView, "COLLATE %Q", pExpr->u.zToken);
      sqlite3TreeViewExpr(pView, pExpr->pLeft, 0);
      break;
    }

    case TK_AGG_FUNCTION:
    case TK_FUNCTION: {
      ExprList *pFarg;       /* List of function arguments */
      if( ExprHasProperty(pExpr, EP_TokenOnly) ){
        pFarg = 0;
      }else{
        pFarg = pExpr->x.pList;
      }
      if( pExpr->op==TK_AGG_FUNCTION ){
        sqlite3TreeViewLine(pView, "AGG_FUNCTION%d %Q",
                             pExpr->op2, pExpr->u.zToken);
      }else{
        sqlite3TreeViewLine(pView, "FUNCTION %Q", pExpr->u.zToken);
      }
      if( pFarg ){
        sqlite3TreeViewExprList(pView, pFarg, 0, 0);
      }

      break;
    }
#ifndef SQLITE_OMIT_SUBQUERY
    case TK_EXISTS: {
      sqlite3TreeViewLine(pView, "EXISTS-expr");
      sqlite3TreeViewSelect(pView, pExpr->x.pSelect, 0);

      break;
    }
    case TK_SELECT: {
      sqlite3TreeViewLine(pView, "SELECT-expr");
      sqlite3TreeViewSelect(pView, pExpr->x.pSelect, 0);

      break;
    }
    case TK_IN: {
      sqlite3TreeViewLine(pView, "IN");
      sqlite3TreeViewExpr(pView, pExpr->pLeft, 1);

      if( ExprHasProperty(pExpr, EP_xIsSelect) ){
        sqlite3TreeViewSelect(pView, pExpr->x.pSelect, 0);
      }else{

        sqlite3TreeViewExprList(pView, pExpr->x.pList, 0, 0);
      }

      break;
    }
#endif /* SQLITE_OMIT_SUBQUERY */

    /*
    **    x BETWEEN y AND z
    **
................................................................................
    ** Y is stored in pExpr->pList->a[0].pExpr.
    ** Z is stored in pExpr->pList->a[1].pExpr.
    */
    case TK_BETWEEN: {
      Expr *pX = pExpr->pLeft;
      Expr *pY = pExpr->x.pList->a[0].pExpr;
      Expr *pZ = pExpr->x.pList->a[1].pExpr;
      sqlite3TreeViewLine(pView, "BETWEEN");
      sqlite3TreeViewExpr(pView, pX, 1);
      sqlite3TreeViewExpr(pView, pY, 1);
      sqlite3TreeViewExpr(pView, pZ, 0);



      break;
    }
    case TK_TRIGGER: {
      /* If the opcode is TK_TRIGGER, then the expression is a reference
      ** to a column in the new.* or old.* pseudo-tables available to
      ** trigger programs. In this case Expr.iTable is set to 1 for the
      ** new.* pseudo-table, or 0 for the old.* pseudo-table. Expr.iColumn
      ** is set to the column of the pseudo-table to read, or to -1 to
      ** read the rowid field.
      */
      sqlite3TreeViewLine(pView, "%s(%d)", 
          pExpr->iTable ? "NEW" : "OLD", pExpr->iColumn);
      break;
    }
    case TK_CASE: {
      sqlite3TreeViewLine(pView, "CASE");
      sqlite3TreeViewExpr(pView, pExpr->pLeft, 1);
      sqlite3TreeViewExprList(pView, pExpr->x.pList, 0, 0);

      break;
    }
#ifndef SQLITE_OMIT_TRIGGER
    case TK_RAISE: {
      const char *zType = "unk";
      switch( pExpr->affinity ){
        case OE_Rollback:   zType = "rollback";  break;
        case OE_Abort:      zType = "abort";     break;
        case OE_Fail:       zType = "fail";      break;
        case OE_Ignore:     zType = "ignore";    break;
      }
      sqlite3TreeViewLine(pView, "RAISE %s(%Q)", zType, pExpr->u.zToken);
      break;
    }
#endif
    default: {
      sqlite3TreeViewLine(pView, "op=%d", pExpr->op);
      break;
    }
  }
  if( zBinOp ){




    sqlite3TreeViewLine(pView, "%s", zBinOp);
    sqlite3TreeViewExpr(pView, pExpr->pLeft, 1);
    sqlite3TreeViewExpr(pView, pExpr->pRight, 0);
  }else if( zUniOp ){


    sqlite3TreeViewLine(pView, "%s", zUniOp);
    sqlite3TreeViewExpr(pView, pExpr->pLeft, 0);
  }
  sqlite3TreeViewPop(pView);
}

#endif /* SQLITE_DEBUG */


#ifdef SQLITE_DEBUG
/*
** Generate a human-readable explanation of an expression list.
*/
void sqlite3TreeViewExprList(
  TreeView *pView,
  const ExprList *pList,
  u8 moreToFollow,
  const char *zLabel
){
  int i;
  pView = sqlite3TreeViewPush(pView, moreToFollow);
  if( zLabel==0 || zLabel[0]==0 ) zLabel = "LIST";
  if( pList==0 ){
    sqlite3TreeViewLine(pView, "%s (empty)", zLabel);
  }else{
    sqlite3TreeViewLine(pView, "%s", zLabel);
    for(i=0; i<pList->nExpr; i++){
      sqlite3TreeViewExpr(pView, pList->a[i].pExpr, i<pList->nExpr-1);
#if 0
     if( pList->a[i].zName ){
        sqlite3ExplainPrintf(pOut, " AS %s", pList->a[i].zName);
      }
      if( pList->a[i].bSpanIsTab ){
        sqlite3ExplainPrintf(pOut, " (%s)", pList->a[i].zSpan);
      }
#endif

    }
  }


  sqlite3TreeViewPop(pView);
}
#endif /* SQLITE_DEBUG */

/*
** Generate code that pushes the value of every element of the given
** expression list into a sequence of registers beginning at target.
**

#include <assert.h>
#include "vdbeInt.h"

/*
** Return the collating function associated with a function.
*/
static CollSeq *sqlite3GetFuncCollSeq(sqlite3_context *context){
  return context->pColl;



}

/*
** Indicate that the accumulator load should be skipped on this
** iteration of the aggregate loop.
*/
static void sqlite3SkipAccumulatorLoad(sqlite3_context *context){
................................................................................
/*
** For LIKE and GLOB matching on EBCDIC machines, assume that every
** character is exactly one byte in size.  Also, all characters are
** able to participate in upper-case-to-lower-case mappings in EBCDIC
** whereas only characters less than 0x80 do in ASCII.
*/
#if defined(SQLITE_EBCDIC)
# define sqlite3Utf8Read(A)    (*((*A)++))
# define GlobUpperToLower(A)   A = sqlite3UpperToLower[A]

#else
# define GlobUpperToLower(A)   if( !((A)&~0x7f) ){ A = sqlite3UpperToLower[A]; }

#endif

static const struct compareInfo globInfo = { '*', '?', '[', 0 };
/* The correct SQL-92 behavior is for the LIKE operator to ignore
** case.  Thus  'a' LIKE 'A' would be true. */
static const struct compareInfo likeInfoNorm = { '%', '_',   0, 1 };
/* If SQLITE_CASE_SENSITIVE_LIKE is defined, then the LIKE operator
** is case sensitive causing 'a' LIKE 'A' to be false */
static const struct compareInfo likeInfoAlt = { '%', '_',   0, 0 };

/*
** Compare two UTF-8 strings for equality where the first string can
** potentially be a "glob" expression.  Return true (1) if they
** are the same and false (0) if they are different.
**
** Globbing rules:
**
**      '*'       Matches any sequence of zero or more characters.
**
**      '?'       Matches exactly one character.
................................................................................
**
** With the [...] and [^...] matching, a ']' character can be included
** in the list by making it the first character after '[' or '^'.  A
** range of characters can be specified using '-'.  Example:
** "[a-z]" matches any single lower-case letter.  To match a '-', make
** it the last character in the list.
**
** This routine is usually quick, but can be N**2 in the worst case.
**
** Hints: to match '*' or '?', put them in "[]".  Like this:
**
**         abc[*]xyz        Matches "abc*xyz" only







*/
static int patternCompare(
  const u8 *zPattern,              /* The glob pattern */
  const u8 *zString,               /* The string to compare against the glob */
  const struct compareInfo *pInfo, /* Information about how to do the compare */
  u32 esc                          /* The escape character */
){
  u32 c, c2;
  int invert;
  int seen;
  u8 matchOne = pInfo->matchOne;
  u8 matchAll = pInfo->matchAll;
  u8 matchSet = pInfo->matchSet;

  u8 noCase = pInfo->noCase; 


  int prevEscape = 0;     /* True if the previous character was 'escape' */






  while( (c = sqlite3Utf8Read(&zPattern))!=0 ){
    if( c==matchAll && !prevEscape ){



      while( (c=sqlite3Utf8Read(&zPattern)) == matchAll
               || c == matchOne ){
        if( c==matchOne && sqlite3Utf8Read(&zString)==0 ){
          return 0;
        }
      }
      if( c==0 ){
        return 1;
      }else if( c==esc ){

        c = sqlite3Utf8Read(&zPattern);
        if( c==0 ){
          return 0;
        }
      }else if( c==matchSet ){
        assert( esc==0 );         /* This is GLOB, not LIKE */
        assert( matchSet<0x80 );  /* '[' is a single-byte character */

        while( *zString && patternCompare(&zPattern[-1],zString,pInfo,esc)==0 ){
          SQLITE_SKIP_UTF8(zString);
        }
        return *zString!=0;
      }
      while( (c2 = sqlite3Utf8Read(&zString))!=0 ){













        if( noCase ){
          GlobUpperToLower(c2);
          GlobUpperToLower(c);
          while( c2 != 0 && c2 != c ){

            c2 = sqlite3Utf8Read(&zString);
            GlobUpperToLower(c2);


          }




        }else{
          while( c2 != 0 && c2 != c ){
            c2 = sqlite3Utf8Read(&zString);


          }
        }
        if( c2==0 ) return 0;
        if( patternCompare(zPattern,zString,pInfo,esc) ) return 1;
      }
      return 0;
    }else if( c==matchOne && !prevEscape ){

      if( sqlite3Utf8Read(&zString)==0 ){
        return 0;
      }
    }else if( c==matchSet ){


      u32 prior_c = 0;
      assert( esc==0 );    /* This only occurs for GLOB, not LIKE */
      seen = 0;
      invert = 0;
      c = sqlite3Utf8Read(&zString);
      if( c==0 ) return 0;
      c2 = sqlite3Utf8Read(&zPattern);
      if( c2=='^' ){
        invert = 1;
        c2 = sqlite3Utf8Read(&zPattern);
      }
      if( c2==']' ){
        if( c==']' ) seen = 1;
        c2 = sqlite3Utf8Read(&zPattern);
      }
      while( c2 && c2!=']' ){
        if( c2=='-' && zPattern[0]!=']' && zPattern[0]!=0 && prior_c>0 ){
          c2 = sqlite3Utf8Read(&zPattern);
          if( c>=prior_c && c<=c2 ) seen = 1;
          prior_c = 0;
        }else{
          if( c==c2 ){
            seen = 1;
          }
          prior_c = c2;
        }
        c2 = sqlite3Utf8Read(&zPattern);
      }
      if( c2==0 || (seen ^ invert)==0 ){
        return 0;
      }
    }else if( esc==c && !prevEscape ){
      prevEscape = 1;
    }else{
      c2 = sqlite3Utf8Read(&zString);
      if( noCase ){
        GlobUpperToLower(c);
        GlobUpperToLower(c2);

      }
      if( c!=c2 ){
        return 0;
      }
      prevEscape = 0;




    }


  }
  return *zString==0;
}

/*
** The sqlite3_strglob() interface.
*/

#include <assert.h>
#include "vdbeInt.h"

/*
** Return the collating function associated with a function.
*/
static CollSeq *sqlite3GetFuncCollSeq(sqlite3_context *context){
  VdbeOp *pOp = &context->pVdbe->aOp[context->iOp-1];
  assert( pOp->opcode==OP_CollSeq );
  assert( pOp->p4type==P4_COLLSEQ );
  return pOp->p4.pColl;
}

/*
** Indicate that the accumulator load should be skipped on this
** iteration of the aggregate loop.
*/
static void sqlite3SkipAccumulatorLoad(sqlite3_context *context){
................................................................................
/*
** For LIKE and GLOB matching on EBCDIC machines, assume that every
** character is exactly one byte in size.  Also, all characters are
** able to participate in upper-case-to-lower-case mappings in EBCDIC
** whereas only characters less than 0x80 do in ASCII.
*/
#if defined(SQLITE_EBCDIC)
# define sqlite3Utf8Read(A)        (*((*A)++))
# define GlobUpperToLower(A)       A = sqlite3UpperToLower[A]
# define GlobUpperToLowerAscii(A)  A = sqlite3UpperToLower[A]
#else
# define GlobUpperToLower(A)       if( A<=0x7f ){ A = sqlite3UpperToLower[A]; }
# define GlobUpperToLowerAscii(A)  A = sqlite3UpperToLower[A]
#endif

static const struct compareInfo globInfo = { '*', '?', '[', 0 };
/* The correct SQL-92 behavior is for the LIKE operator to ignore
** case.  Thus  'a' LIKE 'A' would be true. */
static const struct compareInfo likeInfoNorm = { '%', '_',   0, 1 };
/* If SQLITE_CASE_SENSITIVE_LIKE is defined, then the LIKE operator
** is case sensitive causing 'a' LIKE 'A' to be false */
static const struct compareInfo likeInfoAlt = { '%', '_',   0, 0 };

/*
** Compare two UTF-8 strings for equality where the first string can
** potentially be a "glob" or "like" expression.  Return true (1) if they
** are the same and false (0) if they are different.
**
** Globbing rules:
**
**      '*'       Matches any sequence of zero or more characters.
**
**      '?'       Matches exactly one character.
................................................................................
**
** With the [...] and [^...] matching, a ']' character can be included
** in the list by making it the first character after '[' or '^'.  A
** range of characters can be specified using '-'.  Example:
** "[a-z]" matches any single lower-case letter.  To match a '-', make
** it the last character in the list.
**
** Like matching rules:
** 
**      '%'       Matches any sequence of zero or more characters
**
***     '_'       Matches any one character
**
**      Ec        Where E is the "esc" character and c is any other
**                character, including '%', '_', and esc, match exactly c.
**
** The comments through this routine usually assume glob matching.
**
** This routine is usually quick, but can be N**2 in the worst case.
*/
static int patternCompare(
  const u8 *zPattern,              /* The glob pattern */
  const u8 *zString,               /* The string to compare against the glob */
  const struct compareInfo *pInfo, /* Information about how to do the compare */
  u32 esc                          /* The escape character */
){
  u32 c, c2;                       /* Next pattern and input string chars */


  u32 matchOne = pInfo->matchOne;  /* "?" or "_" */
  u32 matchAll = pInfo->matchAll;  /* "*" or "%" */

  u32 matchOther;                  /* "[" or the escape character */
  u8 noCase = pInfo->noCase;       /* True if uppercase==lowercase */
  const u8 *zEscaped = 0;          /* One past the last escaped input char */
  
  /* The GLOB operator does not have an ESCAPE clause.  And LIKE does not
  ** have the matchSet operator.  So we either have to look for one or
  ** the other, never both.  Hence the single variable matchOther is used
  ** to store the one we have to look for.
  */
  matchOther = esc ? esc : pInfo->matchSet;

  while( (c = sqlite3Utf8Read(&zPattern))!=0 ){
    if( c==matchAll ){  /* Match "*" */
      /* Skip over multiple "*" characters in the pattern.  If there
      ** are also "?" characters, skip those as well, but consume a
      ** single character of the input string for each "?" skipped */
      while( (c=sqlite3Utf8Read(&zPattern)) == matchAll
               || c == matchOne ){
        if( c==matchOne && sqlite3Utf8Read(&zString)==0 ){
          return 0;
        }
      }
      if( c==0 ){
        return 1;   /* "*" at the end of the pattern matches */
      }else if( c==matchOther ){
        if( esc ){
          c = sqlite3Utf8Read(&zPattern);
          if( c==0 ) return 0;

        }else{
          /* "[...]" immediately follows the "*".  We have to do a slow
          ** recursive search in this case, but it is an unusual case. */
          assert( matchOther<0x80 );  /* '[' is a single-byte character */
          while( *zString
                 && patternCompare(&zPattern[-1],zString,pInfo,esc)==0 ){
            SQLITE_SKIP_UTF8(zString);
          }
          return *zString!=0;
        }

      }

      /* At this point variable c contains the first character of the
      ** pattern string past the "*".  Search in the input string for the
      ** first matching character and recursively contine the match from
      ** that point.
      **
      ** For a case-insensitive search, set variable cx to be the same as
      ** c but in the other case and search the input string for either
      ** c or cx.
      */
      if( c<=0x80 ){
        u32 cx;
        if( noCase ){



          cx = sqlite3Toupper(c);
          c = sqlite3Tolower(c);

        }else{
          cx = c;
        }
        while( (c2 = *(zString++))!=0 ){
          if( c2!=c && c2!=cx ) continue;
          if( patternCompare(zPattern,zString,pInfo,esc) ) return 1;
        }
      }else{

        while( (c2 = sqlite3Utf8Read(&zString))!=0 ){
          if( c2!=c ) continue;
          if( patternCompare(zPattern,zString,pInfo,esc) ) return 1;
        }
      }
      return 0;

    }

    if( c==matchOther ){
      if( esc ){
        c = sqlite3Utf8Read(&zPattern);
        if( c==0 ) return 0;


        zEscaped = zPattern;
      }else{
        u32 prior_c = 0;

        int seen = 0;
        int invert = 0;
        c = sqlite3Utf8Read(&zString);
        if( c==0 ) return 0;
        c2 = sqlite3Utf8Read(&zPattern);
        if( c2=='^' ){
          invert = 1;
          c2 = sqlite3Utf8Read(&zPattern);
        }
        if( c2==']' ){
          if( c==']' ) seen = 1;
          c2 = sqlite3Utf8Read(&zPattern);
        }
        while( c2 && c2!=']' ){
          if( c2=='-' && zPattern[0]!=']' && zPattern[0]!=0 && prior_c>0 ){
            c2 = sqlite3Utf8Read(&zPattern);
            if( c>=prior_c && c<=c2 ) seen = 1;
            prior_c = 0;
          }else{
            if( c==c2 ){
              seen = 1;
            }
            prior_c = c2;
          }
          c2 = sqlite3Utf8Read(&zPattern);
        }
        if( c2==0 || (seen ^ invert)==0 ){
          return 0;
        }







        continue;
      }


    }

    c2 = sqlite3Utf8Read(&zString);
    if( c==c2 ) continue;
    if( noCase && c<0x80 && c2<0x80 && sqlite3Tolower(c)==sqlite3Tolower(c2) ){
      continue;
    }
    if( c==matchOne && zPattern!=zEscaped && c2!=0 ) continue;
    return 0;
  }
  return *zString==0;
}

/*
** The sqlite3_strglob() interface.
*/

  0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40,  /* e0..e7    ........ */
  0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40,  /* e8..ef    ........ */
  0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40,  /* f0..f7    ........ */
  0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40   /* f8..ff    ........ */
};
#endif








#ifndef SQLITE_USE_URI
# define  SQLITE_USE_URI 0
#endif

#ifndef SQLITE_ALLOW_COVERING_INDEX_SCAN
# define SQLITE_ALLOW_COVERING_INDEX_SCAN 1
#endif

  0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40,  /* e0..e7    ........ */
  0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40,  /* e8..ef    ........ */
  0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40,  /* f0..f7    ........ */
  0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40   /* f8..ff    ........ */
};
#endif

/* EVIDENCE-OF: R-02982-34736 In order to maintain full backwards
** compatibility for legacy applications, the URI filename capability is
** disabled by default.
**
** EVIDENCE-OF: R-38799-08373 URI filenames can be enabled or disabled
** using the SQLITE_USE_URI=1 or SQLITE_USE_URI=0 compile-time options.
*/
#ifndef SQLITE_USE_URI
# define  SQLITE_USE_URI 0
#endif

#ifndef SQLITE_ALLOW_COVERING_INDEX_SCAN
# define SQLITE_ALLOW_COVERING_INDEX_SCAN 1
#endif

/*
** Return a pointer to the column affinity string associated with index
** pIdx. A column affinity string has one character for each column in 
** the table, according to the affinity of the column:
**
**  Character      Column affinity
**  ------------------------------
**  'a'            TEXT
**  'b'            NONE
**  'c'            NUMERIC
**  'd'            INTEGER
**  'e'            REAL
**
** An extra 'd' is appended to the end of the string to cover the
** rowid that appears as the last column in every index.
**
** Memory for the buffer containing the column index affinity string
** is managed along with the rest of the Index structure. It will be
** released when sqlite3DeleteIndex() is called.
*/
const char *sqlite3IndexAffinityStr(Vdbe *v, Index *pIdx){
................................................................................
** then just set the P4 operand of the previous opcode (which should  be
** an OP_MakeRecord) to the affinity string.
**
** A column affinity string has one character per column:
**
**  Character      Column affinity
**  ------------------------------
**  'a'            TEXT
**  'b'            NONE
**  'c'            NUMERIC
**  'd'            INTEGER
**  'e'            REAL
*/
void sqlite3TableAffinity(Vdbe *v, Table *pTab, int iReg){
  int i;
  char *zColAff = pTab->zColAff;
  if( zColAff==0 ){
    sqlite3 *db = sqlite3VdbeDb(v);
    zColAff = (char *)sqlite3DbMallocRaw(0, pTab->nCol+1);

/*
** Return a pointer to the column affinity string associated with index
** pIdx. A column affinity string has one character for each column in 
** the table, according to the affinity of the column:
**
**  Character      Column affinity
**  ------------------------------
**  'A'            NONE
**  'B'            TEXT
**  'C'            NUMERIC
**  'D'            INTEGER
**  'F'            REAL
**
** An extra 'D' is appended to the end of the string to cover the
** rowid that appears as the last column in every index.
**
** Memory for the buffer containing the column index affinity string
** is managed along with the rest of the Index structure. It will be
** released when sqlite3DeleteIndex() is called.
*/
const char *sqlite3IndexAffinityStr(Vdbe *v, Index *pIdx){
................................................................................
** then just set the P4 operand of the previous opcode (which should  be
** an OP_MakeRecord) to the affinity string.
**
** A column affinity string has one character per column:
**
**  Character      Column affinity
**  ------------------------------
**  'A'            NONE
**  'B'            TEXT
**  'C'            NUMERIC
**  'D'            INTEGER
**  'E'            REAL
*/
void sqlite3TableAffinity(Vdbe *v, Table *pTab, int iReg){
  int i;
  char *zColAff = pTab->zColAff;
  if( zColAff==0 ){
    sqlite3 *db = sqlite3VdbeDb(v);
    zColAff = (char *)sqlite3DbMallocRaw(0, pTab->nCol+1);

      */
      typedef void(*LOGFUNC_t)(void*,int,const char*);
      sqlite3GlobalConfig.xLog = va_arg(ap, LOGFUNC_t);
      sqlite3GlobalConfig.pLogArg = va_arg(ap, void*);
      break;
    }






    case SQLITE_CONFIG_URI: {
      sqlite3GlobalConfig.bOpenUri = va_arg(ap, int);
      break;
    }

    case SQLITE_CONFIG_COVERING_INDEX_SCAN: {
      sqlite3GlobalConfig.bUseCis = va_arg(ap, int);
................................................................................
  char *zFile;
  char c;
  int nUri = sqlite3Strlen30(zUri);

  assert( *pzErrMsg==0 );

  if( ((flags & SQLITE_OPEN_URI) || sqlite3GlobalConfig.bOpenUri) 
   && nUri>=5 && memcmp(zUri, "file:", 5)==0 
  ){
    char *zOpt;
    int eState;                   /* Parser state when parsing URI */
    int iIn;                      /* Input character index */
    int iOut = 0;                 /* Output character index */
    int nByte = nUri+2;           /* Bytes of space to allocate */

................................................................................
  */
  assert( SQLITE_OPEN_READONLY  == 0x01 );
  assert( SQLITE_OPEN_READWRITE == 0x02 );
  assert( SQLITE_OPEN_CREATE    == 0x04 );
  testcase( (1<<(flags&7))==0x02 ); /* READONLY */
  testcase( (1<<(flags&7))==0x04 ); /* READWRITE */
  testcase( (1<<(flags&7))==0x40 ); /* READWRITE | CREATE */
  if( ((1<<(flags&7)) & 0x46)==0 ) return SQLITE_MISUSE_BKPT;



  if( sqlite3GlobalConfig.bCoreMutex==0 ){
    isThreadsafe = 0;
  }else if( flags & SQLITE_OPEN_NOMUTEX ){
    isThreadsafe = 0;
  }else if( flags & SQLITE_OPEN_FULLMUTEX ){
    isThreadsafe = 1;
................................................................................
    ** undo this setting.
    */
    case SQLITE_TESTCTRL_LOCALTIME_FAULT: {
      sqlite3GlobalConfig.bLocaltimeFault = va_arg(ap, int);
      break;
    }

#if defined(SQLITE_ENABLE_TREE_EXPLAIN)
    /*   sqlite3_test_control(SQLITE_TESTCTRL_EXPLAIN_STMT,
    **                        sqlite3_stmt*,const char**);
    **
    ** If compiled with SQLITE_ENABLE_TREE_EXPLAIN, each sqlite3_stmt holds
    ** a string that describes the optimized parse tree.  This test-control
    ** returns a pointer to that string.
    */
    case SQLITE_TESTCTRL_EXPLAIN_STMT: {
      sqlite3_stmt *pStmt = va_arg(ap, sqlite3_stmt*);
      const char **pzRet = va_arg(ap, const char**);
      *pzRet = sqlite3VdbeExplanation((Vdbe*)pStmt);
      break;
    }
#endif

    /*   sqlite3_test_control(SQLITE_TESTCTRL_NEVER_CORRUPT, int);
    **
    ** Set or clear a flag that indicates that the database file is always well-
    ** formed and never corrupt.  This flag is clear by default, indicating that
    ** database files might have arbitrary corruption.  Setting the flag during
    ** testing causes certain assert() statements in the code to be activated
    ** that demonstrat invariants on well-formed database files.

      */
      typedef void(*LOGFUNC_t)(void*,int,const char*);
      sqlite3GlobalConfig.xLog = va_arg(ap, LOGFUNC_t);
      sqlite3GlobalConfig.pLogArg = va_arg(ap, void*);
      break;
    }

    /* EVIDENCE-OF: R-55548-33817 The compile-time setting for URI filenames
    ** can be changed at start-time using the
    ** sqlite3_config(SQLITE_CONFIG_URI,1) or
    ** sqlite3_config(SQLITE_CONFIG_URI,0) configuration calls.
    */
    case SQLITE_CONFIG_URI: {
      sqlite3GlobalConfig.bOpenUri = va_arg(ap, int);
      break;
    }

    case SQLITE_CONFIG_COVERING_INDEX_SCAN: {
      sqlite3GlobalConfig.bUseCis = va_arg(ap, int);
................................................................................
  char *zFile;
  char c;
  int nUri = sqlite3Strlen30(zUri);

  assert( *pzErrMsg==0 );

  if( ((flags & SQLITE_OPEN_URI) || sqlite3GlobalConfig.bOpenUri) 
   && nUri>=5 && memcmp(zUri, "file:", 5)==0 /* IMP: R-57884-37496 */
  ){
    char *zOpt;
    int eState;                   /* Parser state when parsing URI */
    int iIn;                      /* Input character index */
    int iOut = 0;                 /* Output character index */
    int nByte = nUri+2;           /* Bytes of space to allocate */

................................................................................
  */
  assert( SQLITE_OPEN_READONLY  == 0x01 );
  assert( SQLITE_OPEN_READWRITE == 0x02 );
  assert( SQLITE_OPEN_CREATE    == 0x04 );
  testcase( (1<<(flags&7))==0x02 ); /* READONLY */
  testcase( (1<<(flags&7))==0x04 ); /* READWRITE */
  testcase( (1<<(flags&7))==0x40 ); /* READWRITE | CREATE */
  if( ((1<<(flags&7)) & 0x46)==0 ){
    return SQLITE_MISUSE_BKPT;  /* IMP: R-65497-44594 */
  }

  if( sqlite3GlobalConfig.bCoreMutex==0 ){
    isThreadsafe = 0;
  }else if( flags & SQLITE_OPEN_NOMUTEX ){
    isThreadsafe = 0;
  }else if( flags & SQLITE_OPEN_FULLMUTEX ){
    isThreadsafe = 1;
................................................................................
    ** undo this setting.
    */
    case SQLITE_TESTCTRL_LOCALTIME_FAULT: {
      sqlite3GlobalConfig.bLocaltimeFault = va_arg(ap, int);
      break;
    }

















    /*   sqlite3_test_control(SQLITE_TESTCTRL_NEVER_CORRUPT, int);
    **
    ** Set or clear a flag that indicates that the database file is always well-
    ** formed and never corrupt.  This flag is clear by default, indicating that
    ** database files might have arbitrary corruption.  Setting the flag during
    ** testing causes certain assert() statements in the code to be activated
    ** that demonstrat invariants on well-formed database files.

  }else if( sqlite3GlobalConfig.bMemstat ){
    sqlite3_mutex_enter(mem0.mutex);
    mallocWithAlarm((int)n, &p);
    sqlite3_mutex_leave(mem0.mutex);
  }else{
    p = sqlite3GlobalConfig.m.xMalloc((int)n);
  }
  assert( EIGHT_BYTE_ALIGNMENT(p) );  /* IMP: R-04675-44850 */
  return p;
}

/*
** This version of the memory allocation is for use by the application.
** First make sure the memory subsystem is initialized, then do the
** allocation.
................................................................................

/*
** Return the size of a memory allocation previously obtained from
** sqlite3Malloc() or sqlite3_malloc().
*/
int sqlite3MallocSize(void *p){
  assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
  assert( sqlite3MemdebugNoType(p, MEMTYPE_DB) );
  return sqlite3GlobalConfig.m.xSize(p);
}
int sqlite3DbMallocSize(sqlite3 *db, void *p){
  assert( db!=0 );




  assert( sqlite3_mutex_held(db->mutex) );
  if( isLookaside(db, p) ){
    return db->lookaside.sz;
  }else{
    assert( sqlite3MemdebugHasType(p, MEMTYPE_DB) );
    assert( sqlite3MemdebugHasType(p, MEMTYPE_LOOKASIDE|MEMTYPE_HEAP) );
    assert( db!=0 || sqlite3MemdebugNoType(p, MEMTYPE_LOOKASIDE) );
    return sqlite3GlobalConfig.m.xSize(p);

  }
}
sqlite3_uint64 sqlite3_msize(void *p){


  return (sqlite3_uint64)sqlite3GlobalConfig.m.xSize(p);
}

/*
** Free memory previously obtained from sqlite3Malloc().
*/
void sqlite3_free(void *p){
  if( p==0 ) return;  /* IMP: R-49053-54554 */
  assert( sqlite3MemdebugNoType(p, MEMTYPE_DB) );
  assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );

  if( sqlite3GlobalConfig.bMemstat ){
    sqlite3_mutex_enter(mem0.mutex);
    sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, -sqlite3MallocSize(p));
    sqlite3StatusAdd(SQLITE_STATUS_MALLOC_COUNT, -1);
    sqlite3GlobalConfig.m.xFree(p);
    sqlite3_mutex_leave(mem0.mutex);
  }else{
................................................................................
#endif
      pBuf->pNext = db->lookaside.pFree;
      db->lookaside.pFree = pBuf;
      db->lookaside.nOut--;
      return;
    }
  }
  assert( sqlite3MemdebugHasType(p, MEMTYPE_DB) );
  assert( sqlite3MemdebugHasType(p, MEMTYPE_LOOKASIDE|MEMTYPE_HEAP) );
  assert( db!=0 || sqlite3MemdebugNoType(p, MEMTYPE_LOOKASIDE) );
  sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
  sqlite3_free(p);
}

/*
** Change the size of an existing memory allocation
*/
void *sqlite3Realloc(void *pOld, u64 nBytes){
  int nOld, nNew, nDiff;
  void *pNew;


  if( pOld==0 ){
    return sqlite3Malloc(nBytes); /* IMP: R-28354-25769 */
  }
  if( nBytes==0 ){
    sqlite3_free(pOld); /* IMP: R-31593-10574 */
    return 0;
  }
  if( nBytes>=0x7fffff00 ){
    /* The 0x7ffff00 limit term is explained in comments on sqlite3Malloc() */
    return 0;
  }
  nOld = sqlite3MallocSize(pOld);
................................................................................
    sqlite3_mutex_enter(mem0.mutex);
    sqlite3StatusSet(SQLITE_STATUS_MALLOC_SIZE, (int)nBytes);
    nDiff = nNew - nOld;
    if( sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED) >= 
          mem0.alarmThreshold-nDiff ){
      sqlite3MallocAlarm(nDiff);
    }
    assert( sqlite3MemdebugHasType(pOld, MEMTYPE_HEAP) );
    assert( sqlite3MemdebugNoType(pOld, ~MEMTYPE_HEAP) );
    pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
    if( pNew==0 && mem0.alarmCallback ){
      sqlite3MallocAlarm((int)nBytes);
      pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
    }
    if( pNew ){
      nNew = sqlite3MallocSize(pNew);
      sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, nNew-nOld);
    }
    sqlite3_mutex_leave(mem0.mutex);
  }else{
    pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
  }
  assert( EIGHT_BYTE_ALIGNMENT(pNew) ); /* IMP: R-04675-44850 */
  return pNew;
}

/*
** The public interface to sqlite3Realloc.  Make sure that the memory
** subsystem is initialized prior to invoking sqliteRealloc.
*/
void *sqlite3_realloc(void *pOld, int n){
#ifndef SQLITE_OMIT_AUTOINIT
  if( sqlite3_initialize() ) return 0;
#endif
  if( n<0 ) n = 0;
  return sqlite3Realloc(pOld, n);
}
void *sqlite3_realloc64(void *pOld, sqlite3_uint64 n){
#ifndef SQLITE_OMIT_AUTOINIT
  if( sqlite3_initialize() ) return 0;
#endif
  return sqlite3Realloc(pOld, n);
................................................................................
    return 0;
  }
#endif
  p = sqlite3Malloc(n);
  if( !p && db ){
    db->mallocFailed = 1;
  }
  sqlite3MemdebugSetType(p, MEMTYPE_DB |
         ((db && db->lookaside.bEnabled) ? MEMTYPE_LOOKASIDE : MEMTYPE_HEAP));
  return p;
}

/*
** Resize the block of memory pointed to by p to n bytes. If the
** resize fails, set the mallocFailed flag in the connection object.
*/
................................................................................
      }
      pNew = sqlite3DbMallocRaw(db, n);
      if( pNew ){
        memcpy(pNew, p, db->lookaside.sz);
        sqlite3DbFree(db, p);
      }
    }else{
      assert( sqlite3MemdebugHasType(p, MEMTYPE_DB) );
      assert( sqlite3MemdebugHasType(p, MEMTYPE_LOOKASIDE|MEMTYPE_HEAP) );
      sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
      pNew = sqlite3_realloc64(p, n);
      if( !pNew ){
        sqlite3MemdebugSetType(p, MEMTYPE_DB|MEMTYPE_HEAP);
        db->mallocFailed = 1;
      }
      sqlite3MemdebugSetType(pNew, MEMTYPE_DB | 
            (db->lookaside.bEnabled ? MEMTYPE_LOOKASIDE : MEMTYPE_HEAP));
    }
  }
  return pNew;
}

/*

  }else if( sqlite3GlobalConfig.bMemstat ){
    sqlite3_mutex_enter(mem0.mutex);
    mallocWithAlarm((int)n, &p);
    sqlite3_mutex_leave(mem0.mutex);
  }else{
    p = sqlite3GlobalConfig.m.xMalloc((int)n);
  }
  assert( EIGHT_BYTE_ALIGNMENT(p) );  /* IMP: R-11148-40995 */
  return p;
}

/*
** This version of the memory allocation is for use by the application.
** First make sure the memory subsystem is initialized, then do the
** allocation.
................................................................................

/*
** Return the size of a memory allocation previously obtained from
** sqlite3Malloc() or sqlite3_malloc().
*/
int sqlite3MallocSize(void *p){
  assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );

  return sqlite3GlobalConfig.m.xSize(p);
}
int sqlite3DbMallocSize(sqlite3 *db, void *p){
  if( db==0 ){
    assert( sqlite3MemdebugNoType(p, ~MEMTYPE_HEAP) );
    assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
    return sqlite3MallocSize(p);
  }else{
    assert( sqlite3_mutex_held(db->mutex) );
    if( isLookaside(db, p) ){
      return db->lookaside.sz;
    }else{
      assert( sqlite3MemdebugHasType(p, (MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );
      assert( sqlite3MemdebugNoType(p, ~(MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );

      return sqlite3GlobalConfig.m.xSize(p);
    }
  }
}
sqlite3_uint64 sqlite3_msize(void *p){
  assert( sqlite3MemdebugNoType(p, ~MEMTYPE_HEAP) );
  assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
  return (sqlite3_uint64)sqlite3GlobalConfig.m.xSize(p);
}

/*
** Free memory previously obtained from sqlite3Malloc().
*/
void sqlite3_free(void *p){
  if( p==0 ) return;  /* IMP: R-49053-54554 */

  assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
  assert( sqlite3MemdebugNoType(p, ~MEMTYPE_HEAP) );
  if( sqlite3GlobalConfig.bMemstat ){
    sqlite3_mutex_enter(mem0.mutex);
    sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, -sqlite3MallocSize(p));
    sqlite3StatusAdd(SQLITE_STATUS_MALLOC_COUNT, -1);
    sqlite3GlobalConfig.m.xFree(p);
    sqlite3_mutex_leave(mem0.mutex);
  }else{
................................................................................
#endif
      pBuf->pNext = db->lookaside.pFree;
      db->lookaside.pFree = pBuf;
      db->lookaside.nOut--;
      return;
    }
  }
  assert( sqlite3MemdebugHasType(p, (MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );
  assert( sqlite3MemdebugNoType(p, ~(MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );
  assert( db!=0 || sqlite3MemdebugNoType(p, MEMTYPE_LOOKASIDE) );
  sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
  sqlite3_free(p);
}

/*
** Change the size of an existing memory allocation
*/
void *sqlite3Realloc(void *pOld, u64 nBytes){
  int nOld, nNew, nDiff;
  void *pNew;
  assert( sqlite3MemdebugHasType(pOld, MEMTYPE_HEAP) );
  assert( sqlite3MemdebugNoType(pOld, ~MEMTYPE_HEAP) );
  if( pOld==0 ){
    return sqlite3Malloc(nBytes); /* IMP: R-04300-56712 */
  }
  if( nBytes==0 ){
    sqlite3_free(pOld); /* IMP: R-26507-47431 */
    return 0;
  }
  if( nBytes>=0x7fffff00 ){
    /* The 0x7ffff00 limit term is explained in comments on sqlite3Malloc() */
    return 0;
  }
  nOld = sqlite3MallocSize(pOld);
................................................................................
    sqlite3_mutex_enter(mem0.mutex);
    sqlite3StatusSet(SQLITE_STATUS_MALLOC_SIZE, (int)nBytes);
    nDiff = nNew - nOld;
    if( sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED) >= 
          mem0.alarmThreshold-nDiff ){
      sqlite3MallocAlarm(nDiff);
    }


    pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
    if( pNew==0 && mem0.alarmCallback ){
      sqlite3MallocAlarm((int)nBytes);
      pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
    }
    if( pNew ){
      nNew = sqlite3MallocSize(pNew);
      sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, nNew-nOld);
    }
    sqlite3_mutex_leave(mem0.mutex);
  }else{
    pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
  }
  assert( EIGHT_BYTE_ALIGNMENT(pNew) ); /* IMP: R-11148-40995 */
  return pNew;
}

/*
** The public interface to sqlite3Realloc.  Make sure that the memory
** subsystem is initialized prior to invoking sqliteRealloc.
*/
void *sqlite3_realloc(void *pOld, int n){
#ifndef SQLITE_OMIT_AUTOINIT
  if( sqlite3_initialize() ) return 0;
#endif
  if( n<0 ) n = 0;  /* IMP: R-26507-47431 */
  return sqlite3Realloc(pOld, n);
}
void *sqlite3_realloc64(void *pOld, sqlite3_uint64 n){
#ifndef SQLITE_OMIT_AUTOINIT
  if( sqlite3_initialize() ) return 0;
#endif
  return sqlite3Realloc(pOld, n);
................................................................................
    return 0;
  }
#endif
  p = sqlite3Malloc(n);
  if( !p && db ){
    db->mallocFailed = 1;
  }
  sqlite3MemdebugSetType(p, 
         (db && db->lookaside.bEnabled) ? MEMTYPE_LOOKASIDE : MEMTYPE_HEAP);
  return p;
}

/*
** Resize the block of memory pointed to by p to n bytes. If the
** resize fails, set the mallocFailed flag in the connection object.
*/
................................................................................
      }
      pNew = sqlite3DbMallocRaw(db, n);
      if( pNew ){
        memcpy(pNew, p, db->lookaside.sz);
        sqlite3DbFree(db, p);
      }
    }else{
      assert( sqlite3MemdebugHasType(p, (MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );
      assert( sqlite3MemdebugNoType(p, ~(MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );
      sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
      pNew = sqlite3_realloc64(p, n);
      if( !pNew ){

        db->mallocFailed = 1;
      }
      sqlite3MemdebugSetType(pNew,
            (db->lookaside.bEnabled ? MEMTYPE_LOOKASIDE : MEMTYPE_HEAP));
    }
  }
  return pNew;
}

/*

/*
** Return TRUE if the mask of type in eType matches the type of the
** allocation p.  Also return true if p==NULL.
**
** This routine is designed for use within an assert() statement, to
** verify the type of an allocation.  For example:
**
**     assert( sqlite3MemdebugHasType(p, MEMTYPE_DB) );
*/
int sqlite3MemdebugHasType(void *p, u8 eType){
  int rc = 1;
  if( p && sqlite3GlobalConfig.m.xMalloc==sqlite3MemMalloc ){
    struct MemBlockHdr *pHdr;
    pHdr = sqlite3MemsysGetHeader(p);
    assert( pHdr->iForeGuard==FOREGUARD );         /* Allocation is valid */
................................................................................
/*
** Return TRUE if the mask of type in eType matches no bits of the type of the
** allocation p.  Also return true if p==NULL.
**
** This routine is designed for use within an assert() statement, to
** verify the type of an allocation.  For example:
**
**     assert( sqlite3MemdebugNoType(p, MEMTYPE_DB) );
*/
int sqlite3MemdebugNoType(void *p, u8 eType){
  int rc = 1;
  if( p && sqlite3GlobalConfig.m.xMalloc==sqlite3MemMalloc ){
    struct MemBlockHdr *pHdr;
    pHdr = sqlite3MemsysGetHeader(p);
    assert( pHdr->iForeGuard==FOREGUARD );         /* Allocation is valid */

/*
** Return TRUE if the mask of type in eType matches the type of the
** allocation p.  Also return true if p==NULL.
**
** This routine is designed for use within an assert() statement, to
** verify the type of an allocation.  For example:
**
**     assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
*/
int sqlite3MemdebugHasType(void *p, u8 eType){
  int rc = 1;
  if( p && sqlite3GlobalConfig.m.xMalloc==sqlite3MemMalloc ){
    struct MemBlockHdr *pHdr;
    pHdr = sqlite3MemsysGetHeader(p);
    assert( pHdr->iForeGuard==FOREGUARD );         /* Allocation is valid */
................................................................................
/*
** Return TRUE if the mask of type in eType matches no bits of the type of the
** allocation p.  Also return true if p==NULL.
**
** This routine is designed for use within an assert() statement, to
** verify the type of an allocation.  For example:
**
**     assert( sqlite3MemdebugNoType(p, MEMTYPE_LOOKASIDE) );
*/
int sqlite3MemdebugNoType(void *p, u8 eType){
  int rc = 1;
  if( p && sqlite3GlobalConfig.m.xMalloc==sqlite3MemMalloc ){
    struct MemBlockHdr *pHdr;
    pHdr = sqlite3MemsysGetHeader(p);
    assert( pHdr->iForeGuard==FOREGUARD );         /* Allocation is valid */

**
**   *  A constant sqlite3_io_methods object call METHOD that has locking
**      methods CLOSE, LOCK, UNLOCK, CKRESLOCK.
**
**   *  An I/O method finder function called FINDER that returns a pointer
**      to the METHOD object in the previous bullet.
*/
#define IOMETHODS(FINDER, METHOD, VERSION, CLOSE, LOCK, UNLOCK, CKLOCK)      \
static const sqlite3_io_methods METHOD = {                                   \
   VERSION,                    /* iVersion */                                \
   CLOSE,                      /* xClose */                                  \
   unixRead,                   /* xRead */                                   \
   unixWrite,                  /* xWrite */                                  \
   unixTruncate,               /* xTruncate */                               \
   unixSync,                   /* xSync */                                   \
................................................................................
   unixFileSize,               /* xFileSize */                               \
   LOCK,                       /* xLock */                                   \
   UNLOCK,                     /* xUnlock */                                 \
   CKLOCK,                     /* xCheckReservedLock */                      \
   unixFileControl,            /* xFileControl */                            \
   unixSectorSize,             /* xSectorSize */                             \
   unixDeviceCharacteristics,  /* xDeviceCapabilities */                     \
   unixShmMap,                 /* xShmMap */                                 \
   unixShmLock,                /* xShmLock */                                \
   unixShmBarrier,             /* xShmBarrier */                             \
   unixShmUnmap,               /* xShmUnmap */                               \
   unixFetch,                  /* xFetch */                                  \
   unixUnfetch,                /* xUnfetch */                                \
};                                                                           \
static const sqlite3_io_methods *FINDER##Impl(const char *z, unixFile *p){   \
................................................................................
IOMETHODS(
  posixIoFinder,            /* Finder function name */
  posixIoMethods,           /* sqlite3_io_methods object name */
  3,                        /* shared memory and mmap are enabled */
  unixClose,                /* xClose method */
  unixLock,                 /* xLock method */
  unixUnlock,               /* xUnlock method */
  unixCheckReservedLock     /* xCheckReservedLock method */

)
IOMETHODS(
  nolockIoFinder,           /* Finder function name */
  nolockIoMethods,          /* sqlite3_io_methods object name */
  1,                        /* shared memory is disabled */
  nolockClose,              /* xClose method */
  nolockLock,               /* xLock method */
  nolockUnlock,             /* xUnlock method */
  nolockCheckReservedLock   /* xCheckReservedLock method */

)
IOMETHODS(
  dotlockIoFinder,          /* Finder function name */
  dotlockIoMethods,         /* sqlite3_io_methods object name */
  1,                        /* shared memory is disabled */
  dotlockClose,             /* xClose method */
  dotlockLock,              /* xLock method */
  dotlockUnlock,            /* xUnlock method */
  dotlockCheckReservedLock  /* xCheckReservedLock method */

)

#if SQLITE_ENABLE_LOCKING_STYLE && !OS_VXWORKS
IOMETHODS(
  flockIoFinder,            /* Finder function name */
  flockIoMethods,           /* sqlite3_io_methods object name */
  1,                        /* shared memory is disabled */
  flockClose,               /* xClose method */
  flockLock,                /* xLock method */
  flockUnlock,              /* xUnlock method */
  flockCheckReservedLock    /* xCheckReservedLock method */

)
#endif

#if OS_VXWORKS
IOMETHODS(
  semIoFinder,              /* Finder function name */
  semIoMethods,             /* sqlite3_io_methods object name */
  1,                        /* shared memory is disabled */
  semClose,                 /* xClose method */
  semLock,                  /* xLock method */
  semUnlock,                /* xUnlock method */
  semCheckReservedLock      /* xCheckReservedLock method */

)
#endif

#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
IOMETHODS(
  afpIoFinder,              /* Finder function name */
  afpIoMethods,             /* sqlite3_io_methods object name */
  1,                        /* shared memory is disabled */
  afpClose,                 /* xClose method */
  afpLock,                  /* xLock method */
  afpUnlock,                /* xUnlock method */
  afpCheckReservedLock      /* xCheckReservedLock method */

)
#endif

/*
** The proxy locking method is a "super-method" in the sense that it
** opens secondary file descriptors for the conch and lock files and
** it uses proxy, dot-file, AFP, and flock() locking methods on those
................................................................................
IOMETHODS(
  proxyIoFinder,            /* Finder function name */
  proxyIoMethods,           /* sqlite3_io_methods object name */
  1,                        /* shared memory is disabled */
  proxyClose,               /* xClose method */
  proxyLock,                /* xLock method */
  proxyUnlock,              /* xUnlock method */
  proxyCheckReservedLock    /* xCheckReservedLock method */

)
#endif

/* nfs lockd on OSX 10.3+ doesn't clear write locks when a read lock is set */
#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
IOMETHODS(
  nfsIoFinder,               /* Finder function name */
  nfsIoMethods,              /* sqlite3_io_methods object name */
  1,                         /* shared memory is disabled */
  unixClose,                 /* xClose method */
  unixLock,                  /* xLock method */
  nfsUnlock,                 /* xUnlock method */
  unixCheckReservedLock      /* xCheckReservedLock method */

)
#endif

#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
/* 
** This "finder" function attempts to determine the best locking strategy 
** for the database file "filePath".  It then returns the sqlite3_io_methods

**
**   *  A constant sqlite3_io_methods object call METHOD that has locking
**      methods CLOSE, LOCK, UNLOCK, CKRESLOCK.
**
**   *  An I/O method finder function called FINDER that returns a pointer
**      to the METHOD object in the previous bullet.
*/
#define IOMETHODS(FINDER, METHOD, VERSION, CLOSE, LOCK, UNLOCK, CKLOCK, SHMMAP) \
static const sqlite3_io_methods METHOD = {                                   \
   VERSION,                    /* iVersion */                                \
   CLOSE,                      /* xClose */                                  \
   unixRead,                   /* xRead */                                   \
   unixWrite,                  /* xWrite */                                  \
   unixTruncate,               /* xTruncate */                               \
   unixSync,                   /* xSync */                                   \
................................................................................
   unixFileSize,               /* xFileSize */                               \
   LOCK,                       /* xLock */                                   \
   UNLOCK,                     /* xUnlock */                                 \
   CKLOCK,                     /* xCheckReservedLock */                      \
   unixFileControl,            /* xFileControl */                            \
   unixSectorSize,             /* xSectorSize */                             \
   unixDeviceCharacteristics,  /* xDeviceCapabilities */                     \
   SHMMAP,                     /* xShmMap */                                 \
   unixShmLock,                /* xShmLock */                                \
   unixShmBarrier,             /* xShmBarrier */                             \
   unixShmUnmap,               /* xShmUnmap */                               \
   unixFetch,                  /* xFetch */                                  \
   unixUnfetch,                /* xUnfetch */                                \
};                                                                           \
static const sqlite3_io_methods *FINDER##Impl(const char *z, unixFile *p){   \
................................................................................
IOMETHODS(
  posixIoFinder,            /* Finder function name */
  posixIoMethods,           /* sqlite3_io_methods object name */
  3,                        /* shared memory and mmap are enabled */
  unixClose,                /* xClose method */
  unixLock,                 /* xLock method */
  unixUnlock,               /* xUnlock method */
  unixCheckReservedLock,    /* xCheckReservedLock method */
  unixShmMap                /* xShmMap method */
)
IOMETHODS(
  nolockIoFinder,           /* Finder function name */
  nolockIoMethods,          /* sqlite3_io_methods object name */
  3,                        /* shared memory is disabled */
  nolockClose,              /* xClose method */
  nolockLock,               /* xLock method */
  nolockUnlock,             /* xUnlock method */
  nolockCheckReservedLock,  /* xCheckReservedLock method */
  0                         /* xShmMap method */
)
IOMETHODS(
  dotlockIoFinder,          /* Finder function name */
  dotlockIoMethods,         /* sqlite3_io_methods object name */
  1,                        /* shared memory is disabled */
  dotlockClose,             /* xClose method */
  dotlockLock,              /* xLock method */
  dotlockUnlock,            /* xUnlock method */
  dotlockCheckReservedLock, /* xCheckReservedLock method */
  0                         /* xShmMap method */
)

#if SQLITE_ENABLE_LOCKING_STYLE && !OS_VXWORKS
IOMETHODS(
  flockIoFinder,            /* Finder function name */
  flockIoMethods,           /* sqlite3_io_methods object name */
  1,                        /* shared memory is disabled */
  flockClose,               /* xClose method */
  flockLock,                /* xLock method */
  flockUnlock,              /* xUnlock method */
  flockCheckReservedLock,   /* xCheckReservedLock method */
  0                         /* xShmMap method */
)
#endif

#if OS_VXWORKS
IOMETHODS(
  semIoFinder,              /* Finder function name */
  semIoMethods,             /* sqlite3_io_methods object name */
  1,                        /* shared memory is disabled */
  semClose,                 /* xClose method */
  semLock,                  /* xLock method */
  semUnlock,                /* xUnlock method */
  semCheckReservedLock,     /* xCheckReservedLock method */
  0                         /* xShmMap method */
)
#endif

#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
IOMETHODS(
  afpIoFinder,              /* Finder function name */
  afpIoMethods,             /* sqlite3_io_methods object name */
  1,                        /* shared memory is disabled */
  afpClose,                 /* xClose method */
  afpLock,                  /* xLock method */
  afpUnlock,                /* xUnlock method */
  afpCheckReservedLock,     /* xCheckReservedLock method */
  0                         /* xShmMap method */
)
#endif

/*
** The proxy locking method is a "super-method" in the sense that it
** opens secondary file descriptors for the conch and lock files and
** it uses proxy, dot-file, AFP, and flock() locking methods on those
................................................................................
IOMETHODS(
  proxyIoFinder,            /* Finder function name */
  proxyIoMethods,           /* sqlite3_io_methods object name */
  1,                        /* shared memory is disabled */
  proxyClose,               /* xClose method */
  proxyLock,                /* xLock method */
  proxyUnlock,              /* xUnlock method */
  proxyCheckReservedLock,   /* xCheckReservedLock method */
  0                         /* xShmMap method */
)
#endif

/* nfs lockd on OSX 10.3+ doesn't clear write locks when a read lock is set */
#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
IOMETHODS(
  nfsIoFinder,               /* Finder function name */
  nfsIoMethods,              /* sqlite3_io_methods object name */
  1,                         /* shared memory is disabled */
  unixClose,                 /* xClose method */
  unixLock,                  /* xLock method */
  nfsUnlock,                 /* xUnlock method */
  unixCheckReservedLock,     /* xCheckReservedLock method */
  0                          /* xShmMap method */
)
#endif

#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
/* 
** This "finder" function attempts to determine the best locking strategy 
** for the database file "filePath".  It then returns the sqlite3_io_methods

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

#define osWaitForSingleObject ((DWORD(WINAPI*)(HANDLE, \
        DWORD))aSyscall[63].pCurrent)


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




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

#if SQLITE_OS_WINRT
  { "SetFilePointerEx",        (SYSCALL)SetFilePointerEx,        0 },
#else
................................................................................
  assert( sleepObj!=NULL );
  osWaitForSingleObjectEx(sleepObj, milliseconds, FALSE);
#else
  osSleep(milliseconds);
#endif
}

#if SQLITE_MAX_WORKER_THREADS>0 && !SQLITE_OS_WINRT && SQLITE_THREADSAFE>0

DWORD sqlite3Win32Wait(HANDLE hObject){
  DWORD rc;
  while( (rc = osWaitForSingleObjectEx(hObject, INFINITE,
                                       TRUE))==WAIT_IO_COMPLETION ){}
  return rc;
}
#endif

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

#define osWaitForSingleObject ((DWORD(WINAPI*)(HANDLE, \
        DWORD))aSyscall[63].pCurrent)

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

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

#if SQLITE_OS_WINRT
  { "SetFilePointerEx",        (SYSCALL)SetFilePointerEx,        0 },
#else
................................................................................
  assert( sleepObj!=NULL );
  osWaitForSingleObjectEx(sleepObj, milliseconds, FALSE);
#else
  osSleep(milliseconds);
#endif
}

#if SQLITE_MAX_WORKER_THREADS>0 && !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && \
        SQLITE_THREADSAFE>0
DWORD sqlite3Win32Wait(HANDLE hObject){
  DWORD rc;
  while( (rc = osWaitForSingleObjectEx(hObject, INFINITE,
                                       TRUE))==WAIT_IO_COMPLETION ){}
  return rc;
}
#endif

    if( rc==SQLITE_OK ){
      pNew = (char *)sqlite3PageMalloc(pageSize);
      if( !pNew ) rc = SQLITE_NOMEM;
    }

    if( rc==SQLITE_OK ){
      pager_reset(pPager);
      sqlite3PageFree(pPager->pTmpSpace);
      pPager->pTmpSpace = pNew;
      rc = sqlite3PcacheSetPageSize(pPager->pPCache, pageSize);
    }
    if( rc==SQLITE_OK ){


      pPager->dbSize = (Pgno)((nByte+pageSize-1)/pageSize);
      pPager->pageSize = pageSize;


    }
  }

  *pPageSize = pPager->pageSize;
  if( rc==SQLITE_OK ){
    if( nReserve<0 ) nReserve = pPager->nReserve;
    assert( nReserve>=0 && nReserve<1000 );

    if( rc==SQLITE_OK ){
      pNew = (char *)sqlite3PageMalloc(pageSize);
      if( !pNew ) rc = SQLITE_NOMEM;
    }

    if( rc==SQLITE_OK ){
      pager_reset(pPager);


      rc = sqlite3PcacheSetPageSize(pPager->pPCache, pageSize);
    }
    if( rc==SQLITE_OK ){
      sqlite3PageFree(pPager->pTmpSpace);
      pPager->pTmpSpace = pNew;
      pPager->dbSize = (Pgno)((nByte+pageSize-1)/pageSize);
      pPager->pageSize = pageSize;
    }else{
      sqlite3PageFree(pNew);
    }
  }

  *pPageSize = pPager->pageSize;
  if( rc==SQLITE_OK ){
    if( nReserve<0 ) nReserve = pPager->nReserve;
    assert( nReserve>=0 && nReserve<1000 );

%endif  SQLITE_OMIT_VIEW

//////////////////////// The SELECT statement /////////////////////////////////
//
cmd ::= select(X).  {
  SelectDest dest = {SRT_Output, 0, 0, 0, 0, 0};
  sqlite3Select(pParse, X, &dest);
  sqlite3ExplainBegin(pParse->pVdbe);
  sqlite3ExplainSelect(pParse->pVdbe, X);
  sqlite3ExplainFinish(pParse->pVdbe);
  sqlite3SelectDelete(pParse->db, X);
}

%type select {Select*}
%destructor select {sqlite3SelectDelete(pParse->db, $$);}
%type selectnowith {Select*}
%destructor selectnowith {sqlite3SelectDelete(pParse->db, $$);}
................................................................................
  A = pRhs;
}
%type multiselect_op {int}
multiselect_op(A) ::= UNION(OP).             {A = @OP;}
multiselect_op(A) ::= UNION ALL.             {A = TK_ALL;}
multiselect_op(A) ::= EXCEPT|INTERSECT(OP).  {A = @OP;}
%endif SQLITE_OMIT_COMPOUND_SELECT
oneselect(A) ::= SELECT distinct(D) selcollist(W) from(X) where_opt(Y)
                 groupby_opt(P) having_opt(Q) orderby_opt(Z) limit_opt(L). {
  A = sqlite3SelectNew(pParse,W,X,Y,P,Q,Z,D,L.pLimit,L.pOffset);
























}
oneselect(A) ::= values(X).    {A = X;}

%type values {Select*}
%destructor values {sqlite3SelectDelete(pParse->db, $$);}
values(A) ::= VALUES LP nexprlist(X) RP. {
  A = sqlite3SelectNew(pParse,X,0,0,0,0,0,SF_Values,0,0);
................................................................................
expr(A) ::= expr(X) NOT NULL(E). {spanUnaryPostfix(&A,pParse,TK_NOTNULL,&X,&E);}

%include {
  /* A routine to convert a binary TK_IS or TK_ISNOT expression into a
  ** unary TK_ISNULL or TK_NOTNULL expression. */
  static void binaryToUnaryIfNull(Parse *pParse, Expr *pY, Expr *pA, int op){
    sqlite3 *db = pParse->db;
    if( db->mallocFailed==0 && pY->op==TK_NULL ){
      pA->op = (u8)op;
      sqlite3ExprDelete(db, pA->pRight);
      pA->pRight = 0;
    }
  }
}

%endif  SQLITE_OMIT_VIEW

//////////////////////// The SELECT statement /////////////////////////////////
//
cmd ::= select(X).  {
  SelectDest dest = {SRT_Output, 0, 0, 0, 0, 0};
  sqlite3Select(pParse, X, &dest);



  sqlite3SelectDelete(pParse->db, X);
}

%type select {Select*}
%destructor select {sqlite3SelectDelete(pParse->db, $$);}
%type selectnowith {Select*}
%destructor selectnowith {sqlite3SelectDelete(pParse->db, $$);}
................................................................................
  A = pRhs;
}
%type multiselect_op {int}
multiselect_op(A) ::= UNION(OP).             {A = @OP;}
multiselect_op(A) ::= UNION ALL.             {A = TK_ALL;}
multiselect_op(A) ::= EXCEPT|INTERSECT(OP).  {A = @OP;}
%endif SQLITE_OMIT_COMPOUND_SELECT
oneselect(A) ::= SELECT(S) distinct(D) selcollist(W) from(X) where_opt(Y)
                 groupby_opt(P) having_opt(Q) orderby_opt(Z) limit_opt(L). {
  A = sqlite3SelectNew(pParse,W,X,Y,P,Q,Z,D,L.pLimit,L.pOffset);
#if SELECTTRACE_ENABLED
  /* Populate the Select.zSelName[] string that is used to help with
  ** query planner debugging, to differentiate between multiple Select
  ** objects in a complex query.
  **
  ** If the SELECT keyword is immediately followed by a C-style comment
  ** then extract the first few alphanumeric characters from within that
  ** comment to be the zSelName value.  Otherwise, the label is #N where
  ** is an integer that is incremented with each SELECT statement seen.
  */
  if( A!=0 ){
    const char *z = S.z+6;
    int i;
    sqlite3_snprintf(sizeof(A->zSelName), A->zSelName, "#%d",
                     ++pParse->nSelect);
    while( z[0]==' ' ) z++;
    if( z[0]=='/' && z[1]=='*' ){
      z += 2;
      while( z[0]==' ' ) z++;
      for(i=0; sqlite3Isalnum(z[i]); i++){}
      sqlite3_snprintf(sizeof(A->zSelName), A->zSelName, "%.*s", i, z);
    }
  }
#endif /* SELECTRACE_ENABLED */
}
oneselect(A) ::= values(X).    {A = X;}

%type values {Select*}
%destructor values {sqlite3SelectDelete(pParse->db, $$);}
values(A) ::= VALUES LP nexprlist(X) RP. {
  A = sqlite3SelectNew(pParse,X,0,0,0,0,0,SF_Values,0,0);
................................................................................
expr(A) ::= expr(X) NOT NULL(E). {spanUnaryPostfix(&A,pParse,TK_NOTNULL,&X,&E);}

%include {
  /* A routine to convert a binary TK_IS or TK_ISNOT expression into a
  ** unary TK_ISNULL or TK_NOTNULL expression. */
  static void binaryToUnaryIfNull(Parse *pParse, Expr *pY, Expr *pA, int op){
    sqlite3 *db = pParse->db;
    if( pY && pA && pY->op==TK_NULL ){
      pA->op = (u8)op;
      sqlite3ExprDelete(db, pA->pRight);
      pA->pRight = 0;
    }
  }
}

  assert( pCache->nPage >= pCache->nRecyclable );
  nPinned = pCache->nPage - pCache->nRecyclable;
  assert( pGroup->mxPinned == pGroup->nMaxPage + 10 - pGroup->nMinPage );
  assert( pCache->n90pct == pCache->nMax*9/10 );
  if( createFlag==1 && (
        nPinned>=pGroup->mxPinned
     || nPinned>=pCache->n90pct
     || pcache1UnderMemoryPressure(pCache)
  )){
    return 0;
  }

  if( pCache->nPage>=pCache->nHash ) pcache1ResizeHash(pCache);
  assert( pCache->nHash>0 && pCache->apHash );

  assert( pCache->nPage >= pCache->nRecyclable );
  nPinned = pCache->nPage - pCache->nRecyclable;
  assert( pGroup->mxPinned == pGroup->nMaxPage + 10 - pGroup->nMinPage );
  assert( pCache->n90pct == pCache->nMax*9/10 );
  if( createFlag==1 && (
        nPinned>=pGroup->mxPinned
     || nPinned>=pCache->n90pct
     || (pcache1UnderMemoryPressure(pCache) && pCache->nRecyclable<nPinned)
  )){
    return 0;
  }

  if( pCache->nPage>=pCache->nHash ) pcache1ResizeHash(pCache);
  assert( pCache->nHash>0 && pCache->apHash );

/*
** If the strchrnul() library function is available, then set
** HAVE_STRCHRNUL.  If that routine is not available, this module
** will supply its own.  The built-in version is slower than
** the glibc version so the glibc version is definitely preferred.
*/
#if !defined(HAVE_STRCHRNUL)
# if defined(__linux__) && defined(_GNU_SOURCE)
#  define HAVE_STRCHRNUL 1
# else
#  define HAVE_STRCHRNUL 0
# endif
#endif


................................................................................
  va_end(ap);
  sqlite3StrAccumFinish(&acc);
  fprintf(stdout,"%s", zBuf);
  fflush(stdout);
}
#endif
































































/*
** variable-argument wrapper around sqlite3VXPrintf().
*/
void sqlite3XPrintf(StrAccum *p, u32 bFlags, const char *zFormat, ...){
  va_list ap;
  va_start(ap,zFormat);
  sqlite3VXPrintf(p, bFlags, zFormat, ap);
  va_end(ap);
}

/*
** If the strchrnul() library function is available, then set
** HAVE_STRCHRNUL.  If that routine is not available, this module
** will supply its own.  The built-in version is slower than
** the glibc version so the glibc version is definitely preferred.
*/
#if !defined(HAVE_STRCHRNUL)
# if defined(linux)
#  define HAVE_STRCHRNUL 1
# else
#  define HAVE_STRCHRNUL 0
# endif
#endif


................................................................................
  va_end(ap);
  sqlite3StrAccumFinish(&acc);
  fprintf(stdout,"%s", zBuf);
  fflush(stdout);
}
#endif

#ifdef SQLITE_DEBUG
/*************************************************************************
** Routines for implementing the "TreeView" display of hierarchical
** data structures for debugging.
**
** The main entry points (coded elsewhere) are:
**     sqlite3TreeViewExpr(0, pExpr, 0);
**     sqlite3TreeViewExprList(0, pList, 0, 0);
**     sqlite3TreeViewSelect(0, pSelect, 0);
** Insert calls to those routines while debugging in order to display
** a diagram of Expr, ExprList, and Select objects.
**
*/
/* Add a new subitem to the tree.  The moreToFollow flag indicates that this
** is not the last item in the tree. */
TreeView *sqlite3TreeViewPush(TreeView *p, u8 moreToFollow){
  if( p==0 ){
    p = sqlite3_malloc( sizeof(*p) );
    if( p==0 ) return 0;
    memset(p, 0, sizeof(*p));
  }else{
    p->iLevel++;
  }
  assert( moreToFollow==0 || moreToFollow==1 );
  if( p->iLevel<sizeof(p->bLine) ) p->bLine[p->iLevel] = moreToFollow;
  return p;
}
/* Finished with one layer of the tree */
void sqlite3TreeViewPop(TreeView *p){
  if( p==0 ) return;
  p->iLevel--;
  if( p->iLevel<0 ) sqlite3_free(p);
}
/* Generate a single line of output for the tree, with a prefix that contains
** all the appropriate tree lines */
void sqlite3TreeViewLine(TreeView *p, const char *zFormat, ...){
  va_list ap;
  int i;
  StrAccum acc;
  char zBuf[500];
  sqlite3StrAccumInit(&acc, zBuf, sizeof(zBuf), 0);
  acc.useMalloc = 0;
  if( p ){
    for(i=0; i<p->iLevel && i<sizeof(p->bLine)-1; i++){
      sqlite3StrAccumAppend(&acc, p->bLine[i] ? "|   " : "    ", 4);
    }
    sqlite3StrAccumAppend(&acc, p->bLine[i] ? "|-- " : "'-- ", 4);
  }
  va_start(ap, zFormat);
  sqlite3VXPrintf(&acc, 0, zFormat, ap);
  va_end(ap);
  if( zBuf[acc.nChar-1]!='\n' ) sqlite3StrAccumAppend(&acc, "\n", 1);
  sqlite3StrAccumFinish(&acc);
  fprintf(stdout,"%s", zBuf);
  fflush(stdout);
}
/* Shorthand for starting a new tree item that consists of a single label */
void sqlite3TreeViewItem(TreeView *p, const char *zLabel, u8 moreToFollow){
  p = sqlite3TreeViewPush(p, moreToFollow);
  sqlite3TreeViewLine(p, "%s", zLabel);
}
#endif /* SQLITE_DEBUG */

/*
** variable-argument wrapper around sqlite3VXPrintf().
*/
void sqlite3XPrintf(StrAccum *p, u32 bFlags, const char *zFormat, ...){
  va_list ap;
  va_start(ap,zFormat);
  sqlite3VXPrintf(p, bFlags, zFormat, ap);
  va_end(ap);
}

**    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.
*/
#include "sqliteInt.h"















/*
** An instance of the following object is used to record information about
** how to process the DISTINCT keyword, to simplify passing that information
** into the selectInnerLoop() routine.
*/
typedef struct DistinctCtx DistinctCtx;
................................................................................
    pNew = 0;
  }else{
    assert( pNew->pSrc!=0 || pParse->nErr>0 );
  }
  assert( pNew!=&standin );
  return pNew;
}













/*
** Delete the given Select structure and all of its substructures.
*/
void sqlite3SelectDelete(sqlite3 *db, Select *p){
  if( p ){
    clearSelect(db, p);
................................................................................
  int eDest = pDest->eDest;
  int iParm = pDest->iSDParm;
  int regRow;
  int regRowid;
  int nKey;
  int iSortTab;                   /* Sorter cursor to read from */
  int nSortData;                  /* Trailing values to read from sorter */
  u8 p5;                          /* p5 parameter for 1st OP_Column */
  int i;
  int bSeq;                       /* True if sorter record includes seq. no. */
#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
  struct ExprList_item *aOutEx = p->pEList->a;
#endif

  if( pSort->labelBkOut ){
................................................................................
      addrOnce = sqlite3CodeOnce(pParse); VdbeCoverage(v);
    }
    sqlite3VdbeAddOp3(v, OP_OpenPseudo, iSortTab, regSortOut, nKey+1+nSortData);
    if( addrOnce ) sqlite3VdbeJumpHere(v, addrOnce);
    addr = 1 + sqlite3VdbeAddOp2(v, OP_SorterSort, iTab, addrBreak);
    VdbeCoverage(v);
    codeOffset(v, p->iOffset, addrContinue);
    sqlite3VdbeAddOp2(v, OP_SorterData, iTab, regSortOut);
    p5 = OPFLAG_CLEARCACHE;
    bSeq = 0;
  }else{
    addr = 1 + sqlite3VdbeAddOp2(v, OP_Sort, iTab, addrBreak); VdbeCoverage(v);
    codeOffset(v, p->iOffset, addrContinue);
    iSortTab = iTab;
    p5 = 0;
    bSeq = 1;
  }
  for(i=0; i<nSortData; i++){
    sqlite3VdbeAddOp3(v, OP_Column, iSortTab, nKey+bSeq+i, regRow+i);
    if( i==0 ) sqlite3VdbeChangeP5(v, p5);
    VdbeComment((v, "%s", aOutEx[i].zName ? aOutEx[i].zName : aOutEx[i].zSpan));
  }
  switch( eDest ){
    case SRT_Table:
    case SRT_EphemTab: {
      testcase( eDest==SRT_Table );
      testcase( eDest==SRT_EphemTab );
................................................................................
      for(ii=0; ii<p->pOrderBy->nExpr; ii++){
        if( p->pOrderBy->a[ii].u.x.iOrderByCol==0 ) return 0;
      }
    }
  }

  /***** If we reach this point, flattening is permitted. *****/



  /* Authorize the subquery */
  pParse->zAuthContext = pSubitem->zName;
  TESTONLY(i =) sqlite3AuthCheck(pParse, SQLITE_SELECT, 0, 0, 0);
  testcase( i==SQLITE_DENY );
  pParse->zAuthContext = zSavedAuthContext;

................................................................................
    Select *pPrior = p->pPrior;
    p->pOrderBy = 0;
    p->pSrc = 0;
    p->pPrior = 0;
    p->pLimit = 0;
    p->pOffset = 0;
    pNew = sqlite3SelectDup(db, p, 0);

    p->pOffset = pOffset;
    p->pLimit = pLimit;
    p->pOrderBy = pOrderBy;
    p->pSrc = pSrc;
    p->op = TK_ALL;
    if( pNew==0 ){
      p->pPrior = pPrior;
    }else{
      pNew->pPrior = pPrior;
      if( pPrior ) pPrior->pNext = pNew;
      pNew->pNext = p;
      p->pPrior = pNew;



    }
    if( db->mallocFailed ) return 1;
  }

  /* Begin flattening the iFrom-th entry of the FROM clause 
  ** in the outer query.
  */
................................................................................
    }
    substExprList(db, pParent->pEList, iParent, pSub->pEList);
    if( isAgg ){
      substExprList(db, pParent->pGroupBy, iParent, pSub->pEList);
      pParent->pHaving = substExpr(db, pParent->pHaving, iParent, pSub->pEList);
    }
    if( pSub->pOrderBy ){














      assert( pParent->pOrderBy==0 );

      pParent->pOrderBy = pSub->pOrderBy;
      pSub->pOrderBy = 0;
    }else if( pParent->pOrderBy ){
      substExprList(db, pParent->pOrderBy, iParent, pSub->pEList);
    }
    if( pSub->pWhere ){
      pWhere = sqlite3ExprDup(db, pSub->pWhere, 0);
    }else{
................................................................................
    }
  }

  /* Finially, delete what is left of the subquery and return
  ** success.
  */
  sqlite3SelectDelete(db, pSub1);








  return 1;
}
#endif /* !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW) */

/*
** Based on the contents of the AggInfo structure indicated by the first
................................................................................
      pTab->nRef++;
#if !defined(SQLITE_OMIT_VIEW) || !defined (SQLITE_OMIT_VIRTUALTABLE)
      if( pTab->pSelect || IsVirtual(pTab) ){
        /* We reach here if the named table is a really a view */
        if( sqlite3ViewGetColumnNames(pParse, pTab) ) return WRC_Abort;
        assert( pFrom->pSelect==0 );
        pFrom->pSelect = sqlite3SelectDup(db, pTab->pSelect, 0);

        sqlite3WalkSelect(pWalker, pFrom->pSelect);
      }
#endif
    }

    /* Locate the index named by the INDEXED BY clause, if any. */
    if( sqlite3IndexedByLookup(pParse, pFrom) ){
................................................................................

  db = pParse->db;
  if( p==0 || db->mallocFailed || pParse->nErr ){
    return 1;
  }
  if( sqlite3AuthCheck(pParse, SQLITE_SELECT, 0, 0, 0) ) return 1;
  memset(&sAggInfo, 0, sizeof(sAggInfo));








  assert( p->pOrderBy==0 || pDest->eDest!=SRT_DistFifo );
  assert( p->pOrderBy==0 || pDest->eDest!=SRT_Fifo );
  assert( p->pOrderBy==0 || pDest->eDest!=SRT_DistQueue );
  assert( p->pOrderBy==0 || pDest->eDest!=SRT_Queue );
  if( IgnorableOrderby(pDest) ){
    assert(pDest->eDest==SRT_Exists || pDest->eDest==SRT_Union || 
................................................................................

#ifndef SQLITE_OMIT_COMPOUND_SELECT
  /* If there is are a sequence of queries, do the earlier ones first.
  */
  if( p->pPrior ){
    rc = multiSelect(pParse, p, pDest);
    explainSetInteger(pParse->iSelectId, iRestoreSelectId);




    return rc;
  }
#endif

  /* If the query is DISTINCT with an ORDER BY but is not an aggregate, and 
  ** if the select-list is the same as the ORDER BY list, then this query
  ** can be rewritten as a GROUP BY. In other words, this:
................................................................................
      ** (b0 is memory location iBMem+0, b1 is iBMem+1, and so forth)
      ** Then compare the current GROUP BY terms against the GROUP BY terms
      ** from the previous row currently stored in a0, a1, a2...
      */
      addrTopOfLoop = sqlite3VdbeCurrentAddr(v);
      sqlite3ExprCacheClear(pParse);
      if( groupBySort ){
        sqlite3VdbeAddOp2(v, OP_SorterData, sAggInfo.sortingIdx, sortOut);
      }
      for(j=0; j<pGroupBy->nExpr; j++){
        if( groupBySort ){
          sqlite3VdbeAddOp3(v, OP_Column, sortPTab, j, iBMem+j);
          if( j==0 ) sqlite3VdbeChangeP5(v, OPFLAG_CLEARCACHE);
        }else{
          sAggInfo.directMode = 1;
          sqlite3ExprCode(pParse, pGroupBy->a[j].pExpr, iBMem+j);
        }
      }
      sqlite3VdbeAddOp4(v, OP_Compare, iAMem, iBMem, pGroupBy->nExpr,
                          (char*)sqlite3KeyInfoRef(pKeyInfo), P4_KEYINFO);
................................................................................
  */
  if( rc==SQLITE_OK && pDest->eDest==SRT_Output ){
    generateColumnNames(pParse, pTabList, pEList);
  }

  sqlite3DbFree(db, sAggInfo.aCol);
  sqlite3DbFree(db, sAggInfo.aFunc);




  return rc;
}

#if defined(SQLITE_ENABLE_TREE_EXPLAIN)
/*
** Generate a human-readable description of a the Select object.
*/
static void explainOneSelect(Vdbe *pVdbe, Select *p){
  sqlite3ExplainPrintf(pVdbe, "SELECT ");
  if( p->selFlags & (SF_Distinct|SF_Aggregate) ){

    if( p->selFlags & SF_Distinct ){
      sqlite3ExplainPrintf(pVdbe, "DISTINCT ");
    }
    if( p->selFlags & SF_Aggregate ){

      sqlite3ExplainPrintf(pVdbe, "agg_flag ");
    }

    sqlite3ExplainNL(pVdbe);
    sqlite3ExplainPrintf(pVdbe, "   ");
  }

  sqlite3ExplainExprList(pVdbe, p->pEList);
  sqlite3ExplainNL(pVdbe);


  if( p->pSrc && p->pSrc->nSrc ){
    int i;
    sqlite3ExplainPrintf(pVdbe, "FROM ");
    sqlite3ExplainPush(pVdbe);


    for(i=0; i<p->pSrc->nSrc; i++){
      struct SrcList_item *pItem = &p->pSrc->a[i];
      sqlite3ExplainPrintf(pVdbe, "{%d,*} = ", pItem->iCursor);




      if( pItem->pSelect ){
        sqlite3ExplainSelect(pVdbe, pItem->pSelect);

        if( pItem->pTab ){
          sqlite3ExplainPrintf(pVdbe, " (tabname=%s)", pItem->pTab->zName);

        }
      }else if( pItem->zName ){
        sqlite3ExplainPrintf(pVdbe, "%s", pItem->zName);

      }
      if( pItem->zAlias ){
        sqlite3ExplainPrintf(pVdbe, " (AS %s)", pItem->zAlias);
      }
      if( pItem->jointype & JT_LEFT ){
        sqlite3ExplainPrintf(pVdbe, " LEFT-JOIN");

      }
      sqlite3ExplainNL(pVdbe);




    }
    sqlite3ExplainPop(pVdbe);

  }


  if( p->pWhere ){
    sqlite3ExplainPrintf(pVdbe, "WHERE ");
    sqlite3ExplainExpr(pVdbe, p->pWhere);
    sqlite3ExplainNL(pVdbe);



  }
  if( p->pGroupBy ){
    sqlite3ExplainPrintf(pVdbe, "GROUPBY ");
    sqlite3ExplainExprList(pVdbe, p->pGroupBy);
    sqlite3ExplainNL(pVdbe);

  }
  if( p->pHaving ){
    sqlite3ExplainPrintf(pVdbe, "HAVING ");
    sqlite3ExplainExpr(pVdbe, p->pHaving);
    sqlite3ExplainNL(pVdbe);



  }
  if( p->pOrderBy ){
    sqlite3ExplainPrintf(pVdbe, "ORDERBY ");
    sqlite3ExplainExprList(pVdbe, p->pOrderBy);
    sqlite3ExplainNL(pVdbe);

  }
  if( p->pLimit ){
    sqlite3ExplainPrintf(pVdbe, "LIMIT ");
    sqlite3ExplainExpr(pVdbe, p->pLimit);
    sqlite3ExplainNL(pVdbe);



  }
  if( p->pOffset ){
    sqlite3ExplainPrintf(pVdbe, "OFFSET ");
    sqlite3ExplainExpr(pVdbe, p->pOffset);
    sqlite3ExplainNL(pVdbe);



  }
}
void sqlite3ExplainSelect(Vdbe *pVdbe, Select *p){
  if( p==0 ){
    sqlite3ExplainPrintf(pVdbe, "(null-select)");
    return;
  }
  sqlite3ExplainPush(pVdbe);
  while( p ){
    explainOneSelect(pVdbe, p);
    p = p->pNext;
    if( p==0 ) break;
    sqlite3ExplainNL(pVdbe);
    sqlite3ExplainPrintf(pVdbe, "%s\n", selectOpName(p->op));
  }

  sqlite3ExplainPrintf(pVdbe, "END");
  sqlite3ExplainPop(pVdbe);
}


/* End of the structure debug printing code
*****************************************************************************/
#endif /* defined(SQLITE_ENABLE_TREE_EXPLAIN) */

**    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.
*/
#include "sqliteInt.h"

/*
** Trace output macros
*/
#if SELECTTRACE_ENABLED
/***/ int sqlite3SelectTrace = 0;
# define SELECTTRACE(K,P,S,X)  \
  if(sqlite3SelectTrace&(K))   \
    sqlite3DebugPrintf("%*s%s.%p: ",(P)->nSelectIndent*2-2,"",(S)->zSelName,(S)),\
    sqlite3DebugPrintf X
#else
# define SELECTTRACE(K,P,S,X)
#endif


/*
** An instance of the following object is used to record information about
** how to process the DISTINCT keyword, to simplify passing that information
** into the selectInnerLoop() routine.
*/
typedef struct DistinctCtx DistinctCtx;
................................................................................
    pNew = 0;
  }else{
    assert( pNew->pSrc!=0 || pParse->nErr>0 );
  }
  assert( pNew!=&standin );
  return pNew;
}

#if SELECTTRACE_ENABLED
/*
** Set the name of a Select object
*/
void sqlite3SelectSetName(Select *p, const char *zName){
  if( p && zName ){
    sqlite3_snprintf(sizeof(p->zSelName), p->zSelName, "%s", zName);
  }
}
#endif


/*
** Delete the given Select structure and all of its substructures.
*/
void sqlite3SelectDelete(sqlite3 *db, Select *p){
  if( p ){
    clearSelect(db, p);
................................................................................
  int eDest = pDest->eDest;
  int iParm = pDest->iSDParm;
  int regRow;
  int regRowid;
  int nKey;
  int iSortTab;                   /* Sorter cursor to read from */
  int nSortData;                  /* Trailing values to read from sorter */

  int i;
  int bSeq;                       /* True if sorter record includes seq. no. */
#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
  struct ExprList_item *aOutEx = p->pEList->a;
#endif

  if( pSort->labelBkOut ){
................................................................................
      addrOnce = sqlite3CodeOnce(pParse); VdbeCoverage(v);
    }
    sqlite3VdbeAddOp3(v, OP_OpenPseudo, iSortTab, regSortOut, nKey+1+nSortData);
    if( addrOnce ) sqlite3VdbeJumpHere(v, addrOnce);
    addr = 1 + sqlite3VdbeAddOp2(v, OP_SorterSort, iTab, addrBreak);
    VdbeCoverage(v);
    codeOffset(v, p->iOffset, addrContinue);
    sqlite3VdbeAddOp3(v, OP_SorterData, iTab, regSortOut, iSortTab);

    bSeq = 0;
  }else{
    addr = 1 + sqlite3VdbeAddOp2(v, OP_Sort, iTab, addrBreak); VdbeCoverage(v);
    codeOffset(v, p->iOffset, addrContinue);
    iSortTab = iTab;

    bSeq = 1;
  }
  for(i=0; i<nSortData; i++){
    sqlite3VdbeAddOp3(v, OP_Column, iSortTab, nKey+bSeq+i, regRow+i);

    VdbeComment((v, "%s", aOutEx[i].zName ? aOutEx[i].zName : aOutEx[i].zSpan));
  }
  switch( eDest ){
    case SRT_Table:
    case SRT_EphemTab: {
      testcase( eDest==SRT_Table );
      testcase( eDest==SRT_EphemTab );
................................................................................
      for(ii=0; ii<p->pOrderBy->nExpr; ii++){
        if( p->pOrderBy->a[ii].u.x.iOrderByCol==0 ) return 0;
      }
    }
  }

  /***** If we reach this point, flattening is permitted. *****/
  SELECTTRACE(1,pParse,p,("flatten %s.%p from term %d\n",
                   pSub->zSelName, pSub, iFrom));

  /* Authorize the subquery */
  pParse->zAuthContext = pSubitem->zName;
  TESTONLY(i =) sqlite3AuthCheck(pParse, SQLITE_SELECT, 0, 0, 0);
  testcase( i==SQLITE_DENY );
  pParse->zAuthContext = zSavedAuthContext;

................................................................................
    Select *pPrior = p->pPrior;
    p->pOrderBy = 0;
    p->pSrc = 0;
    p->pPrior = 0;
    p->pLimit = 0;
    p->pOffset = 0;
    pNew = sqlite3SelectDup(db, p, 0);
    sqlite3SelectSetName(pNew, pSub->zSelName);
    p->pOffset = pOffset;
    p->pLimit = pLimit;
    p->pOrderBy = pOrderBy;
    p->pSrc = pSrc;
    p->op = TK_ALL;
    if( pNew==0 ){
      p->pPrior = pPrior;
    }else{
      pNew->pPrior = pPrior;
      if( pPrior ) pPrior->pNext = pNew;
      pNew->pNext = p;
      p->pPrior = pNew;
      SELECTTRACE(2,pParse,p,
         ("compound-subquery flattener creates %s.%p as peer\n",
         pNew->zSelName, pNew));
    }
    if( db->mallocFailed ) return 1;
  }

  /* Begin flattening the iFrom-th entry of the FROM clause 
  ** in the outer query.
  */
................................................................................
    }
    substExprList(db, pParent->pEList, iParent, pSub->pEList);
    if( isAgg ){
      substExprList(db, pParent->pGroupBy, iParent, pSub->pEList);
      pParent->pHaving = substExpr(db, pParent->pHaving, iParent, pSub->pEList);
    }
    if( pSub->pOrderBy ){
      /* At this point, any non-zero iOrderByCol values indicate that the
      ** ORDER BY column expression is identical to the iOrderByCol'th
      ** expression returned by SELECT statement pSub. Since these values
      ** do not necessarily correspond to columns in SELECT statement pParent,
      ** zero them before transfering the ORDER BY clause.
      **
      ** Not doing this may cause an error if a subsequent call to this
      ** function attempts to flatten a compound sub-query into pParent
      ** (the only way this can happen is if the compound sub-query is
      ** currently part of pSub->pSrc). See ticket [d11a6e908f].  */
      ExprList *pOrderBy = pSub->pOrderBy;
      for(i=0; i<pOrderBy->nExpr; i++){
        pOrderBy->a[i].u.x.iOrderByCol = 0;
      }
      assert( pParent->pOrderBy==0 );
      assert( pSub->pPrior==0 );
      pParent->pOrderBy = pOrderBy;
      pSub->pOrderBy = 0;
    }else if( pParent->pOrderBy ){
      substExprList(db, pParent->pOrderBy, iParent, pSub->pEList);
    }
    if( pSub->pWhere ){
      pWhere = sqlite3ExprDup(db, pSub->pWhere, 0);
    }else{
................................................................................
    }
  }

  /* Finially, delete what is left of the subquery and return
  ** success.
  */
  sqlite3SelectDelete(db, pSub1);

#if SELECTTRACE_ENABLED
  if( sqlite3SelectTrace & 0x100 ){
    sqlite3DebugPrintf("After flattening:\n");
    sqlite3TreeViewSelect(0, p, 0);
  }
#endif

  return 1;
}
#endif /* !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW) */

/*
** Based on the contents of the AggInfo structure indicated by the first
................................................................................
      pTab->nRef++;
#if !defined(SQLITE_OMIT_VIEW) || !defined (SQLITE_OMIT_VIRTUALTABLE)
      if( pTab->pSelect || IsVirtual(pTab) ){
        /* We reach here if the named table is a really a view */
        if( sqlite3ViewGetColumnNames(pParse, pTab) ) return WRC_Abort;
        assert( pFrom->pSelect==0 );
        pFrom->pSelect = sqlite3SelectDup(db, pTab->pSelect, 0);
        sqlite3SelectSetName(pFrom->pSelect, pTab->zName);
        sqlite3WalkSelect(pWalker, pFrom->pSelect);
      }
#endif
    }

    /* Locate the index named by the INDEXED BY clause, if any. */
    if( sqlite3IndexedByLookup(pParse, pFrom) ){
................................................................................

  db = pParse->db;
  if( p==0 || db->mallocFailed || pParse->nErr ){
    return 1;
  }
  if( sqlite3AuthCheck(pParse, SQLITE_SELECT, 0, 0, 0) ) return 1;
  memset(&sAggInfo, 0, sizeof(sAggInfo));
#if SELECTTRACE_ENABLED
  pParse->nSelectIndent++;
  SELECTTRACE(1,pParse,p, ("begin processing:\n"));
  if( sqlite3SelectTrace & 0x100 ){
    sqlite3TreeViewSelect(0, p, 0);
  }
#endif

  assert( p->pOrderBy==0 || pDest->eDest!=SRT_DistFifo );
  assert( p->pOrderBy==0 || pDest->eDest!=SRT_Fifo );
  assert( p->pOrderBy==0 || pDest->eDest!=SRT_DistQueue );
  assert( p->pOrderBy==0 || pDest->eDest!=SRT_Queue );
  if( IgnorableOrderby(pDest) ){
    assert(pDest->eDest==SRT_Exists || pDest->eDest==SRT_Union || 
................................................................................

#ifndef SQLITE_OMIT_COMPOUND_SELECT
  /* If there is are a sequence of queries, do the earlier ones first.
  */
  if( p->pPrior ){
    rc = multiSelect(pParse, p, pDest);
    explainSetInteger(pParse->iSelectId, iRestoreSelectId);
#if SELECTTRACE_ENABLED
    SELECTTRACE(1,pParse,p,("end compound-select processing\n"));
    pParse->nSelectIndent--;
#endif
    return rc;
  }
#endif

  /* If the query is DISTINCT with an ORDER BY but is not an aggregate, and 
  ** if the select-list is the same as the ORDER BY list, then this query
  ** can be rewritten as a GROUP BY. In other words, this:
................................................................................
      ** (b0 is memory location iBMem+0, b1 is iBMem+1, and so forth)
      ** Then compare the current GROUP BY terms against the GROUP BY terms
      ** from the previous row currently stored in a0, a1, a2...
      */
      addrTopOfLoop = sqlite3VdbeCurrentAddr(v);
      sqlite3ExprCacheClear(pParse);
      if( groupBySort ){
        sqlite3VdbeAddOp3(v, OP_SorterData, sAggInfo.sortingIdx, sortOut,sortPTab);
      }
      for(j=0; j<pGroupBy->nExpr; j++){
        if( groupBySort ){
          sqlite3VdbeAddOp3(v, OP_Column, sortPTab, j, iBMem+j);

        }else{
          sAggInfo.directMode = 1;
          sqlite3ExprCode(pParse, pGroupBy->a[j].pExpr, iBMem+j);
        }
      }
      sqlite3VdbeAddOp4(v, OP_Compare, iAMem, iBMem, pGroupBy->nExpr,
                          (char*)sqlite3KeyInfoRef(pKeyInfo), P4_KEYINFO);
................................................................................
  */
  if( rc==SQLITE_OK && pDest->eDest==SRT_Output ){
    generateColumnNames(pParse, pTabList, pEList);
  }

  sqlite3DbFree(db, sAggInfo.aCol);
  sqlite3DbFree(db, sAggInfo.aFunc);
#if SELECTTRACE_ENABLED
  SELECTTRACE(1,pParse,p,("end processing\n"));
  pParse->nSelectIndent--;
#endif
  return rc;
}

#ifdef SQLITE_DEBUG
/*
** Generate a human-readable description of a the Select object.
*/
void sqlite3TreeViewSelect(TreeView *pView, const Select *p, u8 moreToFollow){
  int n = 0;
  pView = sqlite3TreeViewPush(pView, moreToFollow);
  sqlite3TreeViewLine(pView, "SELECT%s%s",
    ((p->selFlags & SF_Distinct) ? " DISTINCT" : ""),


    ((p->selFlags & SF_Aggregate) ? " agg_flag" : "")
  );
  if( p->pSrc && p->pSrc->nSrc ) n++;

  if( p->pWhere ) n++;
  if( p->pGroupBy ) n++;
  if( p->pHaving ) n++;

  if( p->pOrderBy ) n++;
  if( p->pLimit ) n++;
  if( p->pOffset ) n++;
  if( p->pPrior ) n++;
  sqlite3TreeViewExprList(pView, p->pEList, (n--)>0, "result-set");
  if( p->pSrc && p->pSrc->nSrc ){
    int i;


    pView = sqlite3TreeViewPush(pView, (n--)>0);
    sqlite3TreeViewLine(pView, "FROM");
    for(i=0; i<p->pSrc->nSrc; i++){
      struct SrcList_item *pItem = &p->pSrc->a[i];

      StrAccum x;
      char zLine[100];
      sqlite3StrAccumInit(&x, zLine, sizeof(zLine), 0);
      sqlite3XPrintf(&x, 0, "{%d,*}", pItem->iCursor);
      if( pItem->zDatabase ){

        sqlite3XPrintf(&x, 0, " %s.%s", pItem->zDatabase, pItem->zName);
      }else if( pItem->zName ){

        sqlite3XPrintf(&x, 0, " %s", pItem->zName);
      }
      if( pItem->pTab ){

        sqlite3XPrintf(&x, 0, " tabname=%Q", pItem->pTab->zName);
      }
      if( pItem->zAlias ){
        sqlite3XPrintf(&x, 0, " (AS %s)", pItem->zAlias);
      }
      if( pItem->jointype & JT_LEFT ){

        sqlite3XPrintf(&x, 0, " LEFT-JOIN");
      }

      sqlite3StrAccumFinish(&x);
      sqlite3TreeViewItem(pView, zLine, i<p->pSrc->nSrc-1); 
      if( pItem->pSelect ){
        sqlite3TreeViewSelect(pView, pItem->pSelect, 0);
      }

      sqlite3TreeViewPop(pView);
    }
    sqlite3TreeViewPop(pView);
  }
  if( p->pWhere ){



    sqlite3TreeViewItem(pView, "WHERE", (n--)>0);
    sqlite3TreeViewExpr(pView, p->pWhere, 0);
    sqlite3TreeViewPop(pView);
  }
  if( p->pGroupBy ){



    sqlite3TreeViewExprList(pView, p->pGroupBy, (n--)>0, "GROUPBY");
  }
  if( p->pHaving ){



    sqlite3TreeViewItem(pView, "HAVING", (n--)>0);
    sqlite3TreeViewExpr(pView, p->pHaving, 0);
    sqlite3TreeViewPop(pView);
  }
  if( p->pOrderBy ){



    sqlite3TreeViewExprList(pView, p->pOrderBy, (n--)>0, "ORDERBY");
  }
  if( p->pLimit ){



    sqlite3TreeViewItem(pView, "LIMIT", (n--)>0);
    sqlite3TreeViewExpr(pView, p->pLimit, 0);
    sqlite3TreeViewPop(pView);
  }
  if( p->pOffset ){



    sqlite3TreeViewItem(pView, "OFFSET", (n--)>0);
    sqlite3TreeViewExpr(pView, p->pOffset, 0);
    sqlite3TreeViewPop(pView);
  }


  if( p->pPrior ){




    const char *zOp = "UNION";
    switch( p->op ){
      case TK_ALL:         zOp = "UNION ALL";  break;
      case TK_INTERSECT:   zOp = "INTERSECT";  break;
      case TK_EXCEPT:      zOp = "EXCEPT";     break;

    }
    sqlite3TreeViewItem(pView, zOp, (n--)>0);
    sqlite3TreeViewSelect(pView, p->pPrior, 0);
    sqlite3TreeViewPop(pView);
  }
  sqlite3TreeViewPop(pView);
}

#endif /* SQLITE_DEBUG */

#endif
      if( p->cnt++==0 && p->showHeader ){
        for(i=0; i<nArg; i++){
          output_csv(p, azCol[i] ? azCol[i] : "", i<nArg-1);
        }
        fprintf(p->out,"%s",p->newline);
      }
      if( azArg>0 ){
        for(i=0; i<nArg; i++){
          output_csv(p, azArg[i], i<nArg-1);
        }
        fprintf(p->out,"%s",p->newline);
      }
#if defined(WIN32) || defined(_WIN32)
      fflush(p->out);
................................................................................
            fprintf(pArg->out,"%s\n", sqlite3_column_text(pExplain, 3));
          }
        }
        sqlite3_finalize(pExplain);
        sqlite3_free(zEQP);
      }

      /* Output TESTCTRL_EXPLAIN text of requested */
      if( pArg && pArg->mode==MODE_Explain ){
        const char *zExplain = 0;
        sqlite3_test_control(SQLITE_TESTCTRL_EXPLAIN_STMT, pStmt, &zExplain);
        if( zExplain && zExplain[0] ){
          fprintf(pArg->out, "%s", zExplain);
        }
      }

      /* If the shell is currently in ".explain" mode, gather the extra
      ** data required to add indents to the output.*/
      if( pArg && pArg->mode==MODE_Explain ){
        explain_data_prepare(pArg, pStmt);
      }

      /* perform the first step.  this will tell us if we
................................................................................
    }else if( rc != SQLITE_OK ){
      fprintf(stderr,"Error: querying schema information\n");
      rc = 1;
    }else{
      rc = 0;
    }
  }else










#ifdef SQLITE_DEBUG
  /* Undocumented commands for internal testing.  Subject to change
  ** without notice. */
  if( c=='s' && n>=10 && strncmp(azArg[0], "selftest-", 9)==0 ){
    if( strncmp(azArg[0]+9, "boolean", n-9)==0 ){
      int i, v;
................................................................................
      if( p->echoOn ) printf("%s\n", zSql);
      nSql = 0;
    }
  }
  if( nSql ){
    if( !_all_whitespace(zSql) ){
      fprintf(stderr, "Error: incomplete SQL: %s\n", zSql);

    }
    free(zSql);
  }
  free(zLine);
  return errCnt>0;
}

#endif
      if( p->cnt++==0 && p->showHeader ){
        for(i=0; i<nArg; i++){
          output_csv(p, azCol[i] ? azCol[i] : "", i<nArg-1);
        }
        fprintf(p->out,"%s",p->newline);
      }
      if( nArg>0 ){
        for(i=0; i<nArg; i++){
          output_csv(p, azArg[i], i<nArg-1);
        }
        fprintf(p->out,"%s",p->newline);
      }
#if defined(WIN32) || defined(_WIN32)
      fflush(p->out);
................................................................................
            fprintf(pArg->out,"%s\n", sqlite3_column_text(pExplain, 3));
          }
        }
        sqlite3_finalize(pExplain);
        sqlite3_free(zEQP);
      }










      /* If the shell is currently in ".explain" mode, gather the extra
      ** data required to add indents to the output.*/
      if( pArg && pArg->mode==MODE_Explain ){
        explain_data_prepare(pArg, pStmt);
      }

      /* perform the first step.  this will tell us if we
................................................................................
    }else if( rc != SQLITE_OK ){
      fprintf(stderr,"Error: querying schema information\n");
      rc = 1;
    }else{
      rc = 0;
    }
  }else


#if defined(SQLITE_DEBUG) && defined(SQLITE_ENABLE_SELECTTRACE)
  if( c=='s' && n==11 && strncmp(azArg[0], "selecttrace", n)==0 ){
    extern int sqlite3SelectTrace;
    sqlite3SelectTrace = nArg>=2 ? booleanValue(azArg[1]) : 0xff;
  }else
#endif


#ifdef SQLITE_DEBUG
  /* Undocumented commands for internal testing.  Subject to change
  ** without notice. */
  if( c=='s' && n>=10 && strncmp(azArg[0], "selftest-", 9)==0 ){
    if( strncmp(azArg[0]+9, "boolean", n-9)==0 ){
      int i, v;
................................................................................
      if( p->echoOn ) printf("%s\n", zSql);
      nSql = 0;
    }
  }
  if( nSql ){
    if( !_all_whitespace(zSql) ){
      fprintf(stderr, "Error: incomplete SQL: %s\n", zSql);
      errCnt++;
    }
    free(zSql);
  }
  free(zLine);
  return errCnt>0;
}

** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
** object.)^ ^(If the database is opened (and/or created) successfully, then
** [SQLITE_OK] is returned.  Otherwise an [error code] is returned.)^ ^The
** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
** an English language description of the error following a failure of any
** of the sqlite3_open() routines.
**
** ^The default encoding for the database will be UTF-8 if
** sqlite3_open() or sqlite3_open_v2() is called and
** UTF-16 in the native byte order if sqlite3_open16() is used.
**
** Whether or not an error occurs when it is opened, resources
** associated with the [database connection] handle should be released by
** passing it to [sqlite3_close()] when it is no longer required.
**
** The sqlite3_open_v2() interface works like sqlite3_open()
** except that it accepts two additional parameters for additional control
................................................................................
** present, is ignored.
**
** ^SQLite uses the path component of the URI as the name of the disk file
** which contains the database. ^If the path begins with a '/' character, 
** then it is interpreted as an absolute path. ^If the path does not begin 
** with a '/' (meaning that the authority section is omitted from the URI)
** then the path is interpreted as a relative path. 
** ^On windows, the first component of an absolute path 
** is a drive specification (e.g. "C:").
**
** [[core URI query parameters]]
** The query component of a URI may contain parameters that are interpreted
** either by SQLite itself, or by a [VFS | custom VFS implementation].

** SQLite interprets the following three query parameters:
**
** <ul>
**   <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of
**     a VFS object that provides the operating system interface that should
**     be used to access the database file on disk. ^If this option is set to
**     an empty string the default VFS object is used. ^Specifying an unknown
**     VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is
................................................................................
**     SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to
**     sqlite3_open_v2(). ^Setting the cache parameter to "private" is 
**     equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
**     ^If sqlite3_open_v2() is used and the "cache" parameter is present in
**     a URI filename, its value overrides any behavior requested by setting
**     SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
**
**  <li> <b>psow</b>: ^The psow parameter may be "true" (or "on" or "yes" or
**     "1") or "false" (or "off" or "no" or "0") to indicate that the
**     [powersafe overwrite] property does or does not apply to the
**     storage media on which the database file resides.  ^The psow query
**     parameter only works for the built-in unix and Windows VFSes.
**
**  <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter
**     which if set disables file locking in rollback journal modes.  This
**     is useful for accessing a database on a filesystem that does not
**     support locking.  Caution:  Database corruption might result if two
**     or more processes write to the same database and any one of those
**     processes uses nolock=1.
................................................................................
** that parameter must be the byte offset
** where the NUL terminator would occur assuming the string were NUL
** terminated.  If any NUL characters occur at byte offsets less than 
** the value of the fourth parameter then the resulting string value will
** contain embedded NULs.  The result of expressions involving strings
** with embedded NULs is undefined.
**
** ^The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and
** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or
** string after SQLite has finished with it.  ^The destructor is called
** to dispose of the BLOB or string even if the call to sqlite3_bind_blob(),
** sqlite3_bind_text(), or sqlite3_bind_text16() fails.  
** ^If the fifth argument is
** the special value [SQLITE_STATIC], then SQLite assumes that the
** information is in static, unmanaged space and does not need to be freed.
** ^If the fifth argument has the value [SQLITE_TRANSIENT], then
** SQLite makes its own private copy of the data immediately, before
** the sqlite3_bind_*() routine returns.
**
** ^The sixth argument to sqlite3_bind_text64() must be one of
** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]
** to specify the encoding of the text in the third parameter.  If
** the sixth argument to sqlite3_bind_text64() is not how of the
** allowed values shown above, or if the text encoding is different
** from the encoding specified by the sixth parameter, then the behavior
** is undefined.
**
** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
** is filled with zeroes.  ^A zeroblob uses a fixed amount of memory
** (just an integer to hold its size) while it is being processed.
................................................................................
** of the application-defined function to be the 64-bit signed integer
** value given in the 2nd argument.
**
** ^The sqlite3_result_null() interface sets the return value
** of the application-defined function to be NULL.
**
** ^The sqlite3_result_text(), sqlite3_result_text16(),
** sqlite3_result_text16le(), and sqlite3_result_text16be()
** set the return value of the application-defined function to be
** a text string which is represented as UTF-8, UTF-16 native byte order,
** UTF-16 little endian, or UTF-16 big endian, respectively.
** ^The sqlite3_result_text64() interface sets the return value of an
** application-defined function to be a text string in an encoding
** specified by the fifth (and last) parameter, which must be one
** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE].
................................................................................
#define SQLITE_TESTCTRL_ASSERT                  12
#define SQLITE_TESTCTRL_ALWAYS                  13
#define SQLITE_TESTCTRL_RESERVE                 14
#define SQLITE_TESTCTRL_OPTIMIZATIONS           15
#define SQLITE_TESTCTRL_ISKEYWORD               16
#define SQLITE_TESTCTRL_SCRATCHMALLOC           17
#define SQLITE_TESTCTRL_LOCALTIME_FAULT         18
#define SQLITE_TESTCTRL_EXPLAIN_STMT            19
#define SQLITE_TESTCTRL_NEVER_CORRUPT           20
#define SQLITE_TESTCTRL_VDBE_COVERAGE           21
#define SQLITE_TESTCTRL_BYTEORDER               22
#define SQLITE_TESTCTRL_ISINIT                  23
#define SQLITE_TESTCTRL_SORTER_MMAP             24
#define SQLITE_TESTCTRL_LAST                    24

** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
** object.)^ ^(If the database is opened (and/or created) successfully, then
** [SQLITE_OK] is returned.  Otherwise an [error code] is returned.)^ ^The
** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
** an English language description of the error following a failure of any
** of the sqlite3_open() routines.
**
** ^The default encoding will be UTF-8 for databases created using
** sqlite3_open() or sqlite3_open_v2().  ^The default encoding for databases
** created using sqlite3_open16() will be UTF-16 in the native byte order.
**
** Whether or not an error occurs when it is opened, resources
** associated with the [database connection] handle should be released by
** passing it to [sqlite3_close()] when it is no longer required.
**
** The sqlite3_open_v2() interface works like sqlite3_open()
** except that it accepts two additional parameters for additional control
................................................................................
** present, is ignored.
**
** ^SQLite uses the path component of the URI as the name of the disk file
** which contains the database. ^If the path begins with a '/' character, 
** then it is interpreted as an absolute path. ^If the path does not begin 
** with a '/' (meaning that the authority section is omitted from the URI)
** then the path is interpreted as a relative path. 
** ^(On windows, the first component of an absolute path 
** is a drive specification (e.g. "C:").)^
**
** [[core URI query parameters]]
** The query component of a URI may contain parameters that are interpreted
** either by SQLite itself, or by a [VFS | custom VFS implementation].
** SQLite and its built-in [VFSes] interpret the
** following query parameters:
**
** <ul>
**   <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of
**     a VFS object that provides the operating system interface that should
**     be used to access the database file on disk. ^If this option is set to
**     an empty string the default VFS object is used. ^Specifying an unknown
**     VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is
................................................................................
**     SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to
**     sqlite3_open_v2(). ^Setting the cache parameter to "private" is 
**     equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
**     ^If sqlite3_open_v2() is used and the "cache" parameter is present in
**     a URI filename, its value overrides any behavior requested by setting
**     SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
**
**  <li> <b>psow</b>: ^The psow parameter indicates whether or not the

**     [powersafe overwrite] property does or does not apply to the
**     storage media on which the database file resides.

**
**  <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter
**     which if set disables file locking in rollback journal modes.  This
**     is useful for accessing a database on a filesystem that does not
**     support locking.  Caution:  Database corruption might result if two
**     or more processes write to the same database and any one of those
**     processes uses nolock=1.
................................................................................
** that parameter must be the byte offset
** where the NUL terminator would occur assuming the string were NUL
** terminated.  If any NUL characters occur at byte offsets less than 
** the value of the fourth parameter then the resulting string value will
** contain embedded NULs.  The result of expressions involving strings
** with embedded NULs is undefined.
**
** ^The fifth argument to the BLOB and string binding interfaces
** is a destructor used to dispose of the BLOB or
** string after SQLite has finished with it.  ^The destructor is called
** to dispose of the BLOB or string even if the call to bind API fails.

** ^If the fifth argument is
** the special value [SQLITE_STATIC], then SQLite assumes that the
** information is in static, unmanaged space and does not need to be freed.
** ^If the fifth argument has the value [SQLITE_TRANSIENT], then
** SQLite makes its own private copy of the data immediately, before
** the sqlite3_bind_*() routine returns.
**
** ^The sixth argument to sqlite3_bind_text64() must be one of
** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]
** to specify the encoding of the text in the third parameter.  If
** the sixth argument to sqlite3_bind_text64() is not one of the
** allowed values shown above, or if the text encoding is different
** from the encoding specified by the sixth parameter, then the behavior
** is undefined.
**
** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
** is filled with zeroes.  ^A zeroblob uses a fixed amount of memory
** (just an integer to hold its size) while it is being processed.
................................................................................
** of the application-defined function to be the 64-bit signed integer
** value given in the 2nd argument.
**
** ^The sqlite3_result_null() interface sets the return value
** of the application-defined function to be NULL.
**
** ^The sqlite3_result_text(), sqlite3_result_text16(),
** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
** set the return value of the application-defined function to be
** a text string which is represented as UTF-8, UTF-16 native byte order,
** UTF-16 little endian, or UTF-16 big endian, respectively.
** ^The sqlite3_result_text64() interface sets the return value of an
** application-defined function to be a text string in an encoding
** specified by the fifth (and last) parameter, which must be one
** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE].
................................................................................
#define SQLITE_TESTCTRL_ASSERT                  12
#define SQLITE_TESTCTRL_ALWAYS                  13
#define SQLITE_TESTCTRL_RESERVE                 14
#define SQLITE_TESTCTRL_OPTIMIZATIONS           15
#define SQLITE_TESTCTRL_ISKEYWORD               16
#define SQLITE_TESTCTRL_SCRATCHMALLOC           17
#define SQLITE_TESTCTRL_LOCALTIME_FAULT         18
#define SQLITE_TESTCTRL_EXPLAIN_STMT            19  /* NOT USED */
#define SQLITE_TESTCTRL_NEVER_CORRUPT           20
#define SQLITE_TESTCTRL_VDBE_COVERAGE           21
#define SQLITE_TESTCTRL_BYTEORDER               22
#define SQLITE_TESTCTRL_ISINIT                  23
#define SQLITE_TESTCTRL_SORTER_MMAP             24
#define SQLITE_TESTCTRL_LAST                    24

# define _LARGE_FILE       1
# ifndef _FILE_OFFSET_BITS
#   define _FILE_OFFSET_BITS 64
# endif
# define _LARGEFILE_SOURCE 1
#endif










/*
** For MinGW, check to see if we can include the header file containing its
** version information, among other things.  Normally, this internal MinGW
** header file would [only] be included automatically by other MinGW header
** files; however, the contained version information is now required by this
** header file to work around binary compatibility issues (see below) and
** this is the only known way to reliably obtain it.  This entire #if block
................................................................................
#pragma warn -rch /* unreachable code */
#pragma warn -ccc /* Condition is always true or false */
#pragma warn -aus /* Assigned value is never used */
#pragma warn -csu /* Comparing signed and unsigned */
#pragma warn -spa /* Suspicious pointer arithmetic */
#endif

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

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

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

/*
** A macro to hint to the compiler that a function should not be
** inlined.
*/
#if defined(__GNUC__)
#  define SQLITE_NOINLINE  __attribute__((noinline))
#elif defined(_MSC_VER)
#  define SQLITE_NOINLINE  __declspec(noinline)
#else
#  define SQLITE_NOINLINE
#endif

/*
** The SQLITE_THREADSAFE macro must be defined as 0, 1, or 2.
................................................................................

/*
** Macros to compute minimum and maximum of two numbers.
*/
#define MIN(A,B) ((A)<(B)?(A):(B))
#define MAX(A,B) ((A)>(B)?(A):(B))






/*
** Check to see if this machine uses EBCDIC.  (Yes, believe it or
** not, there are still machines out there that use EBCDIC.)
*/
#if 'A' == '\301'
# define SQLITE_EBCDIC 1
#else
................................................................................
# define SQLITE_ENABLE_STAT3_OR_STAT4 1
#elif SQLITE_ENABLE_STAT3
# define SQLITE_ENABLE_STAT3_OR_STAT4 1
#elif SQLITE_ENABLE_STAT3_OR_STAT4
# undef SQLITE_ENABLE_STAT3_OR_STAT4
#endif











/*
** An instance of the following structure is used to store the busy-handler
** callback for a given sqlite handle. 
**
** The sqlite.busyHandler member of the sqlite struct contains the busy
** callback for the database handle. Each pager opened via the sqlite
** handle is passed a pointer to sqlite.busyHandler. The busy-handler
................................................................................
typedef struct SQLiteThread SQLiteThread;
typedef struct SelectDest SelectDest;
typedef struct SrcList SrcList;
typedef struct StrAccum StrAccum;
typedef struct Table Table;
typedef struct TableLock TableLock;
typedef struct Token Token;

typedef struct Trigger Trigger;
typedef struct TriggerPrg TriggerPrg;
typedef struct TriggerStep TriggerStep;
typedef struct UnpackedRecord UnpackedRecord;
typedef struct VTable VTable;
typedef struct VtabCtx VtabCtx;
typedef struct Walker Walker;
................................................................................
/*
** Column affinity types.
**
** These used to have mnemonic name like 'i' for SQLITE_AFF_INTEGER and
** 't' for SQLITE_AFF_TEXT.  But we can save a little space and improve
** the speed a little by numbering the values consecutively.  
**
** But rather than start with 0 or 1, we begin with 'a'.  That way,
** when multiple affinity types are concatenated into a string and
** used as the P4 operand, they will be more readable.
**
** Note also that the numeric types are grouped together so that testing
** for a numeric type is a single comparison.
*/
#define SQLITE_AFF_TEXT     'a'
#define SQLITE_AFF_NONE     'b'
#define SQLITE_AFF_NUMERIC  'c'
#define SQLITE_AFF_INTEGER  'd'
#define SQLITE_AFF_REAL     'e'

#define sqlite3IsNumericAffinity(X)  ((X)>=SQLITE_AFF_NUMERIC)

/*
** The SQLITE_AFF_MASK values masks off the significant bits of an
** 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
................................................................................
  unsigned isResized:1;    /* True if resizeIndexObject() has been called */
  unsigned isCovering:1;   /* True if this is a covering index */
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
  int nSample;             /* Number of elements in aSample[] */
  int nSampleCol;          /* Size of IndexSample.anEq[] and so on */
  tRowcnt *aAvgEq;         /* Average nEq values for keys not in aSample */
  IndexSample *aSample;    /* Samples of the left-most key */

#endif
};

/*
** Allowed values for Index.idxType
*/
#define SQLITE_IDXTYPE_APPDEF      0   /* Created using CREATE INDEX */
................................................................................
#define WHERE_ORDERBY_MIN      0x0001 /* ORDER BY processing for min() func */
#define WHERE_ORDERBY_MAX      0x0002 /* ORDER BY processing for max() func */
#define WHERE_ONEPASS_DESIRED  0x0004 /* Want to do one-pass UPDATE/DELETE */
#define WHERE_DUPLICATES_OK    0x0008 /* Ok to return a row more than once */
#define WHERE_OMIT_OPEN_CLOSE  0x0010 /* Table cursors are already open */
#define WHERE_FORCE_TABLE      0x0020 /* Do not use an index-only search */
#define WHERE_ONETABLE_ONLY    0x0040 /* Only code the 1st table in pTabList */
#define WHERE_AND_ONLY         0x0080 /* Don't use indices for OR terms */
#define WHERE_GROUPBY          0x0100 /* pOrderBy is really a GROUP BY */
#define WHERE_DISTINCTBY       0x0200 /* pOrderby is really a DISTINCT clause */
#define WHERE_WANT_DISTINCT    0x0400 /* All output needs to be distinct */
#define WHERE_SORTBYGROUP      0x0800 /* Support sqlite3WhereIsSorted() */
#define WHERE_REOPEN_IDX       0x1000 /* Try to use OP_ReopenIdx */

/* Allowed return values from sqlite3WhereIsDistinct()
................................................................................
** sequences for the ORDER BY clause.
*/
struct Select {
  ExprList *pEList;      /* The fields of the result */
  u8 op;                 /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
  u16 selFlags;          /* Various SF_* values */
  int iLimit, iOffset;   /* Memory registers holding LIMIT & OFFSET counters */



  int addrOpenEphm[2];   /* OP_OpenEphem opcodes related to this select */
  u64 nSelectRow;        /* Estimated number of result rows */
  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 */
................................................................................
  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 *pParse;              /* The Parse structure */
};

/*
** Bitfield flags for P5 value in various opcodes.
*/
#define OPFLAG_NCHANGE       0x01    /* Set to update db->nChange */

#define OPFLAG_LASTROWID     0x02    /* Set to update db->lastRowid */
#define OPFLAG_ISUPDATE      0x04    /* This OP_Insert is an sql UPDATE */
#define OPFLAG_APPEND        0x08    /* This is likely to be an append */
#define OPFLAG_USESEEKRESULT 0x10    /* Try to avoid a seek in BtreeInsert() */
#define OPFLAG_CLEARCACHE    0x20    /* Clear pseudo-table cache in OP_Column */
#define OPFLAG_LENGTHARG     0x40    /* OP_Column only used for length() */
#define OPFLAG_TYPEOFARG     0x80    /* OP_Column only used for typeof() */
#define OPFLAG_BULKCSR       0x01    /* OP_Open** used to open bulk cursor */
#define OPFLAG_P2ISREG       0x02    /* P2 to OP_Open** is a register number */
#define OPFLAG_PERMUTE       0x01    /* OP_Compare: use the permutation */

/*
................................................................................
    char *zName;                    /* Name of this CTE */
    ExprList *pCols;                /* List of explicit column names, or NULL */
    Select *pSelect;                /* The definition of this CTE */
    const char *zErr;               /* Error message for circular references */
  } a[1];
};












/*
** Assuming zIn points to the first byte of a UTF-8 character,
** advance zIn to point to the first byte of the next UTF-8 character.
*/
#define SQLITE_SKIP_UTF8(zIn) {                        \
  if( (*(zIn++))>=0xc0 ){                              \
    while( (*zIn & 0xc0)==0x80 ){ zIn++; }             \
................................................................................
# define sqlite3Isspace(x)   isspace((unsigned char)(x))
# define sqlite3Isalnum(x)   isalnum((unsigned char)(x))
# define sqlite3Isalpha(x)   isalpha((unsigned char)(x))
# define sqlite3Isdigit(x)   isdigit((unsigned char)(x))
# define sqlite3Isxdigit(x)  isxdigit((unsigned char)(x))
# define sqlite3Tolower(x)   tolower((unsigned char)(x))
#endif


/*
** Internal function prototypes
*/
#define sqlite3StrICmp sqlite3_stricmp
int sqlite3Strlen30(const char*);
#define sqlite3StrNICmp sqlite3_strnicmp
................................................................................
#if defined(SQLITE_TEST) || defined(SQLITE_DEBUG)
  void sqlite3DebugPrintf(const char*, ...);
#endif
#if defined(SQLITE_TEST)
  void *sqlite3TestTextToPtr(const char*);
#endif

/* Output formatting for SQLITE_TESTCTRL_EXPLAIN */
#if defined(SQLITE_ENABLE_TREE_EXPLAIN)

  void sqlite3ExplainBegin(Vdbe*);
  void sqlite3ExplainPrintf(Vdbe*, const char*, ...);
  void sqlite3ExplainNL(Vdbe*);
  void sqlite3ExplainPush(Vdbe*);
  void sqlite3ExplainPop(Vdbe*);
  void sqlite3ExplainFinish(Vdbe*);
  void sqlite3ExplainSelect(Vdbe*, Select*);
  void sqlite3ExplainExpr(Vdbe*, Expr*);
  void sqlite3ExplainExprList(Vdbe*, ExprList*);
  const char *sqlite3VdbeExplanation(Vdbe*);
#else
# define sqlite3ExplainBegin(X)
# define sqlite3ExplainSelect(A,B)
# define sqlite3ExplainExpr(A,B)
# define sqlite3ExplainExprList(A,B)
# define sqlite3ExplainFinish(X)
# define sqlite3VdbeExplanation(X) 0
#endif


void sqlite3SetString(char **, sqlite3*, const char*, ...);
void sqlite3ErrorMsg(Parse*, const char*, ...);
int sqlite3Dequote(char*);
int sqlite3KeywordCode(const unsigned char*, int);
................................................................................
void sqlite3CommitTransaction(Parse*);
void sqlite3RollbackTransaction(Parse*);
void sqlite3Savepoint(Parse*, int, Token*);
void sqlite3CloseSavepoints(sqlite3 *);
void sqlite3LeaveMutexAndCloseZombie(sqlite3*);
int sqlite3ExprIsConstant(Expr*);
int sqlite3ExprIsConstantNotJoin(Expr*);
int sqlite3ExprIsConstantOrFunction(Expr*);
int sqlite3ExprIsInteger(Expr*, int*);
int sqlite3ExprCanBeNull(const Expr*);
int sqlite3ExprNeedsNoAffinityChange(const Expr*, char);
int sqlite3IsRowid(const char*);
void sqlite3GenerateRowDelete(Parse*,Table*,Trigger*,int,int,int,i16,u8,u8,u8);
void sqlite3GenerateRowIndexDelete(Parse*, Table*, int, int, int*);
int sqlite3GenerateIndexKey(Parse*, Index*, int, int, int, int*,Index*,int);
................................................................................
void sqlite3UniqueConstraint(Parse*, int, Index*);
void sqlite3RowidConstraint(Parse*, int, Table*);
Expr *sqlite3ExprDup(sqlite3*,Expr*,int);
ExprList *sqlite3ExprListDup(sqlite3*,ExprList*,int);
SrcList *sqlite3SrcListDup(sqlite3*,SrcList*,int);
IdList *sqlite3IdListDup(sqlite3*,IdList*);
Select *sqlite3SelectDup(sqlite3*,Select*,int);





void sqlite3FuncDefInsert(FuncDefHash*, FuncDef*);
FuncDef *sqlite3FindFunction(sqlite3*,const char*,int,int,u8,u8);
void sqlite3RegisterBuiltinFunctions(sqlite3*);
void sqlite3RegisterDateTimeFunctions(void);
void sqlite3RegisterGlobalFunctions(void);
int sqlite3SafetyCheckOk(sqlite3*);
int sqlite3SafetyCheckSickOrOk(sqlite3*);
................................................................................
  int sqlite3MemdebugNoType(void*,u8);
#else
# define sqlite3MemdebugSetType(X,Y)  /* no-op */
# define sqlite3MemdebugHasType(X,Y)  1
# define sqlite3MemdebugNoType(X,Y)   1
#endif
#define MEMTYPE_HEAP       0x01  /* General heap allocations */
#define MEMTYPE_LOOKASIDE  0x02  /* Might have been lookaside memory */
#define MEMTYPE_SCRATCH    0x04  /* Scratch allocations */
#define MEMTYPE_PCACHE     0x08  /* Page cache allocations */
#define MEMTYPE_DB         0x10  /* Uses sqlite3DbMalloc, not sqlite_malloc */


/*
** Threading interface
*/
#if SQLITE_MAX_WORKER_THREADS>0
int sqlite3ThreadCreate(SQLiteThread**,void*(*)(void*),void*);
int sqlite3ThreadJoin(SQLiteThread*, void**);
#endif

#endif /* _SQLITEINT_H_ */

# define _LARGE_FILE       1
# ifndef _FILE_OFFSET_BITS
#   define _FILE_OFFSET_BITS 64
# endif
# define _LARGEFILE_SOURCE 1
#endif

/* Needed for various definitions... */
#if defined(__GNUC__) && !defined(_GNU_SOURCE)
# define _GNU_SOURCE
#endif

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

/*
** For MinGW, check to see if we can include the header file containing its
** version information, among other things.  Normally, this internal MinGW
** header file would [only] be included automatically by other MinGW header
** files; however, the contained version information is now required by this
** header file to work around binary compatibility issues (see below) and
** this is the only known way to reliably obtain it.  This entire #if block
................................................................................
#pragma warn -rch /* unreachable code */
#pragma warn -ccc /* Condition is always true or false */
#pragma warn -aus /* Assigned value is never used */
#pragma warn -csu /* Comparing signed and unsigned */
#pragma warn -spa /* Suspicious pointer arithmetic */
#endif










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

/*
** A macro to hint to the compiler that a function should not be
** inlined.
*/
#if defined(__GNUC__)
#  define SQLITE_NOINLINE  __attribute__((noinline))
#elif defined(_MSC_VER) && _MSC_VER>=1310
#  define SQLITE_NOINLINE  __declspec(noinline)
#else
#  define SQLITE_NOINLINE
#endif

/*
** The SQLITE_THREADSAFE macro must be defined as 0, 1, or 2.
................................................................................

/*
** Macros to compute minimum and maximum of two numbers.
*/
#define MIN(A,B) ((A)<(B)?(A):(B))
#define MAX(A,B) ((A)>(B)?(A):(B))

/*
** Swap two objects of type TYPE.
*/
#define SWAP(TYPE,A,B) {TYPE t=A; A=B; B=t;}

/*
** Check to see if this machine uses EBCDIC.  (Yes, believe it or
** not, there are still machines out there that use EBCDIC.)
*/
#if 'A' == '\301'
# define SQLITE_EBCDIC 1
#else
................................................................................
# define SQLITE_ENABLE_STAT3_OR_STAT4 1
#elif SQLITE_ENABLE_STAT3
# define SQLITE_ENABLE_STAT3_OR_STAT4 1
#elif SQLITE_ENABLE_STAT3_OR_STAT4
# undef SQLITE_ENABLE_STAT3_OR_STAT4
#endif

/*
** SELECTTRACE_ENABLED will be either 1 or 0 depending on whether or not
** the Select query generator tracing logic is turned on.
*/
#if defined(SQLITE_DEBUG) || defined(SQLITE_ENABLE_SELECTTRACE)
# define SELECTTRACE_ENABLED 1
#else
# define SELECTTRACE_ENABLED 0
#endif

/*
** An instance of the following structure is used to store the busy-handler
** callback for a given sqlite handle. 
**
** The sqlite.busyHandler member of the sqlite struct contains the busy
** callback for the database handle. Each pager opened via the sqlite
** handle is passed a pointer to sqlite.busyHandler. The busy-handler
................................................................................
typedef struct SQLiteThread SQLiteThread;
typedef struct SelectDest SelectDest;
typedef struct SrcList SrcList;
typedef struct StrAccum StrAccum;
typedef struct Table Table;
typedef struct TableLock TableLock;
typedef struct Token Token;
typedef struct TreeView TreeView;
typedef struct Trigger Trigger;
typedef struct TriggerPrg TriggerPrg;
typedef struct TriggerStep TriggerStep;
typedef struct UnpackedRecord UnpackedRecord;
typedef struct VTable VTable;
typedef struct VtabCtx VtabCtx;
typedef struct Walker Walker;
................................................................................
/*
** Column affinity types.
**
** These used to have mnemonic name like 'i' for SQLITE_AFF_INTEGER and
** 't' for SQLITE_AFF_TEXT.  But we can save a little space and improve
** the speed a little by numbering the values consecutively.  
**
** But rather than start with 0 or 1, we begin with 'A'.  That way,
** when multiple affinity types are concatenated into a string and
** used as the P4 operand, they will be more readable.
**
** Note also that the numeric types are grouped together so that testing
** for a numeric type is a single comparison.  And the NONE type is first.
*/
#define SQLITE_AFF_NONE     'A'
#define SQLITE_AFF_TEXT     'B'
#define SQLITE_AFF_NUMERIC  'C'
#define SQLITE_AFF_INTEGER  'D'
#define SQLITE_AFF_REAL     'E'

#define sqlite3IsNumericAffinity(X)  ((X)>=SQLITE_AFF_NUMERIC)

/*
** The SQLITE_AFF_MASK values masks off the significant bits of an
** affinity value. 
*/
#define SQLITE_AFF_MASK     0x47

/*
** 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   0x10  /* jumps if either operand is NULL */
#define SQLITE_STOREP2      0x20  /* Store result in reg[P2] rather than jump */
#define SQLITE_NULLEQ       0x80  /* NULL=NULL */
#define SQLITE_NOTNULL      0x90  /* 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
................................................................................
  unsigned isResized:1;    /* True if resizeIndexObject() has been called */
  unsigned isCovering:1;   /* True if this is a covering index */
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
  int nSample;             /* Number of elements in aSample[] */
  int nSampleCol;          /* Size of IndexSample.anEq[] and so on */
  tRowcnt *aAvgEq;         /* Average nEq values for keys not in aSample */
  IndexSample *aSample;    /* Samples of the left-most key */
  tRowcnt *aiRowEst;       /* Non-logarithmic stat1 data for this table */
#endif
};

/*
** Allowed values for Index.idxType
*/
#define SQLITE_IDXTYPE_APPDEF      0   /* Created using CREATE INDEX */
................................................................................
#define WHERE_ORDERBY_MIN      0x0001 /* ORDER BY processing for min() func */
#define WHERE_ORDERBY_MAX      0x0002 /* ORDER BY processing for max() func */
#define WHERE_ONEPASS_DESIRED  0x0004 /* Want to do one-pass UPDATE/DELETE */
#define WHERE_DUPLICATES_OK    0x0008 /* Ok to return a row more than once */
#define WHERE_OMIT_OPEN_CLOSE  0x0010 /* Table cursors are already open */
#define WHERE_FORCE_TABLE      0x0020 /* Do not use an index-only search */
#define WHERE_ONETABLE_ONLY    0x0040 /* Only code the 1st table in pTabList */
                          /*   0x0080 // not currently used */
#define WHERE_GROUPBY          0x0100 /* pOrderBy is really a GROUP BY */
#define WHERE_DISTINCTBY       0x0200 /* pOrderby is really a DISTINCT clause */
#define WHERE_WANT_DISTINCT    0x0400 /* All output needs to be distinct */
#define WHERE_SORTBYGROUP      0x0800 /* Support sqlite3WhereIsSorted() */
#define WHERE_REOPEN_IDX       0x1000 /* Try to use OP_ReopenIdx */

/* Allowed return values from sqlite3WhereIsDistinct()
................................................................................
** sequences for the ORDER BY clause.
*/
struct Select {
  ExprList *pEList;      /* The fields of the result */
  u8 op;                 /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
  u16 selFlags;          /* Various SF_* values */
  int iLimit, iOffset;   /* Memory registers holding LIMIT & OFFSET counters */
#if SELECTTRACE_ENABLED
  char zSelName[12];     /* Symbolic name of this SELECT use for debugging */
#endif
  int addrOpenEphm[2];   /* OP_OpenEphem opcodes related to this select */
  u64 nSelectRow;        /* Estimated number of result rows */
  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 */
................................................................................
  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 */
#if SELECTTRACE_ENABLED
  int nSelect;         /* Number of SELECT statements seen */
  int nSelectIndent;   /* How far to indent SELECTTRACE() output */
#endif
#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 *pParse;              /* The Parse structure */
};

/*
** Bitfield flags for P5 value in various opcodes.
*/
#define OPFLAG_NCHANGE       0x01    /* Set to update db->nChange */
#define OPFLAG_EPHEM         0x01    /* OP_Column: Ephemeral output is ok */
#define OPFLAG_LASTROWID     0x02    /* Set to update db->lastRowid */
#define OPFLAG_ISUPDATE      0x04    /* This OP_Insert is an sql UPDATE */
#define OPFLAG_APPEND        0x08    /* This is likely to be an append */
#define OPFLAG_USESEEKRESULT 0x10    /* Try to avoid a seek in BtreeInsert() */

#define OPFLAG_LENGTHARG     0x40    /* OP_Column only used for length() */
#define OPFLAG_TYPEOFARG     0x80    /* OP_Column only used for typeof() */
#define OPFLAG_BULKCSR       0x01    /* OP_Open** used to open bulk cursor */
#define OPFLAG_P2ISREG       0x02    /* P2 to OP_Open** is a register number */
#define OPFLAG_PERMUTE       0x01    /* OP_Compare: use the permutation */

/*
................................................................................
    char *zName;                    /* Name of this CTE */
    ExprList *pCols;                /* List of explicit column names, or NULL */
    Select *pSelect;                /* The definition of this CTE */
    const char *zErr;               /* Error message for circular references */
  } a[1];
};

#ifdef SQLITE_DEBUG
/*
** An instance of the TreeView object is used for printing the content of
** data structures on sqlite3DebugPrintf() using a tree-like view.
*/
struct TreeView {
  int iLevel;             /* Which level of the tree we are on */
  u8  bLine[100];         /* Draw vertical in column i if bLine[i] is true */
};
#endif /* SQLITE_DEBUG */

/*
** Assuming zIn points to the first byte of a UTF-8 character,
** advance zIn to point to the first byte of the next UTF-8 character.
*/
#define SQLITE_SKIP_UTF8(zIn) {                        \
  if( (*(zIn++))>=0xc0 ){                              \
    while( (*zIn & 0xc0)==0x80 ){ zIn++; }             \
................................................................................
# define sqlite3Isspace(x)   isspace((unsigned char)(x))
# define sqlite3Isalnum(x)   isalnum((unsigned char)(x))
# define sqlite3Isalpha(x)   isalpha((unsigned char)(x))
# define sqlite3Isdigit(x)   isdigit((unsigned char)(x))
# define sqlite3Isxdigit(x)  isxdigit((unsigned char)(x))
# define sqlite3Tolower(x)   tolower((unsigned char)(x))
#endif
int sqlite3IsIdChar(u8);

/*
** Internal function prototypes
*/
#define sqlite3StrICmp sqlite3_stricmp
int sqlite3Strlen30(const char*);
#define sqlite3StrNICmp sqlite3_strnicmp
................................................................................
#if defined(SQLITE_TEST) || defined(SQLITE_DEBUG)
  void sqlite3DebugPrintf(const char*, ...);
#endif
#if defined(SQLITE_TEST)
  void *sqlite3TestTextToPtr(const char*);
#endif


#if defined(SQLITE_DEBUG)
  TreeView *sqlite3TreeViewPush(TreeView*,u8);
  void sqlite3TreeViewPop(TreeView*);
  void sqlite3TreeViewLine(TreeView*, const char*, ...);
  void sqlite3TreeViewItem(TreeView*, const char*, u8);
  void sqlite3TreeViewExpr(TreeView*, const Expr*, u8);
  void sqlite3TreeViewExprList(TreeView*, const ExprList*, u8, const char*);
  void sqlite3TreeViewSelect(TreeView*, const Select*, u8);











#endif


void sqlite3SetString(char **, sqlite3*, const char*, ...);
void sqlite3ErrorMsg(Parse*, const char*, ...);
int sqlite3Dequote(char*);
int sqlite3KeywordCode(const unsigned char*, int);
................................................................................
void sqlite3CommitTransaction(Parse*);
void sqlite3RollbackTransaction(Parse*);
void sqlite3Savepoint(Parse*, int, Token*);
void sqlite3CloseSavepoints(sqlite3 *);
void sqlite3LeaveMutexAndCloseZombie(sqlite3*);
int sqlite3ExprIsConstant(Expr*);
int sqlite3ExprIsConstantNotJoin(Expr*);
int sqlite3ExprIsConstantOrFunction(Expr*, u8);
int sqlite3ExprIsInteger(Expr*, int*);
int sqlite3ExprCanBeNull(const Expr*);
int sqlite3ExprNeedsNoAffinityChange(const Expr*, char);
int sqlite3IsRowid(const char*);
void sqlite3GenerateRowDelete(Parse*,Table*,Trigger*,int,int,int,i16,u8,u8,u8);
void sqlite3GenerateRowIndexDelete(Parse*, Table*, int, int, int*);
int sqlite3GenerateIndexKey(Parse*, Index*, int, int, int, int*,Index*,int);
................................................................................
void sqlite3UniqueConstraint(Parse*, int, Index*);
void sqlite3RowidConstraint(Parse*, int, Table*);
Expr *sqlite3ExprDup(sqlite3*,Expr*,int);
ExprList *sqlite3ExprListDup(sqlite3*,ExprList*,int);
SrcList *sqlite3SrcListDup(sqlite3*,SrcList*,int);
IdList *sqlite3IdListDup(sqlite3*,IdList*);
Select *sqlite3SelectDup(sqlite3*,Select*,int);
#if SELECTTRACE_ENABLED
void sqlite3SelectSetName(Select*,const char*);
#else
# define sqlite3SelectSetName(A,B)
#endif
void sqlite3FuncDefInsert(FuncDefHash*, FuncDef*);
FuncDef *sqlite3FindFunction(sqlite3*,const char*,int,int,u8,u8);
void sqlite3RegisterBuiltinFunctions(sqlite3*);
void sqlite3RegisterDateTimeFunctions(void);
void sqlite3RegisterGlobalFunctions(void);
int sqlite3SafetyCheckOk(sqlite3*);
int sqlite3SafetyCheckSickOrOk(sqlite3*);
................................................................................
  int sqlite3MemdebugNoType(void*,u8);
#else
# define sqlite3MemdebugSetType(X,Y)  /* no-op */
# define sqlite3MemdebugHasType(X,Y)  1
# define sqlite3MemdebugNoType(X,Y)   1
#endif
#define MEMTYPE_HEAP       0x01  /* General heap allocations */
#define MEMTYPE_LOOKASIDE  0x02  /* Heap that might have been lookaside */
#define MEMTYPE_SCRATCH    0x04  /* Scratch allocations */
#define MEMTYPE_PCACHE     0x08  /* Page cache allocations */



/*
** Threading interface
*/
#if SQLITE_MAX_WORKER_THREADS>0
int sqlite3ThreadCreate(SQLiteThread**,void*(*)(void*),void*);
int sqlite3ThreadJoin(SQLiteThread*, void**);
#endif

#endif /* _SQLITEINT_H_ */

      db->pnBytesFreed = &nByte;
      for(pVdbe=db->pVdbe; pVdbe; pVdbe=pVdbe->pNext){
        sqlite3VdbeClearObject(db, pVdbe);
        sqlite3DbFree(db, pVdbe);
      }
      db->pnBytesFreed = 0;

      *pHighwater = 0;
      *pCurrent = nByte;

      break;
    }

    /*
    ** Set *pCurrent to the total cache hits or misses encountered by all
................................................................................

      for(i=0; i<db->nDb; i++){
        if( db->aDb[i].pBt ){
          Pager *pPager = sqlite3BtreePager(db->aDb[i].pBt);
          sqlite3PagerCacheStat(pPager, op, resetFlag, &nRet);
        }
      }
      *pHighwater = 0;


      *pCurrent = nRet;
      break;
    }

    /* Set *pCurrent to non-zero if there are unresolved deferred foreign
    ** key constraints.  Set *pCurrent to zero if all foreign key constraints
    ** have been satisfied.  The *pHighwater is always set to zero.
    */
    case SQLITE_DBSTATUS_DEFERRED_FKS: {
      *pHighwater = 0;
      *pCurrent = db->nDeferredImmCons>0 || db->nDeferredCons>0;
      break;
    }

    default: {
      rc = SQLITE_ERROR;
    }
  }
  sqlite3_mutex_leave(db->mutex);
  return rc;
}

      db->pnBytesFreed = &nByte;
      for(pVdbe=db->pVdbe; pVdbe; pVdbe=pVdbe->pNext){
        sqlite3VdbeClearObject(db, pVdbe);
        sqlite3DbFree(db, pVdbe);
      }
      db->pnBytesFreed = 0;

      *pHighwater = 0;  /* IMP: R-64479-57858 */
      *pCurrent = nByte;

      break;
    }

    /*
    ** Set *pCurrent to the total cache hits or misses encountered by all
................................................................................

      for(i=0; i<db->nDb; i++){
        if( db->aDb[i].pBt ){
          Pager *pPager = sqlite3BtreePager(db->aDb[i].pBt);
          sqlite3PagerCacheStat(pPager, op, resetFlag, &nRet);
        }
      }
      *pHighwater = 0; /* IMP: R-42420-56072 */
                       /* IMP: R-54100-20147 */
                       /* IMP: R-29431-39229 */
      *pCurrent = nRet;
      break;
    }

    /* Set *pCurrent to non-zero if there are unresolved deferred foreign
    ** key constraints.  Set *pCurrent to zero if all foreign key constraints
    ** have been satisfied.  The *pHighwater is always set to zero.
    */
    case SQLITE_DBSTATUS_DEFERRED_FKS: {
      *pHighwater = 0;  /* IMP: R-11967-56545 */
      *pCurrent = db->nDeferredImmCons>0 || db->nDeferredCons>0;
      break;
    }

    default: {
      rc = SQLITE_ERROR;
    }
  }
  sqlite3_mutex_leave(db->mutex);
  return rc;
}

    { "SQLITE_LIMIT_COMPOUND_SELECT",     SQLITE_LIMIT_COMPOUND_SELECT      },
    { "SQLITE_LIMIT_VDBE_OP",             SQLITE_LIMIT_VDBE_OP              },
    { "SQLITE_LIMIT_FUNCTION_ARG",        SQLITE_LIMIT_FUNCTION_ARG         },
    { "SQLITE_LIMIT_ATTACHED",            SQLITE_LIMIT_ATTACHED             },
    { "SQLITE_LIMIT_LIKE_PATTERN_LENGTH", SQLITE_LIMIT_LIKE_PATTERN_LENGTH  },
    { "SQLITE_LIMIT_VARIABLE_NUMBER",     SQLITE_LIMIT_VARIABLE_NUMBER      },
    { "SQLITE_LIMIT_TRIGGER_DEPTH",       SQLITE_LIMIT_TRIGGER_DEPTH        },

    
    /* Out of range test cases */
    { "SQLITE_LIMIT_TOOSMALL",            -1,                               },
    { "SQLITE_LIMIT_TOOBIG",              SQLITE_LIMIT_TRIGGER_DEPTH+1      },
  };
  int i, id;
  int val;
  const char *zId;

  if( objc!=4 ){
    Tcl_AppendResult(interp, "wrong # args: should be \"",

    { "SQLITE_LIMIT_COMPOUND_SELECT",     SQLITE_LIMIT_COMPOUND_SELECT      },
    { "SQLITE_LIMIT_VDBE_OP",             SQLITE_LIMIT_VDBE_OP              },
    { "SQLITE_LIMIT_FUNCTION_ARG",        SQLITE_LIMIT_FUNCTION_ARG         },
    { "SQLITE_LIMIT_ATTACHED",            SQLITE_LIMIT_ATTACHED             },
    { "SQLITE_LIMIT_LIKE_PATTERN_LENGTH", SQLITE_LIMIT_LIKE_PATTERN_LENGTH  },
    { "SQLITE_LIMIT_VARIABLE_NUMBER",     SQLITE_LIMIT_VARIABLE_NUMBER      },
    { "SQLITE_LIMIT_TRIGGER_DEPTH",       SQLITE_LIMIT_TRIGGER_DEPTH        },
    { "SQLITE_LIMIT_WORKER_THREADS",      SQLITE_LIMIT_WORKER_THREADS       },
    
    /* Out of range test cases */
    { "SQLITE_LIMIT_TOOSMALL",            -1,                               },
    { "SQLITE_LIMIT_TOOBIG",              SQLITE_LIMIT_WORKER_THREADS+1     },
  };
  int i, id;
  int val;
  const char *zId;

  if( objc!=4 ){
    Tcl_AppendResult(interp, "wrong # args: should be \"",

  LINKVAR( MAX_TRIGGER_DEPTH );
  LINKVAR( DEFAULT_TEMP_CACHE_SIZE );
  LINKVAR( DEFAULT_CACHE_SIZE );
  LINKVAR( DEFAULT_PAGE_SIZE );
  LINKVAR( DEFAULT_FILE_FORMAT );
  LINKVAR( MAX_ATTACHED );
  LINKVAR( MAX_DEFAULT_PAGE_SIZE );


  {
    static const int cv_TEMP_STORE = SQLITE_TEMP_STORE;
    Tcl_LinkVar(interp, "TEMP_STORE", (char *)&(cv_TEMP_STORE),
                TCL_LINK_INT | TCL_LINK_READ_ONLY);
  }

  LINKVAR( MAX_TRIGGER_DEPTH );
  LINKVAR( DEFAULT_TEMP_CACHE_SIZE );
  LINKVAR( DEFAULT_CACHE_SIZE );
  LINKVAR( DEFAULT_PAGE_SIZE );
  LINKVAR( DEFAULT_FILE_FORMAT );
  LINKVAR( MAX_ATTACHED );
  LINKVAR( MAX_DEFAULT_PAGE_SIZE );
  LINKVAR( MAX_WORKER_THREADS );

  {
    static const int cv_TEMP_STORE = SQLITE_TEMP_STORE;
    Tcl_LinkVar(interp, "TEMP_STORE", (char *)&(cv_TEMP_STORE),
                TCL_LINK_INT | TCL_LINK_READ_ONLY);
  }

    pHdr += sqlite3GetVarint(pHdr, &iSerialType);
    pBody += sqlite3VdbeSerialGet(pBody, (u32)iSerialType, &mem);

    if( iCurrent==iIdx ){
      sqlite3_result_value(context, &mem);
    }

    sqlite3DbFree(db, mem.zMalloc);
  }
}

/*
** tclcmd: test_decode(record)
**
** This function implements an SQL user-function that accepts a blob
................................................................................

      default:
        assert( 0 );
    }

    Tcl_ListObjAppendElement(0, pRet, pVal);

    if( mem.zMalloc ){
      sqlite3DbFree(db, mem.zMalloc);
    }
  }

  sqlite3_result_text(context, Tcl_GetString(pRet), -1, SQLITE_TRANSIENT);
  Tcl_DecrRefCount(pRet);
}

    pHdr += sqlite3GetVarint(pHdr, &iSerialType);
    pBody += sqlite3VdbeSerialGet(pBody, (u32)iSerialType, &mem);

    if( iCurrent==iIdx ){
      sqlite3_result_value(context, &mem);
    }

    if( mem.szMalloc ) sqlite3DbFree(db, mem.zMalloc);
  }
}

/*
** tclcmd: test_decode(record)
**
** This function implements an SQL user-function that accepts a blob
................................................................................

      default:
        assert( 0 );
    }

    Tcl_ListObjAppendElement(0, pRet, pVal);

    if( mem.szMalloc ){
      sqlite3DbFree(db, mem.zMalloc);
    }
  }

  sqlite3_result_text(context, Tcl_GetString(pRet), -1, SQLITE_TRANSIENT);
  Tcl_DecrRefCount(pRet);
}

      rc = SQLITE_OK;
      break;
    case SQLITE_FCNTL_SIZE_HINT:
    case SQLITE_FCNTL_CHUNK_SIZE:
      /* no-op these */
      rc = SQLITE_OK;
      break;




















    default:
      pSubOpen = multiplexSubOpen(pGroup, 0, &rc, NULL, 0);
      if( pSubOpen ){
        rc = pSubOpen->pMethods->xFileControl(pSubOpen, op, pArg);
        if( op==SQLITE_FCNTL_VFSNAME && rc==SQLITE_OK ){
         *(char**)pArg = sqlite3_mprintf("multiplex/%z", *(char**)pArg);
        }

      rc = SQLITE_OK;
      break;
    case SQLITE_FCNTL_SIZE_HINT:
    case SQLITE_FCNTL_CHUNK_SIZE:
      /* no-op these */
      rc = SQLITE_OK;
      break;
    case SQLITE_FCNTL_PRAGMA: {
      char **aFcntl = (char**)pArg;
      if( aFcntl[1] && sqlite3_stricmp(aFcntl[1],"multiplex_truncate")==0 ){
        if( aFcntl[2] && aFcntl[2][0] ){
          if( sqlite3_stricmp(aFcntl[2], "on")==0
           || sqlite3_stricmp(aFcntl[2], "1")==0 ){
            pGroup->bTruncate = 1;
          }else
          if( sqlite3_stricmp(aFcntl[2], "off")==0
           || sqlite3_stricmp(aFcntl[2], "0")==0 ){
            pGroup->bTruncate = 0;
          }
        }
        aFcntl[0] = sqlite3_mprintf(pGroup->bTruncate ? "on" : "off");
        rc = SQLITE_OK;
        break;
      }
      /* If the multiplexor does not handle the pragma, pass it through
      ** into the default case. */
    }
    default:
      pSubOpen = multiplexSubOpen(pGroup, 0, &rc, NULL, 0);
      if( pSubOpen ){
        rc = pSubOpen->pMethods->xFileControl(pSubOpen, op, pArg);
        if( op==SQLITE_FCNTL_VFSNAME && rc==SQLITE_OK ){
         *(char**)pArg = sqlite3_mprintf("multiplex/%z", *(char**)pArg);
        }

}

#endif /* SQLITE_OS_UNIX && defined(SQLITE_MUTEX_PTHREADS) */
/******************************** End Unix Pthreads *************************/


/********************************* Win32 Threads ****************************/
#if SQLITE_OS_WIN && !SQLITE_OS_WINRT && SQLITE_THREADSAFE>0

#define SQLITE_THREADS_IMPLEMENTED 1  /* Prevent the single-thread code below */
#include <process.h>

/* A running thread */
struct SQLiteThread {
  uintptr_t tid;           /* The thread handle */
  unsigned id;             /* The thread identifier */
  void *(*xTask)(void*);   /* The routine to run as a thread */
  void *pIn;               /* Argument to xTask */
  void *pResult;           /* Result of xTask */
};

/* Thread procedure Win32 compatibility shim */
................................................................................
  p = sqlite3Malloc(sizeof(*p));
  if( p==0 ) return SQLITE_NOMEM;
  if( sqlite3GlobalConfig.bCoreMutex==0 ){
    memset(p, 0, sizeof(*p));
  }else{
    p->xTask = xTask;
    p->pIn = pIn;
    p->tid = _beginthreadex(0, 0, sqlite3ThreadProc, p, 0, &p->id);
    if( p->tid==0 ){
      memset(p, 0, sizeof(*p));
    }
  }
  if( p->xTask==0 ){
    p->id = GetCurrentThreadId();
    p->pResult = xTask(pIn);
................................................................................
    assert( bRc );
  }
  if( rc==WAIT_OBJECT_0 ) *ppOut = p->pResult;
  sqlite3_free(p);
  return (rc==WAIT_OBJECT_0) ? SQLITE_OK : SQLITE_ERROR;
}

#endif /* SQLITE_OS_WIN && !SQLITE_OS_WINRT */
/******************************** End Win32 Threads *************************/


/********************************* Single-Threaded **************************/
#ifndef SQLITE_THREADS_IMPLEMENTED
/*
** This implementation does not actually create a new thread.  It does the

}

#endif /* SQLITE_OS_UNIX && defined(SQLITE_MUTEX_PTHREADS) */
/******************************** End Unix Pthreads *************************/


/********************************* Win32 Threads ****************************/
#if SQLITE_OS_WIN && !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && SQLITE_THREADSAFE>0

#define SQLITE_THREADS_IMPLEMENTED 1  /* Prevent the single-thread code below */
#include <process.h>

/* A running thread */
struct SQLiteThread {
  void *tid;               /* The thread handle */
  unsigned id;             /* The thread identifier */
  void *(*xTask)(void*);   /* The routine to run as a thread */
  void *pIn;               /* Argument to xTask */
  void *pResult;           /* Result of xTask */
};

/* Thread procedure Win32 compatibility shim */
................................................................................
  p = sqlite3Malloc(sizeof(*p));
  if( p==0 ) return SQLITE_NOMEM;
  if( sqlite3GlobalConfig.bCoreMutex==0 ){
    memset(p, 0, sizeof(*p));
  }else{
    p->xTask = xTask;
    p->pIn = pIn;
    p->tid = (void*)_beginthreadex(0, 0, sqlite3ThreadProc, p, 0, &p->id);
    if( p->tid==0 ){
      memset(p, 0, sizeof(*p));
    }
  }
  if( p->xTask==0 ){
    p->id = GetCurrentThreadId();
    p->pResult = xTask(pIn);
................................................................................
    assert( bRc );
  }
  if( rc==WAIT_OBJECT_0 ) *ppOut = p->pResult;
  sqlite3_free(p);
  return (rc==WAIT_OBJECT_0) ? SQLITE_OK : SQLITE_ERROR;
}

#endif /* SQLITE_OS_WIN && !SQLITE_OS_WINCE && !SQLITE_OS_WINRT */
/******************************** End Win32 Threads *************************/


/********************************* Single-Threaded **************************/
#ifndef SQLITE_THREADS_IMPLEMENTED
/*
** This implementation does not actually create a new thread.  It does the

    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1,  /* Cx */
    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1,  /* Dx */
    0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1,  /* Ex */
    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0,  /* Fx */
};
#define IdChar(C)  (((c=C)>=0x42 && sqlite3IsEbcdicIdChar[c-0x40]))
#endif



/*
** Return the length of the token that begins at z[0]. 
** Store the token type in *tokenType before returning.
*/
int sqlite3GetToken(const unsigned char *z, int *tokenType){

    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1,  /* Cx */
    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1,  /* Dx */
    0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1,  /* Ex */
    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0,  /* Fx */
};
#define IdChar(C)  (((c=C)>=0x42 && sqlite3IsEbcdicIdChar[c-0x40]))
#endif
int sqlite3IsIdChar(u8 c){ return IdChar(c); }


/*
** Return the length of the token that begins at z[0]. 
** Store the token type in *tokenType before returning.
*/
int sqlite3GetToken(const unsigned char *z, int *tokenType){

  c = pMem->flags;
  sqlite3VdbeMemRelease(pMem);
  pMem->flags = MEM_Str|MEM_Term|(c&MEM_AffMask);
  pMem->enc = desiredEnc;
  pMem->z = (char*)zOut;
  pMem->zMalloc = pMem->z;


translate_out:
#if defined(TRANSLATE_TRACE) && defined(SQLITE_DEBUG)
  {
    char zBuf[100];
    sqlite3VdbeMemPrettyPrint(pMem, zBuf);
    fprintf(stderr, "OUTPUT: %s\n", zBuf);

  c = pMem->flags;
  sqlite3VdbeMemRelease(pMem);
  pMem->flags = MEM_Str|MEM_Term|(c&MEM_AffMask);
  pMem->enc = desiredEnc;
  pMem->z = (char*)zOut;
  pMem->zMalloc = pMem->z;
  pMem->szMalloc = sqlite3DbMallocSize(pMem->db, pMem->z);

translate_out:
#if defined(TRANSLATE_TRACE) && defined(SQLITE_DEBUG)
  {
    char zBuf[100];
    sqlite3VdbeMemPrettyPrint(pMem, zBuf);
    fprintf(stderr, "OUTPUT: %s\n", zBuf);

      (isBtreeCursor?sqlite3BtreeCursorSize():0);

  assert( iCur<p->nCursor );
  if( p->apCsr[iCur] ){
    sqlite3VdbeFreeCursor(p, p->apCsr[iCur]);
    p->apCsr[iCur] = 0;
  }
  if( SQLITE_OK==sqlite3VdbeMemGrow(pMem, nByte, 0) ){
    p->apCsr[iCur] = pCx = (VdbeCursor*)pMem->z;
    memset(pCx, 0, sizeof(VdbeCursor));
    pCx->iDb = iDb;
    pCx->nField = nField;

    if( isBtreeCursor ){
      pCx->pCursor = (BtCursor*)
          &pMem->z[ROUND8(sizeof(VdbeCursor))+2*sizeof(u32)*nField];
      sqlite3BtreeCursorZero(pCx->pCursor);
    }
  }
  return pCx;
................................................................................
** point or exponential notation, the result is only MEM_Real, even
** if there is an exact integer representation of the quantity.
*/
static void applyNumericAffinity(Mem *pRec, int bTryForInt){
  double rValue;
  i64 iValue;
  u8 enc = pRec->enc;
  if( (pRec->flags&MEM_Str)==0 ) return;
  if( sqlite3AtoF(pRec->z, &rValue, pRec->n, enc)==0 ) return;
  if( 0==sqlite3Atoi64(pRec->z, &iValue, pRec->n, enc) ){
    pRec->u.i = iValue;
    pRec->flags |= MEM_Int;
  }else{
    pRec->r = rValue;
    pRec->flags |= MEM_Real;
    if( bTryForInt ) sqlite3VdbeIntegerAffinity(pRec);
  }
}

/*
** Processing is determine by the affinity parameter:
................................................................................
**    No-op.  pRec is unchanged.
*/
static void applyAffinity(
  Mem *pRec,          /* The value to apply affinity to */
  char affinity,      /* The affinity to be applied */
  u8 enc              /* Use this text encoding */
){










  if( affinity==SQLITE_AFF_TEXT ){
    /* Only attempt the conversion to TEXT if there is an integer or real
    ** representation (blob and NULL do not get converted) but no string
    ** representation.
    */
    if( 0==(pRec->flags&MEM_Str) && (pRec->flags&(MEM_Real|MEM_Int)) ){
      sqlite3VdbeMemStringify(pRec, enc, 1);
    }
  }else if( affinity!=SQLITE_AFF_NONE ){
    assert( affinity==SQLITE_AFF_INTEGER || affinity==SQLITE_AFF_REAL
             || affinity==SQLITE_AFF_NUMERIC );
    if( (pRec->flags & MEM_Int)==0 ){
      if( (pRec->flags & MEM_Real)==0 ){
        applyNumericAffinity(pRec,1);
      }else{
        sqlite3VdbeIntegerAffinity(pRec);
      }
    }
  }
}

/*
** 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
................................................................................
){
  applyAffinity((Mem *)pVal, affinity, enc);
}

/*
** pMem currently only holds a string type (or maybe a BLOB that we can
** interpret as a string if we want to).  Compute its corresponding
** numeric type, if has one.  Set the pMem->r and pMem->u.i fields
** accordingly.
*/
static u16 SQLITE_NOINLINE computeNumericType(Mem *pMem){
  assert( (pMem->flags & (MEM_Int|MEM_Real))==0 );
  assert( (pMem->flags & (MEM_Str|MEM_Blob))!=0 );
  if( sqlite3AtoF(pMem->z, &pMem->r, pMem->n, pMem->enc)==0 ){
    return 0;
  }
  if( sqlite3Atoi64(pMem->z, &pMem->u.i, pMem->n, pMem->enc)==SQLITE_OK ){
    return MEM_Int;
  }
  return MEM_Real;
}

/*
** Return the numeric type for pMem, either MEM_Int or MEM_Real or both or
** none.  
**
** Unlike applyNumericAffinity(), this routine does not modify pMem->flags.
** But it does set pMem->r and pMem->u.i appropriately.
*/
static u16 numericType(Mem *pMem){
  if( pMem->flags & (MEM_Int|MEM_Real) ){
    return pMem->flags & (MEM_Int|MEM_Real);
  }
  if( pMem->flags & (MEM_Str|MEM_Blob) ){
    return computeNumericType(pMem);
................................................................................
    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);
#ifndef SQLITE_OMIT_FLOATING_POINT
  }else if( p->flags & MEM_Real ){
    printf(" r:%g", p->r);
#endif
  }else if( p->flags & MEM_RowSet ){
    printf(" (rowset)");
  }else{
    char zBuf[200];
    sqlite3VdbeMemPrettyPrint(p, zBuf);
    printf(" %s", zBuf);
................................................................................
**
** P4 is a pointer to a 64-bit floating point value.
** Write that value into register P2.
*/
case OP_Real: {            /* same as TK_FLOAT, out2-prerelease */
  pOut->flags = MEM_Real;
  assert( !sqlite3IsNaN(*pOp->p4.pReal) );
  pOut->r = *pOp->p4.pReal;
  break;
}
#endif

/* Opcode: String8 * P2 * P4 *
** Synopsis: r[P2]='P4'
**
................................................................................
  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;
................................................................................
** Move the P3 values in register P1..P1+P3-1 over into
** registers P2..P2+P3-1.  Registers P1..P1+P3-1 are
** left holding a NULL.  It is an error for register ranges
** P1..P1+P3-1 and P2..P2+P3-1 to overlap.  It is an error
** for P3 to be less than 1.
*/
case OP_Move: {
  char *zMalloc;   /* Holding variable for allocated memory */
  int n;           /* Number of registers left to copy */
  int p1;          /* Register to copy from */
  int p2;          /* Register to copy to */

  n = pOp->p3;
  p1 = pOp->p1;
  p2 = pOp->p2;
................................................................................
  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);
    sqlite3VdbeMemRelease(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->zMalloc = zMalloc;
    REGISTER_TRACE(p2++, pOut);
    pIn1++;
    pOut++;
  }while( --n );
  break;
}

................................................................................
#ifdef SQLITE_OMIT_FLOATING_POINT
    pOut->u.i = rB;
    MemSetTypeFlag(pOut, MEM_Int);
#else
    if( sqlite3IsNaN(rB) ){
      goto arithmetic_result_is_null;
    }
    pOut->r = rB;
    MemSetTypeFlag(pOut, MEM_Real);
    if( ((type1|type2)&MEM_Real)==0 && !bIntint ){
      sqlite3VdbeIntegerAffinity(pOut);
    }
#endif
  }
  break;
................................................................................
  }

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

  ctx.fErrorOrAux = 0;
  if( ctx.pFunc->funcFlags & SQLITE_FUNC_NEEDCOLL ){
    assert( pOp>aOp );
    assert( pOp[-1].p4type==P4_COLLSEQ );
    assert( pOp[-1].opcode==OP_CollSeq );
    ctx.pColl = pOp[-1].p4.pColl;
  }
  db->lastRowid = lastRowid;
  (*ctx.pFunc->xFunc)(&ctx, n, apVal); /* IMP: R-24505-23230 */
  lastRowid = db->lastRowid;

  /* If the function returned an error, throw an exception */
  if( ctx.fErrorOrAux ){
    if( ctx.isError ){
      sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3_value_text(ctx.pOut));
      rc = ctx.isError;
    }
................................................................................
** <li value="100"> INTEGER
** <li value="101"> REAL
** </ul>
**
** A NULL value is not changed by this routine.  It remains NULL.
*/
case OP_Cast: {                  /* in1 */
  assert( pOp->p2>=SQLITE_AFF_TEXT && pOp->p2<=SQLITE_AFF_REAL );
  testcase( pOp->p2==SQLITE_AFF_TEXT );
  testcase( pOp->p2==SQLITE_AFF_NONE );
  testcase( pOp->p2==SQLITE_AFF_NUMERIC );
  testcase( pOp->p2==SQLITE_AFF_INTEGER );
  testcase( pOp->p2==SQLITE_AFF_REAL );
  pIn1 = &aMem[pOp->p1];
  memAboutToChange(p, pIn1);
................................................................................
        }
      }
      break;
    }
  }else{
    /* Neither operand is NULL.  Do a comparison. */
    affinity = pOp->p5 & SQLITE_AFF_MASK;
    if( affinity ){

      applyAffinity(pIn1, affinity, encoding);


      applyAffinity(pIn3, affinity, encoding);
      if( db->mallocFailed ) goto no_mem;
    }












    assert( pOp->p4type==P4_COLLSEQ || pOp->p4.pColl==0 );
    if( pIn1->flags & MEM_Zero ){
      sqlite3VdbeMemExpandBlob(pIn1);
      flags1 &= ~MEM_Zero;
    }
    if( pIn3->flags & MEM_Zero ){
      sqlite3VdbeMemExpandBlob(pIn3);
      flags3 &= ~MEM_Zero;
    }

    res = sqlite3MemCompare(pIn3, pIn1, pOp->p4.pColl);
  }
  switch( pOp->opcode ){
    case OP_Eq:    res = res==0;     break;
    case OP_Ne:    res = res!=0;     break;
    case OP_Lt:    res = res<0;      break;
    case OP_Le:    res = res<=0;     break;
................................................................................
** skipped for length() and all content loading can be skipped for typeof().
*/
case OP_Column: {
  i64 payloadSize64; /* Number of bytes in the record */
  int p2;            /* column number to retrieve */
  VdbeCursor *pC;    /* The VDBE cursor */
  BtCursor *pCrsr;   /* The BTree cursor */
  u32 *aType;        /* aType[i] holds the numeric type of the i-th column */
  u32 *aOffset;      /* aOffset[i] is offset to start of data for i-th column */
  int len;           /* The length of the serialized data for the column */
  int i;             /* Loop counter */
  Mem *pDest;        /* Where to write the extracted value */
  Mem sMem;          /* For storing the record being decoded */
  const u8 *zData;   /* Part of the record being decoded */
  const u8 *zHdr;    /* Next unparsed byte of the header */
  const u8 *zEndHdr; /* Pointer to first byte after the header */
  u32 offset;        /* Offset into the data */
  u32 szField;       /* Number of bytes in the content of a field */
  u32 avail;         /* Number of bytes of available data */
  u32 t;             /* A type code from the record header */

  Mem *pReg;         /* PseudoTable input register */

  p2 = pOp->p2;
  assert( pOp->p3>0 && pOp->p3<=(p->nMem-p->nCursor) );
  pDest = &aMem[pOp->p3];
  memAboutToChange(p, pDest);
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );
  assert( p2<pC->nField );
  aType = pC->aType;
  aOffset = aType + pC->nField;
#ifndef SQLITE_OMIT_VIRTUALTABLE
  assert( pC->pVtabCursor==0 ); /* OP_Column never called on virtual table */
#endif
  pCrsr = pC->pCursor;
  assert( pCrsr!=0 || pC->pseudoTableReg>0 ); /* pCrsr NULL on PseudoTables */
  assert( pCrsr!=0 || pC->nullRow );          /* pC->nullRow on PseudoTables */

  /* If the cursor cache is stale, bring it up-to-date */
  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;
................................................................................
        goto too_big;
      }
    }
    pC->cacheStatus = p->cacheCtr;
    pC->iHdrOffset = getVarint32(pC->aRow, offset);
    pC->nHdrParsed = 0;
    aOffset[0] = offset;
    if( avail<offset ){
      /* pC->aRow does not have to hold the entire row, but it does at least
      ** need to cover the header of the record.  If pC->aRow does not contain
      ** the complete header, then set it to zero, forcing the header to be
      ** dynamically allocated. */
      pC->aRow = 0;
      pC->szRow = 0;
    }

    /* Make sure a corrupt database has not given us an oversize header.
    ** Do this now to avoid an oversize memory allocation.
    **
    ** Type entries can be between 1 and 5 bytes each.  But 4 and 5 byte
    ** types use so much data space that there can only be 4096 and 32 of
    ** them, respectively.  So the maximum header length results from a
................................................................................
    ** 3-byte type for each of the maximum of 32768 columns plus three
    ** extra bytes for the header length itself.  32768*3 + 3 = 98307.
    */
    if( offset > 98307 || offset > pC->payloadSize ){
      rc = SQLITE_CORRUPT_BKPT;
      goto op_column_error;
    }
















  }

  /* Make sure at least the first p2+1 entries of the header have been
  ** parsed and valid information is in aOffset[] and aType[].
  */
  if( pC->nHdrParsed<=p2 ){
    /* If there is more header available for parsing in the record, try
    ** to extract additional fields up through the p2+1-th field 
    */

    if( pC->iHdrOffset<aOffset[0] ){
      /* Make sure zData points to enough of the record to cover the header. */
      if( pC->aRow==0 ){
        memset(&sMem, 0, sizeof(sMem));
        rc = sqlite3VdbeMemFromBtree(pCrsr, 0, aOffset[0], 
                                     !pC->isTable, &sMem);
        if( rc!=SQLITE_OK ){
................................................................................
          goto op_column_error;
        }
        zData = (u8*)sMem.z;
      }else{
        zData = pC->aRow;
      }
  
      /* Fill in aType[i] and aOffset[i] values through the p2-th field. */
      i = pC->nHdrParsed;
      offset = aOffset[i];
      zHdr = zData + pC->iHdrOffset;
      zEndHdr = zData + aOffset[0];
      assert( i<=p2 && zHdr<zEndHdr );
      do{
        if( zHdr[0]<0x80 ){
          t = zHdr[0];
          zHdr++;
        }else{
          zHdr += sqlite3GetVarint32(zHdr, &t);
        }
        aType[i] = t;
        szField = sqlite3VdbeSerialTypeLen(t);
        offset += szField;
        if( offset<szField ){  /* True if offset overflows */
          zHdr = &zEndHdr[1];  /* Forces SQLITE_CORRUPT return below */
          break;
        }
        i++;
................................................................................
      pC->nHdrParsed = i;
      pC->iHdrOffset = (u32)(zHdr - zData);
      if( pC->aRow==0 ){
        sqlite3VdbeMemRelease(&sMem);
        sMem.flags = MEM_Null;
      }
  
      /* If we have read more header data than was contained in the header,
      ** or if the end of the last field appears to be past the end of the
      ** record, or if the end of the last field appears to be before the end
      ** of the record (when all fields present), then we must be dealing 
      ** with a corrupt database.


      */
      if( (zHdr > zEndHdr)

       || (offset > pC->payloadSize)
       || (zHdr==zEndHdr && offset!=pC->payloadSize)
      ){
        rc = SQLITE_CORRUPT_BKPT;
        goto op_column_error;
      }
    }

    /* If after trying to extra new entries from the header, nHdrParsed is
................................................................................
        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( VdbeMemDynamic(pDest) ) sqlite3VdbeMemSetNull(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 */
    sqlite3VdbeSerialGet(pC->aRow+aOffset[p2], aType[p2], pDest);
  }else{
    /* This branch happens only when content is on overflow pages */
    t = aType[p2];
    if( ((pOp->p5 & (OPFLAG_LENGTHARG|OPFLAG_TYPEOFARG))!=0
          && ((t>=12 && (t&1)==0) || (pOp->p5 & OPFLAG_TYPEOFARG)!=0))
     || (len = sqlite3VdbeSerialTypeLen(t))==0
    ){
      /* Content is irrelevant for
      **    1. the typeof() function,
      **    2. the length(X) function if X is a blob, and
................................................................................
      sqlite3VdbeSerialGet((const u8*)pDest->z, t, pDest);
      pDest->flags &= ~MEM_Ephem;
    }
  }
  pDest->enc = encoding;

op_column_out:
  Deephemeralize(pDest);














op_column_error:
  UPDATE_MAX_BLOBSIZE(pDest);
  REGISTER_TRACE(pOp->p3, pDest);
  break;
}

/* Opcode: Affinity P1 P2 * P4 *
................................................................................

  /* 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{
    assert( memIsValid(pRec) );
    serial_type = sqlite3VdbeSerialType(pRec, file_format);
    len = sqlite3VdbeSerialTypeLen(serial_type);
    if( pRec->flags & MEM_Zero ){
      if( nData ){
        sqlite3VdbeMemExpandBlob(pRec);
      }else{
        nZero += pRec->u.nZero;
        len -= pRec->u.nZero;
................................................................................
  if( nByte>db->aLimit[SQLITE_LIMIT_LENGTH] ){
    goto too_big;
  }

  /* Make sure the output register has a buffer large enough to store 
  ** the new record. The output register (pOp->p3) is not allowed to
  ** be one of the input registers (because the following call to
  ** sqlite3VdbeMemGrow() could clobber the value before it is used).
  */
  if( sqlite3VdbeMemGrow(pOut, (int)nByte, 0) ){
    goto no_mem;
  }
  zNewRecord = (u8 *)pOut->z;

  /* Write the record */
  i = putVarint32(zNewRecord, nHdr);
  j = nHdr;
  assert( pData0<=pLast );
  pRec = pData0;
  do{
    serial_type = sqlite3VdbeSerialType(pRec, file_format);
    i += putVarint32(&zNewRecord[i], serial_type);            /* serial type */
    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) );
................................................................................
  pCur->isOrdered = 1;
  pCur->pgnoRoot = p2;
  rc = sqlite3BtreeCursor(pX, p2, wrFlag, pKeyInfo, pCur->pCursor);
  pCur->pKeyInfo = pKeyInfo;
  assert( OPFLAG_BULKCSR==BTREE_BULKLOAD );
  sqlite3BtreeCursorHints(pCur->pCursor, (pOp->p5 & OPFLAG_BULKCSR));

  /* Since it performs no memory allocation or IO, the only value that
  ** sqlite3BtreeCursor() may return is SQLITE_OK. */
  assert( rc==SQLITE_OK );

  /* Set the VdbeCursor.isTable variable. Previous versions of
  ** SQLite used to check if the root-page flags were sane at this point
  ** and report database corruption if they were not, but this check has
  ** since moved into the btree layer.  */  
  pCur->isTable = pOp->p4type!=P4_KEYINFO;
  break;
}
................................................................................
  pC->seekOp = pOp->opcode;
#endif
  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 convert it. */
    pIn3 = &aMem[pOp->p3];
    if( (pIn3->flags & (MEM_Int|MEM_Real))==0 ){
      applyNumericAffinity(pIn3, 0);
    }
    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 */
................................................................................
      /* 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;

................................................................................
    { 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);
    }
  }
................................................................................
  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );
  assert( pC->pCursor!=0 );
  assert( pC->isTable );
  pC->nullRow = 0;
  pIn2 = &aMem[pOp->p2];
  pC->movetoTarget = sqlite3VdbeIntValue(pIn2);
  pC->rowidIsValid = 0;
  pC->deferredMoveto = 1;
  break;
}
  

/* Opcode: Found P1 P2 P3 P4 *
** Synopsis: key=r[P3@P4]
................................................................................
  assert( pC->isTable );
  assert( pC->pseudoTableReg==0 );
  pCrsr = pC->pCursor;
  assert( pCrsr!=0 );
  res = 0;
  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;
}

/* Opcode: Sequence P1 P2 * * *
** Synopsis: r[P2]=cursor[P1].ctr++
................................................................................
    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. */
      /* on the first attempt, simply do one more than previous */
      v = lastRowid;
      v &= (MAX_ROWID>>1); /* ensure doesn't go negative */
      v++; /* ensure non-zero */
      cnt = 0;



      while(   ((rc = sqlite3BtreeMovetoUnpacked(pC->pCursor, 0, (u64)v,
                                                 0, &res))==SQLITE_OK)
            && (res==0)
            && (++cnt<100)){
        /* collision - try another random rowid */
        sqlite3_randomness(sizeof(v), &v);
        if( cnt<5 ){
          /* try "small" random rowids for the initial attempts */
          v &= 0xffffff;
        }else{
          v &= (MAX_ROWID>>1); /* ensure doesn't go negative */
        }
        v++; /* ensure non-zero */
      }
      if( rc==SQLITE_OK && res==0 ){
        rc = SQLITE_FULL;   /* IMP: R-38219-53002 */
        goto abort_due_to_error;
      }
      assert( v>0 );  /* EV: R-40812-03570 */
    }
    pC->rowidIsValid = 0;
    pC->deferredMoveto = 0;
    pC->cacheStatus = CACHE_STALE;
  }
  pOut->u.i = v;
  break;
}

................................................................................
  }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;

  /* Invoke the update-hook if required. */
  if( rc==SQLITE_OK && db->xUpdateCallback && pOp->p4.z ){
    zDb = db->aDb[pC->iDb].zName;
    zTbl = pOp->p4.z;
................................................................................
**
** If P4 is not NULL, then it is the name of the table that P1 is
** pointing to.  The update hook will be invoked, if it exists.
** If P4 is not NULL then the P1 cursor must have been positioned
** using OP_NotFound prior to invoking this opcode.
*/
case OP_Delete: {
  i64 iKey;
  VdbeCursor *pC;

  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );
  assert( pC->pCursor!=0 );  /* Only valid for real tables, no pseudotables */
  iKey = pC->lastRowid;      /* Only used for the update hook */

  /* The OP_Delete opcode always follows an OP_NotExists or OP_Last or
  ** OP_Column on the same table without any intervening operations that
  ** might move or invalidate the cursor.  Hence cursor pC is always pointing
  ** to the row to be deleted and the sqlite3VdbeCursorMoveto() operation
  ** 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);
    assert( pC->iDb>=0 );
  }
  if( pOp->p2 & OPFLAG_NCHANGE ) p->nChange++;
  break;
}
/* Opcode: ResetCount * * * * *
**
................................................................................
  VdbeBranchTaken(res!=0,2);
  if( res ){
    pc = pOp->p2-1;
  }
  break;
};

/* Opcode: SorterData P1 P2 * * *
** Synopsis: r[P2]=data
**
** Write into register P2 the current sorter data for sorter cursor P1.







*/
case OP_SorterData: {
  VdbeCursor *pC;

  pOut = &aMem[pOp->p2];
  pC = p->apCsr[pOp->p1];
  assert( isSorter(pC) );
  rc = sqlite3VdbeSorterRowkey(pC, pOut);
  assert( rc!=SQLITE_OK || (pOut->flags & MEM_Blob) );


  break;
}

/* Opcode: RowData P1 P2 * * *
** Synopsis: r[P2]=data
**
** Write into register P2 the complete row data for cursor P1.
................................................................................
  assert( pC->isTable || pOp->opcode!=OP_RowData );
  assert( pC->isTable==0 || pOp->opcode==OP_RowData );
  assert( pC!=0 );
  assert( pC->nullRow==0 );
  assert( pC->pseudoTableReg==0 );
  assert( pC->pCursor!=0 );
  pCrsr = pC->pCursor;
  assert( sqlite3BtreeCursorIsValid(pCrsr) );

  /* The OP_RowKey and OP_RowData opcodes always follow OP_NotExists or
  ** OP_Rewind/Op_Next with no intervening instructions that might invalidate



  ** the cursor.  Hence the following sqlite3VdbeCursorMoveto() call is always
  ** a no-op and can never fail.  But we leave it in place as a safety.
  */
  assert( pC->deferredMoveto==0 );


  rc = sqlite3VdbeCursorMoveto(pC);
  if( NEVER(rc!=SQLITE_OK) ) goto abort_due_to_error;


  if( pC->isTable==0 ){
    assert( !pC->isTable );
    VVA_ONLY(rc =) sqlite3BtreeKeySize(pCrsr, &n64);
    assert( rc==SQLITE_OK );    /* True because of CursorMoveto() call above */
    if( n64>db->aLimit[SQLITE_LIMIT_LENGTH] ){
      goto too_big;
................................................................................
  }else{
    VVA_ONLY(rc =) sqlite3BtreeDataSize(pCrsr, &n);
    assert( rc==SQLITE_OK );    /* DataSize() cannot fail */
    if( n>(u32)db->aLimit[SQLITE_LIMIT_LENGTH] ){
      goto too_big;
    }
  }

  if( sqlite3VdbeMemGrow(pOut, n, 0) ){
    goto no_mem;
  }
  pOut->n = n;
  MemSetTypeFlag(pOut, MEM_Blob);
  if( pC->isTable==0 ){
    rc = sqlite3BtreeKey(pCrsr, 0, n, pOut->z);
  }else{
................................................................................
    pModule = pVtab->pModule;
    assert( pModule->xRowid );
    rc = pModule->xRowid(pC->pVtabCursor, &v);
    sqlite3VtabImportErrmsg(p, pVtab);
#endif /* SQLITE_OMIT_VIRTUALTABLE */
  }else{
    assert( pC->pCursor!=0 );
    rc = sqlite3VdbeCursorMoveto(pC);
    if( rc ) goto abort_due_to_error;
    if( pC->rowidIsValid ){
      v = pC->lastRowid;
    }else{
      rc = sqlite3BtreeKeySize(pC->pCursor, &v);
      assert( rc==SQLITE_OK );  /* Always so because of CursorMoveto() above */
    }
  }
  pOut->u.i = v;
  break;
}

/* Opcode: NullRow P1 * * * *
**
................................................................................
case OP_NullRow: {
  VdbeCursor *pC;

  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );
  pC->nullRow = 1;
  pC->rowidIsValid = 0;
  pC->cacheStatus = CACHE_STALE;
  if( pC->pCursor ){
    sqlite3BtreeClearCursor(pC->pCursor);
  }
  break;
}

................................................................................
  assert( pC!=0 );
  pCrsr = pC->pCursor;
  res = 0;
  assert( pCrsr!=0 );
  rc = sqlite3BtreeLast(pCrsr, &res);
  pC->nullRow = (u8)res;
  pC->deferredMoveto = 0;
  pC->rowidIsValid = 0;
  pC->cacheStatus = CACHE_STALE;
#ifdef SQLITE_DEBUG
  pC->seekOp = OP_Last;
#endif
  if( pOp->p2>0 ){
    VdbeBranchTaken(res!=0,2);
    if( res ) pc = pOp->p2 - 1;
................................................................................
    rc = sqlite3VdbeSorterRewind(pC, &res);
  }else{
    pCrsr = pC->pCursor;
    assert( pCrsr );
    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;
  }
................................................................................
    p->aCounter[pOp->p5]++;
#ifdef SQLITE_TEST
    sqlite3_search_count++;
#endif
  }else{
    pC->nullRow = 1;
  }
  pC->rowidIsValid = 0;
  goto check_for_interrupt;
}

/* Opcode: IdxInsert P1 P2 P3 * P5
** Synopsis: key=r[P2]
**
** Register P2 holds an SQL index key made using the
................................................................................

  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );
  pCrsr = pC->pCursor;
  assert( pCrsr!=0 );
  pOut->flags = MEM_Null;







  rc = sqlite3VdbeCursorMoveto(pC);
  if( NEVER(rc) ) goto abort_due_to_error;
  assert( pC->deferredMoveto==0 );
  assert( pC->isTable==0 );

  if( !pC->nullRow ){
    rowid = 0;  /* Not needed.  Only used to silence a warning. */
    rc = sqlite3VdbeIdxRowid(db, pCrsr, &rowid);
    if( rc!=SQLITE_OK ){
      goto abort_due_to_error;
    }
    pOut->u.i = rowid;
................................................................................
  ctx.pFunc = pOp->p4.pFunc;
  assert( pOp->p3>0 && pOp->p3<=(p->nMem-p->nCursor) );
  ctx.pMem = pMem = &aMem[pOp->p3];
  pMem->n++;
  sqlite3VdbeMemInit(&t, db, MEM_Null);
  ctx.pOut = &t;
  ctx.isError = 0;
  ctx.pColl = 0;

  ctx.skipFlag = 0;
  if( ctx.pFunc->funcFlags & SQLITE_FUNC_NEEDCOLL ){
    assert( pOp>p->aOp );
    assert( pOp[-1].p4type==P4_COLLSEQ );
    assert( pOp[-1].opcode==OP_CollSeq );
    ctx.pColl = pOp[-1].p4.pColl;
  }
  (ctx.pFunc->xStep)(&ctx, n, apVal); /* IMP: R-24505-23230 */
  if( ctx.isError ){
    sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3_value_text(&t));
    rc = ctx.isError;
  }
  if( ctx.skipFlag ){
    assert( pOp[-1].opcode==OP_CollSeq );

      (isBtreeCursor?sqlite3BtreeCursorSize():0);

  assert( iCur<p->nCursor );
  if( p->apCsr[iCur] ){
    sqlite3VdbeFreeCursor(p, p->apCsr[iCur]);
    p->apCsr[iCur] = 0;
  }
  if( SQLITE_OK==sqlite3VdbeMemClearAndResize(pMem, nByte) ){
    p->apCsr[iCur] = pCx = (VdbeCursor*)pMem->z;
    memset(pCx, 0, sizeof(VdbeCursor));
    pCx->iDb = iDb;
    pCx->nField = nField;
    pCx->aOffset = &pCx->aType[nField];
    if( isBtreeCursor ){
      pCx->pCursor = (BtCursor*)
          &pMem->z[ROUND8(sizeof(VdbeCursor))+2*sizeof(u32)*nField];
      sqlite3BtreeCursorZero(pCx->pCursor);
    }
  }
  return pCx;
................................................................................
** point or exponential notation, the result is only MEM_Real, even
** if there is an exact integer representation of the quantity.
*/
static void applyNumericAffinity(Mem *pRec, int bTryForInt){
  double rValue;
  i64 iValue;
  u8 enc = pRec->enc;
  assert( (pRec->flags & (MEM_Str|MEM_Int|MEM_Real))==MEM_Str );
  if( sqlite3AtoF(pRec->z, &rValue, pRec->n, enc)==0 ) return;
  if( 0==sqlite3Atoi64(pRec->z, &iValue, pRec->n, enc) ){
    pRec->u.i = iValue;
    pRec->flags |= MEM_Int;
  }else{
    pRec->u.r = rValue;
    pRec->flags |= MEM_Real;
    if( bTryForInt ) sqlite3VdbeIntegerAffinity(pRec);
  }
}

/*
** Processing is determine by the affinity parameter:
................................................................................
**    No-op.  pRec is unchanged.
*/
static void applyAffinity(
  Mem *pRec,          /* The value to apply affinity to */
  char affinity,      /* The affinity to be applied */
  u8 enc              /* Use this text encoding */
){
  if( affinity>=SQLITE_AFF_NUMERIC ){
    assert( affinity==SQLITE_AFF_INTEGER || affinity==SQLITE_AFF_REAL
             || affinity==SQLITE_AFF_NUMERIC );
    if( (pRec->flags & MEM_Int)==0 ){
      if( (pRec->flags & MEM_Real)==0 ){
        if( pRec->flags & MEM_Str ) applyNumericAffinity(pRec,1);
      }else{
        sqlite3VdbeIntegerAffinity(pRec);
      }
    }
  }else if( affinity==SQLITE_AFF_TEXT ){
    /* Only attempt the conversion to TEXT if there is an integer or real
    ** representation (blob and NULL do not get converted) but no string
    ** representation.
    */
    if( 0==(pRec->flags&MEM_Str) && (pRec->flags&(MEM_Real|MEM_Int)) ){
      sqlite3VdbeMemStringify(pRec, enc, 1);
    }










  }
}

/*
** 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
................................................................................
){
  applyAffinity((Mem *)pVal, affinity, enc);
}

/*
** pMem currently only holds a string type (or maybe a BLOB that we can
** interpret as a string if we want to).  Compute its corresponding
** numeric type, if has one.  Set the pMem->u.r and pMem->u.i fields
** accordingly.
*/
static u16 SQLITE_NOINLINE computeNumericType(Mem *pMem){
  assert( (pMem->flags & (MEM_Int|MEM_Real))==0 );
  assert( (pMem->flags & (MEM_Str|MEM_Blob))!=0 );
  if( sqlite3AtoF(pMem->z, &pMem->u.r, pMem->n, pMem->enc)==0 ){
    return 0;
  }
  if( sqlite3Atoi64(pMem->z, &pMem->u.i, pMem->n, pMem->enc)==SQLITE_OK ){
    return MEM_Int;
  }
  return MEM_Real;
}

/*
** Return the numeric type for pMem, either MEM_Int or MEM_Real or both or
** none.  
**
** Unlike applyNumericAffinity(), this routine does not modify pMem->flags.
** But it does set pMem->u.r and pMem->u.i appropriately.
*/
static u16 numericType(Mem *pMem){
  if( pMem->flags & (MEM_Int|MEM_Real) ){
    return pMem->flags & (MEM_Int|MEM_Real);
  }
  if( pMem->flags & (MEM_Str|MEM_Blob) ){
    return computeNumericType(pMem);
................................................................................
    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);
#ifndef SQLITE_OMIT_FLOATING_POINT
  }else if( p->flags & MEM_Real ){
    printf(" r:%g", p->u.r);
#endif
  }else if( p->flags & MEM_RowSet ){
    printf(" (rowset)");
  }else{
    char zBuf[200];
    sqlite3VdbeMemPrettyPrint(p, zBuf);
    printf(" %s", zBuf);
................................................................................
**
** P4 is a pointer to a 64-bit floating point value.
** Write that value into register P2.
*/
case OP_Real: {            /* same as TK_FLOAT, out2-prerelease */
  pOut->flags = MEM_Real;
  assert( !sqlite3IsNaN(*pOp->p4.pReal) );
  pOut->u.r = *pOp->p4.pReal;
  break;
}
#endif

/* Opcode: String8 * P2 * P4 *
** Synopsis: r[P2]='P4'
**
................................................................................
  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->szMalloc>0 && pOut->zMalloc==pOut->z );
    assert( VdbeMemDynamic(pOut)==0 );
    pOut->szMalloc = 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;
................................................................................
** Move the P3 values in register P1..P1+P3-1 over into
** registers P2..P2+P3-1.  Registers P1..P1+P3-1 are
** left holding a NULL.  It is an error for register ranges
** P1..P1+P3-1 and P2..P2+P3-1 to overlap.  It is an error
** for P3 to be less than 1.
*/
case OP_Move: {

  int n;           /* Number of registers left to copy */
  int p1;          /* Register to copy from */
  int p2;          /* Register to copy to */

  n = pOp->p3;
  p1 = pOp->p1;
  p2 = pOp->p2;
................................................................................
  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);
    sqlite3VdbeMemMove(pOut, pIn1);


#ifdef SQLITE_DEBUG
    if( pOut->pScopyFrom>=&aMem[p1] && pOut->pScopyFrom<&aMem[p1+pOp->p3] ){
      pOut->pScopyFrom += p1 - pOp->p2;
    }
#endif


    REGISTER_TRACE(p2++, pOut);
    pIn1++;
    pOut++;
  }while( --n );
  break;
}

................................................................................
#ifdef SQLITE_OMIT_FLOATING_POINT
    pOut->u.i = rB;
    MemSetTypeFlag(pOut, MEM_Int);
#else
    if( sqlite3IsNaN(rB) ){
      goto arithmetic_result_is_null;
    }
    pOut->u.r = rB;
    MemSetTypeFlag(pOut, MEM_Real);
    if( ((type1|type2)&MEM_Real)==0 && !bIntint ){
      sqlite3VdbeIntegerAffinity(pOut);
    }
#endif
  }
  break;
................................................................................
  }

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

  ctx.fErrorOrAux = 0;






  db->lastRowid = lastRowid;
  (*ctx.pFunc->xFunc)(&ctx, n, apVal); /* IMP: R-24505-23230 */
  lastRowid = db->lastRowid;  /* Remember rowid changes made by xFunc */

  /* If the function returned an error, throw an exception */
  if( ctx.fErrorOrAux ){
    if( ctx.isError ){
      sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3_value_text(ctx.pOut));
      rc = ctx.isError;
    }
................................................................................
** <li value="100"> INTEGER
** <li value="101"> REAL
** </ul>
**
** A NULL value is not changed by this routine.  It remains NULL.
*/
case OP_Cast: {                  /* in1 */
  assert( pOp->p2>=SQLITE_AFF_NONE && pOp->p2<=SQLITE_AFF_REAL );
  testcase( pOp->p2==SQLITE_AFF_TEXT );
  testcase( pOp->p2==SQLITE_AFF_NONE );
  testcase( pOp->p2==SQLITE_AFF_NUMERIC );
  testcase( pOp->p2==SQLITE_AFF_INTEGER );
  testcase( pOp->p2==SQLITE_AFF_REAL );
  pIn1 = &aMem[pOp->p1];
  memAboutToChange(p, pIn1);
................................................................................
        }
      }
      break;
    }
  }else{
    /* Neither operand is NULL.  Do a comparison. */
    affinity = pOp->p5 & SQLITE_AFF_MASK;
    if( affinity>=SQLITE_AFF_NUMERIC ){
      if( (pIn1->flags & (MEM_Int|MEM_Real|MEM_Str))==MEM_Str ){
        applyNumericAffinity(pIn1,0);
      }
      if( (pIn3->flags & (MEM_Int|MEM_Real|MEM_Str))==MEM_Str ){
        applyNumericAffinity(pIn3,0);

      }
    }else if( affinity==SQLITE_AFF_TEXT ){
      if( (pIn1->flags & MEM_Str)==0 && (pIn1->flags & (MEM_Int|MEM_Real))!=0 ){
        testcase( pIn1->flags & MEM_Int );
        testcase( pIn1->flags & MEM_Real );
        sqlite3VdbeMemStringify(pIn1, encoding, 1);
      }
      if( (pIn3->flags & MEM_Str)==0 && (pIn3->flags & (MEM_Int|MEM_Real))!=0 ){
        testcase( pIn3->flags & MEM_Int );
        testcase( pIn3->flags & MEM_Real );
        sqlite3VdbeMemStringify(pIn3, encoding, 1);
      }
    }
    assert( pOp->p4type==P4_COLLSEQ || pOp->p4.pColl==0 );
    if( pIn1->flags & MEM_Zero ){
      sqlite3VdbeMemExpandBlob(pIn1);
      flags1 &= ~MEM_Zero;
    }
    if( pIn3->flags & MEM_Zero ){
      sqlite3VdbeMemExpandBlob(pIn3);
      flags3 &= ~MEM_Zero;
    }
    if( db->mallocFailed ) goto no_mem;
    res = sqlite3MemCompare(pIn3, pIn1, pOp->p4.pColl);
  }
  switch( pOp->opcode ){
    case OP_Eq:    res = res==0;     break;
    case OP_Ne:    res = res!=0;     break;
    case OP_Lt:    res = res<0;      break;
    case OP_Le:    res = res<=0;     break;
................................................................................
** skipped for length() and all content loading can be skipped for typeof().
*/
case OP_Column: {
  i64 payloadSize64; /* Number of bytes in the record */
  int p2;            /* column number to retrieve */
  VdbeCursor *pC;    /* The VDBE cursor */
  BtCursor *pCrsr;   /* The BTree cursor */

  u32 *aOffset;      /* aOffset[i] is offset to start of data for i-th column */
  int len;           /* The length of the serialized data for the column */
  int i;             /* Loop counter */
  Mem *pDest;        /* Where to write the extracted value */
  Mem sMem;          /* For storing the record being decoded */
  const u8 *zData;   /* Part of the record being decoded */
  const u8 *zHdr;    /* Next unparsed byte of the header */
  const u8 *zEndHdr; /* Pointer to first byte after the header */
  u32 offset;        /* Offset into the data */
  u32 szField;       /* Number of bytes in the content of a field */
  u32 avail;         /* Number of bytes of available data */
  u32 t;             /* A type code from the record header */
  u16 fx;            /* pDest->flags value */
  Mem *pReg;         /* PseudoTable input register */

  p2 = pOp->p2;
  assert( pOp->p3>0 && pOp->p3<=(p->nMem-p->nCursor) );
  pDest = &aMem[pOp->p3];
  memAboutToChange(p, pDest);
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );
  assert( p2<pC->nField );
  aOffset = pC->aOffset;

#ifndef SQLITE_OMIT_VIRTUALTABLE
  assert( pC->pVtabCursor==0 ); /* OP_Column never called on virtual table */
#endif
  pCrsr = pC->pCursor;
  assert( pCrsr!=0 || pC->pseudoTableReg>0 ); /* pCrsr NULL on PseudoTables */
  assert( pCrsr!=0 || pC->nullRow );          /* pC->nullRow on PseudoTables */

  /* If the cursor cache is stale, bring it up-to-date */
  rc = sqlite3VdbeCursorMoveto(pC);
  if( rc ) goto abort_due_to_error;
  if( pC->cacheStatus!=p->cacheCtr ){
    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;
................................................................................
        goto too_big;
      }
    }
    pC->cacheStatus = p->cacheCtr;
    pC->iHdrOffset = getVarint32(pC->aRow, offset);
    pC->nHdrParsed = 0;
    aOffset[0] = offset;









    /* Make sure a corrupt database has not given us an oversize header.
    ** Do this now to avoid an oversize memory allocation.
    **
    ** Type entries can be between 1 and 5 bytes each.  But 4 and 5 byte
    ** types use so much data space that there can only be 4096 and 32 of
    ** them, respectively.  So the maximum header length results from a
................................................................................
    ** 3-byte type for each of the maximum of 32768 columns plus three
    ** extra bytes for the header length itself.  32768*3 + 3 = 98307.
    */
    if( offset > 98307 || offset > pC->payloadSize ){
      rc = SQLITE_CORRUPT_BKPT;
      goto op_column_error;
    }

    if( avail<offset ){
      /* pC->aRow does not have to hold the entire row, but it does at least
      ** need to cover the header of the record.  If pC->aRow does not contain
      ** the complete header, then set it to zero, forcing the header to be
      ** dynamically allocated. */
      pC->aRow = 0;
      pC->szRow = 0;
    }

    /* The following goto is an optimization.  It can be omitted and
    ** everything will still work.  But OP_Column is measurably faster
    ** by skipping the subsequent conditional, which is always true.
    */
    assert( pC->nHdrParsed<=p2 );         /* Conditional skipped */
    goto op_column_read_header;
  }

  /* Make sure at least the first p2+1 entries of the header have been
  ** parsed and valid information is in aOffset[] and pC->aType[].
  */
  if( pC->nHdrParsed<=p2 ){
    /* If there is more header available for parsing in the record, try
    ** to extract additional fields up through the p2+1-th field 
    */
    op_column_read_header:
    if( pC->iHdrOffset<aOffset[0] ){
      /* Make sure zData points to enough of the record to cover the header. */
      if( pC->aRow==0 ){
        memset(&sMem, 0, sizeof(sMem));
        rc = sqlite3VdbeMemFromBtree(pCrsr, 0, aOffset[0], 
                                     !pC->isTable, &sMem);
        if( rc!=SQLITE_OK ){
................................................................................
          goto op_column_error;
        }
        zData = (u8*)sMem.z;
      }else{
        zData = pC->aRow;
      }
  
      /* Fill in pC->aType[i] and aOffset[i] values through the p2-th field. */
      i = pC->nHdrParsed;
      offset = aOffset[i];
      zHdr = zData + pC->iHdrOffset;
      zEndHdr = zData + aOffset[0];
      assert( i<=p2 && zHdr<zEndHdr );
      do{
        if( zHdr[0]<0x80 ){
          t = zHdr[0];
          zHdr++;
        }else{
          zHdr += sqlite3GetVarint32(zHdr, &t);
        }
        pC->aType[i] = t;
        szField = sqlite3VdbeSerialTypeLen(t);
        offset += szField;
        if( offset<szField ){  /* True if offset overflows */
          zHdr = &zEndHdr[1];  /* Forces SQLITE_CORRUPT return below */
          break;
        }
        i++;
................................................................................
      pC->nHdrParsed = i;
      pC->iHdrOffset = (u32)(zHdr - zData);
      if( pC->aRow==0 ){
        sqlite3VdbeMemRelease(&sMem);
        sMem.flags = MEM_Null;
      }
  
      /* The record is corrupt if any of the following are true:
      ** (1) the bytes of the header extend past the declared header size
      **          (zHdr>zEndHdr)
      ** (2) the entire header was used but not all data was used
      **          (zHdr==zEndHdr && offset!=pC->payloadSize)
      ** (3) the end of the data extends beyond the end of the record.
      **          (offset > pC->payloadSize)
      */

      if( (zHdr>=zEndHdr && (zHdr>zEndHdr || offset!=pC->payloadSize))
       || (offset > pC->payloadSize)

      ){
        rc = SQLITE_CORRUPT_BKPT;
        goto op_column_error;
      }
    }

    /* If after trying to extra new entries from the header, nHdrParsed is
................................................................................
        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 pC->aType[p2] are
  ** all valid.
  */
  assert( p2<pC->nHdrParsed );
  assert( rc==SQLITE_OK );
  assert( sqlite3VdbeCheckMemInvariants(pDest) );
  if( VdbeMemDynamic(pDest) ) sqlite3VdbeMemSetNull(pDest);
  t = pC->aType[p2];
  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 */
    sqlite3VdbeSerialGet(pC->aRow+aOffset[p2], t, pDest);
  }else{
    /* This branch happens only when content is on overflow pages */

    if( ((pOp->p5 & (OPFLAG_LENGTHARG|OPFLAG_TYPEOFARG))!=0
          && ((t>=12 && (t&1)==0) || (pOp->p5 & OPFLAG_TYPEOFARG)!=0))
     || (len = sqlite3VdbeSerialTypeLen(t))==0
    ){
      /* Content is irrelevant for
      **    1. the typeof() function,
      **    2. the length(X) function if X is a blob, and
................................................................................
      sqlite3VdbeSerialGet((const u8*)pDest->z, t, pDest);
      pDest->flags &= ~MEM_Ephem;
    }
  }
  pDest->enc = encoding;

op_column_out:
  /* If the column value is an ephemeral string, go ahead and persist
  ** that string in case the cursor moves before the column value is
  ** used.  The following code does the equivalent of Deephemeralize()
  ** but does it faster. */
  if( (pDest->flags & MEM_Ephem)!=0 && pDest->z ){
    fx = pDest->flags & (MEM_Str|MEM_Blob);
    assert( fx!=0 );
    zData = (const u8*)pDest->z;
    len = pDest->n;
    if( sqlite3VdbeMemClearAndResize(pDest, len+2) ) goto no_mem;
    memcpy(pDest->z, zData, len);
    pDest->z[len] = 0;
    pDest->z[len+1] = 0;
    pDest->flags = fx|MEM_Term;
  }
op_column_error:
  UPDATE_MAX_BLOBSIZE(pDest);
  REGISTER_TRACE(pOp->p3, pDest);
  break;
}

/* Opcode: Affinity P1 P2 * P4 *
................................................................................

  /* 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{
    assert( memIsValid(pRec) );
    pRec->uTemp = serial_type = sqlite3VdbeSerialType(pRec, file_format);
    len = sqlite3VdbeSerialTypeLen(serial_type);
    if( pRec->flags & MEM_Zero ){
      if( nData ){
        sqlite3VdbeMemExpandBlob(pRec);
      }else{
        nZero += pRec->u.nZero;
        len -= pRec->u.nZero;
................................................................................
  if( nByte>db->aLimit[SQLITE_LIMIT_LENGTH] ){
    goto too_big;
  }

  /* Make sure the output register has a buffer large enough to store 
  ** the new record. The output register (pOp->p3) is not allowed to
  ** be one of the input registers (because the following call to
  ** sqlite3VdbeMemClearAndResize() could clobber the value before it is used).
  */
  if( sqlite3VdbeMemClearAndResize(pOut, (int)nByte) ){
    goto no_mem;
  }
  zNewRecord = (u8 *)pOut->z;

  /* Write the record */
  i = putVarint32(zNewRecord, nHdr);
  j = nHdr;
  assert( pData0<=pLast );
  pRec = pData0;
  do{
    serial_type = pRec->uTemp;
    i += putVarint32(&zNewRecord[i], serial_type);            /* serial type */
    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) );
................................................................................
  pCur->isOrdered = 1;
  pCur->pgnoRoot = p2;
  rc = sqlite3BtreeCursor(pX, p2, wrFlag, pKeyInfo, pCur->pCursor);
  pCur->pKeyInfo = pKeyInfo;
  assert( OPFLAG_BULKCSR==BTREE_BULKLOAD );
  sqlite3BtreeCursorHints(pCur->pCursor, (pOp->p5 & OPFLAG_BULKCSR));





  /* Set the VdbeCursor.isTable variable. Previous versions of
  ** SQLite used to check if the root-page flags were sane at this point
  ** and report database corruption if they were not, but this check has
  ** since moved into the btree layer.  */  
  pCur->isTable = pOp->p4type!=P4_KEYINFO;
  break;
}
................................................................................
  pC->seekOp = pOp->opcode;
#endif
  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 convert it. */
    pIn3 = &aMem[pOp->p3];
    if( (pIn3->flags & (MEM_Int|MEM_Real|MEM_Str))==MEM_Str ){
      applyNumericAffinity(pIn3, 0);
    }
    iKey = sqlite3VdbeIntValue(pIn3);


    /* 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 */
................................................................................
      /* 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->u.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->u.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);
    pC->movetoTarget = iKey;  /* Used by OP_Delete */
    if( rc!=SQLITE_OK ){
      goto abort_due_to_error;
    }




  }else{
    nField = pOp->p4.i;
    assert( pOp->p4type==P4_INT32 );
    assert( nField>0 );
    r.pKeyInfo = pC->pKeyInfo;
    r.nField = (u16)nField;

................................................................................
    { 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->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;

    }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;

    }else{
      /* res might be negative because the table is empty.  Check to
      ** see if this is the case.
      */
      res = sqlite3BtreeEof(pC->pCursor);
    }
  }
................................................................................
  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );
  assert( pC->pCursor!=0 );
  assert( pC->isTable );
  pC->nullRow = 0;
  pIn2 = &aMem[pOp->p2];
  pC->movetoTarget = sqlite3VdbeIntValue(pIn2);

  pC->deferredMoveto = 1;
  break;
}
  

/* Opcode: Found P1 P2 P3 P4 *
** Synopsis: key=r[P3@P4]
................................................................................
  assert( pC->isTable );
  assert( pC->pseudoTableReg==0 );
  pCrsr = pC->pCursor;
  assert( pCrsr!=0 );
  res = 0;
  iKey = pIn3->u.i;
  rc = sqlite3BtreeMovetoUnpacked(pCrsr, 0, iKey, 0, &res);
  pC->movetoTarget = iKey;  /* Used by OP_Delete */

  pC->nullRow = 0;
  pC->cacheStatus = CACHE_STALE;
  pC->deferredMoveto = 0;
  VdbeBranchTaken(res!=0,2);
  if( res!=0 ){
    pc = pOp->p2 - 1;

  }
  pC->seekResult = res;
  break;
}

/* Opcode: Sequence P1 P2 * * *
** Synopsis: r[P2]=cursor[P1].ctr++
................................................................................
    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. */




      cnt = 0;
      do{
        sqlite3_randomness(sizeof(v), &v);
        v &= (MAX_ROWID>>1); v++;  /* Ensure that v is greater than zero */
      }while(  ((rc = sqlite3BtreeMovetoUnpacked(pC->pCursor, 0, (u64)v,
                                                 0, &res))==SQLITE_OK)
            && (res==0)
            && (++cnt<100));










      if( rc==SQLITE_OK && res==0 ){
        rc = SQLITE_FULL;   /* IMP: R-38219-53002 */
        goto abort_due_to_error;
      }
      assert( v>0 );  /* EV: R-40812-03570 */
    }

    pC->deferredMoveto = 0;
    pC->cacheStatus = CACHE_STALE;
  }
  pOut->u.i = v;
  break;
}

................................................................................
  }else{
    nZero = 0;
  }
  rc = sqlite3BtreeInsert(pC->pCursor, 0, iKey,
                          pData->z, pData->n, nZero,
                          (pOp->p5 & OPFLAG_APPEND)!=0, seekResult
  );

  pC->deferredMoveto = 0;
  pC->cacheStatus = CACHE_STALE;

  /* Invoke the update-hook if required. */
  if( rc==SQLITE_OK && db->xUpdateCallback && pOp->p4.z ){
    zDb = db->aDb[pC->iDb].zName;
    zTbl = pOp->p4.z;
................................................................................
**
** If P4 is not NULL, then it is the name of the table that P1 is
** pointing to.  The update hook will be invoked, if it exists.
** If P4 is not NULL then the P1 cursor must have been positioned
** using OP_NotFound prior to invoking this opcode.
*/
case OP_Delete: {

  VdbeCursor *pC;

  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );
  assert( pC->pCursor!=0 );  /* Only valid for real tables, no pseudotables */
  assert( pC->deferredMoveto==0 );

#ifdef SQLITE_DEBUG
  /* The seek operation that positioned the cursor prior to OP_Delete will
  ** have also set the pC->movetoTarget field to the rowid of the row that
  ** is being deleted */
  if( pOp->p4.z && pC->isTable ){
    i64 iKey = 0;

    sqlite3BtreeKeySize(pC->pCursor, &iKey);
    assert( pC->movetoTarget==iKey ); 

  }
#endif
 
  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, pC->movetoTarget);
    assert( pC->iDb>=0 );
  }
  if( pOp->p2 & OPFLAG_NCHANGE ) p->nChange++;
  break;
}
/* Opcode: ResetCount * * * * *
**
................................................................................
  VdbeBranchTaken(res!=0,2);
  if( res ){
    pc = pOp->p2-1;
  }
  break;
};

/* Opcode: SorterData P1 P2 P3 * *
** Synopsis: r[P2]=data
**
** Write into register P2 the current sorter data for sorter cursor P1.
** Then clear the column header cache on cursor P3.
**
** This opcode is normally use to move a record out of the sorter and into
** a register that is the source for a pseudo-table cursor created using
** OpenPseudo.  That pseudo-table cursor is the one that is identified by
** parameter P3.  Clearing the P3 column cache as part of this opcode saves
** us from having to issue a separate NullRow instruction to clear that cache.
*/
case OP_SorterData: {
  VdbeCursor *pC;

  pOut = &aMem[pOp->p2];
  pC = p->apCsr[pOp->p1];
  assert( isSorter(pC) );
  rc = sqlite3VdbeSorterRowkey(pC, pOut);
  assert( rc!=SQLITE_OK || (pOut->flags & MEM_Blob) );
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  p->apCsr[pOp->p3]->cacheStatus = CACHE_STALE;
  break;
}

/* Opcode: RowData P1 P2 * * *
** Synopsis: r[P2]=data
**
** Write into register P2 the complete row data for cursor P1.
................................................................................
  assert( pC->isTable || pOp->opcode!=OP_RowData );
  assert( pC->isTable==0 || pOp->opcode==OP_RowData );
  assert( pC!=0 );
  assert( pC->nullRow==0 );
  assert( pC->pseudoTableReg==0 );
  assert( pC->pCursor!=0 );
  pCrsr = pC->pCursor;


  /* The OP_RowKey and OP_RowData opcodes always follow OP_NotExists or
  ** OP_Rewind/Op_Next with no intervening instructions that might invalidate
  ** the cursor.  If this where not the case, on of the following assert()s
  ** would fail.  Should this ever change (because of changes in the code
  ** generator) then the fix would be to insert a call to
  ** sqlite3VdbeCursorMoveto().

  */
  assert( pC->deferredMoveto==0 );
  assert( sqlite3BtreeCursorIsValid(pCrsr) );
#if 0  /* Not required due to the previous to assert() statements */
  rc = sqlite3VdbeCursorMoveto(pC);
  if( rc!=SQLITE_OK ) goto abort_due_to_error;
#endif

  if( pC->isTable==0 ){
    assert( !pC->isTable );
    VVA_ONLY(rc =) sqlite3BtreeKeySize(pCrsr, &n64);
    assert( rc==SQLITE_OK );    /* True because of CursorMoveto() call above */
    if( n64>db->aLimit[SQLITE_LIMIT_LENGTH] ){
      goto too_big;
................................................................................
  }else{
    VVA_ONLY(rc =) sqlite3BtreeDataSize(pCrsr, &n);
    assert( rc==SQLITE_OK );    /* DataSize() cannot fail */
    if( n>(u32)db->aLimit[SQLITE_LIMIT_LENGTH] ){
      goto too_big;
    }
  }
  testcase( n==0 );
  if( sqlite3VdbeMemClearAndResize(pOut, MAX(n,32)) ){
    goto no_mem;
  }
  pOut->n = n;
  MemSetTypeFlag(pOut, MEM_Blob);
  if( pC->isTable==0 ){
    rc = sqlite3BtreeKey(pCrsr, 0, n, pOut->z);
  }else{
................................................................................
    pModule = pVtab->pModule;
    assert( pModule->xRowid );
    rc = pModule->xRowid(pC->pVtabCursor, &v);
    sqlite3VtabImportErrmsg(p, pVtab);
#endif /* SQLITE_OMIT_VIRTUALTABLE */
  }else{
    assert( pC->pCursor!=0 );
    rc = sqlite3VdbeCursorRestore(pC);
    if( rc ) goto abort_due_to_error;



    rc = sqlite3BtreeKeySize(pC->pCursor, &v);
    assert( rc==SQLITE_OK );  /* Always so because of CursorRestore() above */

  }
  pOut->u.i = v;
  break;
}

/* Opcode: NullRow P1 * * * *
**
................................................................................
case OP_NullRow: {
  VdbeCursor *pC;

  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );
  pC->nullRow = 1;

  pC->cacheStatus = CACHE_STALE;
  if( pC->pCursor ){
    sqlite3BtreeClearCursor(pC->pCursor);
  }
  break;
}

................................................................................
  assert( pC!=0 );
  pCrsr = pC->pCursor;
  res = 0;
  assert( pCrsr!=0 );
  rc = sqlite3BtreeLast(pCrsr, &res);
  pC->nullRow = (u8)res;
  pC->deferredMoveto = 0;

  pC->cacheStatus = CACHE_STALE;
#ifdef SQLITE_DEBUG
  pC->seekOp = OP_Last;
#endif
  if( pOp->p2>0 ){
    VdbeBranchTaken(res!=0,2);
    if( res ) pc = pOp->p2 - 1;
................................................................................
    rc = sqlite3VdbeSorterRewind(pC, &res);
  }else{
    pCrsr = pC->pCursor;
    assert( pCrsr );
    rc = sqlite3BtreeFirst(pCrsr, &res);
    pC->deferredMoveto = 0;
    pC->cacheStatus = CACHE_STALE;

  }
  pC->nullRow = (u8)res;
  assert( pOp->p2>0 && pOp->p2<p->nOp );
  VdbeBranchTaken(res!=0,2);
  if( res ){
    pc = pOp->p2 - 1;
  }
................................................................................
    p->aCounter[pOp->p5]++;
#ifdef SQLITE_TEST
    sqlite3_search_count++;
#endif
  }else{
    pC->nullRow = 1;
  }

  goto check_for_interrupt;
}

/* Opcode: IdxInsert P1 P2 P3 * P5
** Synopsis: key=r[P2]
**
** Register P2 holds an SQL index key made using the
................................................................................

  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );
  pCrsr = pC->pCursor;
  assert( pCrsr!=0 );
  pOut->flags = MEM_Null;
  assert( pC->isTable==0 );
  assert( pC->deferredMoveto==0 );

  /* sqlite3VbeCursorRestore() can only fail if the record has been deleted
  ** out from under the cursor.  That will never happend for an IdxRowid
  ** opcode, hence the NEVER() arround the check of the return value.
  */
  rc = sqlite3VdbeCursorRestore(pC);
  if( NEVER(rc!=SQLITE_OK) ) goto abort_due_to_error;



  if( !pC->nullRow ){
    rowid = 0;  /* Not needed.  Only used to silence a warning. */
    rc = sqlite3VdbeIdxRowid(db, pCrsr, &rowid);
    if( rc!=SQLITE_OK ){
      goto abort_due_to_error;
    }
    pOut->u.i = rowid;
................................................................................
  ctx.pFunc = pOp->p4.pFunc;
  assert( pOp->p3>0 && pOp->p3<=(p->nMem-p->nCursor) );
  ctx.pMem = pMem = &aMem[pOp->p3];
  pMem->n++;
  sqlite3VdbeMemInit(&t, db, MEM_Null);
  ctx.pOut = &t;
  ctx.isError = 0;
  ctx.pVdbe = p;
  ctx.iOp = pc;
  ctx.skipFlag = 0;






  (ctx.pFunc->xStep)(&ctx, n, apVal); /* IMP: R-24505-23230 */
  if( ctx.isError ){
    sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3_value_text(&t));
    rc = ctx.isError;
  }
  if( ctx.skipFlag ){
    assert( pOp[-1].opcode==OP_CollSeq );

  i16 nField;           /* Number of fields in the header */
  u16 nHdrParsed;       /* Number of header fields parsed so far */
#ifdef SQLITE_DEBUG
  u8 seekOp;            /* Most recent seek operation on this cursor */
#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 isEphemeral:1;   /* True for an ephemeral table */
  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 */
  Pgno pgnoRoot;        /* Root page of the open btree cursor */
  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
  ** cursor is currently pointing to.  Only valid if cacheStatus matches
  ** Vdbe.cacheCtr.  Vdbe.cacheCtr will never take on the value of
  ** CACHE_STALE and so setting cacheStatus=CACHE_STALE guarantees that
  ** the cache is out of date.
................................................................................
  ** be NULL.
  */
  u32 cacheStatus;      /* Cache is valid if this matches Vdbe.cacheCtr */
  u32 payloadSize;      /* Total number of bytes in the record */
  u32 szRow;            /* Byte available in aRow */
  u32 iHdrOffset;       /* Offset to next unparsed byte of the header */
  const u8 *aRow;       /* Data for the current row, if all on one page */

  u32 aType[1];         /* Type values for all entries in the record */
  /* 2*nField extra array elements allocated for aType[], beyond the one
  ** static element declared in the structure.  nField total array slots for
  ** aType[] and nField+1 array slots for aOffset[] */
};
typedef struct VdbeCursor VdbeCursor;

................................................................................

/*
** Internally, the vdbe manipulates nearly all SQL values as Mem
** structures. Each Mem struct may cache multiple representations (string,
** integer etc.) of the same value.
*/
struct Mem {
  union {

    i64 i;              /* Integer value used when MEM_Int is set in flags */
    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;
  u16 flags;          /* Some combination of MEM_Null, MEM_Str, MEM_Dyn, etc. */
  u8  enc;            /* SQLITE_UTF8, SQLITE_UTF16BE, SQLITE_UTF16LE */
  int n;              /* Number of characters in string value, excluding '\0' */
  double r;           /* Real value */
  char *z;            /* String or BLOB value */
  char *zMalloc;      /* Dynamic buffer allocated by sqlite3_malloc() */
  /* ShallowCopy only needs to copy the information above */



  sqlite3 *db;        /* The associated database connection */
  void (*xDel)(void*);/* Destructor for Mem.z - only valid if MEM_Dyn */
#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
};
................................................................................
** structure are known.
**
** This structure is defined inside of vdbeInt.h because it uses substructures
** (Mem) which are only defined there.
*/
struct sqlite3_context {
  Mem *pOut;            /* The return value is stored here */
  FuncDef *pFunc;       /* Pointer to function information.  MUST BE FIRST */
  Mem *pMem;            /* Memory cell used to store aggregate context */
  CollSeq *pColl;       /* Collating sequence */
  Vdbe *pVdbe;          /* The VM that owns this context */
  int iOp;              /* Instruction number of OP_Function */
  int isError;          /* Error code returned by the function. */
  u8 skipFlag;          /* Skip skip accumulator loading if true */
  u8 fErrorOrAux;       /* isError!=0 or pVdbe->pAuxData modified */
};

/*
** An Explain object accumulates indented output which is helpful
** in describing recursive data structures.
*/
................................................................................
#endif
  i64 iCurrentTime;       /* Value of julianday('now') for this statement */
  i64 nFkConstraint;      /* Number of imm. FK constraints this VM */
  i64 nStmtDefCons;       /* Number of def. constraints when stmt started */
  i64 nStmtDefImmCons;    /* Number of def. imm constraints when stmt started */
  char *zSql;             /* Text of the SQL statement that generated this */
  void *pFree;            /* Free this when deleting the vdbe */
#ifdef SQLITE_ENABLE_TREE_EXPLAIN
  Explain *pExplain;      /* The explainer */
  char *zExplain;         /* Explanation of data structures */
#endif
  VdbeFrame *pFrame;      /* Parent frame */
  VdbeFrame *pDelFrame;   /* List of frame objects to free on VM reset */
  int nFrame;             /* Number of frames in pFrame list */
  u32 expmask;            /* Binding to these vars invalidates VM */
  SubProgram *pProgram;   /* Linked list of all sub-programs used by VM */
  int nOnceFlag;          /* Size of array aOnceFlag[] */
  u8 *aOnceFlag;          /* Flags for OP_Once */
................................................................................

/*
** Function prototypes
*/
void sqlite3VdbeFreeCursor(Vdbe *, VdbeCursor*);
void sqliteVdbePopStack(Vdbe*,int);
int sqlite3VdbeCursorMoveto(VdbeCursor*);

#if defined(SQLITE_DEBUG) || defined(VDBE_PROFILE)
void sqlite3VdbePrintOp(FILE*, int, Op*);
#endif
u32 sqlite3VdbeSerialTypeLen(u32);
u32 sqlite3VdbeSerialType(Mem*, int);
u32 sqlite3VdbeSerialPut(unsigned char*, Mem*, u32);
u32 sqlite3VdbeSerialGet(const unsigned char*, u32, Mem*);
................................................................................
int sqlite3VdbeMemFromBtree(BtCursor*,u32,u32,int,Mem*);
void sqlite3VdbeMemRelease(Mem *p);
#define VdbeMemDynamic(X)  \
  (((X)->flags&(MEM_Agg|MEM_Dyn|MEM_RowSet|MEM_Frame))!=0)
int sqlite3VdbeMemFinalize(Mem*, FuncDef*);
const char *sqlite3OpcodeName(int);
int sqlite3VdbeMemGrow(Mem *pMem, int n, int preserve);

int sqlite3VdbeCloseStatement(Vdbe *, int);
void sqlite3VdbeFrameDelete(VdbeFrame*);
int sqlite3VdbeFrameRestore(VdbeFrame *);
int sqlite3VdbeTransferError(Vdbe *p);

int sqlite3VdbeSorterInit(sqlite3 *, int, VdbeCursor *);
void sqlite3VdbeSorterReset(sqlite3 *, VdbeSorter *);

  i16 nField;           /* Number of fields in the header */
  u16 nHdrParsed;       /* Number of header fields parsed so far */
#ifdef SQLITE_DEBUG
  u8 seekOp;            /* Most recent seek operation on this cursor */
#endif
  i8 iDb;               /* Index of cursor database in db->aDb[] (or -1) */
  u8 nullRow;           /* True if pointing to a row with no data */

  u8 deferredMoveto;    /* A call to sqlite3BtreeMoveto() is needed */
  Bool isEphemeral:1;   /* True for an ephemeral table */
  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 */
  Pgno pgnoRoot;        /* Root page of the open btree cursor */
  sqlite3_vtab_cursor *pVtabCursor;  /* The cursor for a virtual table */
  i64 seqCount;         /* Sequence counter */
  i64 movetoTarget;     /* Argument to the deferred sqlite3BtreeMoveto() */

  VdbeSorter *pSorter;  /* Sorter object for OP_SorterOpen cursors */

  /* Cached information about the header for the data record that the
  ** cursor is currently pointing to.  Only valid if cacheStatus matches
  ** Vdbe.cacheCtr.  Vdbe.cacheCtr will never take on the value of
  ** CACHE_STALE and so setting cacheStatus=CACHE_STALE guarantees that
  ** the cache is out of date.
................................................................................
  ** be NULL.
  */
  u32 cacheStatus;      /* Cache is valid if this matches Vdbe.cacheCtr */
  u32 payloadSize;      /* Total number of bytes in the record */
  u32 szRow;            /* Byte available in aRow */
  u32 iHdrOffset;       /* Offset to next unparsed byte of the header */
  const u8 *aRow;       /* Data for the current row, if all on one page */
  u32 *aOffset;         /* Pointer to aType[nField] */
  u32 aType[1];         /* Type values for all entries in the record */
  /* 2*nField extra array elements allocated for aType[], beyond the one
  ** static element declared in the structure.  nField total array slots for
  ** aType[] and nField+1 array slots for aOffset[] */
};
typedef struct VdbeCursor VdbeCursor;

................................................................................

/*
** Internally, the vdbe manipulates nearly all SQL values as Mem
** structures. Each Mem struct may cache multiple representations (string,
** integer etc.) of the same value.
*/
struct Mem {
  union MemValue {
    double r;           /* Real value used when MEM_Real is set in flags */
    i64 i;              /* Integer value used when MEM_Int is set in flags */
    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;
  u16 flags;          /* Some combination of MEM_Null, MEM_Str, MEM_Dyn, etc. */
  u8  enc;            /* SQLITE_UTF8, SQLITE_UTF16BE, SQLITE_UTF16LE */
  int n;              /* Number of characters in string value, excluding '\0' */

  char *z;            /* String or BLOB value */

  /* ShallowCopy only needs to copy the information above */
  char *zMalloc;      /* Space to hold MEM_Str or MEM_Blob if szMalloc>0 */
  int szMalloc;       /* Size of the zMalloc allocation */
  u32 uTemp;          /* Transient storage for serial_type in OP_MakeRecord */
  sqlite3 *db;        /* The associated database connection */
  void (*xDel)(void*);/* Destructor for Mem.z - only valid if MEM_Dyn */
#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
};
................................................................................
** structure are known.
**
** This structure is defined inside of vdbeInt.h because it uses substructures
** (Mem) which are only defined there.
*/
struct sqlite3_context {
  Mem *pOut;            /* The return value is stored here */
  FuncDef *pFunc;       /* Pointer to function information */
  Mem *pMem;            /* Memory cell used to store aggregate context */

  Vdbe *pVdbe;          /* The VM that owns this context */
  int iOp;              /* Instruction number of OP_Function */
  int isError;          /* Error code returned by the function. */
  u8 skipFlag;          /* Skip accumulator loading if true */
  u8 fErrorOrAux;       /* isError!=0 or pVdbe->pAuxData modified */
};

/*
** An Explain object accumulates indented output which is helpful
** in describing recursive data structures.
*/
................................................................................
#endif
  i64 iCurrentTime;       /* Value of julianday('now') for this statement */
  i64 nFkConstraint;      /* Number of imm. FK constraints this VM */
  i64 nStmtDefCons;       /* Number of def. constraints when stmt started */
  i64 nStmtDefImmCons;    /* Number of def. imm constraints when stmt started */
  char *zSql;             /* Text of the SQL statement that generated this */
  void *pFree;            /* Free this when deleting the vdbe */




  VdbeFrame *pFrame;      /* Parent frame */
  VdbeFrame *pDelFrame;   /* List of frame objects to free on VM reset */
  int nFrame;             /* Number of frames in pFrame list */
  u32 expmask;            /* Binding to these vars invalidates VM */
  SubProgram *pProgram;   /* Linked list of all sub-programs used by VM */
  int nOnceFlag;          /* Size of array aOnceFlag[] */
  u8 *aOnceFlag;          /* Flags for OP_Once */
................................................................................

/*
** Function prototypes
*/
void sqlite3VdbeFreeCursor(Vdbe *, VdbeCursor*);
void sqliteVdbePopStack(Vdbe*,int);
int sqlite3VdbeCursorMoveto(VdbeCursor*);
int sqlite3VdbeCursorRestore(VdbeCursor*);
#if defined(SQLITE_DEBUG) || defined(VDBE_PROFILE)
void sqlite3VdbePrintOp(FILE*, int, Op*);
#endif
u32 sqlite3VdbeSerialTypeLen(u32);
u32 sqlite3VdbeSerialType(Mem*, int);
u32 sqlite3VdbeSerialPut(unsigned char*, Mem*, u32);
u32 sqlite3VdbeSerialGet(const unsigned char*, u32, Mem*);
................................................................................
int sqlite3VdbeMemFromBtree(BtCursor*,u32,u32,int,Mem*);
void sqlite3VdbeMemRelease(Mem *p);
#define VdbeMemDynamic(X)  \
  (((X)->flags&(MEM_Agg|MEM_Dyn|MEM_RowSet|MEM_Frame))!=0)
int sqlite3VdbeMemFinalize(Mem*, FuncDef*);
const char *sqlite3OpcodeName(int);
int sqlite3VdbeMemGrow(Mem *pMem, int n, int preserve);
int sqlite3VdbeMemClearAndResize(Mem *pMem, int n);
int sqlite3VdbeCloseStatement(Vdbe *, int);
void sqlite3VdbeFrameDelete(VdbeFrame*);
int sqlite3VdbeFrameRestore(VdbeFrame *);
int sqlite3VdbeTransferError(Vdbe *p);

int sqlite3VdbeSorterInit(sqlite3 *, int, VdbeCursor *);
void sqlite3VdbeSorterReset(sqlite3 *, VdbeSorter *);

  const char *z, 
  sqlite3_uint64 n,
  void (*xDel)(void *),
  unsigned char enc
){
  assert( sqlite3_mutex_held(pCtx->pOut->db->mutex) );
  assert( xDel!=SQLITE_DYNAMIC );

  if( n>0x7fffffff ){
    (void)invokeValueDestructor(z, xDel, pCtx);
  }else{
    setResultStrOrError(pCtx, z, (int)n, enc, xDel);
  }
}
#ifndef SQLITE_OMIT_UTF16
................................................................................
static SQLITE_NOINLINE void *createAggContext(sqlite3_context *p, int nByte){
  Mem *pMem = p->pMem;
  assert( (pMem->flags & MEM_Agg)==0 );
  if( nByte<=0 ){
    sqlite3VdbeMemSetNull(pMem);
    pMem->z = 0;
  }else{
    sqlite3VdbeMemGrow(pMem, nByte, 0);
    pMem->flags = MEM_Agg;
    pMem->u.pDef = p->pFunc;
    if( pMem->z ){
      memset(pMem->z, 0, nByte);
    }
  }
  return (void*)pMem->z;
................................................................................
    __attribute__((aligned(8))) 
#endif
    = {
        /* .u          = */ {0},
        /* .flags      = */ MEM_Null,
        /* .enc        = */ 0,
        /* .n          = */ 0,
        /* .r          = */ (double)0,
        /* .z          = */ 0,
        /* .zMalloc    = */ 0,


        /* .db         = */ 0,
        /* .xDel       = */ 0,
#ifdef SQLITE_DEBUG
        /* .pScopyFrom = */ 0,
        /* .pFiller    = */ 0,
#endif
      };
................................................................................
  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;
    }
    case SQLITE_BLOB: {
      if( pValue->flags & MEM_Zero ){
        rc = sqlite3_bind_zeroblob(pStmt, i, pValue->u.nZero);
      }else{
        rc = sqlite3_bind_blob(pStmt, i, pValue->z, pValue->n,SQLITE_TRANSIENT);

  const char *z, 
  sqlite3_uint64 n,
  void (*xDel)(void *),
  unsigned char enc
){
  assert( sqlite3_mutex_held(pCtx->pOut->db->mutex) );
  assert( xDel!=SQLITE_DYNAMIC );
  if( enc==SQLITE_UTF16 ) enc = SQLITE_UTF16NATIVE;
  if( n>0x7fffffff ){
    (void)invokeValueDestructor(z, xDel, pCtx);
  }else{
    setResultStrOrError(pCtx, z, (int)n, enc, xDel);
  }
}
#ifndef SQLITE_OMIT_UTF16
................................................................................
static SQLITE_NOINLINE void *createAggContext(sqlite3_context *p, int nByte){
  Mem *pMem = p->pMem;
  assert( (pMem->flags & MEM_Agg)==0 );
  if( nByte<=0 ){
    sqlite3VdbeMemSetNull(pMem);
    pMem->z = 0;
  }else{
    sqlite3VdbeMemClearAndResize(pMem, nByte);
    pMem->flags = MEM_Agg;
    pMem->u.pDef = p->pFunc;
    if( pMem->z ){
      memset(pMem->z, 0, nByte);
    }
  }
  return (void*)pMem->z;
................................................................................
    __attribute__((aligned(8))) 
#endif
    = {
        /* .u          = */ {0},
        /* .flags      = */ MEM_Null,
        /* .enc        = */ 0,
        /* .n          = */ 0,

        /* .z          = */ 0,
        /* .zMalloc    = */ 0,
        /* .szMalloc   = */ 0,
        /* .iPadding1  = */ 0,
        /* .db         = */ 0,
        /* .xDel       = */ 0,
#ifdef SQLITE_DEBUG
        /* .pScopyFrom = */ 0,
        /* .pFiller    = */ 0,
#endif
      };
................................................................................
  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->u.r);
      break;
    }
    case SQLITE_BLOB: {
      if( pValue->flags & MEM_Zero ){
        rc = sqlite3_bind_zeroblob(pStmt, i, pValue->u.nZero);
      }else{
        rc = sqlite3_bind_blob(pStmt, i, pValue->z, pValue->n,SQLITE_TRANSIENT);

**
**    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 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.
*/
#include "sqliteInt.h"
#include "vdbeInt.h"

/*
** Create a new virtual database engine.
*/
................................................................................
        break;
      }
      case P4_MEM: {
        if( db->pnBytesFreed==0 ){
          sqlite3ValueFree((sqlite3_value*)p4);
        }else{
          Mem *p = (Mem*)p4;
          sqlite3DbFree(db, p->zMalloc);
          sqlite3DbFree(db, p);
        }
        break;
      }
      case P4_VTAB : {
        if( db->pnBytesFreed==0 ) sqlite3VtabUnlock((VTable *)p4);
        break;
................................................................................
    memset(pOp, 0, sizeof(pOp[0]));
    pOp->opcode = OP_Noop;
    if( addr==p->nOp-1 ) p->nOp--;
  }
}

/*
** Remove the last opcode inserted

*/
int sqlite3VdbeDeletePriorOpcode(Vdbe *p, u8 op){
  if( (p->nOp-1)>(p->pParse->iFixedOp) && p->aOp[p->nOp-1].opcode==op ){
    sqlite3VdbeChangeToNoop(p, p->nOp-1);
    return 1;
  }else{
    return 0;
................................................................................
    case P4_MEM: {
      Mem *pMem = pOp->p4.pMem;
      if( pMem->flags & MEM_Str ){
        zP4 = pMem->z;
      }else if( pMem->flags & MEM_Int ){
        sqlite3_snprintf(nTemp, zTemp, "%lld", pMem->u.i);
      }else if( pMem->flags & MEM_Real ){
        sqlite3_snprintf(nTemp, zTemp, "%.16g", pMem->r);
      }else if( pMem->flags & MEM_Null ){
        sqlite3_snprintf(nTemp, zTemp, "NULL");
      }else{
        assert( pMem->flags & MEM_Blob );
        zP4 = "(blob)";
      }
      break;
................................................................................
#endif

/*
** Release an array of N Mem elements
*/
static void releaseMemArray(Mem *p, int N){
  if( p && N ){
    Mem *pEnd;
    sqlite3 *db = p->db;
    u8 malloc_failed = db->mallocFailed;
    if( db->pnBytesFreed ){
      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.
      **
................................................................................
      */
      testcase( p->flags & MEM_Agg );
      testcase( p->flags & MEM_Dyn );
      testcase( p->flags & MEM_Frame );
      testcase( p->flags & MEM_RowSet );
      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
** allocated by the OP_Program opcode in sqlite3VdbeExec().
................................................................................
    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);
................................................................................
      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
................................................................................
  }
#endif
}

/*
** Prepare a virtual machine for execution for the first time after
** creating the virtual machine.  This involves things such
** as allocating stack space and initializing the program counter.
** After the VDBE has be prepped, it can be executed by one or more
** calls to sqlite3VdbeExec().  
**
** This function may be called exactly once on each virtual machine.
** After this routine is called the VM has been "packaged" and is ready
** to run.  After this routine is called, further calls to 
** sqlite3VdbeAddOp() functions are prohibited.  This routine disconnects
................................................................................
    sqlite3BtreeClose(pCx->pBt);
    /* The pCx->pCursor will be close automatically, if it exists, by
    ** the call above. */
  }else if( pCx->pCursor ){
    sqlite3BtreeCloseCursor(pCx->pCursor);
  }
#ifndef SQLITE_OMIT_VIRTUALTABLE
  if( pCx->pVtabCursor ){
    sqlite3_vtab_cursor *pVtabCursor = pCx->pVtabCursor;
    const sqlite3_module *pModule = pVtabCursor->pVtab->pModule;
    p->inVtabMethod = 1;
    pModule->xClose(pVtabCursor);
    p->inVtabMethod = 0;
  }
#endif
................................................................................
** open cursors.
*/
static void closeAllCursors(Vdbe *p){
  if( p->pFrame ){
    VdbeFrame *pFrame;
    for(pFrame=p->pFrame; pFrame->pParent; pFrame=pFrame->pParent);
    sqlite3VdbeFrameRestore(pFrame);
  }
  p->pFrame = 0;
  p->nFrame = 0;



  if( p->apCsr ){
    int i;
    for(i=0; i<p->nCursor; i++){
      VdbeCursor *pC = p->apCsr[i];
      if( pC ){
        sqlite3VdbeFreeCursor(p, pC);
................................................................................
  while( p->pDelFrame ){
    VdbeFrame *pDel = p->pDelFrame;
    p->pDelFrame = pDel->pParent;
    sqlite3VdbeFrameDelete(pDel);
  }

  /* Delete any auxdata allocations made by the VM */
  sqlite3VdbeDeleteAuxData(p, -1, 0);
  assert( p->pAuxData==0 );
}

/*
** Clean up the VM after execution.
**
** This routine will automatically close any cursors, lists, and/or
** sorters that were left open.  It also deletes the values of
** variables in the aVar[] array.
*/
static void Cleanup(Vdbe *p){
  sqlite3 *db = p->db;

#ifdef SQLITE_DEBUG
  /* Execute assert() statements to ensure that the Vdbe.apCsr[] and 
  ** Vdbe.aMem[] arrays have already been cleaned up.  */
................................................................................
    sqlite3DbFree(db, pSub);
  }
  for(i=p->nzVar-1; i>=0; i--) sqlite3DbFree(db, p->azVar[i]);
  vdbeFreeOpArray(db, p->aOp, p->nOp);
  sqlite3DbFree(db, p->aColName);
  sqlite3DbFree(db, p->zSql);
  sqlite3DbFree(db, p->pFree);
#if defined(SQLITE_ENABLE_TREE_EXPLAIN)
  sqlite3DbFree(db, p->zExplain);
  sqlite3DbFree(db, p->pExplain);
#endif
}

/*
** Delete an entire VDBE.
*/
void sqlite3VdbeDelete(Vdbe *p){
  sqlite3 *db;
................................................................................
#ifdef SQLITE_TEST
  extern int sqlite3_search_count;
#endif
  assert( p->deferredMoveto );
  assert( p->isTable );
  rc = sqlite3BtreeMovetoUnpacked(p->pCursor, 0, p->movetoTarget, 0, &res);
  if( rc ) return rc;
  p->lastRowid = p->movetoTarget;
  if( res!=0 ) return SQLITE_CORRUPT_BKPT;
  p->rowidIsValid = 1;
#ifdef SQLITE_TEST
  sqlite3_search_count++;
#endif
  p->deferredMoveto = 0;
  p->cacheStatus = CACHE_STALE;
  return SQLITE_OK;
}
................................................................................
  assert( p->pCursor!=0 );
  assert( sqlite3BtreeCursorHasMoved(p->pCursor) );
  rc = sqlite3BtreeCursorRestore(p->pCursor, &isDifferentRow);
  p->cacheStatus = CACHE_STALE;
  if( isDifferentRow ) p->nullRow = 1;
  return rc;
}












/*
** Make sure the cursor p is ready to read or write the row to which it
** was last positioned.  Return an error code if an OOM fault or I/O error
** prevents us from positioning the cursor to its correct position.
**
** If a MoveTo operation is pending on the given cursor, then do that
................................................................................
** If the cursor is already pointing to the correct row and that row has
** not been deleted out from under the cursor, then this routine is a no-op.
*/
int sqlite3VdbeCursorMoveto(VdbeCursor *p){
  if( p->deferredMoveto ){
    return handleDeferredMoveto(p);
  }
  if( sqlite3BtreeCursorHasMoved(p->pCursor) ){
    return handleMovedCursor(p);
  }
  return SQLITE_OK;
}

/*
** The following functions:
................................................................................
  u32 len;

  /* Integer and Real */
  if( serial_type<=7 && serial_type>0 ){
    u64 v;
    u32 i;
    if( serial_type==7 ){
      assert( sizeof(v)==sizeof(pMem->r) );
      memcpy(&v, &pMem->r, sizeof(v));
      swapMixedEndianFloat(v);
    }else{
      v = pMem->u.i;
    }
    len = i = sqlite3VdbeSerialTypeLen(serial_type);
    assert( i>0 );
    do{
................................................................................
    */
    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
    assert( sizeof(x)==8 && sizeof(pMem->r)==8 );
    swapMixedEndianFloat(x);
    memcpy(&pMem->r, &x, sizeof(x));
    pMem->flags = sqlite3IsNaN(pMem->r) ? MEM_Null : MEM_Real;
  }
  return 8;
}
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 */
................................................................................
  while( idx<szHdr && 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++;
    if( (++u)>=p->nField ) break;
  }
  assert( u<=pKeyInfo->nField + 1 );
  p->nField = u;
}
................................................................................
  Mem mem1;

  pKeyInfo = pPKey2->pKeyInfo;
  if( pKeyInfo->db==0 ) return 1;
  mem1.enc = pKeyInfo->enc;
  mem1.db = pKeyInfo->db;
  /* mem1.flags = 0;  // Will be initialized by sqlite3VdbeSerialGet() */
  VVA_ONLY( mem1.zMalloc = 0; ) /* Only needed by assert() statements */

  /* Compilers may complain that mem1.u.i is potentially uninitialized.
  ** We could initialize it, as shown here, to silence those complaints.
  ** But in fact, mem1.u.i will never actually be used uninitialized, and doing 
  ** the unnecessary initialization has a measurable negative performance
  ** impact, since this routine is a very high runner.  And so, we choose
  ** to ignore the compiler warnings and leave this variable uninitialized.
................................................................................
    */
    d1 += sqlite3VdbeSerialGet(&aKey1[d1], serial_type1, &mem1);

    /* Do the comparison
    */
    rc = sqlite3MemCompare(&mem1, &pPKey2->aMem[i], pKeyInfo->aColl[i]);
    if( rc!=0 ){
      assert( mem1.zMalloc==0 );  /* See comment below */
      if( pKeyInfo->aSortOrder[i] ){
        rc = -rc;  /* Invert the result for DESC sort order. */
      }
      goto debugCompareEnd;
    }
    i++;
  }while( idx1<szHdr1 && i<pPKey2->nField );

  /* 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 default_rc
  ** value.  */
  rc = pPKey2->default_rc;

debugCompareEnd:
................................................................................
    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;
    c1.db = c2.db = pMem1->db;
    c1.flags = c2.flags = 0;
    c1.zMalloc = c2.zMalloc = 0;
    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);
................................................................................
    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;
................................................................................
    if( d1>(unsigned)nKey1 ){ 
      pPKey2->errCode = (u8)SQLITE_CORRUPT_BKPT;
      return 0;  /* Corruption */
    }
    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;
................................................................................
      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( 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;
................................................................................
    }

    if( rc!=0 ){
      if( pKeyInfo->aSortOrder[i] ){
        rc = -rc;
      }
      assert( vdbeRecordCompareDebug(nKey1, pKey1, pPKey2, rc) );
      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 default_rc
  ** value.  */
  assert( CORRUPT_DB 
       || vdbeRecordCompareDebug(nKey1, pKey1, pPKey2, pPKey2->default_rc) 
       || pKeyInfo->db->mallocFailed
................................................................................
  *rowid = v.u.i;
  sqlite3VdbeMemRelease(&m);
  return SQLITE_OK;

  /* Jump here if database corruption is detected after m has been
  ** allocated.  Free the m object and return SQLITE_CORRUPT. */
idx_rowid_corruption:
  testcase( m.zMalloc!=0 );
  sqlite3VdbeMemRelease(&m);
  return SQLITE_CORRUPT_BKPT;
}

/*
** Compare the key of the index entry that cursor pC is pointing to against
** the key string in pUnpacked.  Write into *pRes a number

**
**    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 for creating, destroying, and populating
** a VDBE (or an "sqlite3_stmt" as it is known to the outside world.) 


*/
#include "sqliteInt.h"
#include "vdbeInt.h"

/*
** Create a new virtual database engine.
*/
................................................................................
        break;
      }
      case P4_MEM: {
        if( db->pnBytesFreed==0 ){
          sqlite3ValueFree((sqlite3_value*)p4);
        }else{
          Mem *p = (Mem*)p4;
          if( p->szMalloc ) sqlite3DbFree(db, p->zMalloc);
          sqlite3DbFree(db, p);
        }
        break;
      }
      case P4_VTAB : {
        if( db->pnBytesFreed==0 ) sqlite3VtabUnlock((VTable *)p4);
        break;
................................................................................
    memset(pOp, 0, sizeof(pOp[0]));
    pOp->opcode = OP_Noop;
    if( addr==p->nOp-1 ) p->nOp--;
  }
}

/*
** If the last opcode is "op" and it is not a jump destination,
** then remove it.  Return true if and only if an opcode was removed.
*/
int sqlite3VdbeDeletePriorOpcode(Vdbe *p, u8 op){
  if( (p->nOp-1)>(p->pParse->iFixedOp) && p->aOp[p->nOp-1].opcode==op ){
    sqlite3VdbeChangeToNoop(p, p->nOp-1);
    return 1;
  }else{
    return 0;
................................................................................
    case P4_MEM: {
      Mem *pMem = pOp->p4.pMem;
      if( pMem->flags & MEM_Str ){
        zP4 = pMem->z;
      }else if( pMem->flags & MEM_Int ){
        sqlite3_snprintf(nTemp, zTemp, "%lld", pMem->u.i);
      }else if( pMem->flags & MEM_Real ){
        sqlite3_snprintf(nTemp, zTemp, "%.16g", pMem->u.r);
      }else if( pMem->flags & MEM_Null ){
        sqlite3_snprintf(nTemp, zTemp, "NULL");
      }else{
        assert( pMem->flags & MEM_Blob );
        zP4 = "(blob)";
      }
      break;
................................................................................
#endif

/*
** Release an array of N Mem elements
*/
static void releaseMemArray(Mem *p, int N){
  if( p && N ){
    Mem *pEnd = &p[N];
    sqlite3 *db = p->db;
    u8 malloc_failed = db->mallocFailed;
    if( db->pnBytesFreed ){
      do{
        if( p->szMalloc ) sqlite3DbFree(db, p->zMalloc);
      }while( (++p)<pEnd );
      return;
    }
    do{
      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.
      **
................................................................................
      */
      testcase( p->flags & MEM_Agg );
      testcase( p->flags & MEM_Dyn );
      testcase( p->flags & MEM_Frame );
      testcase( p->flags & MEM_RowSet );
      if( p->flags&(MEM_Agg|MEM_Dyn|MEM_Frame|MEM_RowSet) ){
        sqlite3VdbeMemRelease(p);
      }else if( p->szMalloc ){
        sqlite3DbFree(db, p->zMalloc);
        p->szMalloc = 0;
      }

      p->flags = MEM_Undefined;
    }while( (++p)<pEnd );
    db->mallocFailed = malloc_failed;
  }
}

/*
** Delete a VdbeFrame object and its contents. VdbeFrame objects are
** allocated by the OP_Program opcode in sqlite3VdbeExec().
................................................................................
    pMem->u.i = pOp->p2;                          /* P2 */
    pMem++;

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

    if( sqlite3VdbeMemClearAndResize(pMem, 32) ){ /* 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);
................................................................................
      assert( pMem->z!=0 );
      pMem->n = sqlite3Strlen30(pMem->z);
      pMem->enc = SQLITE_UTF8;
    }
    pMem++;

    if( p->explain==1 ){
      if( sqlite3VdbeMemClearAndResize(pMem, 4) ){
        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( sqlite3VdbeMemClearAndResize(pMem, 500) ){
        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
................................................................................
  }
#endif
}

/*
** Prepare a virtual machine for execution for the first time after
** creating the virtual machine.  This involves things such
** as allocating registers and initializing the program counter.
** After the VDBE has be prepped, it can be executed by one or more
** calls to sqlite3VdbeExec().  
**
** This function may be called exactly once on each virtual machine.
** After this routine is called the VM has been "packaged" and is ready
** to run.  After this routine is called, further calls to 
** sqlite3VdbeAddOp() functions are prohibited.  This routine disconnects
................................................................................
    sqlite3BtreeClose(pCx->pBt);
    /* The pCx->pCursor will be close automatically, if it exists, by
    ** the call above. */
  }else if( pCx->pCursor ){
    sqlite3BtreeCloseCursor(pCx->pCursor);
  }
#ifndef SQLITE_OMIT_VIRTUALTABLE
  else if( pCx->pVtabCursor ){
    sqlite3_vtab_cursor *pVtabCursor = pCx->pVtabCursor;
    const sqlite3_module *pModule = pVtabCursor->pVtab->pModule;
    p->inVtabMethod = 1;
    pModule->xClose(pVtabCursor);
    p->inVtabMethod = 0;
  }
#endif
................................................................................
** open cursors.
*/
static void closeAllCursors(Vdbe *p){
  if( p->pFrame ){
    VdbeFrame *pFrame;
    for(pFrame=p->pFrame; pFrame->pParent; pFrame=pFrame->pParent);
    sqlite3VdbeFrameRestore(pFrame);

    p->pFrame = 0;
    p->nFrame = 0;
  }
  assert( p->nFrame==0 );

  if( p->apCsr ){
    int i;
    for(i=0; i<p->nCursor; i++){
      VdbeCursor *pC = p->apCsr[i];
      if( pC ){
        sqlite3VdbeFreeCursor(p, pC);
................................................................................
  while( p->pDelFrame ){
    VdbeFrame *pDel = p->pDelFrame;
    p->pDelFrame = pDel->pParent;
    sqlite3VdbeFrameDelete(pDel);
  }

  /* Delete any auxdata allocations made by the VM */
  if( p->pAuxData ) sqlite3VdbeDeleteAuxData(p, -1, 0);
  assert( p->pAuxData==0 );
}

/*
** Clean up the VM after a single run.




*/
static void Cleanup(Vdbe *p){
  sqlite3 *db = p->db;

#ifdef SQLITE_DEBUG
  /* Execute assert() statements to ensure that the Vdbe.apCsr[] and 
  ** Vdbe.aMem[] arrays have already been cleaned up.  */
................................................................................
    sqlite3DbFree(db, pSub);
  }
  for(i=p->nzVar-1; i>=0; i--) sqlite3DbFree(db, p->azVar[i]);
  vdbeFreeOpArray(db, p->aOp, p->nOp);
  sqlite3DbFree(db, p->aColName);
  sqlite3DbFree(db, p->zSql);
  sqlite3DbFree(db, p->pFree);




}

/*
** Delete an entire VDBE.
*/
void sqlite3VdbeDelete(Vdbe *p){
  sqlite3 *db;
................................................................................
#ifdef SQLITE_TEST
  extern int sqlite3_search_count;
#endif
  assert( p->deferredMoveto );
  assert( p->isTable );
  rc = sqlite3BtreeMovetoUnpacked(p->pCursor, 0, p->movetoTarget, 0, &res);
  if( rc ) return rc;

  if( res!=0 ) return SQLITE_CORRUPT_BKPT;

#ifdef SQLITE_TEST
  sqlite3_search_count++;
#endif
  p->deferredMoveto = 0;
  p->cacheStatus = CACHE_STALE;
  return SQLITE_OK;
}
................................................................................
  assert( p->pCursor!=0 );
  assert( sqlite3BtreeCursorHasMoved(p->pCursor) );
  rc = sqlite3BtreeCursorRestore(p->pCursor, &isDifferentRow);
  p->cacheStatus = CACHE_STALE;
  if( isDifferentRow ) p->nullRow = 1;
  return rc;
}

/*
** Check to ensure that the cursor is valid.  Restore the cursor
** if need be.  Return any I/O error from the restore operation.
*/
int sqlite3VdbeCursorRestore(VdbeCursor *p){
  if( sqlite3BtreeCursorHasMoved(p->pCursor) ){
    return handleMovedCursor(p);
  }
  return SQLITE_OK;
}

/*
** Make sure the cursor p is ready to read or write the row to which it
** was last positioned.  Return an error code if an OOM fault or I/O error
** prevents us from positioning the cursor to its correct position.
**
** If a MoveTo operation is pending on the given cursor, then do that
................................................................................
** If the cursor is already pointing to the correct row and that row has
** not been deleted out from under the cursor, then this routine is a no-op.
*/
int sqlite3VdbeCursorMoveto(VdbeCursor *p){
  if( p->deferredMoveto ){
    return handleDeferredMoveto(p);
  }
  if( p->pCursor && sqlite3BtreeCursorHasMoved(p->pCursor) ){
    return handleMovedCursor(p);
  }
  return SQLITE_OK;
}

/*
** The following functions:
................................................................................
  u32 len;

  /* Integer and Real */
  if( serial_type<=7 && serial_type>0 ){
    u64 v;
    u32 i;
    if( serial_type==7 ){
      assert( sizeof(v)==sizeof(pMem->u.r) );
      memcpy(&v, &pMem->u.r, sizeof(v));
      swapMixedEndianFloat(v);
    }else{
      v = pMem->u.i;
    }
    len = i = sqlite3VdbeSerialTypeLen(serial_type);
    assert( i>0 );
    do{
................................................................................
    */
    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
    assert( sizeof(x)==8 && sizeof(pMem->u.r)==8 );
    swapMixedEndianFloat(x);
    memcpy(&pMem->u.r, &x, sizeof(x));
    pMem->flags = sqlite3IsNaN(pMem->u.r) ? MEM_Null : MEM_Real;
  }
  return 8;
}
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 */
................................................................................
  while( idx<szHdr && 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->szMalloc = 0;
    d += sqlite3VdbeSerialGet(&aKey[d], serial_type, pMem);
    pMem++;
    if( (++u)>=p->nField ) break;
  }
  assert( u<=pKeyInfo->nField + 1 );
  p->nField = u;
}
................................................................................
  Mem mem1;

  pKeyInfo = pPKey2->pKeyInfo;
  if( pKeyInfo->db==0 ) return 1;
  mem1.enc = pKeyInfo->enc;
  mem1.db = pKeyInfo->db;
  /* mem1.flags = 0;  // Will be initialized by sqlite3VdbeSerialGet() */
  VVA_ONLY( mem1.szMalloc = 0; ) /* Only needed by assert() statements */

  /* Compilers may complain that mem1.u.i is potentially uninitialized.
  ** We could initialize it, as shown here, to silence those complaints.
  ** But in fact, mem1.u.i will never actually be used uninitialized, and doing 
  ** the unnecessary initialization has a measurable negative performance
  ** impact, since this routine is a very high runner.  And so, we choose
  ** to ignore the compiler warnings and leave this variable uninitialized.
................................................................................
    */
    d1 += sqlite3VdbeSerialGet(&aKey1[d1], serial_type1, &mem1);

    /* Do the comparison
    */
    rc = sqlite3MemCompare(&mem1, &pPKey2->aMem[i], pKeyInfo->aColl[i]);
    if( rc!=0 ){
      assert( mem1.szMalloc==0 );  /* See comment below */
      if( pKeyInfo->aSortOrder[i] ){
        rc = -rc;  /* Invert the result for DESC sort order. */
      }
      goto debugCompareEnd;
    }
    i++;
  }while( idx1<szHdr1 && i<pPKey2->nField );

  /* 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.szMalloc==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 default_rc
  ** value.  */
  rc = pPKey2->default_rc;

debugCompareEnd:
................................................................................
    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;
    sqlite3VdbeMemInit(&c1, pMem1->db, MEM_Null);
    sqlite3VdbeMemInit(&c2, pMem1->db, MEM_Null);

    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);
................................................................................
    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->u.r;
    }else if( (f1&MEM_Int)!=0 ){
      r1 = (double)pMem1->u.i;
    }else{
      return 1;
    }
    if( (f2&MEM_Real)!=0 ){
      r2 = pMem2->u.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;
................................................................................
    if( d1>(unsigned)nKey1 ){ 
      pPKey2->errCode = (u8)SQLITE_CORRUPT_BKPT;
      return 0;  /* Corruption */
    }
    i = 0;
  }

  VVA_ONLY( mem1.szMalloc = 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;
................................................................................
      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.u.r<rhs ){
          rc = -1;
        }else if( mem1.u.r>rhs ){
          rc = +1;
        }
      }else{
        i64 lhs = vdbeRecordDecodeInt(serial_type, &aKey1[d1]);
        i64 rhs = pRhs->u.i;
        if( lhs<rhs ){
          rc = -1;
................................................................................
    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->u.r;
        double lhs;
        sqlite3VdbeSerialGet(&aKey1[d1], serial_type, &mem1);
        if( serial_type==7 ){
          lhs = mem1.u.r;
        }else{
          lhs = (double)mem1.u.i;
        }
        if( lhs<rhs ){
          rc = -1;
        }else if( lhs>rhs ){
          rc = +1;
................................................................................
    }

    if( rc!=0 ){
      if( pKeyInfo->aSortOrder[i] ){
        rc = -rc;
      }
      assert( vdbeRecordCompareDebug(nKey1, pKey1, pPKey2, rc) );
      assert( mem1.szMalloc==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.szMalloc==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 default_rc
  ** value.  */
  assert( CORRUPT_DB 
       || vdbeRecordCompareDebug(nKey1, pKey1, pPKey2, pPKey2->default_rc) 
       || pKeyInfo->db->mallocFailed
................................................................................
  *rowid = v.u.i;
  sqlite3VdbeMemRelease(&m);
  return SQLITE_OK;

  /* Jump here if database corruption is detected after m has been
  ** allocated.  Free the m object and return SQLITE_CORRUPT. */
idx_rowid_corruption:
  testcase( m.szMalloc!=0 );
  sqlite3VdbeMemRelease(&m);
  return SQLITE_CORRUPT_BKPT;
}

/*
** Compare the key of the index entry that cursor pC is pointing to against
** the key string in pUnpacked.  Write into *pRes a number

** this:    assert( sqlite3VdbeCheckMemInvariants(pMem) );
*/
int sqlite3VdbeCheckMemInvariants(Mem *p){
  /* If MEM_Dyn is set then Mem.xDel!=0.  
  ** Mem.xDel is might not be initialized if MEM_Dyn is clear.
  */
  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 ephemeral 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;
}
................................................................................
** min(n,32) bytes.
**
** 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.
*/
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 ){
      sqlite3VdbeMemSetNull(pMem);
      pMem->z = 0;

      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);
  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
** malloc().  In this way, we know that the memory is safe to be
** overwritten or altered.























**
** Return SQLITE_OK on success or SQLITE_NOMEM if malloc fails.
*/
int sqlite3VdbeMemMakeWriteable(Mem *pMem){
  int f;
  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
  assert( (pMem->flags&MEM_RowSet)==0 );
  ExpandBlob(pMem);
  f = pMem->flags;
  if( (f&(MEM_Str|MEM_Blob)) && pMem->z!=pMem->zMalloc ){
    if( sqlite3VdbeMemGrow(pMem, pMem->n + 2, 1) ){
      return SQLITE_NOMEM;
    }
    pMem->z[pMem->n] = 0;
    pMem->z[pMem->n+1] = 0;
    pMem->flags |= MEM_Term;
#ifdef SQLITE_DEBUG
................................................................................
  assert( !(fg&MEM_Zero) );
  assert( !(fg&(MEM_Str|MEM_Blob)) );
  assert( fg&(MEM_Int|MEM_Real) );
  assert( (pMem->flags&MEM_RowSet)==0 );
  assert( EIGHT_BYTE_ALIGNMENT(pMem) );


  if( sqlite3VdbeMemGrow(pMem, nByte, 0) ){
    return SQLITE_NOMEM;
  }

  /* For a Real or Integer, use sqlite3_snprintf() to produce the UTF-8
  ** string representation of the value. Then, if the required encoding
  ** is UTF-16le or UTF-16be do a translation.
  ** 
  ** FIX ME: It would be better if sqlite3_snprintf() could do UTF-16.
  */
  if( fg & MEM_Int ){
    sqlite3_snprintf(nByte, pMem->z, "%lld", pMem->u.i);
  }else{
    assert( fg & MEM_Real );
    sqlite3_snprintf(nByte, pMem->z, "%!.15g", pMem->r);
  }
  pMem->n = sqlite3Strlen30(pMem->z);
  pMem->enc = SQLITE_UTF8;
  pMem->flags |= MEM_Str|MEM_Term;
  if( bForce ) pMem->flags &= ~(MEM_Int|MEM_Real);
  sqlite3VdbeChangeEncoding(pMem, enc);
  return SQLITE_OK;
................................................................................
    t.flags = MEM_Null;
    t.db = pMem->db;
    ctx.pOut = &t;
    ctx.pMem = pMem;
    ctx.pFunc = pFunc;
    pFunc->xFinalize(&ctx); /* IMP: R-24505-23230 */
    assert( (pMem->flags & MEM_Dyn)==0 );
    sqlite3DbFree(pMem->db, pMem->zMalloc);
    memcpy(pMem, &t, sizeof(t));
    rc = ctx.isError;
  }
  return rc;
}

/*
................................................................................
** the unusual case where there really is memory in p that needs
** to be freed.
*/
static SQLITE_NOINLINE void vdbeMemClear(Mem *p){
  if( VdbeMemDynamic(p) ){
    vdbeMemClearExternAndSetNull(p);
  }
  if( p->zMalloc ){
    sqlite3DbFree(p->db, p->zMalloc);
    p->zMalloc = 0;
  }
  p->z = 0;
}

/*
** Release any memory resources held by the Mem.  Both the memory that is
** free by Mem.xDel and the Mem.zMalloc allocation are freed.
................................................................................
** reset a Mem back to its minimum memory utilization.
**
** Use sqlite3VdbeMemSetNull() to release just the Mem.xDel space
** prior to inserting new content into the Mem.
*/
void sqlite3VdbeMemRelease(Mem *p){
  assert( sqlite3VdbeCheckMemInvariants(p) );
  if( VdbeMemDynamic(p) || p->zMalloc ){
    vdbeMemClear(p);
  }
}

/*
** Convert a 64-bit IEEE double into a 64-bit signed integer.
** If the double is out of range of a 64-bit signed integer then
................................................................................
  int flags;
  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
  assert( EIGHT_BYTE_ALIGNMENT(pMem) );
  flags = pMem->flags;
  if( flags & MEM_Int ){
    return pMem->u.i;
  }else if( flags & MEM_Real ){
    return doubleToInt64(pMem->r);
  }else if( flags & (MEM_Str|MEM_Blob) ){
    i64 value = 0;
    assert( pMem->z || pMem->n==0 );
    sqlite3Atoi64(pMem->z, &value, pMem->n, pMem->enc);
    return value;
  }else{
    return 0;
................................................................................
** value.  If it is a string or blob, try to convert it to a double.
** If it is a NULL, return 0.0.
*/
double sqlite3VdbeRealValue(Mem *pMem){
  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
  assert( EIGHT_BYTE_ALIGNMENT(pMem) );
  if( pMem->flags & MEM_Real ){
    return pMem->r;
  }else if( pMem->flags & MEM_Int ){
    return (double)pMem->u.i;
  }else if( pMem->flags & (MEM_Str|MEM_Blob) ){
    /* (double)0 In case of SQLITE_OMIT_FLOATING_POINT... */
    double val = (double)0;
    sqlite3AtoF(pMem->z, &val, pMem->n, pMem->enc);
    return val;
................................................................................
}

/*
** The MEM structure is already a MEM_Real.  Try to also make it a
** MEM_Int if we can.
*/
void sqlite3VdbeIntegerAffinity(Mem *pMem){

  assert( pMem->flags & MEM_Real );
  assert( (pMem->flags & MEM_RowSet)==0 );
  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
  assert( EIGHT_BYTE_ALIGNMENT(pMem) );

  pMem->u.i = doubleToInt64(pMem->r);

  /* Only mark the value as an integer if
  **
  **    (1) the round-trip conversion real->int->real is a no-op, and
  **    (2) The integer is neither the largest nor the smallest
  **        possible integer (ticket #3922)
  **
  ** The second and third terms in the following conditional enforces
  ** the second condition under the assumption that addition overflow causes
  ** values to wrap around.
  */
  if( pMem->r==(double)pMem->u.i
   && pMem->u.i>SMALLEST_INT64
   && pMem->u.i<LARGEST_INT64
  ){
    pMem->flags |= MEM_Int;
  }
}

/*
** Convert pMem to type integer.  Invalidate any prior representations.
*/
int sqlite3VdbeMemIntegerify(Mem *pMem){
................................................................................
** Convert pMem so that it is of type MEM_Real.
** Invalidate any prior representations.
*/
int sqlite3VdbeMemRealify(Mem *pMem){
  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
  assert( EIGHT_BYTE_ALIGNMENT(pMem) );

  pMem->r = sqlite3VdbeRealValue(pMem);
  MemSetTypeFlag(pMem, MEM_Real);
  return SQLITE_OK;
}

/*
** Convert pMem so that it has types MEM_Real or MEM_Int or both.
** Invalidate any prior representations.
................................................................................
int sqlite3VdbeMemNumerify(Mem *pMem){
  if( (pMem->flags & (MEM_Int|MEM_Real|MEM_Null))==0 ){
    assert( (pMem->flags & (MEM_Blob|MEM_Str))!=0 );
    assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
    if( 0==sqlite3Atoi64(pMem->z, &pMem->u.i, pMem->n, pMem->enc) ){
      MemSetTypeFlag(pMem, MEM_Int);
    }else{
      pMem->r = sqlite3VdbeRealValue(pMem);
      MemSetTypeFlag(pMem, MEM_Real);
      sqlite3VdbeIntegerAffinity(pMem);
    }
  }
  assert( (pMem->flags & (MEM_Int|MEM_Real|MEM_Null))!=0 );
  pMem->flags &= ~(MEM_Str|MEM_Blob);
  return SQLITE_OK;
................................................................................
**
** The minimum amount of initialization feasible is performed.
*/
void sqlite3VdbeMemInit(Mem *pMem, sqlite3 *db, u16 flags){
  assert( (flags & ~MEM_TypeMask)==0 );
  pMem->flags = flags;
  pMem->db = db;
  pMem->zMalloc = 0;
}


/*
** Delete any previous value and set the value stored in *pMem to NULL.
**
** This routine calls the Mem.xDel destructor to dispose of values that
................................................................................
/*
** Delete any previous value and set the value stored in *pMem to val,
** manifest type REAL.
*/
void sqlite3VdbeMemSetDouble(Mem *pMem, double val){
  sqlite3VdbeMemSetNull(pMem);
  if( !sqlite3IsNaN(val) ){
    pMem->r = val;
    pMem->flags = MEM_Real;
  }
}
#endif

/*
** Delete any previous value and set the value of pMem to be an
................................................................................
  sqlite3 *db = pMem->db;
  assert( db!=0 );
  assert( (pMem->flags & MEM_RowSet)==0 );
  sqlite3VdbeMemRelease(pMem);
  pMem->zMalloc = sqlite3DbMallocRaw(db, 64);
  if( db->mallocFailed ){
    pMem->flags = MEM_Null;

  }else{
    assert( pMem->zMalloc );

    pMem->u.pRowSet = sqlite3RowSetInit(db, pMem->zMalloc, 
                                       sqlite3DbMallocSize(db, pMem->zMalloc));
    assert( pMem->u.pRowSet!=0 );
    pMem->flags = MEM_RowSet;
  }
}

/*
** Return true if the Mem object contains a TEXT or BLOB that is
................................................................................
  assert( pFrom->db==0 || sqlite3_mutex_held(pFrom->db->mutex) );
  assert( pTo->db==0 || sqlite3_mutex_held(pTo->db->mutex) );
  assert( pFrom->db==0 || pTo->db==0 || pFrom->db==pTo->db );

  sqlite3VdbeMemRelease(pTo);
  memcpy(pTo, pFrom, sizeof(Mem));
  pFrom->flags = MEM_Null;
  pFrom->zMalloc = 0;
}

/*
** Change the value of a Mem to be a string or a BLOB.
**
** The memory management strategy depends on the value of the xDel
** parameter. If the value passed is SQLITE_TRANSIENT, then the 
................................................................................
    int nAlloc = nByte;
    if( flags&MEM_Term ){
      nAlloc += (enc==SQLITE_UTF8?1:2);
    }
    if( nByte>iLimit ){
      return SQLITE_TOOBIG;
    }



    if( sqlite3VdbeMemGrow(pMem, nAlloc, 0) ){
      return SQLITE_NOMEM;
    }
    memcpy(pMem->z, z, nAlloc);
  }else if( xDel==SQLITE_DYNAMIC ){
    sqlite3VdbeMemRelease(pMem);
    pMem->zMalloc = pMem->z = (char *)z;

  }else{
    sqlite3VdbeMemRelease(pMem);
    pMem->z = (char *)z;
    pMem->xDel = xDel;
    flags |= ((xDel==SQLITE_STATIC)?MEM_Static:MEM_Dyn);
  }

................................................................................

  if( offset+amt<=available ){
    pMem->z = &zData[offset];
    pMem->flags = MEM_Blob|MEM_Ephem;
    pMem->n = (int)amt;
  }else{
    pMem->flags = MEM_Null;
    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;
................................................................................
}

/*
** The pVal argument is known to be a value other than NULL.
** Convert it into a string with encoding enc and return a pointer
** to a zero-terminated version of that string.
*/
SQLITE_NOINLINE const void *valueToText(sqlite3_value* pVal, u8 enc){
  assert( pVal!=0 );
  assert( pVal->db==0 || sqlite3_mutex_held(pVal->db->mutex) );
  assert( (enc&3)==(enc&~SQLITE_UTF16_ALIGNED) );
  assert( (pVal->flags & MEM_RowSet)==0 );
  assert( (pVal->flags & (MEM_Null))==0 );
  if( pVal->flags & (MEM_Blob|MEM_Str) ){
    pVal->flags |= MEM_Str;
................................................................................
    }
  }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 ){
    pVal = valueNew(db, pCtx);
    if( pVal==0 ) goto no_mem;
  }
#ifndef SQLITE_OMIT_BLOB_LITERAL
................................................................................
void sqlite3Stat4ProbeFree(UnpackedRecord *pRec){
  if( pRec ){
    int i;
    int nCol = pRec->pKeyInfo->nField+pRec->pKeyInfo->nXField;
    Mem *aMem = pRec->aMem;
    sqlite3 *db = aMem[0].db;
    for(i=0; i<nCol; i++){
      sqlite3DbFree(db, aMem[i].zMalloc);
    }
    sqlite3KeyInfoUnref(pRec->pKeyInfo);
    sqlite3DbFree(db, pRec);
  }
}
#endif /* ifdef SQLITE_ENABLE_STAT4 */

** this:    assert( sqlite3VdbeCheckMemInvariants(pMem) );
*/
int sqlite3VdbeCheckMemInvariants(Mem *p){
  /* If MEM_Dyn is set then Mem.xDel!=0.  
  ** Mem.xDel is might not be initialized if MEM_Dyn is clear.
  */
  assert( (p->flags & MEM_Dyn)==0 || p->xDel!=0 );

  /* MEM_Dyn may only be set if Mem.szMalloc==0.  In this way we
  ** ensure that if Mem.szMalloc>0 then it is safe to do
  ** Mem.z = Mem.zMalloc without having to check Mem.flags&MEM_Dyn.
  ** That saves a few cycles in inner loops. */
  assert( (p->flags & MEM_Dyn)==0 || p->szMalloc==0 );

  /* Cannot be both MEM_Int and MEM_Real at the same time */
  assert( (p->flags & (MEM_Int|MEM_Real))!=(MEM_Int|MEM_Real) );

  /* The szMalloc field holds the correct memory allocation size */
  assert( p->szMalloc==0
       || p->szMalloc==sqlite3DbMallocSize(p->db,p->zMalloc) );

  /* 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 ephemeral string or blob
  **   (4) A static string or blob
  */
  if( (p->flags & (MEM_Str|MEM_Blob)) && p->n>0 ){
    assert( 
      ((p->szMalloc>0 && 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;
}
................................................................................
** min(n,32) bytes.
**
** 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_NOINLINE 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 );

  assert( pMem->szMalloc==0
       || pMem->szMalloc==sqlite3DbMallocSize(pMem->db, pMem->zMalloc) );
  if( pMem->szMalloc<n ){
    if( n<32 ) n = 32;
    if( bPreserve && pMem->szMalloc>0 && pMem->z==pMem->zMalloc ){
      pMem->z = pMem->zMalloc = sqlite3DbReallocOrFree(pMem->db, pMem->z, n);
      bPreserve = 0;
    }else{
      if( pMem->szMalloc>0 ) sqlite3DbFree(pMem->db, pMem->zMalloc);
      pMem->zMalloc = sqlite3DbMallocRaw(pMem->db, n);
    }
    if( pMem->zMalloc==0 ){
      sqlite3VdbeMemSetNull(pMem);
      pMem->z = 0;
      pMem->szMalloc = 0;
      return SQLITE_NOMEM;
    }else{
      pMem->szMalloc = sqlite3DbMallocSize(pMem->db, pMem->zMalloc);
    }
  }

  if( bPreserve && pMem->z && 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);
  return SQLITE_OK;
}

/*
** Change the pMem->zMalloc allocation to be at least szNew bytes.
** If pMem->zMalloc already meets or exceeds the requested size, this
** routine is a no-op.
**
** Any prior string or blob content in the pMem object may be discarded.
** The pMem->xDel destructor is called, if it exists.  Though MEM_Str
** and MEM_Blob values may be discarded, MEM_Int, MEM_Real, and MEM_Null
** values are preserved.
**
** Return SQLITE_OK on success or an error code (probably SQLITE_NOMEM)
** if unable to complete the resizing.
*/
int sqlite3VdbeMemClearAndResize(Mem *pMem, int szNew){
  assert( szNew>0 );
  assert( (pMem->flags & MEM_Dyn)==0 || pMem->szMalloc==0 );
  if( pMem->szMalloc<szNew ){
    return sqlite3VdbeMemGrow(pMem, szNew, 0);
  }
  assert( (pMem->flags & MEM_Dyn)==0 );
  pMem->z = pMem->zMalloc;
  pMem->flags &= (MEM_Null|MEM_Int|MEM_Real);
  return SQLITE_OK;
}

/*
** Change pMem so that its MEM_Str or MEM_Blob value is stored in
** MEM.zMalloc, where it can be safely written.
**
** Return SQLITE_OK on success or SQLITE_NOMEM if malloc fails.
*/
int sqlite3VdbeMemMakeWriteable(Mem *pMem){
  int f;
  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
  assert( (pMem->flags&MEM_RowSet)==0 );
  ExpandBlob(pMem);
  f = pMem->flags;
  if( (f&(MEM_Str|MEM_Blob)) && (pMem->szMalloc==0 || pMem->z!=pMem->zMalloc) ){
    if( sqlite3VdbeMemGrow(pMem, pMem->n + 2, 1) ){
      return SQLITE_NOMEM;
    }
    pMem->z[pMem->n] = 0;
    pMem->z[pMem->n+1] = 0;
    pMem->flags |= MEM_Term;
#ifdef SQLITE_DEBUG
................................................................................
  assert( !(fg&MEM_Zero) );
  assert( !(fg&(MEM_Str|MEM_Blob)) );
  assert( fg&(MEM_Int|MEM_Real) );
  assert( (pMem->flags&MEM_RowSet)==0 );
  assert( EIGHT_BYTE_ALIGNMENT(pMem) );


  if( sqlite3VdbeMemClearAndResize(pMem, nByte) ){
    return SQLITE_NOMEM;
  }

  /* For a Real or Integer, use sqlite3_snprintf() to produce the UTF-8
  ** string representation of the value. Then, if the required encoding
  ** is UTF-16le or UTF-16be do a translation.
  ** 
  ** FIX ME: It would be better if sqlite3_snprintf() could do UTF-16.
  */
  if( fg & MEM_Int ){
    sqlite3_snprintf(nByte, pMem->z, "%lld", pMem->u.i);
  }else{
    assert( fg & MEM_Real );
    sqlite3_snprintf(nByte, pMem->z, "%!.15g", pMem->u.r);
  }
  pMem->n = sqlite3Strlen30(pMem->z);
  pMem->enc = SQLITE_UTF8;
  pMem->flags |= MEM_Str|MEM_Term;
  if( bForce ) pMem->flags &= ~(MEM_Int|MEM_Real);
  sqlite3VdbeChangeEncoding(pMem, enc);
  return SQLITE_OK;
................................................................................
    t.flags = MEM_Null;
    t.db = pMem->db;
    ctx.pOut = &t;
    ctx.pMem = pMem;
    ctx.pFunc = pFunc;
    pFunc->xFinalize(&ctx); /* IMP: R-24505-23230 */
    assert( (pMem->flags & MEM_Dyn)==0 );
    if( pMem->szMalloc>0 ) sqlite3DbFree(pMem->db, pMem->zMalloc);
    memcpy(pMem, &t, sizeof(t));
    rc = ctx.isError;
  }
  return rc;
}

/*
................................................................................
** the unusual case where there really is memory in p that needs
** to be freed.
*/
static SQLITE_NOINLINE void vdbeMemClear(Mem *p){
  if( VdbeMemDynamic(p) ){
    vdbeMemClearExternAndSetNull(p);
  }
  if( p->szMalloc ){
    sqlite3DbFree(p->db, p->zMalloc);
    p->szMalloc = 0;
  }
  p->z = 0;
}

/*
** Release any memory resources held by the Mem.  Both the memory that is
** free by Mem.xDel and the Mem.zMalloc allocation are freed.
................................................................................
** reset a Mem back to its minimum memory utilization.
**
** Use sqlite3VdbeMemSetNull() to release just the Mem.xDel space
** prior to inserting new content into the Mem.
*/
void sqlite3VdbeMemRelease(Mem *p){
  assert( sqlite3VdbeCheckMemInvariants(p) );
  if( VdbeMemDynamic(p) || p->szMalloc ){
    vdbeMemClear(p);
  }
}

/*
** Convert a 64-bit IEEE double into a 64-bit signed integer.
** If the double is out of range of a 64-bit signed integer then
................................................................................
  int flags;
  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
  assert( EIGHT_BYTE_ALIGNMENT(pMem) );
  flags = pMem->flags;
  if( flags & MEM_Int ){
    return pMem->u.i;
  }else if( flags & MEM_Real ){
    return doubleToInt64(pMem->u.r);
  }else if( flags & (MEM_Str|MEM_Blob) ){
    i64 value = 0;
    assert( pMem->z || pMem->n==0 );
    sqlite3Atoi64(pMem->z, &value, pMem->n, pMem->enc);
    return value;
  }else{
    return 0;
................................................................................
** value.  If it is a string or blob, try to convert it to a double.
** If it is a NULL, return 0.0.
*/
double sqlite3VdbeRealValue(Mem *pMem){
  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
  assert( EIGHT_BYTE_ALIGNMENT(pMem) );
  if( pMem->flags & MEM_Real ){
    return pMem->u.r;
  }else if( pMem->flags & MEM_Int ){
    return (double)pMem->u.i;
  }else if( pMem->flags & (MEM_Str|MEM_Blob) ){
    /* (double)0 In case of SQLITE_OMIT_FLOATING_POINT... */
    double val = (double)0;
    sqlite3AtoF(pMem->z, &val, pMem->n, pMem->enc);
    return val;
................................................................................
}

/*
** The MEM structure is already a MEM_Real.  Try to also make it a
** MEM_Int if we can.
*/
void sqlite3VdbeIntegerAffinity(Mem *pMem){
  i64 ix;
  assert( pMem->flags & MEM_Real );
  assert( (pMem->flags & MEM_RowSet)==0 );
  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
  assert( EIGHT_BYTE_ALIGNMENT(pMem) );

  ix = doubleToInt64(pMem->u.r);

  /* Only mark the value as an integer if
  **
  **    (1) the round-trip conversion real->int->real is a no-op, and
  **    (2) The integer is neither the largest nor the smallest
  **        possible integer (ticket #3922)
  **
  ** The second and third terms in the following conditional enforces
  ** the second condition under the assumption that addition overflow causes
  ** values to wrap around.
  */
  if( pMem->u.r==ix && ix>SMALLEST_INT64 && ix<LARGEST_INT64 ){
    pMem->u.i = ix;
    MemSetTypeFlag(pMem, MEM_Int);


  }
}

/*
** Convert pMem to type integer.  Invalidate any prior representations.
*/
int sqlite3VdbeMemIntegerify(Mem *pMem){
................................................................................
** Convert pMem so that it is of type MEM_Real.
** Invalidate any prior representations.
*/
int sqlite3VdbeMemRealify(Mem *pMem){
  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
  assert( EIGHT_BYTE_ALIGNMENT(pMem) );

  pMem->u.r = sqlite3VdbeRealValue(pMem);
  MemSetTypeFlag(pMem, MEM_Real);
  return SQLITE_OK;
}

/*
** Convert pMem so that it has types MEM_Real or MEM_Int or both.
** Invalidate any prior representations.
................................................................................
int sqlite3VdbeMemNumerify(Mem *pMem){
  if( (pMem->flags & (MEM_Int|MEM_Real|MEM_Null))==0 ){
    assert( (pMem->flags & (MEM_Blob|MEM_Str))!=0 );
    assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
    if( 0==sqlite3Atoi64(pMem->z, &pMem->u.i, pMem->n, pMem->enc) ){
      MemSetTypeFlag(pMem, MEM_Int);
    }else{
      pMem->u.r = sqlite3VdbeRealValue(pMem);
      MemSetTypeFlag(pMem, MEM_Real);
      sqlite3VdbeIntegerAffinity(pMem);
    }
  }
  assert( (pMem->flags & (MEM_Int|MEM_Real|MEM_Null))!=0 );
  pMem->flags &= ~(MEM_Str|MEM_Blob);
  return SQLITE_OK;
................................................................................
**
** The minimum amount of initialization feasible is performed.
*/
void sqlite3VdbeMemInit(Mem *pMem, sqlite3 *db, u16 flags){
  assert( (flags & ~MEM_TypeMask)==0 );
  pMem->flags = flags;
  pMem->db = db;
  pMem->szMalloc = 0;
}


/*
** Delete any previous value and set the value stored in *pMem to NULL.
**
** This routine calls the Mem.xDel destructor to dispose of values that
................................................................................
/*
** Delete any previous value and set the value stored in *pMem to val,
** manifest type REAL.
*/
void sqlite3VdbeMemSetDouble(Mem *pMem, double val){
  sqlite3VdbeMemSetNull(pMem);
  if( !sqlite3IsNaN(val) ){
    pMem->u.r = val;
    pMem->flags = MEM_Real;
  }
}
#endif

/*
** Delete any previous value and set the value of pMem to be an
................................................................................
  sqlite3 *db = pMem->db;
  assert( db!=0 );
  assert( (pMem->flags & MEM_RowSet)==0 );
  sqlite3VdbeMemRelease(pMem);
  pMem->zMalloc = sqlite3DbMallocRaw(db, 64);
  if( db->mallocFailed ){
    pMem->flags = MEM_Null;
    pMem->szMalloc = 0;
  }else{
    assert( pMem->zMalloc );
    pMem->szMalloc = sqlite3DbMallocSize(db, pMem->zMalloc);
    pMem->u.pRowSet = sqlite3RowSetInit(db, pMem->zMalloc, pMem->szMalloc);

    assert( pMem->u.pRowSet!=0 );
    pMem->flags = MEM_RowSet;
  }
}

/*
** Return true if the Mem object contains a TEXT or BLOB that is
................................................................................
  assert( pFrom->db==0 || sqlite3_mutex_held(pFrom->db->mutex) );
  assert( pTo->db==0 || sqlite3_mutex_held(pTo->db->mutex) );
  assert( pFrom->db==0 || pTo->db==0 || pFrom->db==pTo->db );

  sqlite3VdbeMemRelease(pTo);
  memcpy(pTo, pFrom, sizeof(Mem));
  pFrom->flags = MEM_Null;
  pFrom->szMalloc = 0;
}

/*
** Change the value of a Mem to be a string or a BLOB.
**
** The memory management strategy depends on the value of the xDel
** parameter. If the value passed is SQLITE_TRANSIENT, then the 
................................................................................
    int nAlloc = nByte;
    if( flags&MEM_Term ){
      nAlloc += (enc==SQLITE_UTF8?1:2);
    }
    if( nByte>iLimit ){
      return SQLITE_TOOBIG;
    }
    testcase( nAlloc==0 );
    testcase( nAlloc==31 );
    testcase( nAlloc==32 );
    if( sqlite3VdbeMemClearAndResize(pMem, MAX(nAlloc,32)) ){
      return SQLITE_NOMEM;
    }
    memcpy(pMem->z, z, nAlloc);
  }else if( xDel==SQLITE_DYNAMIC ){
    sqlite3VdbeMemRelease(pMem);
    pMem->zMalloc = pMem->z = (char *)z;
    pMem->szMalloc = sqlite3DbMallocSize(pMem->db, pMem->zMalloc);
  }else{
    sqlite3VdbeMemRelease(pMem);
    pMem->z = (char *)z;
    pMem->xDel = xDel;
    flags |= ((xDel==SQLITE_STATIC)?MEM_Static:MEM_Dyn);
  }

................................................................................

  if( offset+amt<=available ){
    pMem->z = &zData[offset];
    pMem->flags = MEM_Blob|MEM_Ephem;
    pMem->n = (int)amt;
  }else{
    pMem->flags = MEM_Null;
    if( SQLITE_OK==(rc = sqlite3VdbeMemClearAndResize(pMem, amt+2)) ){
      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;
................................................................................
}

/*
** The pVal argument is known to be a value other than NULL.
** Convert it into a string with encoding enc and return a pointer
** to a zero-terminated version of that string.
*/
static SQLITE_NOINLINE const void *valueToText(sqlite3_value* pVal, u8 enc){
  assert( pVal!=0 );
  assert( pVal->db==0 || sqlite3_mutex_held(pVal->db->mutex) );
  assert( (enc&3)==(enc&~SQLITE_UTF16_ALIGNED) );
  assert( (pVal->flags & MEM_RowSet)==0 );
  assert( (pVal->flags & (MEM_Null))==0 );
  if( pVal->flags & (MEM_Blob|MEM_Str) ){
    pVal->flags |= MEM_Str;
................................................................................
    }
  }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->flags & MEM_Real ){
        pVal->u.r = -pVal->u.r;
      }else if( pVal->u.i==SMALLEST_INT64 ){
        pVal->u.r = -(double)SMALLEST_INT64;
        MemSetTypeFlag(pVal, MEM_Real);
      }else{
        pVal->u.i = -pVal->u.i;
      }

      sqlite3ValueApplyAffinity(pVal, affinity, enc);
    }
  }else if( op==TK_NULL ){
    pVal = valueNew(db, pCtx);
    if( pVal==0 ) goto no_mem;
  }
#ifndef SQLITE_OMIT_BLOB_LITERAL
................................................................................
void sqlite3Stat4ProbeFree(UnpackedRecord *pRec){
  if( pRec ){
    int i;
    int nCol = pRec->pKeyInfo->nField+pRec->pKeyInfo->nXField;
    Mem *aMem = pRec->aMem;
    sqlite3 *db = aMem[0].db;
    for(i=0; i<nCol; i++){
      if( aMem[i].szMalloc ) sqlite3DbFree(db, aMem[i].zMalloc);
    }
    sqlite3KeyInfoUnref(pRec->pKeyInfo);
    sqlite3DbFree(db, pRec);
  }
}
#endif /* ifdef SQLITE_ENABLE_STAT4 */

** attempts to extend the file to nByte bytes in size and to ensure that
** the VFS has memory mapped it.
**
** Whether or not the file does end up memory mapped of course depends on
** the specific VFS implementation.
*/
static void vdbeSorterExtendFile(sqlite3 *db, sqlite3_file *pFd, i64 nByte){
  if( nByte<=(i64)(db->nMaxSorterMmap) ){
    int rc = sqlite3OsTruncate(pFd, nByte);
    if( rc==SQLITE_OK && pFd->pMethods->iVersion>=3 ){
      void *p = 0;
      sqlite3OsFetch(pFd, 0, (int)nByte, &p);
      sqlite3OsUnfetch(pFd, 0, p);
    }
  }
}
#else
................................................................................

  rc = vdbeSorterMergeTreeBuild(pSorter, &pMain);
  if( rc==SQLITE_OK ){
#if SQLITE_MAX_WORKER_THREADS
    assert( pSorter->bUseThreads==0 || pSorter->nTask>1 );
    if( pSorter->bUseThreads ){
      int iTask;
      PmaReader *pReadr;
      SortSubtask *pLast = &pSorter->aTask[pSorter->nTask-1];
      rc = vdbeSortAllocUnpacked(pLast);
      if( rc==SQLITE_OK ){
        pReadr = (PmaReader*)sqlite3DbMallocZero(db, sizeof(PmaReader));
        pSorter->pReader = pReadr;
        if( pReadr==0 ) rc = SQLITE_NOMEM;
      }
................................................................................
** Copy the current sorter key into the memory cell pOut.
*/
int sqlite3VdbeSorterRowkey(const VdbeCursor *pCsr, Mem *pOut){
  VdbeSorter *pSorter = pCsr->pSorter;
  void *pKey; int nKey;           /* Sorter key to copy into pOut */

  pKey = vdbeSorterRowkey(pSorter, &nKey);
  if( sqlite3VdbeMemGrow(pOut, nKey, 0) ){
    return SQLITE_NOMEM;
  }
  pOut->n = nKey;
  MemSetTypeFlag(pOut, MEM_Blob);
  memcpy(pOut->z, pKey, nKey);

  return SQLITE_OK;

** attempts to extend the file to nByte bytes in size and to ensure that
** the VFS has memory mapped it.
**
** Whether or not the file does end up memory mapped of course depends on
** the specific VFS implementation.
*/
static void vdbeSorterExtendFile(sqlite3 *db, sqlite3_file *pFd, i64 nByte){
  if( nByte<=(i64)(db->nMaxSorterMmap) && pFd->pMethods->iVersion>=3 ){
    int rc = sqlite3OsTruncate(pFd, nByte);
    if( rc==SQLITE_OK ){
      void *p = 0;
      sqlite3OsFetch(pFd, 0, (int)nByte, &p);
      sqlite3OsUnfetch(pFd, 0, p);
    }
  }
}
#else
................................................................................

  rc = vdbeSorterMergeTreeBuild(pSorter, &pMain);
  if( rc==SQLITE_OK ){
#if SQLITE_MAX_WORKER_THREADS
    assert( pSorter->bUseThreads==0 || pSorter->nTask>1 );
    if( pSorter->bUseThreads ){
      int iTask;
      PmaReader *pReadr = 0;
      SortSubtask *pLast = &pSorter->aTask[pSorter->nTask-1];
      rc = vdbeSortAllocUnpacked(pLast);
      if( rc==SQLITE_OK ){
        pReadr = (PmaReader*)sqlite3DbMallocZero(db, sizeof(PmaReader));
        pSorter->pReader = pReadr;
        if( pReadr==0 ) rc = SQLITE_NOMEM;
      }
................................................................................
** Copy the current sorter key into the memory cell pOut.
*/
int sqlite3VdbeSorterRowkey(const VdbeCursor *pCsr, Mem *pOut){
  VdbeSorter *pSorter = pCsr->pSorter;
  void *pKey; int nKey;           /* Sorter key to copy into pOut */

  pKey = vdbeSorterRowkey(pSorter, &nKey);
  if( sqlite3VdbeMemClearAndResize(pOut, nKey) ){
    return SQLITE_NOMEM;
  }
  pOut->n = nKey;
  MemSetTypeFlag(pOut, MEM_Blob);
  memcpy(pOut->z, pKey, nKey);

  return SQLITE_OK;

      assert( idx>0 && idx<=p->nVar );
      pVar = &p->aVar[idx-1];
      if( pVar->flags & MEM_Null ){
        sqlite3StrAccumAppend(&out, "NULL", 4);
      }else if( pVar->flags & MEM_Int ){
        sqlite3XPrintf(&out, 0, "%lld", pVar->u.i);
      }else if( pVar->flags & MEM_Real ){
        sqlite3XPrintf(&out, 0, "%!.15g", pVar->r);
      }else if( pVar->flags & MEM_Str ){
        int nOut;  /* Number of bytes of the string text to include in output */
#ifndef SQLITE_OMIT_UTF16
        u8 enc = ENC(db);
        Mem utf8;
        if( enc!=SQLITE_UTF8 ){
          memset(&utf8, 0, sizeof(utf8));
................................................................................
      }
    }
  }
  return sqlite3StrAccumFinish(&out);
}

#endif /* #ifndef SQLITE_OMIT_TRACE */

/*****************************************************************************
** The following code implements the data-structure explaining logic
** for the Vdbe.
*/

#if defined(SQLITE_ENABLE_TREE_EXPLAIN)

/*
** Allocate a new Explain object
*/
void sqlite3ExplainBegin(Vdbe *pVdbe){
  if( pVdbe ){
    Explain *p;
    sqlite3BeginBenignMalloc();
    p = (Explain *)sqlite3MallocZero( sizeof(Explain) );
    if( p ){
      p->pVdbe = pVdbe;
      sqlite3_free(pVdbe->pExplain);
      pVdbe->pExplain = p;
      sqlite3StrAccumInit(&p->str, p->zBase, sizeof(p->zBase),
                          SQLITE_MAX_LENGTH);
      p->str.useMalloc = 2;
    }else{
      sqlite3EndBenignMalloc();
    }
  }
}

/*
** Return true if the Explain ends with a new-line.
*/
static int endsWithNL(Explain *p){
  return p && p->str.zText && p->str.nChar
           && p->str.zText[p->str.nChar-1]=='\n';
}
    
/*
** Append text to the indentation
*/
void sqlite3ExplainPrintf(Vdbe *pVdbe, const char *zFormat, ...){
  Explain *p;
  if( pVdbe && (p = pVdbe->pExplain)!=0 ){
    va_list ap;
    if( p->nIndent && endsWithNL(p) ){
      int n = p->nIndent;
      if( n>ArraySize(p->aIndent) ) n = ArraySize(p->aIndent);
      sqlite3AppendSpace(&p->str, p->aIndent[n-1]);
    }   
    va_start(ap, zFormat);
    sqlite3VXPrintf(&p->str, SQLITE_PRINTF_INTERNAL, zFormat, ap);
    va_end(ap);
  }
}

/*
** Append a '\n' if there is not already one.
*/
void sqlite3ExplainNL(Vdbe *pVdbe){
  Explain *p;
  if( pVdbe && (p = pVdbe->pExplain)!=0 && !endsWithNL(p) ){
    sqlite3StrAccumAppend(&p->str, "\n", 1);
  }
}

/*
** Push a new indentation level.  Subsequent lines will be indented
** so that they begin at the current cursor position.
*/
void sqlite3ExplainPush(Vdbe *pVdbe){
  Explain *p;
  if( pVdbe && (p = pVdbe->pExplain)!=0 ){
    if( p->str.zText && p->nIndent<ArraySize(p->aIndent) ){
      const char *z = p->str.zText;
      int i = p->str.nChar-1;
      int x;
      while( i>=0 && z[i]!='\n' ){ i--; }
      x = (p->str.nChar - 1) - i;
      if( p->nIndent && x<p->aIndent[p->nIndent-1] ){
        x = p->aIndent[p->nIndent-1];
      }
      p->aIndent[p->nIndent] = x;
    }
    p->nIndent++;
  }
}

/*
** Pop the indentation stack by one level.
*/
void sqlite3ExplainPop(Vdbe *p){
  if( p && p->pExplain ) p->pExplain->nIndent--;
}

/*
** Free the indentation structure
*/
void sqlite3ExplainFinish(Vdbe *pVdbe){
  if( pVdbe && pVdbe->pExplain ){
    sqlite3_free(pVdbe->zExplain);
    sqlite3ExplainNL(pVdbe);
    pVdbe->zExplain = sqlite3StrAccumFinish(&pVdbe->pExplain->str);
    sqlite3_free(pVdbe->pExplain);
    pVdbe->pExplain = 0;
    sqlite3EndBenignMalloc();
  }
}

/*
** Return the explanation of a virtual machine.
*/
const char *sqlite3VdbeExplanation(Vdbe *pVdbe){
  return (pVdbe && pVdbe->zExplain) ? pVdbe->zExplain : 0;
}
#endif /* defined(SQLITE_DEBUG) */

      assert( idx>0 && idx<=p->nVar );
      pVar = &p->aVar[idx-1];
      if( pVar->flags & MEM_Null ){
        sqlite3StrAccumAppend(&out, "NULL", 4);
      }else if( pVar->flags & MEM_Int ){
        sqlite3XPrintf(&out, 0, "%lld", pVar->u.i);
      }else if( pVar->flags & MEM_Real ){
        sqlite3XPrintf(&out, 0, "%!.15g", pVar->u.r);
      }else if( pVar->flags & MEM_Str ){
        int nOut;  /* Number of bytes of the string text to include in output */
#ifndef SQLITE_OMIT_UTF16
        u8 enc = ENC(db);
        Mem utf8;
        if( enc!=SQLITE_UTF8 ){
          memset(&utf8, 0, sizeof(utf8));
................................................................................
      }
    }
  }
  return sqlite3StrAccumFinish(&out);
}

#endif /* #ifndef SQLITE_OMIT_TRACE */

      *pzErr = sqlite3MPrintf(db, "%s", zErr);
      sqlite3_free(zErr);
    }
    sqlite3DbFree(db, pVTable);
  }else if( ALWAYS(pVTable->pVtab) ){
    /* Justification of ALWAYS():  A correct vtab constructor must allocate
    ** the sqlite3_vtab object if successful.  */

    pVTable->pVtab->pModule = pMod->pModule;
    pVTable->nRef = 1;
    if( sCtx.pTab ){
      const char *zFormat = "vtable constructor did not declare schema: %s";
      *pzErr = sqlite3MPrintf(db, zFormat, pTab->zName);
      sqlite3VtabUnlock(pVTable);
      rc = SQLITE_ERROR;

      *pzErr = sqlite3MPrintf(db, "%s", zErr);
      sqlite3_free(zErr);
    }
    sqlite3DbFree(db, pVTable);
  }else if( ALWAYS(pVTable->pVtab) ){
    /* Justification of ALWAYS():  A correct vtab constructor must allocate
    ** the sqlite3_vtab object if successful.  */
    memset(pVTable->pVtab, 0, sizeof(pVTable->pVtab[0]));
    pVTable->pVtab->pModule = pMod->pModule;
    pVTable->nRef = 1;
    if( sCtx.pTab ){
      const char *zFormat = "vtable constructor did not declare schema: %s";
      *pzErr = sqlite3MPrintf(db, zFormat, pTab->zName);
      sqlite3VtabUnlock(pVTable);
      rc = SQLITE_ERROR;

  assert( TK_GT>TK_EQ && TK_GT<TK_GE );
  assert( TK_LT>TK_EQ && TK_LT<TK_GE );
  assert( TK_LE>TK_EQ && TK_LE<TK_GE );
  assert( TK_GE==TK_EQ+4 );
  return op==TK_IN || (op>=TK_EQ && op<=TK_GE) || op==TK_ISNULL;
}

/*
** Swap two objects of type TYPE.
*/
#define SWAP(TYPE,A,B) {TYPE t=A; A=B; B=t;}

/*
** Commute a comparison operator.  Expressions of the form "X op Y"
** are converted into "Y op X".
**
** If left/right precedence rules come into play when determining the
** collating sequence, then COLLATE operators are adjusted to ensure
** that the collating sequence does not change.  For example:
................................................................................
      }else{
        /* Note: this call could be optimized away - since the same values must 
        ** have been requested when testing key $P in whereEqualScanEst().  */
        whereKeyStats(pParse, p, pRec, 0, a);
        iLower = a[0];
        iUpper = a[0] + a[1];
      }









      /* If possible, improve on the iLower estimate using ($P:$L). */
      if( pLower ){
        int bOk;                    /* True if value is extracted from pExpr */
        Expr *pExpr = pLower->pExpr->pRight;
        assert( (pLower->eOperator & (WO_GT|WO_GE))!=0 );
        rc = sqlite3Stat4ProbeSetValue(pParse, p, &pRec, pExpr, aff, nEq, &bOk);
        if( rc==SQLITE_OK && bOk ){
          tRowcnt iNew;
          whereKeyStats(pParse, p, pRec, 0, a);
          iNew = a[0] + ((pLower->eOperator & WO_GT) ? a[1] : 0);
          if( iNew>iLower ) iLower = iNew;
          nOut--;
          pLower = 0;
        }
      }

      /* If possible, improve on the iUpper estimate using ($P:$U). */
      if( pUpper ){
        int bOk;                    /* True if value is extracted from pExpr */
        Expr *pExpr = pUpper->pExpr->pRight;
        assert( (pUpper->eOperator & (WO_LT|WO_LE))!=0 );
        rc = sqlite3Stat4ProbeSetValue(pParse, p, &pRec, pExpr, aff, nEq, &bOk);
        if( rc==SQLITE_OK && bOk ){
          tRowcnt iNew;
          whereKeyStats(pParse, p, pRec, 1, a);
          iNew = a[0] + ((pUpper->eOperator & WO_LE) ? a[1] : 0);
          if( iNew<iUpper ) iUpper = iNew;
          nOut--;
          pUpper = 0;
        }
      }

      pBuilder->pRec = pRec;
................................................................................
  sqlite3StrAccumAppendAll(pStr, zColumn);
  sqlite3StrAccumAppend(pStr, zOp, 1);
  sqlite3StrAccumAppend(pStr, "?", 1);
}

/*
** Argument pLevel describes a strategy for scanning table pTab. This 
** function returns a pointer to a string buffer containing a description
** of the subset of table rows scanned by the strategy in the form of an
** SQL expression. Or, if all rows are scanned, NULL is returned.
**
** For example, if the query:
**
**   SELECT * FROM t1 WHERE a=1 AND b>2;
**
** is run and there is an index on (a, b), then this function returns a
** string similar to:
**
**   "a=? AND b>?"
**
** The returned pointer points to memory obtained from sqlite3DbMalloc().
** It is the responsibility of the caller to free the buffer when it is
** no longer required.
*/
static char *explainIndexRange(sqlite3 *db, WhereLoop *pLoop, Table *pTab){
  Index *pIndex = pLoop->u.btree.pIndex;
  u16 nEq = pLoop->u.btree.nEq;
  u16 nSkip = pLoop->u.btree.nSkip;
  int i, j;
  Column *aCol = pTab->aCol;
  i16 *aiColumn = pIndex->aiColumn;
  StrAccum txt;

  if( nEq==0 && (pLoop->wsFlags & (WHERE_BTM_LIMIT|WHERE_TOP_LIMIT))==0 ){
    return 0;
  }
  sqlite3StrAccumInit(&txt, 0, 0, SQLITE_MAX_LENGTH);
  txt.db = db;
  sqlite3StrAccumAppend(&txt, " (", 2);
  for(i=0; i<nEq; i++){
    char *z = aiColumn[i] < 0 ? "rowid" : aCol[aiColumn[i]].zName;
    if( i>=nSkip ){
      explainAppendTerm(&txt, i, z, "=");
    }else{
      if( i ) sqlite3StrAccumAppend(&txt, " AND ", 5);
      sqlite3StrAccumAppend(&txt, "ANY(", 4);
      sqlite3StrAccumAppendAll(&txt, z);
      sqlite3StrAccumAppend(&txt, ")", 1);
    }
  }

  j = i;
  if( pLoop->wsFlags&WHERE_BTM_LIMIT ){
    char *z = aiColumn[j] < 0 ? "rowid" : aCol[aiColumn[j]].zName;
    explainAppendTerm(&txt, i++, z, ">");
  }
  if( pLoop->wsFlags&WHERE_TOP_LIMIT ){
    char *z = aiColumn[j] < 0 ? "rowid" : aCol[aiColumn[j]].zName;
    explainAppendTerm(&txt, i, z, "<");
  }
  sqlite3StrAccumAppend(&txt, ")", 1);
  return sqlite3StrAccumFinish(&txt);
}

/*
** This function is a no-op unless currently processing an EXPLAIN QUERY PLAN
** command. If the query being compiled is an EXPLAIN QUERY PLAN, a single
** record is added to the output to describe the table scan strategy in 
** pLevel.
................................................................................
#ifndef SQLITE_DEBUG
  if( pParse->explain==2 )
#endif
  {
    struct SrcList_item *pItem = &pTabList->a[pLevel->iFrom];
    Vdbe *v = pParse->pVdbe;      /* VM being constructed */
    sqlite3 *db = pParse->db;     /* Database handle */
    char *zMsg;                   /* Text to add to EQP output */
    int iId = pParse->iSelectId;  /* Select id (left-most output column) */
    int isSearch;                 /* True for a SEARCH. False for SCAN. */
    WhereLoop *pLoop;             /* The controlling WhereLoop object */
    u32 flags;                    /* Flags that describe this loop */




    pLoop = pLevel->pWLoop;
    flags = pLoop->wsFlags;
    if( (flags&WHERE_MULTI_OR) || (wctrlFlags&WHERE_ONETABLE_ONLY) ) return;

    isSearch = (flags&(WHERE_BTM_LIMIT|WHERE_TOP_LIMIT))!=0
            || ((flags&WHERE_VIRTUALTABLE)==0 && (pLoop->u.btree.nEq>0))
            || (wctrlFlags&(WHERE_ORDERBY_MIN|WHERE_ORDERBY_MAX));

    zMsg = sqlite3MPrintf(db, "%s", isSearch?"SEARCH":"SCAN");


    if( pItem->pSelect ){
      zMsg = sqlite3MAppendf(db, zMsg, "%s SUBQUERY %d", zMsg,pItem->iSelectId);

    }else{
      zMsg = sqlite3MAppendf(db, zMsg, "%s TABLE %s", zMsg, pItem->zName);

    }

    if( pItem->zAlias ){
      zMsg = sqlite3MAppendf(db, zMsg, "%s AS %s", zMsg, pItem->zAlias);
    }
    if( (flags & (WHERE_IPK|WHERE_VIRTUALTABLE))==0
     && ALWAYS(pLoop->u.btree.pIndex!=0)
    ){
      const char *zFmt;



      Index *pIdx = pLoop->u.btree.pIndex;
      char *zWhere = explainIndexRange(db, pLoop, pItem->pTab);
      assert( !(flags&WHERE_AUTO_INDEX) || (flags&WHERE_IDX_ONLY) );
      if( !HasRowid(pItem->pTab) && IsPrimaryKeyIndex(pIdx) ){
        zFmt = zWhere ? "%s USING PRIMARY KEY%.0s%s" : "%s%.0s%s";


      }else if( flags & WHERE_AUTO_INDEX ){
        zFmt = "%s USING AUTOMATIC COVERING INDEX%.0s%s";
      }else if( flags & WHERE_IDX_ONLY ){
        zFmt = "%s USING COVERING INDEX %s%s";
      }else{
        zFmt = "%s USING INDEX %s%s";

      }
      zMsg = sqlite3MAppendf(db, zMsg, zFmt, zMsg, pIdx->zName, zWhere);
      sqlite3DbFree(db, zWhere);
    }else if( (flags & WHERE_IPK)!=0 && (flags & WHERE_CONSTRAINT)!=0 ){
      zMsg = sqlite3MAppendf(db, zMsg, "%s USING INTEGER PRIMARY KEY", zMsg);





      if( flags&(WHERE_COLUMN_EQ|WHERE_COLUMN_IN) ){
        zMsg = sqlite3MAppendf(db, zMsg, "%s (rowid=?)", zMsg);

      }else if( (flags&WHERE_BOTH_LIMIT)==WHERE_BOTH_LIMIT ){
        zMsg = sqlite3MAppendf(db, zMsg, "%s (rowid>? AND rowid<?)", zMsg);
      }else if( flags&WHERE_BTM_LIMIT ){
        zMsg = sqlite3MAppendf(db, zMsg, "%s (rowid>?)", zMsg);


      }else if( ALWAYS(flags&WHERE_TOP_LIMIT) ){
        zMsg = sqlite3MAppendf(db, zMsg, "%s (rowid<?)", zMsg);

      }


    }
#ifndef SQLITE_OMIT_VIRTUALTABLE
    else if( (flags & WHERE_VIRTUALTABLE)!=0 ){
      zMsg = sqlite3MAppendf(db, zMsg, "%s VIRTUAL TABLE INDEX %d:%s", zMsg,
                  pLoop->u.vtab.idxNum, pLoop->u.vtab.idxStr);
    }
#endif
    zMsg = sqlite3MAppendf(db, zMsg, "%s", zMsg);







    sqlite3VdbeAddOp4(v, OP_Explain, iId, iLevel, iFrom, zMsg, P4_DYNAMIC);
  }
}
#else
# define explainOneScan(u,v,w,x,y,z)
#endif /* SQLITE_OMIT_EXPLAIN */

................................................................................
      }
    }

    /* Run a separate WHERE clause for each term of the OR clause.  After
    ** eliminating duplicates from other WHERE clauses, the action for each
    ** sub-WHERE clause is to to invoke the main loop body as a subroutine.
    */
    wctrlFlags =  WHERE_OMIT_OPEN_CLOSE | WHERE_AND_ONLY |

                  WHERE_FORCE_TABLE | WHERE_ONETABLE_ONLY;
    for(ii=0; ii<pOrWc->nTerm; ii++){
      WhereTerm *pOrTerm = &pOrWc->a[ii];
      if( pOrTerm->leftCursor==iCur || (pOrTerm->eOperator & WO_AND)!=0 ){
        WhereInfo *pSubWInfo;           /* Info for single OR-term scan */
        Expr *pOrExpr = pOrTerm->pExpr; /* Current OR clause term */
        int j1 = 0;                     /* Address of jump operation */
        if( pAndExpr && !ExprHasProperty(pOrExpr, EP_FromJoin) ){
          pAndExpr->pLeft = pOrExpr;
          pOrExpr = pAndExpr;
        }
        /* Loop through table entries that match term pOrTerm. */

        pSubWInfo = sqlite3WhereBegin(pParse, pOrTab, pOrExpr, 0, 0,
                                      wctrlFlags, iCovCur);
        assert( pSubWInfo || pParse->nErr || db->mallocFailed );
        if( pSubWInfo ){
          WhereLoop *pSubLoop;
          explainOneScan(
              pParse, pOrTab, &pSubWInfo->a[0], iLevel, pLevel->iFrom, 0
................................................................................
      pTerm->wtFlags |= TERM_CODED;
    }
  }

  return pLevel->notReady;
}

#if defined(WHERETRACE_ENABLED) && defined(SQLITE_ENABLE_TREE_EXPLAIN)
/*
** Generate "Explanation" text for a WhereTerm.
*/
static void whereExplainTerm(Vdbe *v, WhereTerm *pTerm){



  char zType[4];
  memcpy(zType, "...", 4);
  if( pTerm->wtFlags & TERM_VIRTUAL ) zType[0] = 'V';
  if( pTerm->eOperator & WO_EQUIV  ) zType[1] = 'E';
  if( ExprHasProperty(pTerm->pExpr, EP_FromJoin) ) zType[2] = 'L';
  sqlite3ExplainPrintf(v, "%s ", zType);



  sqlite3ExplainExpr(v, pTerm->pExpr);
}
#endif /* WHERETRACE_ENABLED && SQLITE_ENABLE_TREE_EXPLAIN */



#ifdef WHERETRACE_ENABLED
/*
** Print a WhereLoop object for debugging purposes
*/
static void whereLoopPrint(WhereLoop *p, WhereClause *pWC){
  WhereInfo *pWInfo = pWC->pWInfo;
................................................................................
  }
  if( p->wsFlags & WHERE_SKIPSCAN ){
    sqlite3DebugPrintf(" f %05x %d-%d", p->wsFlags, p->nLTerm,p->u.btree.nSkip);
  }else{
    sqlite3DebugPrintf(" f %05x N %d", p->wsFlags, p->nLTerm);
  }
  sqlite3DebugPrintf(" cost %d,%d,%d\n", p->rSetup, p->rRun, p->nOut);
#ifdef SQLITE_ENABLE_TREE_EXPLAIN
  /* If the 0x100 bit of wheretracing is set, then show all of the constraint
  ** expressions in the WhereLoop.aLTerm[] array.
  */
  if( p->nLTerm && (sqlite3WhereTrace & 0x100)!=0 ){  /* WHERETRACE 0x100 */
    int i;
    Vdbe *v = pWInfo->pParse->pVdbe;
    sqlite3ExplainBegin(v);
    for(i=0; i<p->nLTerm; i++){
      WhereTerm *pTerm = p->aLTerm[i];
      if( pTerm==0 ) continue;
      sqlite3ExplainPrintf(v, "  (%d) #%-2d ", i+1, (int)(pTerm-pWC->a));
      sqlite3ExplainPush(v);
      whereExplainTerm(v, pTerm);
      sqlite3ExplainPop(v);
      sqlite3ExplainNL(v);
    }
    sqlite3ExplainFinish(v);
    sqlite3DebugPrintf("%s", sqlite3VdbeExplanation(v));
  }
#endif
}
#endif

/*
** Convert bulk memory into a valid WhereLoop that can be passed
** to whereLoopClear harmlessly.
*/
................................................................................
  ppPrev = whereLoopFindLesser(&pWInfo->pLoops, pTemplate);

  if( ppPrev==0 ){
    /* There already exists a WhereLoop on the list that is better
    ** than pTemplate, so just ignore pTemplate */
#if WHERETRACE_ENABLED /* 0x8 */
    if( sqlite3WhereTrace & 0x8 ){
      sqlite3DebugPrintf("ins-noop: ");
      whereLoopPrint(pTemplate, pBuilder->pWC);
    }
#endif
    return SQLITE_OK;  
  }else{
    p = *ppPrev;
  }
................................................................................
  /* If we reach this point it means that either p[] should be overwritten
  ** with pTemplate[] if p[] exists, or if p==NULL then allocate a new
  ** WhereLoop and insert it.
  */
#if WHERETRACE_ENABLED /* 0x8 */
  if( sqlite3WhereTrace & 0x8 ){
    if( p!=0 ){
      sqlite3DebugPrintf("ins-del:  ");
      whereLoopPrint(p, pBuilder->pWC);
    }
    sqlite3DebugPrintf("ins-new:  ");
    whereLoopPrint(pTemplate, pBuilder->pWC);
  }
#endif
  if( p==0 ){
    /* Allocate a new WhereLoop to add to the end of the list */
    *ppPrev = p = sqlite3DbMallocRaw(db, sizeof(WhereLoop));
    if( p==0 ) return SQLITE_NOMEM;
................................................................................
      ppTail = whereLoopFindLesser(ppTail, pTemplate);
      if( ppTail==0 ) break;
      pToDel = *ppTail;
      if( pToDel==0 ) break;
      *ppTail = pToDel->pNextLoop;
#if WHERETRACE_ENABLED /* 0x8 */
      if( sqlite3WhereTrace & 0x8 ){
        sqlite3DebugPrintf("ins-del:  ");
        whereLoopPrint(pToDel, pBuilder->pWC);
      }
#endif
      whereLoopDelete(db, pToDel);
    }
  }
  whereLoopXfer(db, p, pTemplate);
................................................................................
    pNew->u.btree.nEq++;
    pNew->u.btree.nSkip++;
    pNew->aLTerm[pNew->nLTerm++] = 0;
    pNew->wsFlags |= WHERE_SKIPSCAN;
    nIter = pProbe->aiRowLogEst[saved_nEq] - pProbe->aiRowLogEst[saved_nEq+1];
    if( pTerm ){
      /* TUNING:  When estimating skip-scan for a term that is also indexable,
      ** increase the cost of the skip-scan by 2x, to make it a little less
      ** desirable than the regular index lookup. */
      nIter += 10;  assert( 10==sqlite3LogEst(2) );
    }
    pNew->nOut -= nIter;



    whereLoopAddBtreeIndex(pBuilder, pSrc, pProbe, nIter + nInMul);
    pNew->nOut = saved_nOut;
    pNew->u.btree.nEq = saved_nEq;
    pNew->u.btree.nSkip = saved_nSkip;
  }
  for(; rc==SQLITE_OK && pTerm!=0; pTerm = whereScanNext(&scan)){
    u16 eOp = pTerm->eOperator;   /* Shorthand for pTerm->eOperator */
................................................................................

  if( pIndex->bUnordered ) return 0;
  if( (pOB = pBuilder->pWInfo->pOrderBy)==0 ) return 0;
  for(ii=0; ii<pOB->nExpr; ii++){
    Expr *pExpr = sqlite3ExprSkipCollate(pOB->a[ii].pExpr);
    if( pExpr->op!=TK_COLUMN ) return 0;
    if( pExpr->iTable==iCursor ){

      for(jj=0; jj<pIndex->nKeyCol; jj++){
        if( pExpr->iColumn==pIndex->aiColumn[jj] ) return 1;
      }
    }
  }
  return 0;
}
................................................................................
      if( termCanDriveIndex(pTerm, pSrc, 0) ){
        pNew->u.btree.nEq = 1;
        pNew->u.btree.nSkip = 0;
        pNew->u.btree.pIndex = 0;
        pNew->nLTerm = 1;
        pNew->aLTerm[0] = pTerm;
        /* TUNING: One-time cost for computing the automatic index is
        ** approximately 7*N*log2(N) where N is the number of rows in
        ** the table being indexed. */





        pNew->rSetup = rLogSize + rSize + 28;  assert( 28==sqlite3LogEst(7) );



        ApplyCostMultiplier(pNew->rSetup, pTab->costMult);
        /* TUNING: Each index lookup yields 20 rows in the table.  This
        ** is more than the usual guess of 10 rows, since we have no way
        ** of knowing how selective the index will ultimately be.  It would
        ** not be unreasonable to make this value much larger. */
        pNew->nOut = 43;  assert( 43==sqlite3LogEst(20) );
        pNew->rRun = sqlite3LogEstAdd(rLogSize,pNew->nOut);
................................................................................
  int iCur;
  WhereClause tempWC;
  WhereLoopBuilder sSubBuild;
  WhereOrSet sSum, sCur;
  struct SrcList_item *pItem;
  
  pWC = pBuilder->pWC;
  if( pWInfo->wctrlFlags & WHERE_AND_ONLY ) return SQLITE_OK;
  pWCEnd = pWC->a + pWC->nTerm;
  pNew = pBuilder->pNew;
  memset(&sSum, 0, sizeof(sSum));
  pItem = pWInfo->pTabList->a + pNew->iTab;
  iCur = pItem->iCursor;

  for(pTerm=pWC->a; pTerm<pWCEnd && rc==SQLITE_OK; pTerm++){
................................................................................
      int once = 1;
      int i, j;
    
      sSubBuild = *pBuilder;
      sSubBuild.pOrderBy = 0;
      sSubBuild.pOrSet = &sCur;


      for(pOrTerm=pOrWC->a; pOrTerm<pOrWCEnd; pOrTerm++){
        if( (pOrTerm->eOperator & WO_AND)!=0 ){
          sSubBuild.pWC = &pOrTerm->u.pAndInfo->wc;
        }else if( pOrTerm->leftCursor==iCur ){
          tempWC.pWInfo = pWC->pWInfo;
          tempWC.pOuter = pWC;
          tempWC.op = TK_AND;
................................................................................
          tempWC.nTerm = 1;
          tempWC.a = pOrTerm;
          sSubBuild.pWC = &tempWC;
        }else{
          continue;
        }
        sCur.n = 0;









#ifndef SQLITE_OMIT_VIRTUALTABLE
        if( IsVirtual(pItem->pTab) ){
          rc = whereLoopAddVirtual(&sSubBuild, mExtra);
        }else
#endif
        {
          rc = whereLoopAddBtree(&sSubBuild, mExtra);
        }



        assert( rc==SQLITE_OK || sCur.n==0 );
        if( sCur.n==0 ){
          sSum.n = 0;
          break;
        }else if( once ){
          whereOrMove(&sSum, &sCur);
          once = 0;
................................................................................
        ** the planner may elect to "OR" together a full-table scan and an
        ** index lookup. And other similarly odd results.  */
        pNew->rRun = sSum.a[i].rRun + 1;
        pNew->nOut = sSum.a[i].nOut;
        pNew->prereq = sSum.a[i].prereq;
        rc = whereLoopInsert(pBuilder, pNew);
      }

    }
  }
  return rc;
}

/*
** Add all WhereLoop objects for all tables 
................................................................................
            pColl = sqlite3ExprCollSeq(pWInfo->pParse, pOrderBy->a[i].pExpr);
            if( !pColl ) pColl = db->pDfltColl;
            if( sqlite3StrICmp(pColl->zName, pIndex->azColl[j])!=0 ) continue;
          }
          isMatch = 1;
          break;
        }
        if( isMatch && (pWInfo->wctrlFlags & WHERE_GROUPBY)==0 ){
          /* Make sure the sort order is compatible in an ORDER BY clause.
          ** Sort order is irrelevant for a GROUP BY clause. */
          if( revSet ){
            if( (rev ^ revIdx)!=pOrderBy->a[i].sortOrder ) isMatch = 0;
          }else{
            rev = revIdx ^ pOrderBy->a[i].sortOrder;
            if( rev ) *pRevMask |= MASKBIT(iLoop);
................................................................................
      pWInfo->nOBSat = pFrom->isOrdered;
      if( pWInfo->nOBSat<0 ) pWInfo->nOBSat = 0;
      pWInfo->revMask = pFrom->revLoop;
    }
    if( (pWInfo->wctrlFlags & WHERE_SORTBYGROUP)
        && pWInfo->nOBSat==pWInfo->pOrderBy->nExpr
    ){
      Bitmask notUsed = 0;
      int nOrder = wherePathSatisfiesOrderBy(pWInfo, pWInfo->pOrderBy, 
          pFrom, 0, nLoop-1, pFrom->aLoop[nLoop-1], &notUsed
      );
      assert( pWInfo->sorted==0 );
      pWInfo->sorted = (nOrder==pWInfo->pOrderBy->nExpr);



    }
  }


  pWInfo->nRowOut = pFrom->nRow;

  /* Free temporary memory and return success */
................................................................................
      pWInfo->wctrlFlags |= WHERE_DISTINCTBY;
      pWInfo->pOrderBy = pResultSet;
    }
  }

  /* Construct the WhereLoop objects */
  WHERETRACE(0xffff,("*** Optimizer Start ***\n"));

  /* Display all terms of the WHERE clause */
#if defined(WHERETRACE_ENABLED) && defined(SQLITE_ENABLE_TREE_EXPLAIN)
  if( sqlite3WhereTrace & 0x100 ){
    int i;
    Vdbe *v = pParse->pVdbe;
    sqlite3ExplainBegin(v);
    for(i=0; i<sWLB.pWC->nTerm; i++){
      sqlite3ExplainPrintf(v, "#%-2d ", i);
      sqlite3ExplainPush(v);
      whereExplainTerm(v, &sWLB.pWC->a[i]);
      sqlite3ExplainPop(v);
      sqlite3ExplainNL(v);
    }
    sqlite3ExplainFinish(v);
    sqlite3DebugPrintf("%s", sqlite3VdbeExplanation(v));
  }
#endif

  if( nTabList!=1 || whereShortCut(&sWLB)==0 ){
    rc = whereLoopAddAll(&sWLB);
    if( rc ) goto whereBeginError;
  
    /* Display all of the WhereLoop objects if wheretrace is enabled */
#ifdef WHERETRACE_ENABLED /* !=0 */
    if( sqlite3WhereTrace ){

  assert( TK_GT>TK_EQ && TK_GT<TK_GE );
  assert( TK_LT>TK_EQ && TK_LT<TK_GE );
  assert( TK_LE>TK_EQ && TK_LE<TK_GE );
  assert( TK_GE==TK_EQ+4 );
  return op==TK_IN || (op>=TK_EQ && op<=TK_GE) || op==TK_ISNULL;
}






/*
** Commute a comparison operator.  Expressions of the form "X op Y"
** are converted into "Y op X".
**
** If left/right precedence rules come into play when determining the
** collating sequence, then COLLATE operators are adjusted to ensure
** that the collating sequence does not change.  For example:
................................................................................
      }else{
        /* Note: this call could be optimized away - since the same values must 
        ** have been requested when testing key $P in whereEqualScanEst().  */
        whereKeyStats(pParse, p, pRec, 0, a);
        iLower = a[0];
        iUpper = a[0] + a[1];
      }

      assert( pLower==0 || (pLower->eOperator & (WO_GT|WO_GE))!=0 );
      assert( pUpper==0 || (pUpper->eOperator & (WO_LT|WO_LE))!=0 );
      assert( p->aSortOrder!=0 );
      if( p->aSortOrder[nEq] ){
        /* The roles of pLower and pUpper are swapped for a DESC index */
        SWAP(WhereTerm*, pLower, pUpper);
      }

      /* If possible, improve on the iLower estimate using ($P:$L). */
      if( pLower ){
        int bOk;                    /* True if value is extracted from pExpr */
        Expr *pExpr = pLower->pExpr->pRight;

        rc = sqlite3Stat4ProbeSetValue(pParse, p, &pRec, pExpr, aff, nEq, &bOk);
        if( rc==SQLITE_OK && bOk ){
          tRowcnt iNew;
          whereKeyStats(pParse, p, pRec, 0, a);
          iNew = a[0] + ((pLower->eOperator & (WO_GT|WO_LE)) ? a[1] : 0);
          if( iNew>iLower ) iLower = iNew;
          nOut--;
          pLower = 0;
        }
      }

      /* If possible, improve on the iUpper estimate using ($P:$U). */
      if( pUpper ){
        int bOk;                    /* True if value is extracted from pExpr */
        Expr *pExpr = pUpper->pExpr->pRight;

        rc = sqlite3Stat4ProbeSetValue(pParse, p, &pRec, pExpr, aff, nEq, &bOk);
        if( rc==SQLITE_OK && bOk ){
          tRowcnt iNew;
          whereKeyStats(pParse, p, pRec, 1, a);
          iNew = a[0] + ((pUpper->eOperator & (WO_GT|WO_LE)) ? a[1] : 0);
          if( iNew<iUpper ) iUpper = iNew;
          nOut--;
          pUpper = 0;
        }
      }

      pBuilder->pRec = pRec;
................................................................................
  sqlite3StrAccumAppendAll(pStr, zColumn);
  sqlite3StrAccumAppend(pStr, zOp, 1);
  sqlite3StrAccumAppend(pStr, "?", 1);
}

/*
** Argument pLevel describes a strategy for scanning table pTab. This 
** function appends text to pStr that describes the subset of table
** rows scanned by the strategy in the form of an SQL expression.

**
** For example, if the query:
**
**   SELECT * FROM t1 WHERE a=1 AND b>2;
**
** is run and there is an index on (a, b), then this function returns a
** string similar to:
**
**   "a=? AND b>?"




*/
static void explainIndexRange(StrAccum *pStr, WhereLoop *pLoop, Table *pTab){
  Index *pIndex = pLoop->u.btree.pIndex;
  u16 nEq = pLoop->u.btree.nEq;
  u16 nSkip = pLoop->u.btree.nSkip;
  int i, j;
  Column *aCol = pTab->aCol;
  i16 *aiColumn = pIndex->aiColumn;


  if( nEq==0 && (pLoop->wsFlags&(WHERE_BTM_LIMIT|WHERE_TOP_LIMIT))==0 ) return;




  sqlite3StrAccumAppend(pStr, " (", 2);
  for(i=0; i<nEq; i++){
    char *z = aiColumn[i] < 0 ? "rowid" : aCol[aiColumn[i]].zName;
    if( i>=nSkip ){
      explainAppendTerm(pStr, i, z, "=");
    }else{
      if( i ) sqlite3StrAccumAppend(pStr, " AND ", 5);
      sqlite3XPrintf(pStr, 0, "ANY(%s)", z);


    }
  }

  j = i;
  if( pLoop->wsFlags&WHERE_BTM_LIMIT ){
    char *z = aiColumn[j] < 0 ? "rowid" : aCol[aiColumn[j]].zName;
    explainAppendTerm(pStr, i++, z, ">");
  }
  if( pLoop->wsFlags&WHERE_TOP_LIMIT ){
    char *z = aiColumn[j] < 0 ? "rowid" : aCol[aiColumn[j]].zName;
    explainAppendTerm(pStr, i, z, "<");
  }
  sqlite3StrAccumAppend(pStr, ")", 1);

}

/*
** This function is a no-op unless currently processing an EXPLAIN QUERY PLAN
** command. If the query being compiled is an EXPLAIN QUERY PLAN, a single
** record is added to the output to describe the table scan strategy in 
** pLevel.
................................................................................
#ifndef SQLITE_DEBUG
  if( pParse->explain==2 )
#endif
  {
    struct SrcList_item *pItem = &pTabList->a[pLevel->iFrom];
    Vdbe *v = pParse->pVdbe;      /* VM being constructed */
    sqlite3 *db = pParse->db;     /* Database handle */

    int iId = pParse->iSelectId;  /* Select id (left-most output column) */
    int isSearch;                 /* True for a SEARCH. False for SCAN. */
    WhereLoop *pLoop;             /* The controlling WhereLoop object */
    u32 flags;                    /* Flags that describe this loop */
    char *zMsg;                   /* Text to add to EQP output */
    StrAccum str;                 /* EQP output string */
    char zBuf[100];               /* Initial space for EQP output string */

    pLoop = pLevel->pWLoop;
    flags = pLoop->wsFlags;
    if( (flags&WHERE_MULTI_OR) || (wctrlFlags&WHERE_ONETABLE_ONLY) ) return;

    isSearch = (flags&(WHERE_BTM_LIMIT|WHERE_TOP_LIMIT))!=0
            || ((flags&WHERE_VIRTUALTABLE)==0 && (pLoop->u.btree.nEq>0))
            || (wctrlFlags&(WHERE_ORDERBY_MIN|WHERE_ORDERBY_MAX));

    sqlite3StrAccumInit(&str, zBuf, sizeof(zBuf), SQLITE_MAX_LENGTH);
    str.db = db;
    sqlite3StrAccumAppendAll(&str, isSearch ? "SEARCH" : "SCAN");
    if( pItem->pSelect ){

      sqlite3XPrintf(&str, 0, " SUBQUERY %d", pItem->iSelectId);
    }else{

      sqlite3XPrintf(&str, 0, " TABLE %s", pItem->zName);
    }

    if( pItem->zAlias ){
      sqlite3XPrintf(&str, 0, " AS %s", pItem->zAlias);
    }
    if( (flags & (WHERE_IPK|WHERE_VIRTUALTABLE))==0 ){


      const char *zFmt = 0;
      Index *pIdx;

      assert( pLoop->u.btree.pIndex!=0 );
      pIdx = pLoop->u.btree.pIndex;

      assert( !(flags&WHERE_AUTO_INDEX) || (flags&WHERE_IDX_ONLY) );
      if( !HasRowid(pItem->pTab) && IsPrimaryKeyIndex(pIdx) ){
        if( isSearch ){
          zFmt = "PRIMARY KEY";
        }
      }else if( flags & WHERE_AUTO_INDEX ){
        zFmt = "AUTOMATIC COVERING INDEX";
      }else if( flags & WHERE_IDX_ONLY ){
        zFmt = "COVERING INDEX %s";
      }else{

        zFmt = "INDEX %s";
      }


      if( zFmt ){
        sqlite3StrAccumAppend(&str, " USING ", 7);
        sqlite3XPrintf(&str, 0, zFmt, pIdx->zName);
        explainIndexRange(&str, pLoop, pItem->pTab);
      }
    }else if( (flags & WHERE_IPK)!=0 && (flags & WHERE_CONSTRAINT)!=0 ){
      const char *zRange;
      if( flags&(WHERE_COLUMN_EQ|WHERE_COLUMN_IN) ){

        zRange = "(rowid=?)";
      }else if( (flags&WHERE_BOTH_LIMIT)==WHERE_BOTH_LIMIT ){
        zRange = "(rowid>? AND rowid<?)";
      }else if( flags&WHERE_BTM_LIMIT ){

        zRange = "(rowid>?)";
      }else{
        assert( flags&WHERE_TOP_LIMIT);

        zRange = "(rowid<?)";
      }
      sqlite3StrAccumAppendAll(&str, " USING INTEGER PRIMARY KEY ");
      sqlite3StrAccumAppendAll(&str, zRange);
    }
#ifndef SQLITE_OMIT_VIRTUALTABLE
    else if( (flags & WHERE_VIRTUALTABLE)!=0 ){
      sqlite3XPrintf(&str, 0, " VIRTUAL TABLE INDEX %d:%s",
                  pLoop->u.vtab.idxNum, pLoop->u.vtab.idxStr);
    }
#endif
#ifdef SQLITE_EXPLAIN_ESTIMATED_ROWS
    if( pLoop->nOut>=10 ){
      sqlite3XPrintf(&str, 0, " (~%llu rows)", sqlite3LogEstToInt(pLoop->nOut));
    }else{
      sqlite3StrAccumAppend(&str, " (~1 row)", 9);
    }
#endif
    zMsg = sqlite3StrAccumFinish(&str);
    sqlite3VdbeAddOp4(v, OP_Explain, iId, iLevel, iFrom, zMsg, P4_DYNAMIC);
  }
}
#else
# define explainOneScan(u,v,w,x,y,z)
#endif /* SQLITE_OMIT_EXPLAIN */

................................................................................
      }
    }

    /* Run a separate WHERE clause for each term of the OR clause.  After
    ** eliminating duplicates from other WHERE clauses, the action for each
    ** sub-WHERE clause is to to invoke the main loop body as a subroutine.
    */
    wctrlFlags =  WHERE_OMIT_OPEN_CLOSE
                | WHERE_FORCE_TABLE
                | WHERE_ONETABLE_ONLY;
    for(ii=0; ii<pOrWc->nTerm; ii++){
      WhereTerm *pOrTerm = &pOrWc->a[ii];
      if( pOrTerm->leftCursor==iCur || (pOrTerm->eOperator & WO_AND)!=0 ){
        WhereInfo *pSubWInfo;           /* Info for single OR-term scan */
        Expr *pOrExpr = pOrTerm->pExpr; /* Current OR clause term */
        int j1 = 0;                     /* Address of jump operation */
        if( pAndExpr && !ExprHasProperty(pOrExpr, EP_FromJoin) ){
          pAndExpr->pLeft = pOrExpr;
          pOrExpr = pAndExpr;
        }
        /* Loop through table entries that match term pOrTerm. */
        WHERETRACE(0xffff, ("Subplan for OR-clause:\n"));
        pSubWInfo = sqlite3WhereBegin(pParse, pOrTab, pOrExpr, 0, 0,
                                      wctrlFlags, iCovCur);
        assert( pSubWInfo || pParse->nErr || db->mallocFailed );
        if( pSubWInfo ){
          WhereLoop *pSubLoop;
          explainOneScan(
              pParse, pOrTab, &pSubWInfo->a[0], iLevel, pLevel->iFrom, 0
................................................................................
      pTerm->wtFlags |= TERM_CODED;
    }
  }

  return pLevel->notReady;
}

#ifdef WHERETRACE_ENABLED
/*
** Print the content of a WhereTerm object
*/
static void whereTermPrint(WhereTerm *pTerm, int iTerm){
  if( pTerm==0 ){
    sqlite3DebugPrintf("TERM-%-3d NULL\n", iTerm);
  }else{
    char zType[4];
    memcpy(zType, "...", 4);
    if( pTerm->wtFlags & TERM_VIRTUAL ) zType[0] = 'V';
    if( pTerm->eOperator & WO_EQUIV  ) zType[1] = 'E';
    if( ExprHasProperty(pTerm->pExpr, EP_FromJoin) ) zType[2] = 'L';

    sqlite3DebugPrintf("TERM-%-3d %p %s cursor=%-3d prob=%-3d op=0x%03x\n",
                       iTerm, pTerm, zType, pTerm->leftCursor, pTerm->truthProb,
                       pTerm->eOperator);
    sqlite3TreeViewExpr(0, pTerm->pExpr, 0);
  }

}
#endif

#ifdef WHERETRACE_ENABLED
/*
** Print a WhereLoop object for debugging purposes
*/
static void whereLoopPrint(WhereLoop *p, WhereClause *pWC){
  WhereInfo *pWInfo = pWC->pWInfo;
................................................................................
  }
  if( p->wsFlags & WHERE_SKIPSCAN ){
    sqlite3DebugPrintf(" f %05x %d-%d", p->wsFlags, p->nLTerm,p->u.btree.nSkip);
  }else{
    sqlite3DebugPrintf(" f %05x N %d", p->wsFlags, p->nLTerm);
  }
  sqlite3DebugPrintf(" cost %d,%d,%d\n", p->rSetup, p->rRun, p->nOut);




  if( p->nLTerm && (sqlite3WhereTrace & 0x100)!=0 ){
    int i;


    for(i=0; i<p->nLTerm; i++){
      whereTermPrint(p->aLTerm[i], i);






    }


  }

}
#endif

/*
** Convert bulk memory into a valid WhereLoop that can be passed
** to whereLoopClear harmlessly.
*/
................................................................................
  ppPrev = whereLoopFindLesser(&pWInfo->pLoops, pTemplate);

  if( ppPrev==0 ){
    /* There already exists a WhereLoop on the list that is better
    ** than pTemplate, so just ignore pTemplate */
#if WHERETRACE_ENABLED /* 0x8 */
    if( sqlite3WhereTrace & 0x8 ){
      sqlite3DebugPrintf("   skip: ");
      whereLoopPrint(pTemplate, pBuilder->pWC);
    }
#endif
    return SQLITE_OK;  
  }else{
    p = *ppPrev;
  }
................................................................................
  /* If we reach this point it means that either p[] should be overwritten
  ** with pTemplate[] if p[] exists, or if p==NULL then allocate a new
  ** WhereLoop and insert it.
  */
#if WHERETRACE_ENABLED /* 0x8 */
  if( sqlite3WhereTrace & 0x8 ){
    if( p!=0 ){
      sqlite3DebugPrintf("replace: ");
      whereLoopPrint(p, pBuilder->pWC);
    }
    sqlite3DebugPrintf("    add: ");
    whereLoopPrint(pTemplate, pBuilder->pWC);
  }
#endif
  if( p==0 ){
    /* Allocate a new WhereLoop to add to the end of the list */
    *ppPrev = p = sqlite3DbMallocRaw(db, sizeof(WhereLoop));
    if( p==0 ) return SQLITE_NOMEM;
................................................................................
      ppTail = whereLoopFindLesser(ppTail, pTemplate);
      if( ppTail==0 ) break;
      pToDel = *ppTail;
      if( pToDel==0 ) break;
      *ppTail = pToDel->pNextLoop;
#if WHERETRACE_ENABLED /* 0x8 */
      if( sqlite3WhereTrace & 0x8 ){
        sqlite3DebugPrintf(" delete: ");
        whereLoopPrint(pToDel, pBuilder->pWC);
      }
#endif
      whereLoopDelete(db, pToDel);
    }
  }
  whereLoopXfer(db, p, pTemplate);
................................................................................
    pNew->u.btree.nEq++;
    pNew->u.btree.nSkip++;
    pNew->aLTerm[pNew->nLTerm++] = 0;
    pNew->wsFlags |= WHERE_SKIPSCAN;
    nIter = pProbe->aiRowLogEst[saved_nEq] - pProbe->aiRowLogEst[saved_nEq+1];
    if( pTerm ){
      /* TUNING:  When estimating skip-scan for a term that is also indexable,
      ** multiply the cost of the skip-scan by 2.0, to make it a little less
      ** desirable than the regular index lookup. */
      nIter += 10;  assert( 10==sqlite3LogEst(2) );
    }
    pNew->nOut -= nIter;
    /* TUNING:  Because uncertainties in the estimates for skip-scan queries,
    ** add a 1.375 fudge factor to make skip-scan slightly less likely. */
    nIter += 5;
    whereLoopAddBtreeIndex(pBuilder, pSrc, pProbe, nIter + nInMul);
    pNew->nOut = saved_nOut;
    pNew->u.btree.nEq = saved_nEq;
    pNew->u.btree.nSkip = saved_nSkip;
  }
  for(; rc==SQLITE_OK && pTerm!=0; pTerm = whereScanNext(&scan)){
    u16 eOp = pTerm->eOperator;   /* Shorthand for pTerm->eOperator */
................................................................................

  if( pIndex->bUnordered ) return 0;
  if( (pOB = pBuilder->pWInfo->pOrderBy)==0 ) return 0;
  for(ii=0; ii<pOB->nExpr; ii++){
    Expr *pExpr = sqlite3ExprSkipCollate(pOB->a[ii].pExpr);
    if( pExpr->op!=TK_COLUMN ) return 0;
    if( pExpr->iTable==iCursor ){
      if( pExpr->iColumn<0 ) return 1;
      for(jj=0; jj<pIndex->nKeyCol; jj++){
        if( pExpr->iColumn==pIndex->aiColumn[jj] ) return 1;
      }
    }
  }
  return 0;
}
................................................................................
      if( termCanDriveIndex(pTerm, pSrc, 0) ){
        pNew->u.btree.nEq = 1;
        pNew->u.btree.nSkip = 0;
        pNew->u.btree.pIndex = 0;
        pNew->nLTerm = 1;
        pNew->aLTerm[0] = pTerm;
        /* TUNING: One-time cost for computing the automatic index is
        ** estimated to be X*N*log2(N) where N is the number of rows in
        ** the table being indexed and where X is 7 (LogEst=28) for normal
        ** tables or 1.375 (LogEst=4) for views and subqueries.  The value
        ** of X is smaller for views and subqueries so that the query planner
        ** will be more aggressive about generating automatic indexes for
        ** those objects, since there is no opportunity to add schema
        ** indexes on subqueries and views. */
        pNew->rSetup = rLogSize + rSize + 4;
        if( pTab->pSelect==0 && (pTab->tabFlags & TF_Ephemeral)==0 ){
          pNew->rSetup += 24;
        }
        ApplyCostMultiplier(pNew->rSetup, pTab->costMult);
        /* TUNING: Each index lookup yields 20 rows in the table.  This
        ** is more than the usual guess of 10 rows, since we have no way
        ** of knowing how selective the index will ultimately be.  It would
        ** not be unreasonable to make this value much larger. */
        pNew->nOut = 43;  assert( 43==sqlite3LogEst(20) );
        pNew->rRun = sqlite3LogEstAdd(rLogSize,pNew->nOut);
................................................................................
  int iCur;
  WhereClause tempWC;
  WhereLoopBuilder sSubBuild;
  WhereOrSet sSum, sCur;
  struct SrcList_item *pItem;
  
  pWC = pBuilder->pWC;

  pWCEnd = pWC->a + pWC->nTerm;
  pNew = pBuilder->pNew;
  memset(&sSum, 0, sizeof(sSum));
  pItem = pWInfo->pTabList->a + pNew->iTab;
  iCur = pItem->iCursor;

  for(pTerm=pWC->a; pTerm<pWCEnd && rc==SQLITE_OK; pTerm++){
................................................................................
      int once = 1;
      int i, j;
    
      sSubBuild = *pBuilder;
      sSubBuild.pOrderBy = 0;
      sSubBuild.pOrSet = &sCur;

      WHERETRACE(0x200, ("Begin processing OR-clause %p\n", pTerm));
      for(pOrTerm=pOrWC->a; pOrTerm<pOrWCEnd; pOrTerm++){
        if( (pOrTerm->eOperator & WO_AND)!=0 ){
          sSubBuild.pWC = &pOrTerm->u.pAndInfo->wc;
        }else if( pOrTerm->leftCursor==iCur ){
          tempWC.pWInfo = pWC->pWInfo;
          tempWC.pOuter = pWC;
          tempWC.op = TK_AND;
................................................................................
          tempWC.nTerm = 1;
          tempWC.a = pOrTerm;
          sSubBuild.pWC = &tempWC;
        }else{
          continue;
        }
        sCur.n = 0;
#ifdef WHERETRACE_ENABLED
        WHERETRACE(0x200, ("OR-term %d of %p has %d subterms:\n", 
                   (int)(pOrTerm-pOrWC->a), pTerm, sSubBuild.pWC->nTerm));
        if( sqlite3WhereTrace & 0x400 ){
          for(i=0; i<sSubBuild.pWC->nTerm; i++){
            whereTermPrint(&sSubBuild.pWC->a[i], i);
          }
        }
#endif
#ifndef SQLITE_OMIT_VIRTUALTABLE
        if( IsVirtual(pItem->pTab) ){
          rc = whereLoopAddVirtual(&sSubBuild, mExtra);
        }else
#endif
        {
          rc = whereLoopAddBtree(&sSubBuild, mExtra);
        }
        if( rc==SQLITE_OK ){
          rc = whereLoopAddOr(&sSubBuild, mExtra);
        }
        assert( rc==SQLITE_OK || sCur.n==0 );
        if( sCur.n==0 ){
          sSum.n = 0;
          break;
        }else if( once ){
          whereOrMove(&sSum, &sCur);
          once = 0;
................................................................................
        ** the planner may elect to "OR" together a full-table scan and an
        ** index lookup. And other similarly odd results.  */
        pNew->rRun = sSum.a[i].rRun + 1;
        pNew->nOut = sSum.a[i].nOut;
        pNew->prereq = sSum.a[i].prereq;
        rc = whereLoopInsert(pBuilder, pNew);
      }
      WHERETRACE(0x200, ("End processing OR-clause %p\n", pTerm));
    }
  }
  return rc;
}

/*
** Add all WhereLoop objects for all tables 
................................................................................
            pColl = sqlite3ExprCollSeq(pWInfo->pParse, pOrderBy->a[i].pExpr);
            if( !pColl ) pColl = db->pDfltColl;
            if( sqlite3StrICmp(pColl->zName, pIndex->azColl[j])!=0 ) continue;
          }
          isMatch = 1;
          break;
        }
        if( isMatch && (wctrlFlags & WHERE_GROUPBY)==0 ){
          /* Make sure the sort order is compatible in an ORDER BY clause.
          ** Sort order is irrelevant for a GROUP BY clause. */
          if( revSet ){
            if( (rev ^ revIdx)!=pOrderBy->a[i].sortOrder ) isMatch = 0;
          }else{
            rev = revIdx ^ pOrderBy->a[i].sortOrder;
            if( rev ) *pRevMask |= MASKBIT(iLoop);
................................................................................
      pWInfo->nOBSat = pFrom->isOrdered;
      if( pWInfo->nOBSat<0 ) pWInfo->nOBSat = 0;
      pWInfo->revMask = pFrom->revLoop;
    }
    if( (pWInfo->wctrlFlags & WHERE_SORTBYGROUP)
        && pWInfo->nOBSat==pWInfo->pOrderBy->nExpr
    ){
      Bitmask revMask = 0;
      int nOrder = wherePathSatisfiesOrderBy(pWInfo, pWInfo->pOrderBy, 
          pFrom, 0, nLoop-1, pFrom->aLoop[nLoop-1], &revMask
      );
      assert( pWInfo->sorted==0 );
      if( nOrder==pWInfo->pOrderBy->nExpr ){
        pWInfo->sorted = 1;
        pWInfo->revMask = revMask;
      }
    }
  }


  pWInfo->nRowOut = pFrom->nRow;

  /* Free temporary memory and return success */
................................................................................
      pWInfo->wctrlFlags |= WHERE_DISTINCTBY;
      pWInfo->pOrderBy = pResultSet;
    }
  }

  /* Construct the WhereLoop objects */
  WHERETRACE(0xffff,("*** Optimizer Start ***\n"));
#if defined(WHERETRACE_ENABLED)
  /* Display all terms of the WHERE clause */

  if( sqlite3WhereTrace & 0x100 ){
    int i;


    for(i=0; i<sWLB.pWC->nTerm; i++){


      whereTermPrint(&sWLB.pWC->a[i], i);


    }


  }
#endif

  if( nTabList!=1 || whereShortCut(&sWLB)==0 ){
    rc = whereLoopAddAll(&sWLB);
    if( rc ) goto whereBeginError;
  
    /* Display all of the WhereLoop objects if wheretrace is enabled */
#ifdef WHERETRACE_ENABLED /* !=0 */
    if( sqlite3WhereTrace ){

# 2005 July 22
#
# 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 implements regression tests for SQLite library.
# This file implements tests for the ANALYZE command.
#
# $Id: analyze.test,v 1.9 2008/08/11 18:44:58 drh Exp $

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set ::testprefix analyzeD

ifcapable {!stat4} {
  finish_test
  return
}


# Set up a table with the following properties:
#
#    * Contains 1000 rows.
#    * Column a contains even integers between 0 and 18, inclusive (so that
#      a=? for any such integer matches 100 rows).
#    * Column b contains integers between 0 and 9, inclusive.
#    * Column c contains integers between 0 and 199, inclusive (so that
#      for any such integer, c=? matches 5 rows).
#    * Then add 7 rows with a new value for "a" - 3001. The stat4 table will
#      not contain any samples with a=3001.
#
do_execsql_test 1.0 {
  CREATE TABLE t1(a, b, c);
}
do_test 1.1 {
  for {set i 1} {$i < 1000} {incr i} {
    set c [expr $i % 200]
    execsql { INSERT INTO t1(a, b, c) VALUES( 2*($i/100), $i%10, $c ) }
  }

  execsql {
    INSERT INTO t1 VALUES(3001, 3001, 3001);
    INSERT INTO t1 VALUES(3001, 3001, 3002);
    INSERT INTO t1 VALUES(3001, 3001, 3003);
    INSERT INTO t1 VALUES(3001, 3001, 3004);
    INSERT INTO t1 VALUES(3001, 3001, 3005);
    INSERT INTO t1 VALUES(3001, 3001, 3006);
    INSERT INTO t1 VALUES(3001, 3001, 3007);

    CREATE INDEX t1_ab ON t1(a, b);
    CREATE INDEX t1_c ON t1(c);

    ANALYZE;
  }
} {}

# With full ANALYZE data, SQLite sees that c=150 (5 rows) is better than
# a=3001 (7 rows).
#
do_eqp_test 1.2 {
  SELECT * FROM t1 WHERE a=3001 AND c=150;
} {
  0 0 0 {SEARCH TABLE t1 USING INDEX t1_c (c=?)}
}

do_test 1.3 {
  execsql { DELETE FROM sqlite_stat1 }
  db close
  sqlite3 db test.db
} {}

# Without stat1, because 3001 is larger than all samples in the stat4
# table, SQLite things that a=3001 matches just 1 row. So it (incorrectly)
# chooses it over the c=150 index (5 rows). Even with stat1 data, things
# worked this way before commit [e6f7f97dbc].
#
do_eqp_test 1.4 {
  SELECT * FROM t1 WHERE a=3001 AND c=150;
} {
  0 0 0 {SEARCH TABLE t1 USING INDEX t1_ab (a=?)}
}

do_test 1.5 {
  execsql { 
    UPDATE t1 SET a=13 WHERE a = 3001;
    ANALYZE;
  }
} {}

do_eqp_test 1.6 {
  SELECT * FROM t1 WHERE a=13 AND c=150;
} {
  0 0 0 {SEARCH TABLE t1 USING INDEX t1_c (c=?)}
}

do_test 1.7 {
  execsql { DELETE FROM sqlite_stat1 }
  db close
  sqlite3 db test.db
} {}

# Same test as 1.4, except this time the 7 rows that match the a=? condition 
# do not feature larger values than all rows in the stat4 table. So SQLite
# gets this right, even without stat1 data.
do_eqp_test 1.8 {
  SELECT * FROM t1 WHERE a=13 AND c=150;
} {
  0 0 0 {SEARCH TABLE t1 USING INDEX t1_c (c=?)}
}

finish_test

# 2014-10-08
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements tests for using STAT4 information
# on a descending index in a range query.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set ::testprefix analyzeE

ifcapable {!stat4} {
  finish_test
  return
}

# Verify that range queries on an ASCENDING index will use the
# index only if the range covers only a small fraction of the
# entries.
#
do_execsql_test analyzeE-1.0 {
  CREATE TABLE t1(a,b);
  WITH RECURSIVE
    cnt(x) AS (VALUES(1000) UNION ALL SELECT x+1 FROM cnt WHERE x<2000)
  INSERT INTO t1(a,b) SELECT x, x FROM cnt;
  CREATE INDEX t1a ON t1(a);
  ANALYZE;
} {}
do_execsql_test analyzeE-1.1 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a BETWEEN 500 AND 2500;
} {/SCAN TABLE t1/}
do_execsql_test analyzeE-1.2 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a BETWEEN 2900 AND 3000;
} {/SEARCH TABLE t1 USING INDEX t1a/}
do_execsql_test analyzeE-1.3 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a BETWEEN 1700 AND 1750;
} {/SEARCH TABLE t1 USING INDEX t1a/}
do_execsql_test analyzeE-1.4 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a BETWEEN 1 AND 500
} {/SEARCH TABLE t1 USING INDEX t1a/}
do_execsql_test analyzeE-1.5 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a BETWEEN 3000 AND 3000000
} {/SEARCH TABLE t1 USING INDEX t1a/}
do_execsql_test analyzeE-1.6 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a<500
} {/SEARCH TABLE t1 USING INDEX t1a/}
do_execsql_test analyzeE-1.7 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a>2500
} {/SEARCH TABLE t1 USING INDEX t1a/}
do_execsql_test analyzeE-1.8 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a>1900
} {/SEARCH TABLE t1 USING INDEX t1a/}
do_execsql_test analyzeE-1.9 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a>1100
} {/SCAN TABLE t1/}
do_execsql_test analyzeE-1.10 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a<1100
} {/SEARCH TABLE t1 USING INDEX t1a/}
do_execsql_test analyzeE-1.11 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a<1900
} {/SCAN TABLE t1/}

# Verify that everything works the same on a DESCENDING index.
#
do_execsql_test analyzeE-2.0 {
  DROP INDEX t1a;
  CREATE INDEX t1a ON t1(a DESC);
  ANALYZE;
} {}
do_execsql_test analyzeE-2.1 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a BETWEEN 500 AND 2500;
} {/SCAN TABLE t1/}
do_execsql_test analyzeE-2.2 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a BETWEEN 2900 AND 3000;
} {/SEARCH TABLE t1 USING INDEX t1a/}
do_execsql_test analyzeE-2.3 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a BETWEEN 1700 AND 1750;
} {/SEARCH TABLE t1 USING INDEX t1a/}
do_execsql_test analyzeE-2.4 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a BETWEEN 1 AND 500
} {/SEARCH TABLE t1 USING INDEX t1a/}
do_execsql_test analyzeE-2.5 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a BETWEEN 3000 AND 3000000
} {/SEARCH TABLE t1 USING INDEX t1a/}
do_execsql_test analyzeE-2.6 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a<500
} {/SEARCH TABLE t1 USING INDEX t1a/}
do_execsql_test analyzeE-2.7 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a>2500
} {/SEARCH TABLE t1 USING INDEX t1a/}
do_execsql_test analyzeE-2.8 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a>1900
} {/SEARCH TABLE t1 USING INDEX t1a/}
do_execsql_test analyzeE-2.9 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a>1100
} {/SCAN TABLE t1/}
do_execsql_test analyzeE-2.10 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a<1100
} {/SEARCH TABLE t1 USING INDEX t1a/}
do_execsql_test analyzeE-2.11 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a<1900
} {/SCAN TABLE t1/}

# Now do a range query on the second term of an ASCENDING index
# where the first term is constrained by equality.
#
do_execsql_test analyzeE-3.0 {
  DROP TABLE t1;
  CREATE TABLE t1(a,b,c);
  WITH RECURSIVE
    cnt(x) AS (VALUES(1000) UNION ALL SELECT x+1 FROM cnt WHERE x<2000)
  INSERT INTO t1(a,b,c) SELECT x, x, 123 FROM cnt;
  CREATE INDEX t1ca ON t1(c,a);
  ANALYZE;
} {}
do_execsql_test analyzeE-3.1 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a BETWEEN 500 AND 2500 AND c=123;
} {/SCAN TABLE t1/}
do_execsql_test analyzeE-3.2 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a BETWEEN 2900 AND 3000 AND c=123;
} {/SEARCH TABLE t1 USING INDEX t1ca/}
do_execsql_test analyzeE-3.3 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a BETWEEN 1700 AND 1750 AND c=123;
} {/SEARCH TABLE t1 USING INDEX t1ca/}
do_execsql_test analyzeE-3.4 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a BETWEEN 1 AND 500 AND c=123
} {/SEARCH TABLE t1 USING INDEX t1ca/}
do_execsql_test analyzeE-3.5 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a BETWEEN 3000 AND 3000000 AND c=123
} {/SEARCH TABLE t1 USING INDEX t1ca/}
do_execsql_test analyzeE-3.6 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a<500 AND c=123
} {/SEARCH TABLE t1 USING INDEX t1ca/}
do_execsql_test analyzeE-3.7 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a>2500 AND c=123
} {/SEARCH TABLE t1 USING INDEX t1ca/}
do_execsql_test analyzeE-3.8 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a>1900 AND c=123
} {/SEARCH TABLE t1 USING INDEX t1ca/}
do_execsql_test analyzeE-3.9 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a>1100 AND c=123
} {/SCAN TABLE t1/}
do_execsql_test analyzeE-3.10 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a<1100 AND c=123
} {/SEARCH TABLE t1 USING INDEX t1ca/}
do_execsql_test analyzeE-3.11 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a<1900 AND c=123
} {/SCAN TABLE t1/}

# Repeat the 3.x tests using a DESCENDING index
#
do_execsql_test analyzeE-4.0 {
  DROP INDEX t1ca;
  CREATE INDEX t1ca ON t1(c ASC,a DESC);
  ANALYZE;
} {}
do_execsql_test analyzeE-4.1 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a BETWEEN 500 AND 2500 AND c=123;
} {/SCAN TABLE t1/}
do_execsql_test analyzeE-4.2 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a BETWEEN 2900 AND 3000 AND c=123;
} {/SEARCH TABLE t1 USING INDEX t1ca/}
do_execsql_test analyzeE-4.3 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a BETWEEN 1700 AND 1750 AND c=123;
} {/SEARCH TABLE t1 USING INDEX t1ca/}
do_execsql_test analyzeE-4.4 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a BETWEEN 1 AND 500 AND c=123
} {/SEARCH TABLE t1 USING INDEX t1ca/}
do_execsql_test analyzeE-4.5 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a BETWEEN 3000 AND 3000000 AND c=123
} {/SEARCH TABLE t1 USING INDEX t1ca/}
do_execsql_test analyzeE-4.6 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a<500 AND c=123
} {/SEARCH TABLE t1 USING INDEX t1ca/}
do_execsql_test analyzeE-4.7 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a>2500 AND c=123
} {/SEARCH TABLE t1 USING INDEX t1ca/}
do_execsql_test analyzeE-4.8 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a>1900 AND c=123
} {/SEARCH TABLE t1 USING INDEX t1ca/}
do_execsql_test analyzeE-4.9 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a>1100 AND c=123
} {/SCAN TABLE t1/}
do_execsql_test analyzeE-4.10 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a<1100 AND c=123
} {/SEARCH TABLE t1 USING INDEX t1ca/}
do_execsql_test analyzeE-4.11 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a<1900 AND c=123
} {/SCAN TABLE t1/}

finish_test

  EXPLAIN QUERY PLAN
  SELECT * FROM 
        data JOIN mimetypes ON (data.mimetype_id=mimetypes._id) 
             JOIN raw_contacts ON (data.raw_contact_id=raw_contacts._id) 
             JOIN accounts ON (raw_contacts.account_id=accounts._id)
   WHERE mimetypes._id=10 AND data14 IS NOT NULL;
} {/SEARCH TABLE data .*SEARCH TABLE raw_contacts/}


































































































finish_test

  EXPLAIN QUERY PLAN
  SELECT * FROM 
        data JOIN mimetypes ON (data.mimetype_id=mimetypes._id) 
             JOIN raw_contacts ON (data.raw_contact_id=raw_contacts._id) 
             JOIN accounts ON (raw_contacts.account_id=accounts._id)
   WHERE mimetypes._id=10 AND data14 IS NOT NULL;
} {/SEARCH TABLE data .*SEARCH TABLE raw_contacts/}

# Another test case from an important user of SQLite.  The key feature of
# this test is that the "aggindex" subquery should make use of an
# automatic index.  If it does, the query is fast.  If it does not, the
# query is deathly slow.  It worked OK in 3.7.17 but started going slow
# with version 3.8.0.  The problem was fixed for 3.8.7 by reducing the
# cost estimate for automatic indexes on views and subqueries.
#
db close
forcedelete test.db
sqlite3 db test.db
do_execsql_test autoindex1-900 {
  CREATE TABLE messages (ROWID INTEGER PRIMARY KEY AUTOINCREMENT, message_id, document_id BLOB, in_reply_to, remote_id INTEGER, sender INTEGER, subject_prefix, subject INTEGER, date_sent INTEGER, date_received INTEGER, date_created INTEGER, date_last_viewed INTEGER, mailbox INTEGER, remote_mailbox INTEGER, original_mailbox INTEGER, flags INTEGER, read, flagged, size INTEGER, color, encoding, type INTEGER, pad, conversation_id INTEGER DEFAULT -1, snippet TEXT DEFAULT NULL, fuzzy_ancestor INTEGER DEFAULT NULL, automated_conversation INTEGER DEFAULT 0, root_status INTEGER DEFAULT -1, conversation_position INTEGER DEFAULT -1);
  CREATE INDEX date_index ON messages(date_received);
  CREATE INDEX date_last_viewed_index ON messages(date_last_viewed);
  CREATE INDEX date_created_index ON messages(date_created);
  CREATE INDEX message_message_id_mailbox_index ON messages(message_id, mailbox);
  CREATE INDEX message_document_id_index ON messages(document_id);
  CREATE INDEX message_read_index ON messages(read);
  CREATE INDEX message_flagged_index ON messages(flagged);
  CREATE INDEX message_mailbox_index ON messages(mailbox, date_received);
  CREATE INDEX message_remote_mailbox_index ON messages(remote_mailbox, remote_id);
  CREATE INDEX message_type_index ON messages(type);
  CREATE INDEX message_conversation_id_conversation_position_index ON messages(conversation_id, conversation_position);
  CREATE INDEX message_fuzzy_ancestor_index ON messages(fuzzy_ancestor);
  CREATE INDEX message_subject_fuzzy_ancestor_index ON messages(subject, fuzzy_ancestor);
  CREATE INDEX message_sender_subject_automated_conversation_index ON messages(sender, subject, automated_conversation);
  CREATE INDEX message_sender_index ON messages(sender);
  CREATE INDEX message_root_status ON messages(root_status);
  CREATE TABLE subjects (ROWID INTEGER PRIMARY KEY, subject COLLATE RTRIM, normalized_subject COLLATE RTRIM);
  CREATE INDEX subject_subject_index ON subjects(subject);
  CREATE INDEX subject_normalized_subject_index ON subjects(normalized_subject);
  CREATE TABLE addresses (ROWID INTEGER PRIMARY KEY, address COLLATE NOCASE, comment, UNIQUE(address, comment));
  CREATE INDEX addresses_address_index ON addresses(address);
  CREATE TABLE mailboxes (ROWID INTEGER PRIMARY KEY, url UNIQUE, total_count INTEGER DEFAULT 0, unread_count INTEGER DEFAULT 0, unseen_count INTEGER DEFAULT 0, deleted_count INTEGER DEFAULT 0, unread_count_adjusted_for_duplicates INTEGER DEFAULT 0, change_identifier, source INTEGER, alleged_change_identifier);
  CREATE INDEX mailboxes_source_index ON mailboxes(source);
  CREATE TABLE labels (ROWID INTEGER PRIMARY KEY, message_id INTEGER NOT NULL, mailbox_id INTEGER NOT NULL, UNIQUE(message_id, mailbox_id));
  CREATE INDEX labels_message_id_mailbox_id_index ON labels(message_id, mailbox_id);
  CREATE INDEX labels_mailbox_id_index ON labels(mailbox_id);
  
  explain query plan
  SELECT messages.ROWID,
         messages.message_id,
         messages.remote_id,
         messages.date_received,
         messages.date_sent,
         messages.flags,
         messages.size,
         messages.color,
         messages.date_last_viewed,
         messages.subject_prefix,
         subjects.subject,
         sender.comment,
         sender.address,
         NULL,
         messages.mailbox,
         messages.original_mailbox,
         NULL,
         NULL,
         messages.type,
         messages.document_id,
         sender,
         NULL,
         messages.conversation_id,
         messages.conversation_position,
         agglabels.labels
   FROM mailboxes AS mailbox
        JOIN messages ON mailbox.ROWID = messages.mailbox
        LEFT OUTER JOIN subjects ON messages.subject = subjects.ROWID
        LEFT OUTER JOIN addresses AS sender ON messages.sender = sender.ROWID
        LEFT OUTER JOIN (
               SELECT message_id, group_concat(mailbox_id) as labels
               FROM labels GROUP BY message_id
             ) AS agglabels ON messages.ROWID = agglabels.message_id
  WHERE (mailbox.url = 'imap://email.app@imap.gmail.com/%5BGmail%5D/All%20Mail')
    AND (messages.ROWID IN (
            SELECT labels.message_id
              FROM labels JOIN mailboxes ON labels.mailbox_id = mailboxes.ROWID
             WHERE mailboxes.url = 'imap://email.app@imap.gmail.com/INBOX'))
    AND messages.mailbox in (6,12,18,24,30,36,42,1,7,13,19,25,31,37,43,2,8,
                             14,20,26,32,38,3,9,15,21,27,33,39,4,10,16,22,28,
                             34,40,5,11,17,23,35,41)
   ORDER BY date_received DESC;
} {/agglabels USING AUTOMATIC COVERING INDEX/}

# A test case for VIEWs
#
do_execsql_test autoindex1-901 {
  CREATE TABLE t1(x INTEGER PRIMARY KEY, y, z);
  CREATE TABLE t2(a, b);
  CREATE VIEW agg2 AS SELECT a, sum(b) AS m FROM t2 GROUP BY a;
  EXPLAIN QUERY PLAN
  SELECT t1.z, agg2.m
    FROM t1 JOIN agg2 ON t1.y=agg2.m
   WHERE t1.x IN (1,2,3);
} {/USING AUTOMATIC COVERING INDEX/}


finish_test

  catchsql { SELECT * FROM r WHERE x >= 10.0 }
} {1 {database disk image is malformed}}

do_test 2.2 {
  catchsql { SELECT * FROM r WHERE x >= 10 }
} {1 {database disk image is malformed}}




reset_db

do_execsql_test 3.1 {

  PRAGMA page_size = 512;
  CREATE TABLE t1(a INTEGER PRIMARY KEY, b);
  WITH s(a, b) AS (
    SELECT 2, 'abcdefghij'
    UNION ALL
    SELECT a+2, b FROM s WHERe a < 40
  )
  INSERT INTO t1 SELECT * FROM s;
} {}

do_test 3.2 {
  hexio_write test.db [expr 512+3] 0054
  db close
  sqlite3 db test.db
  execsql { INSERT INTO t1 VALUES(5, 'klmnopqrst') }
  execsql { INSERT INTO t1 VALUES(7, 'klmnopqrst') }
} {}

db close
sqlite3 db test.db
do_catchsql_test 3.2 {
  INSERT INTO t1 VALUES(9, 'klmnopqrst');
} {1 {database disk image is malformed}}


finish_test

  catchsql { SELECT * FROM r WHERE x >= 10.0 }
} {1 {database disk image is malformed}}

do_test 2.2 {
  catchsql { SELECT * FROM r WHERE x >= 10 }
} {1 {database disk image is malformed}}

if {[db one {SELECT sqlite_compileoption_used('ENABLE_OVERSIZE_CELL_CHECK')}]} {
  # The following tests only work if OVERSIZE_CELL_CHECK is disabled
} else {
  reset_db

  do_execsql_test 3.1 {
     PRAGMA auto_vacuum=0;
     PRAGMA page_size = 512;
     CREATE TABLE t1(a INTEGER PRIMARY KEY, b);
     WITH s(a, b) AS (
       SELECT 2, 'abcdefghij'
       UNION ALL
       SELECT a+2, b FROM s WHERe a < 40
     )
     INSERT INTO t1 SELECT * FROM s;
   } {}
   
   do_test 3.2 {
     hexio_write test.db [expr 512+3] 0054
     db close
     sqlite3 db test.db
     execsql { INSERT INTO t1 VALUES(5, 'klmnopqrst') }
     execsql { INSERT INTO t1 VALUES(7, 'klmnopqrst') }
   } {}
   
   db close
   sqlite3 db test.db
   do_catchsql_test 3.3 {
     INSERT INTO t1 VALUES(9, 'klmnopqrst');
   } {1 {database disk image is malformed}}

} ;# end-if !defined(ENABLE_OVERSIZE_CELL_CHECK)
finish_test

    f INT DEFAULT -9223372036854775808,
    g INT DEFAULT (-(-9223372036854775808)),
    h INT DEFAULT (-(-9223372036854775807))
  );
  INSERT INTO t300 DEFAULT VALUES;
  SELECT * FROM t300;
} {2147483647 2147483648 9223372036854775807 -2147483647 -2147483648 -9223372036854775808 9.22337203685478e+18 9223372036854775807}





























finish_test

    f INT DEFAULT -9223372036854775808,
    g INT DEFAULT (-(-9223372036854775808)),
    h INT DEFAULT (-(-9223372036854775807))
  );
  INSERT INTO t300 DEFAULT VALUES;
  SELECT * FROM t300;
} {2147483647 2147483648 9223372036854775807 -2147483647 -2147483648 -9223372036854775808 9.22337203685478e+18 9223372036854775807}

# Do now allow bound parameters in new DEFAULT values. 
# Silently convert bound parameters to NULL in DEFAULT causes
# in the sqlite_master table, for backwards compatibility.
#
db close
forcedelete test.db
sqlite3 db test.db
do_execsql_test default-4.0 {
  CREATE TABLE t1(a TEXT, b TEXT DEFAULT(99));
  PRAGMA writable_schema=ON;
  UPDATE sqlite_master SET sql='CREATE TABLE t1(a TEXT, b TEXT DEFAULT(:xyz))';
} {}
db close 
sqlite3 db test.db
do_execsql_test default-4.1 {
  INSERT INTO t1(a) VALUES('xyzzy');
  SELECT a, quote(b) FROM t1;
} {xyzzy NULL}
do_catchsql_test default-4.2 {
  CREATE TABLE t2(a TEXT, b TEXT DEFAULT(:xyz));
} {1 {default value of column [b] is not constant}}
do_catchsql_test default-4.3 {
  CREATE TABLE t2(a TEXT, b TEXT DEFAULT(abs(:xyz)));
} {1 {default value of column [b] is not constant}}
do_catchsql_test default-4.4 {
  CREATE TABLE t2(a TEXT, b TEXT DEFAULT(98+coalesce(5,:xyz)));
} {1 {default value of column [b] is not constant}}

finish_test

  execsql { DELETE FROM t1 }
} {
  1   "INSERT INTO t1(x, y) VALUES('abc', 'xyz')"   {'abc' 'xyz' NULL}
  2   "INSERT INTO t1(x, z) VALUES('abc', 'xyz')"   {'abc' NULL 'xyz'}
  3   "INSERT INTO t1 DEFAULT VALUES"               {NULL NULL NULL}
}

# EVIDENCE-OF: R-62940-43005 An explicit DEFAULT clause may specify that
# the default value is NULL, a string constant, a blob constant, a
# signed-number, or any constant expression enclosed in parentheses. An
# explicit default value may also be one of the special case-independent
# keywords CURRENT_TIME, CURRENT_DATE or CURRENT_TIMESTAMP.
#
do_execsql_test e_createtable-3.3.1 {
  CREATE TABLE t4(
    a DEFAULT NULL,
    b DEFAULT 'string constant',
    c DEFAULT X'424C4F42',
    d DEFAULT 1,
................................................................................
    h DEFAULT ( substr('abcd', 0, 2) || 'cd' ),
    i DEFAULT CURRENT_TIME,
    j DEFAULT CURRENT_DATE,
    k DEFAULT CURRENT_TIMESTAMP
  );
} {}

# EVIDENCE-OF: R-36381-62919 For the purposes of the DEFAULT clause, an
# expression is considered constant provided that it does not contain
# any sub-queries, column or table references, or string literals
# enclosed in double-quotes instead of single-quotes.
#
do_createtable_tests 3.4.1 -error {
  default value of column [x] is not constant
} {
  1   {CREATE TABLE t5(x DEFAULT ( (SELECT 1) ))}  {}
  2   {CREATE TABLE t5(x DEFAULT ( "abc" ))}  {}
  3   {CREATE TABLE t5(x DEFAULT ( 1 IN (SELECT 1) ))}  {}
  4   {CREATE TABLE t5(x DEFAULT ( EXISTS (SELECT 1) ))}  {}

}
do_createtable_tests 3.4.2 -repair {
  catchsql { DROP TABLE t5 }
} {
  1   {CREATE TABLE t5(x DEFAULT ( 'abc' ))}  {}
  2   {CREATE TABLE t5(x DEFAULT ( 1 IN (1, 2, 3) ))}  {}
}

  execsql { DELETE FROM t1 }
} {
  1   "INSERT INTO t1(x, y) VALUES('abc', 'xyz')"   {'abc' 'xyz' NULL}
  2   "INSERT INTO t1(x, z) VALUES('abc', 'xyz')"   {'abc' NULL 'xyz'}
  3   "INSERT INTO t1 DEFAULT VALUES"               {NULL NULL NULL}
}

# EVIDENCE-OF: R-07343-35026 An explicit DEFAULT clause may specify that
# the default value is NULL, a string constant, a blob constant, a
# signed-number, or any constant expression enclosed in parentheses. A
# default value may also be one of the special case-independent keywords
# CURRENT_TIME, CURRENT_DATE or CURRENT_TIMESTAMP.
#
do_execsql_test e_createtable-3.3.1 {
  CREATE TABLE t4(
    a DEFAULT NULL,
    b DEFAULT 'string constant',
    c DEFAULT X'424C4F42',
    d DEFAULT 1,
................................................................................
    h DEFAULT ( substr('abcd', 0, 2) || 'cd' ),
    i DEFAULT CURRENT_TIME,
    j DEFAULT CURRENT_DATE,
    k DEFAULT CURRENT_TIMESTAMP
  );
} {}

# EVIDENCE-OF: R-18415-27776 For the purposes of the DEFAULT clause, an
# expression is considered constant if it does contains no sub-queries,
# column or table references, bound parameters, or string literals
# enclosed in double-quotes instead of single-quotes.
#
do_createtable_tests 3.4.1 -error {
  default value of column [x] is not constant
} {
  1   {CREATE TABLE t5(x DEFAULT ( (SELECT 1) ))}  {}
  2   {CREATE TABLE t5(x DEFAULT ( "abc" ))}  {}
  3   {CREATE TABLE t5(x DEFAULT ( 1 IN (SELECT 1) ))}  {}
  4   {CREATE TABLE t5(x DEFAULT ( EXISTS (SELECT 1) ))}  {}
  5   {CREATE TABLE t5(x DEFAULT ( x!=?1 ))}  {}
}
do_createtable_tests 3.4.2 -repair {
  catchsql { DROP TABLE t5 }
} {
  1   {CREATE TABLE t5(x DEFAULT ( 'abc' ))}  {}
  2   {CREATE TABLE t5(x DEFAULT ( 1 IN (1, 2, 3) ))}  {}
}

  sqlite3_close $DB
}

# ensure uri processing enabled for the rest of the tests
sqlite3_shutdown
sqlite3_config_uri 1




# EVIDENCE-OF: R-17482-00398 If the authority is not an empty string or
# "localhost", an error is returned to the caller.
#
if {$tcl_platform(platform) == "unix"} {
  set flags [list SQLITE_OPEN_READWRITE SQLITE_OPEN_CREATE SQLITE_OPEN_URI]
  foreach {tn uri error} "
    1  {file://localhost[test_pwd /]test.db}   {not an error}

  sqlite3_close $DB
}

# ensure uri processing enabled for the rest of the tests
sqlite3_shutdown
sqlite3_config_uri 1

# EVIDENCE-OF: R-06842-00595 If the URI contains an authority, then it
# must be either an empty string or the string "localhost".
#
# EVIDENCE-OF: R-17482-00398 If the authority is not an empty string or
# "localhost", an error is returned to the caller.
#
if {$tcl_platform(platform) == "unix"} {
  set flags [list SQLITE_OPEN_READWRITE SQLITE_OPEN_CREATE SQLITE_OPEN_URI]
  foreach {tn uri error} "
    1  {file://localhost[test_pwd /]test.db}   {not an error}

  execsql {
    CREATE TABLE t2(x,y);
    INSERT INTO t2 SELECT x, x+1 FROM t1 WHERE x<5;
    SELECT x, test_eval('DELETE FROM t2 WHERE x='||x), y FROM t2;
  }
} {1 {} {} 2 {} {} 3 {} {} 4 {} {}}
do_test eval-2.2 {












  execsql {
    SELECT * FROM t2
  }
} {}

# Modify a row while it is being read.
#

  execsql {
    CREATE TABLE t2(x,y);
    INSERT INTO t2 SELECT x, x+1 FROM t1 WHERE x<5;
    SELECT x, test_eval('DELETE FROM t2 WHERE x='||x), y FROM t2;
  }
} {1 {} {} 2 {} {} 3 {} {} 4 {} {}}
do_test eval-2.2 {
  execsql {
    SELECT * FROM t2
  }
} {}
do_test eval-2.3 {
  execsql {
    INSERT INTO t2 SELECT x, x+1 FROM t1 WHERE x<5;
    SELECT x, test_eval('DELETE FROM t2 WHERE x='||x), y FROM t2
     ORDER BY rowid DESC;
  }
} {4 {} {} 3 {} {} 2 {} {} 1 {} {}}
do_test eval-2.4 {
  execsql {
    SELECT * FROM t2
  }
} {}

# Modify a row while it is being read.
#

test_expr expr-1.124 {i1=NULL, i2=NULL} \
  {CASE WHEN i1 IS NOT i2 THEN 'yes' ELSE 'no' END} no
test_expr expr-1.125 {i1=6, i2=NULL} \
  {CASE WHEN i1 IS NOT i2 THEN 'yes' ELSE 'no' END} yes
test_expr expr-1.126 {i1=8, i2=8} \
  {CASE WHEN i1 IS NOT i2 THEN 'yes' ELSE 'no' END} no





ifcapable floatingpoint {if {[working_64bit_int]} {
  test_expr expr-1.200\
      {i1=9223372036854775806, i2=1} {i1+i2}      9223372036854775807
  test_realnum_expr expr-1.201\
      {i1=9223372036854775806, i2=2} {i1+i2}      9.22337203685478e+18
  test_realnum_expr expr-1.202\
      {i1=9223372036854775806, i2=100000} {i1+i2} 9.22337203685488e+18

test_expr expr-1.124 {i1=NULL, i2=NULL} \
  {CASE WHEN i1 IS NOT i2 THEN 'yes' ELSE 'no' END} no
test_expr expr-1.125 {i1=6, i2=NULL} \
  {CASE WHEN i1 IS NOT i2 THEN 'yes' ELSE 'no' END} yes
test_expr expr-1.126 {i1=8, i2=8} \
  {CASE WHEN i1 IS NOT i2 THEN 'yes' ELSE 'no' END} no

do_catchsql_test expr-1.127 {
  SELECT 1 IS #1;
} {1 {near "#1": syntax error}}

ifcapable floatingpoint {if {[working_64bit_int]} {
  test_expr expr-1.200\
      {i1=9223372036854775806, i2=1} {i1+i2}      9223372036854775807
  test_realnum_expr expr-1.201\
      {i1=9223372036854775806, i2=2} {i1+i2}      9.22337203685478e+18
  test_realnum_expr expr-1.202\
      {i1=9223372036854775806, i2=100000} {i1+i2} 9.22337203685488e+18

ifcapable !fts3||!icu {
  finish_test
  return
}

set sqlite_fts3_enable_parentheses 1

proc test_icu_fts3expr {expr} {
  db one {SELECT fts3_exprtest('icu', $expr, 'a', 'b', 'c')}
}

proc do_icu_expr_test {tn expr res} {
  uplevel [list do_test $tn [list test_icu_fts3expr $expr] $res]




}

#-------------------------------------------------------------------------
#
do_icu_expr_test 1.1 "abcd"    {PHRASE 3 0 abcd}
do_icu_expr_test 1.2 " tag "   {PHRASE 3 0 tag}
do_icu_expr_test 1.3 {"x y z"} {PHRASE 3 0 x y z}
................................................................................
do_icu_expr_test 1.8 {d:word} {PHRASE 3 0 d:word}

set sqlite_fts3_enable_parentheses 0

do_icu_expr_test 2.1 {
  f (e NEAR/2 a)
} {AND {AND {AND {PHRASE 3 0 f} {PHRASE 3 0 (}} {NEAR/2 {PHRASE 3 0 e} {PHRASE 3 0 a}}} {PHRASE 3 0 )}}






















finish_test

ifcapable !fts3||!icu {
  finish_test
  return
}

set sqlite_fts3_enable_parentheses 1

proc test_fts3expr {tokenizer expr} {
  db one {SELECT fts3_exprtest($tokenizer, $expr, 'a', 'b', 'c')}
}

proc do_icu_expr_test {tn expr res} {
  uplevel [list do_test $tn [list test_fts3expr icu $expr] [list {*}$res]]
}

proc do_simple_expr_test {tn expr res} {
  uplevel [list do_test $tn [list test_fts3expr simple $expr] [list {*}$res]]
}

#-------------------------------------------------------------------------
#
do_icu_expr_test 1.1 "abcd"    {PHRASE 3 0 abcd}
do_icu_expr_test 1.2 " tag "   {PHRASE 3 0 tag}
do_icu_expr_test 1.3 {"x y z"} {PHRASE 3 0 x y z}
................................................................................
do_icu_expr_test 1.8 {d:word} {PHRASE 3 0 d:word}

set sqlite_fts3_enable_parentheses 0

do_icu_expr_test 2.1 {
  f (e NEAR/2 a)
} {AND {AND {AND {PHRASE 3 0 f} {PHRASE 3 0 (}} {NEAR/2 {PHRASE 3 0 e} {PHRASE 3 0 a}}} {PHRASE 3 0 )}}

#-------------------------------------------------------------------------
#
do_simple_expr_test 3.1 {*lOl* *h4h*} {
  AND {PHRASE 3 0 lol+} {PHRASE 3 0 h4h+}
}

do_icu_expr_test 3.2 {*lOl* *h4h*} {
  AND {AND {AND {PHRASE 3 0 *} {PHRASE 3 0 lol+}} {PHRASE 3 0 *}} {PHRASE 3 0 h4h+}
}

do_simple_expr_test 3.3 { * }    { }
do_simple_expr_test 3.4 { *a }   { PHRASE 3 0 a }
do_simple_expr_test 3.5 { a*b }  { AND {PHRASE 3 0 a+} {PHRASE 3 0 b} }
do_simple_expr_test 3.6 { *a*b } { AND {PHRASE 3 0 a+} {PHRASE 3 0 b} }
do_simple_expr_test 3.7 { *"abc" } { PHRASE 3 0 abc }
do_simple_expr_test 3.8 { "abc"* } { PHRASE 3 0 abc }
do_simple_expr_test 3.8 { "ab*c" } { PHRASE 3 0 ab+ c }

do_icu_expr_test    3.9 { "ab*c" } { PHRASE 3 0 ab+ * c }
do_icu_expr_test    3.10 { ab*c } { AND {PHRASE 3 0 ab+} {PHRASE 3 0 c}}

finish_test

do_execsql_test 9.1 {
  CREATE VIRTUAL TABLE ft2 USING fts4;
  INSERT INTO ft2 VALUES('a b c d e');
  INSERT INTO ft2 VALUES('f a b c d');
  SELECT snippet(ft2, '[', ']', '', -1, 1) FROM ft2 WHERE ft2 MATCH 'c';
} {{[c]} {[c]}}


















finish_test

do_execsql_test 9.1 {
  CREATE VIRTUAL TABLE ft2 USING fts4;
  INSERT INTO ft2 VALUES('a b c d e');
  INSERT INTO ft2 VALUES('f a b c d');
  SELECT snippet(ft2, '[', ']', '', -1, 1) FROM ft2 WHERE ft2 MATCH 'c';
} {{[c]} {[c]}}

#---------------------------------------------------------------------------
# Test for a memory leak
#
do_execsql_test 10.1 {
  DROP TABLE t10;
  CREATE VIRTUAL TABLE t10 USING fts4(idx, value);
  INSERT INTO t10 values (1, 'one'),(2, 'two'),(3, 'three');
  SELECT docId, t10.*
    FROM t10
    JOIN (SELECT 1 AS idx UNION SELECT 2 UNION SELECT 3) AS x
   WHERE t10 MATCH x.idx
     AND matchinfo(t10) not null
   GROUP BY docId
   ORDER BY 1;
} {1 1 one 2 2 two 3 3 three}
  

finish_test

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set ::testprefix index5

do_test 1.1 {



  execsql {
    PRAGMA page_size = 1024;
    CREATE TABLE t1(x);
    BEGIN;
  }
  for {set i 0} {$i < 100000} {incr i} {
    execsql { INSERT INTO t1 VALUES(randstr(100,100)) }
................................................................................

db close
testvfs tvfs
tvfs filter xWrite
tvfs script write_cb
proc write_cb {xCall file handle iOfst args} {
  if {[file tail $file]=="test.db"} {
    lappend ::write_list [expr $iOfst/1024]
  }
}

do_test 1.2 {
  sqlite3 db test.db -vfs tvfs
  set ::write_list [list]
  execsql { CREATE INDEX i1 ON t1(x) }

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set ::testprefix index5

do_test 1.1 {
  if {[permutation]=="memsubsys1"} {
    execsql { PRAGMA auto_vacuum = 0; }
  }
  execsql {
    PRAGMA page_size = 1024;
    CREATE TABLE t1(x);
    BEGIN;
  }
  for {set i 0} {$i < 100000} {incr i} {
    execsql { INSERT INTO t1 VALUES(randstr(100,100)) }
................................................................................

db close
testvfs tvfs
tvfs filter xWrite
tvfs script write_cb
proc write_cb {xCall file handle iOfst args} {
  if {[file tail $file]=="test.db"} {
    lappend ::write_list [expr $iOfst/1024 + 1]
  }
}

do_test 1.2 {
  sqlite3 db test.db -vfs tvfs
  set ::write_list [list]
  execsql { CREATE INDEX i1 ON t1(x) }

} {}

#####################################################################

do_test lock5-none.1 {
  sqlite3 db test.db -vfs unix-none
  sqlite3 db2 test.db -vfs unix-none

  execsql {
    BEGIN;
    INSERT INTO t1 VALUES(3, 4);
  }
} {}
do_test lock5-none.2 {
  execsql { SELECT * FROM t1 }
} {1 2 3 4}
do_test lock5-flock.3 {
  execsql { SELECT * FROM t1 } db2
} {1 2}
do_test lock5-none.4 {
  execsql { 
    BEGIN;
    SELECT * FROM t1;
  } db2
} {1 2}
................................................................................
ifcapable memorymanage {
  do_test lock5-none.6 {
    sqlite3_release_memory 1000000
    execsql {SELECT * FROM t1} db2
  } {1 2 3 4}
}

do_test lock5-flock.X {
  db close
  db2 close
} {}

ifcapable lock_proxy_pragmas {
  set env(SQLITE_FORCE_PROXY_LOCKING) $::using_proxy
}

finish_test

} {}

#####################################################################

do_test lock5-none.1 {
  sqlite3 db test.db -vfs unix-none
  sqlite3 db2 test.db -vfs unix-none
  execsql { PRAGMA mmap_size = 0 } db2
  execsql {
    BEGIN;
    INSERT INTO t1 VALUES(3, 4);
  }
} {}
do_test lock5-none.2 {
  execsql { SELECT * FROM t1 }
} {1 2 3 4}
do_test lock5-none.3 {
  execsql { SELECT * FROM t1; } db2
} {1 2}
do_test lock5-none.4 {
  execsql { 
    BEGIN;
    SELECT * FROM t1;
  } db2
} {1 2}
................................................................................
ifcapable memorymanage {
  do_test lock5-none.6 {
    sqlite3_release_memory 1000000
    execsql {SELECT * FROM t1} db2
  } {1 2 3 4}
}

do_test lock5-none.X {
  db close
  db2 close
} {}

ifcapable lock_proxy_pragmas {
  set env(SQLITE_FORCE_PROXY_LOCKING) $::using_proxy
}

finish_test

  }
}

do_execsql_test 7.0 {
  PRAGMA cache_size = 5;
}
do_faultsim_test 7 -faults oom-trans* -prep {
  if {$iFail < 500} { set iFail 2000 }
  if {$iFail > 1215} { set iFail 2000 }
} -body {
  execsql {
    WITH r(x,y) AS (
      SELECT 1, randomblob(100)
      UNION ALL
      SELECT x+1, randomblob(100) FROM r
      LIMIT 1000

  }
}

do_execsql_test 7.0 {
  PRAGMA cache_size = 5;
}
do_faultsim_test 7 -faults oom-trans* -prep {


} -body {
  execsql {
    WITH r(x,y) AS (
      SELECT 1, randomblob(100)
      UNION ALL
      SELECT x+1, randomblob(100) FROM r
      LIMIT 1000

# 2014-09-25
#
# 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 tests for the "truncate" option in the multiplexor.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set ::testprefix multiplex4

db close
sqlite3_shutdown
sqlite3_multiplex_initialize {} 0

# delete all filesl with the base name of $basename
#
proc multiplex_delete_db {basename} {
  foreach file [glob -nocomplain $basename.*] {
    forcedelete $file
  }
}

# Return a sorted list of all files with the base name of $basename.
# Except, delete all text from the end of $basename through the NNN
# suffix on the end of the filename.
#
proc multiplex_file_list {basename} {
  set x {}
  foreach file [glob -nocomplain $basename.*] {
    regsub "^$basename\\..*(\\d\\d\\d)\$" $file $basename.\\1 file
    lappend x $file
  }
  return [lsort $x]
}

do_test multiplex4-1.0 {
  multiplex_delete_db mx4test
  sqlite3 db {file:mx4test.db?chunksize=10&truncate=1} -uri 1 -vfs multiplex
  db eval {
    CREATE TABLE t1(x);
    INSERT INTO t1(x) VALUES(randomblob(250000));
  }
  multiplex_file_list mx4test
} {mx4test.001 mx4test.db}

do_test multiplex4-1.1 {
  db eval {
    DELETE FROM t1;
    VACUUM;
  }
  multiplex_file_list mx4test
} {mx4test.db}

do_test multiplex4-1.2 {
  db eval {PRAGMA multiplex_truncate}
} {on}
do_test multiplex4-1.3 {
  db eval {PRAGMA multiplex_truncate=off}
} {off}
do_test multiplex4-1.4 {
  db eval {PRAGMA multiplex_truncate}
} {off}
do_test multiplex4-1.5 {
  db eval {PRAGMA multiplex_truncate=on}
} {on}
do_test multiplex4-1.6 {
  db eval {PRAGMA multiplex_truncate}
} {on}
do_test multiplex4-1.7 {
  db eval {PRAGMA multiplex_truncate=0}
} {off}
do_test multiplex4-1.8 {
  db eval {PRAGMA multiplex_truncate=1}
} {on}
do_test multiplex4-1.9 {
  db eval {PRAGMA multiplex_truncate=0}
} {off}

do_test multiplex4-1.10 {
  db eval {
    INSERT INTO t1(x) VALUES(randomblob(250000));
  }
  multiplex_file_list mx4test
} {mx4test.001 mx4test.db}

do_test multiplex4-1.11 {
  db eval {
    DELETE FROM t1;
    VACUUM;
  }
  multiplex_file_list mx4test
} {mx4test.001 mx4test.db}

do_test multiplex4-1.12 {
  db eval {
    PRAGMA multiplex_truncate=ON;
    DROP TABLE t1;
    VACUUM;
  }
  multiplex_file_list mx4test
} {mx4test.db}

catch { db close }
forcedelete mx4test.db
sqlite3_multiplex_shutdown
finish_test

  SELECT (
    SELECT 'hardware' FROM ( 
      SELECT 'software' ORDER BY 'firmware' ASC, 'sportswear' DESC 
    ) GROUP BY 1 HAVING length(b)
  )
  FROM abc;
} {hardware hardware hardware}
















finish_test

  SELECT (
    SELECT 'hardware' FROM ( 
      SELECT 'software' ORDER BY 'firmware' ASC, 'sportswear' DESC 
    ) GROUP BY 1 HAVING length(b)
  )
  FROM abc;
} {hardware hardware hardware}

# Here is a test for a query-planner problem reported on the SQLite
# mailing list on 2014-09-18 by "Merike".  Beginning with version 3.8.0,
# a separate sort was being used rather than using the single-column
# index.  This was due to an oversight in the indexMightHelpWithOrderby()
# routine in where.c.
#
do_execsql_test 7.0 {
  CREATE TABLE t7(a,b);
  CREATE INDEX t7a ON t7(a);
  CREATE INDEX t7ab ON t7(a,b);
  EXPLAIN QUERY PLAN
  SELECT * FROM t7 WHERE a=?1 ORDER BY rowid;
} {~/ORDER BY/}


finish_test

# 2014 October 01
#
# 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 implements regression tests for SQLite library.  The
# focus of this file is testing the SQLITE_DIRECT_OVERFLOW_READ logic.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix ovfl

# Populate table t2:
#
#   CREATE TABLE t1(c1 TEXT, c2 TEXT);
#
# with 2000 rows. In each row, c2 spans multiple overflow pages. The text
# value of c1 ranges in size from 1 to 2000 bytes. The idea is to create
# at least one row where the first byte of c2 is also the first byte of
# an overflow page. This was at one point exposing an obscure bug in the
# SQLITE_DIRECT_OVERFLOW_READ logic.
#
do_test 1.1 {
  set c2 [string repeat abcdefghij 200]
  execsql {
    PRAGMA cache_size = 10;
    CREATE TABLE t1(c1 TEXT, c2 TEXT);
    BEGIN;
  }
  for {set i 1} {$i <= 2000} {incr i} {
    set c1 [string repeat . $i]
    execsql { INSERT INTO t1 VALUES($c1, $c2) }
  }
  execsql COMMIT
} {}

do_execsql_test 1.2 {
  SELECT sum(length(c2)) FROM t1;
} [expr 2000 * 2000]

finish_test

This Tcl script is used to test the various configurations required
before releasing a new version. Supported command line options (all 
optional) are:

    -makefile PATH-TO-MAKEFILE           (default "releasetest.mk")
    -platform PLATFORM                   (see below)
    -quick    BOOLEAN                    (default "0")


The default value for -makefile is "./releasetest.mk".

The script determines the default value for -platform using the
$tcl_platform(os) and $tcl_platform(machine) variables. Supported 
platforms are "Linux-x86", "Linux-x86_64" and "Darwin-i386".

................................................................................
    "Secure-Delete"           test
    "Unlock-Notify"           "QUICKTEST_INCLUDE=notify2.test test"
    "Update-Delete-Limit"     test
    "Extra-Robustness"        test
    "Device-Two"              test
    "Ftrapv"                  test
    "No-lookaside"            test

    "Default"                 "threadtest test"
    "Device-One"              fulltest
  }
  Linux-i686 {
    "Devkit"                  test
    "Unlock-Notify"           "QUICKTEST_INCLUDE=notify2.test test"
    "Device-One"              test
    "Device-Two"              test
................................................................................
# Currently the only option supported is "-makefile", default
# "releasetest.mk". Set the ::MAKEFILE variable to the value of this
# option.
#
proc process_options {argv} {
  set ::MAKEFILE releasetest.mk                       ;# Default value
  set ::QUICK    0                                    ;# Default value

  set platform $::tcl_platform(os)-$::tcl_platform(machine)

  for {set i 0} {$i < [llength $argv]} {incr i} {
    switch -- [lindex $argv $i] {
      -makefile {
        incr i
        set ::MAKEFILE [lindex $argv $i]
................................................................................
        set platform [lindex $argv $i]
      }

      -quick {
        incr i
        set ::QUICK [lindex $argv $i]
      }





  
      default {
        puts stderr ""
        puts stderr [string trim $::USAGE_MESSAGE]
        exit -1
      }
    }
................................................................................
      lappend print "\"$p\""
    }
    lset print end "or [lindex $print end]"
    puts "[join $print {, }]."
    exit
  }





  set ::CONFIGLIST $::Platforms($platform)

  puts "Running the following configurations for $platform:"
  puts "    [string trim $::CONFIGLIST]"
}

# Main routine.
#
proc main {argv} {

This Tcl script is used to test the various configurations required
before releasing a new version. Supported command line options (all 
optional) are:

    -makefile PATH-TO-MAKEFILE           (default "releasetest.mk")
    -platform PLATFORM                   (see below)
    -quick    BOOLEAN                    (default "0")
    -config   CONFIGNAME                 (Run only CONFIGNAME)

The default value for -makefile is "./releasetest.mk".

The script determines the default value for -platform using the
$tcl_platform(os) and $tcl_platform(machine) variables. Supported 
platforms are "Linux-x86", "Linux-x86_64" and "Darwin-i386".

................................................................................
    "Secure-Delete"           test
    "Unlock-Notify"           "QUICKTEST_INCLUDE=notify2.test test"
    "Update-Delete-Limit"     test
    "Extra-Robustness"        test
    "Device-Two"              test
    "Ftrapv"                  test
    "No-lookaside"            test
    "Devkit"                  test
    "Default"                 "threadtest fulltest"
    "Device-One"              fulltest
  }
  Linux-i686 {
    "Devkit"                  test
    "Unlock-Notify"           "QUICKTEST_INCLUDE=notify2.test test"
    "Device-One"              test
    "Device-Two"              test
................................................................................
# Currently the only option supported is "-makefile", default
# "releasetest.mk". Set the ::MAKEFILE variable to the value of this
# option.
#
proc process_options {argv} {
  set ::MAKEFILE releasetest.mk                       ;# Default value
  set ::QUICK    0                                    ;# Default value
  set config {}
  set platform $::tcl_platform(os)-$::tcl_platform(machine)

  for {set i 0} {$i < [llength $argv]} {incr i} {
    switch -- [lindex $argv $i] {
      -makefile {
        incr i
        set ::MAKEFILE [lindex $argv $i]
................................................................................
        set platform [lindex $argv $i]
      }

      -quick {
        incr i
        set ::QUICK [lindex $argv $i]
      }

      -config {
        incr i
        set config [lindex $argv $i]
      }
  
      default {
        puts stderr ""
        puts stderr [string trim $::USAGE_MESSAGE]
        exit -1
      }
    }
................................................................................
      lappend print "\"$p\""
    }
    lset print end "or [lindex $print end]"
    puts "[join $print {, }]."
    exit
  }

  if {$config!=""} {
    if {[llength $config]==1} {lappend config fulltest}
    set ::CONFIGLIST $config
  } else {
    set ::CONFIGLIST $::Platforms($platform)
  }
  puts "Running the following configurations for $platform:"
  puts "    [string trim $::CONFIGLIST]"
}

# Main routine.
#
proc main {argv} {

} {a}
do_test rowid-12.2 {
  db close
  sqlite3 db test.db
  save_prng_state
  execsql {
    INSERT INTO t7 VALUES(NULL,'b');
    SELECT x, y FROM t7;
  }
} {1 b 9223372036854775807 a}
execsql {INSERT INTO t7 VALUES(2,'y');}
for {set i 1} {$i<100} {incr i} {
  do_test rowid-12.3.$i {
    db eval {DELETE FROM t7temp; INSERT INTO t7temp VALUES(1);}
    restore_prng_state
    execsql {
      INSERT INTO t7 VALUES(NULL,'x');
................................................................................
  db eval {DELETE FROM t7temp; INSERT INTO t7temp VALUES(1);}
  restore_prng_state
  catchsql {
    INSERT INTO t7 VALUES(NULL,'x');
  }
} {1 {database or disk is full}}
















finish_test

} {a}
do_test rowid-12.2 {
  db close
  sqlite3 db test.db
  save_prng_state
  execsql {
    INSERT INTO t7 VALUES(NULL,'b');
    SELECT x, y FROM t7 ORDER BY x;
  }
} {/\d+ b 9223372036854775807 a/}
execsql {INSERT INTO t7 VALUES(2,'y');}
for {set i 1} {$i<100} {incr i} {
  do_test rowid-12.3.$i {
    db eval {DELETE FROM t7temp; INSERT INTO t7temp VALUES(1);}
    restore_prng_state
    execsql {
      INSERT INTO t7 VALUES(NULL,'x');
................................................................................
  db eval {DELETE FROM t7temp; INSERT INTO t7temp VALUES(1);}
  restore_prng_state
  catchsql {
    INSERT INTO t7 VALUES(NULL,'x');
  }
} {1 {database or disk is full}}

# INSERTs that happen inside of nested function calls are recorded
# by last_insert_rowid.
#
proc rowid_addrow_func {n} {
  db eval {INSERT INTO t13(rowid,x) VALUES($n,$n*$n)}
  return [db last_insert_rowid]
}
db function addrow rowid_addrow_func
do_execsql_test rowid-13.1 {
  CREATE TABLE t13(x);
  INSERT INTO t13(rowid,x) VALUES(1234,5);
  SELECT rowid, x, addrow(rowid+1000), '|' FROM t13 LIMIT 3;
  SELECT last_insert_rowid();
} {1234 5 2234 | 2234 4990756 3234 | 3234 10458756 4234 | 4234}

finish_test

} {}
db cache flush
do_execsql_test skipscan1-5.3 {
  EXPLAIN QUERY PLAN
    SELECT xh, loc FROM t5 WHERE loc >= 'M' AND loc < 'N';
} {/.*COVERING INDEX t5i1 .*/}





























finish_test

} {}
db cache flush
do_execsql_test skipscan1-5.3 {
  EXPLAIN QUERY PLAN
    SELECT xh, loc FROM t5 WHERE loc >= 'M' AND loc < 'N';
} {/.*COVERING INDEX t5i1 .*/}

# The column used by the skip-scan needs to be sufficiently selective.
# See the private email from Adi Zaimi to drh@sqlite.org on 2014-09-22.
#
db close
forcedelete test.db
sqlite3 db test.db
do_execsql_test skipscan1-6.1 {
  CREATE TABLE t1(a,b,c,d,e,f,g,h varchar(300));
  CREATE INDEX t1ab ON t1(a,b);
  ANALYZE sqlite_master;
  -- Only two distinct values for the skip-scan column.  Skip-scan is not used.
  INSERT INTO sqlite_stat1 VALUES('t1','t1ab','500000 250000 125000');
  ANALYZE sqlite_master;
  EXPLAIN QUERY PLAN SELECT * FROM t1 WHERE b=1;
} {~/ANY/}
do_execsql_test skipscan1-6.2 {
  -- Four distinct values for the skip-scan column.  Skip-scan is used.
  UPDATE sqlite_stat1 SET stat='500000 250000 62500';
  ANALYZE sqlite_master;
  EXPLAIN QUERY PLAN SELECT * FROM t1 WHERE b=1;
} {/ANY.a. AND b=/}
do_execsql_test skipscan1-6.3 {
  -- Two distinct values for the skip-scan column again.  Skip-scan is not used.
  UPDATE sqlite_stat1 SET stat='500000 125000 62500';
  ANALYZE sqlite_master;
  EXPLAIN QUERY PLAN SELECT * FROM t1 WHERE b=1;
} {~/ANY/}

finish_test

  foreach {tn2 q res} {
    1 { c BETWEEN 'd' AND 'e' }       {/*ANY(a) AND ANY(b) AND c>? AND c<?*/}
    2 { c BETWEEN 'b' AND 'r' }       {/*SCAN TABLE t2*/}
    3 { c > 'q' }                     {/*ANY(a) AND ANY(b) AND c>?*/}
    4 { c > 'e' }                     {/*SCAN TABLE t2*/}
    5 { c < 'q' }                     {/*SCAN TABLE t2*/}
    4 { c < 'e' }                     {/*ANY(a) AND ANY(b) AND c<?*/}
  } {
    set sql "EXPLAIN QUERY PLAN SELECT * FROM t2 WHERE $q" 
    do_execsql_test 2.$tn.$tn2 $sql $res
  }

}

................................................................................
  6 "b < 'zzz'"                        {/*SCAN TABLE t3*/}
} {
  set sql "EXPLAIN QUERY PLAN SELECT * FROM t3 WHERE $q" 
  do_execsql_test 3.3.$tn $sql $res
}

finish_test

  foreach {tn2 q res} {
    1 { c BETWEEN 'd' AND 'e' }       {/*ANY(a) AND ANY(b) AND c>? AND c<?*/}
    2 { c BETWEEN 'b' AND 'r' }       {/*SCAN TABLE t2*/}
    3 { c > 'q' }                     {/*ANY(a) AND ANY(b) AND c>?*/}
    4 { c > 'e' }                     {/*SCAN TABLE t2*/}
    5 { c < 'q' }                     {/*SCAN TABLE t2*/}
    6 { c < 'c' }                     {/*ANY(a) AND ANY(b) AND c<?*/}
  } {
    set sql "EXPLAIN QUERY PLAN SELECT * FROM t2 WHERE $q" 
    do_execsql_test 2.$tn.$tn2 $sql $res
  }

}

................................................................................
  6 "b < 'zzz'"                        {/*SCAN TABLE t3*/}
} {
  set sql "EXPLAIN QUERY PLAN SELECT * FROM t3 WHERE $q" 
  do_execsql_test 3.3.$tn $sql $res
}

finish_test

#
# This file implements regression tests for SQLite library.  The
# focus of this file is testing the sorter (code in vdbesort.c).
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl


# Create a bunch of data to sort against
#
do_test sort-1.0 {
  execsql {
    CREATE TABLE t1(
       n int,

#
# This file implements regression tests for SQLite library.  The
# focus of this file is testing the sorter (code in vdbesort.c).
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix sort

# Create a bunch of data to sort against
#
do_test sort-1.0 {
  execsql {
    CREATE TABLE t1(
       n int,

    nElem, nElem
  );
  speedtest1_run();
  speedtest1_end_test();

}


/* Generate two numbers between 1 and mx.  The first number is less than
** the second.  Usually the numbers are near each other but can sometimes
** be far apart.
*/
static void twoCoords(
  int p1, int p2,                   /* Parameters adjusting sizes */
  unsigned mx,                      /* Range of 1..mx */
................................................................................
  if( speedtest1_random()%p2==0 ) span = mx/2;
  d = speedtest1_random()%span + 1;
  x0 = speedtest1_random()%(mx-d) + 1;
  x1 = x0 + d;
  *pX0 = x0;
  *pX1 = x1;
}



/* The following routine is an R-Tree geometry callback.  It returns
** true if the object overlaps a slice on the Y coordinate between the
** two values given as arguments.  In other words
**
**     SELECT count(*) FROM rt1 WHERE id MATCH xslice(10,20);
**
** Is the same as saying:
................................................................................
  int nCoord,
  double *aCoord,
  int *pRes
){
  *pRes = aCoord[3]>=p->aParam[0] && aCoord[2]<=p->aParam[1];
  return SQLITE_OK;
}



/*
** A testset for the R-Tree virtual table
*/
void testset_rtree(int p1, int p2){
  unsigned i, n;
  unsigned mxCoord;
  unsigned x0, x1, y0, y1, z0, z1;
................................................................................
  speedtest1_prepare("SELECT * FROM rt1 WHERE id=?1");
  for(i=1; i<=n; i++){
    sqlite3_bind_int(g.pStmt, 1, i);
    speedtest1_run();
  }
  speedtest1_end_test();
}


/*
** A testset used for debugging speedtest1 itself.
*/
void testset_debug1(void){
  unsigned i, n;
  unsigned x1, x2;
................................................................................
  if( strcmp(zTSet,"main")==0 ){
    testset_main();
  }else if( strcmp(zTSet,"debug1")==0 ){
    testset_debug1();
  }else if( strcmp(zTSet,"cte")==0 ){
    testset_cte();
  }else if( strcmp(zTSet,"rtree")==0 ){

    testset_rtree(6, 147);




  }else{
    fatal_error("unknown testset: \"%s\"\nChoices: main debug1 cte rtree\n",
                 zTSet);
  }
  speedtest1_final();

  /* Database connection statistics printed after both prepared statements

    nElem, nElem
  );
  speedtest1_run();
  speedtest1_end_test();

}

#ifdef SQLITE_ENABLE_RTREE
/* Generate two numbers between 1 and mx.  The first number is less than
** the second.  Usually the numbers are near each other but can sometimes
** be far apart.
*/
static void twoCoords(
  int p1, int p2,                   /* Parameters adjusting sizes */
  unsigned mx,                      /* Range of 1..mx */
................................................................................
  if( speedtest1_random()%p2==0 ) span = mx/2;
  d = speedtest1_random()%span + 1;
  x0 = speedtest1_random()%(mx-d) + 1;
  x1 = x0 + d;
  *pX0 = x0;
  *pX1 = x1;
}
#endif

#ifdef SQLITE_ENABLE_RTREE
/* The following routine is an R-Tree geometry callback.  It returns
** true if the object overlaps a slice on the Y coordinate between the
** two values given as arguments.  In other words
**
**     SELECT count(*) FROM rt1 WHERE id MATCH xslice(10,20);
**
** Is the same as saying:
................................................................................
  int nCoord,
  double *aCoord,
  int *pRes
){
  *pRes = aCoord[3]>=p->aParam[0] && aCoord[2]<=p->aParam[1];
  return SQLITE_OK;
}
#endif /* SQLITE_ENABLE_RTREE */

#ifdef SQLITE_ENABLE_RTREE
/*
** A testset for the R-Tree virtual table
*/
void testset_rtree(int p1, int p2){
  unsigned i, n;
  unsigned mxCoord;
  unsigned x0, x1, y0, y1, z0, z1;
................................................................................
  speedtest1_prepare("SELECT * FROM rt1 WHERE id=?1");
  for(i=1; i<=n; i++){
    sqlite3_bind_int(g.pStmt, 1, i);
    speedtest1_run();
  }
  speedtest1_end_test();
}
#endif /* SQLITE_ENABLE_RTREE */

/*
** A testset used for debugging speedtest1 itself.
*/
void testset_debug1(void){
  unsigned i, n;
  unsigned x1, x2;
................................................................................
  if( strcmp(zTSet,"main")==0 ){
    testset_main();
  }else if( strcmp(zTSet,"debug1")==0 ){
    testset_debug1();
  }else if( strcmp(zTSet,"cte")==0 ){
    testset_cte();
  }else if( strcmp(zTSet,"rtree")==0 ){
#ifdef SQLITE_ENABLE_RTREE
    testset_rtree(6, 147);
#else
    fatal_error("compile with -DSQLITE_ENABLE_RTREE to enable "
                "the R-Tree tests\n");
#endif
  }else{
    fatal_error("unknown testset: \"%s\"\nChoices: main debug1 cte rtree\n",
                 zTSet);
  }
  speedtest1_final();

  /* Database connection statistics printed after both prepared statements

} $SQLITE_MAX_ATTACHED
do_test sqllimits1-1.9 {
  sqlite3_limit db SQLITE_LIMIT_LIKE_PATTERN_LENGTH -1
} $SQLITE_MAX_LIKE_PATTERN_LENGTH
do_test sqllimits1-1.10 {
  sqlite3_limit db SQLITE_LIMIT_VARIABLE_NUMBER -1
} $SQLITE_MAX_VARIABLE_NUMBER








# Limit parameters out of range.
#
do_test sqllimits1-1.20 {
  sqlite3_limit db SQLITE_LIMIT_TOOSMALL 123
} {-1}
do_test sqllimits1-1.21 {

} $SQLITE_MAX_ATTACHED
do_test sqllimits1-1.9 {
  sqlite3_limit db SQLITE_LIMIT_LIKE_PATTERN_LENGTH -1
} $SQLITE_MAX_LIKE_PATTERN_LENGTH
do_test sqllimits1-1.10 {
  sqlite3_limit db SQLITE_LIMIT_VARIABLE_NUMBER -1
} $SQLITE_MAX_VARIABLE_NUMBER
do_test sqllimits1-1.11 {
  sqlite3_limit db SQLITE_LIMIT_TRIGGER_DEPTH -1
} $SQLITE_MAX_TRIGGER_DEPTH
do_test sqllimits1-1.12 {
  sqlite3_limit db SQLITE_LIMIT_WORKER_THREADS 99999
  sqlite3_limit db SQLITE_LIMIT_WORKER_THREADS -1
} $SQLITE_MAX_WORKER_THREADS

# Limit parameters out of range.
#
do_test sqllimits1-1.20 {
  sqlite3_limit db SQLITE_LIMIT_TOOSMALL 123
} {-1}
do_test sqllimits1-1.21 {

}

do_execsql_test 2.2 {
  SELECT * 
  FROM (SELECT * FROM t4 ORDER BY a LIMIT -1 OFFSET 1) 
  LIMIT (SELECT a FROM t5)
} {2 3   3 6   4 10}















































finish_test

}

do_execsql_test 2.2 {
  SELECT * 
  FROM (SELECT * FROM t4 ORDER BY a LIMIT -1 OFFSET 1) 
  LIMIT (SELECT a FROM t5)
} {2 3   3 6   4 10}

############################################################################
# Ticket http://www.sqlite.org/src/info/d11a6e908f (2014-09-20)
# Query planner fault on three-way nested join with compound inner SELECT 
#
do_execsql_test 3.0 {
  DROP TABLE IF EXISTS t1;
  DROP TABLE IF EXISTS t2;
  CREATE TABLE t1 (id INTEGER PRIMARY KEY, data TEXT);
  INSERT INTO t1(id,data) VALUES(9,'nine-a');
  INSERT INTO t1(id,data) VALUES(10,'ten-a');
  INSERT INTO t1(id,data) VALUES(11,'eleven-a');
  CREATE TABLE t2 (id INTEGER PRIMARY KEY, data TEXT);
  INSERT INTO t2(id,data) VALUES(9,'nine-b');
  INSERT INTO t2(id,data) VALUES(10,'ten-b');
  INSERT INTO t2(id,data) VALUES(11,'eleven-b');
  
  SELECT id FROM (
    SELECT id,data FROM (
       SELECT * FROM t1 UNION ALL SELECT * FROM t2
    )
    WHERE id=10 ORDER BY data
  );
} {10 10}
do_execsql_test 3.1 {
  SELECT data FROM (
     SELECT 'dummy', data FROM (
       SELECT data FROM t1 UNION ALL SELECT data FROM t1
     ) ORDER BY data
  );
} {eleven-a eleven-a nine-a nine-a ten-a ten-a}
do_execsql_test 3.2 {
  DROP TABLE IF EXISTS t3;
  DROP TABLE IF EXISTS t4;
  CREATE TABLE t3(id INTEGER, data TEXT);
  CREATE TABLE t4(id INTEGER, data TEXT);
  INSERT INTO t3 VALUES(4, 'a'),(2,'c');
  INSERT INTO t4 VALUES(3, 'b'),(1,'d');

  SELECT data, id FROM (
    SELECT id, data FROM (
       SELECT * FROM t3 UNION ALL SELECT * FROM t4
    ) ORDER BY data
  );
} {a 4 b 3 c 2 d 1}


finish_test

# 2014-10-11
#
# 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.
#
#*************************************************************************
#
# Test that ticket [ba7cbfaedc] has been fixed.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix tkt-ba7cbfaedc

do_execsql_test 1 {
  CREATE TABLE t1 (x, y);
  INSERT INTO t1 VALUES (3, 'a');
  INSERT INTO t1 VALUES (1, 'a'); 
  INSERT INTO t1 VALUES (2, 'b');
  INSERT INTO t1 VALUES (2, 'a');
  INSERT INTO t1 VALUES (3, 'b');
  INSERT INTO t1 VALUES (1, 'b'); 
}

do_execsql_test 1.1 {
  CREATE INDEX i1 ON t1(x, y);
}

foreach {n idx} {
  1 { CREATE INDEX i1 ON t1(x, y) }
  2 { CREATE INDEX i1 ON t1(x DESC, y) }
  3 { CREATE INDEX i1 ON t1(x, y DESC) }
  4 { CREATE INDEX i1 ON t1(x DESC, y DESC) }
} {
  catchsql { DROP INDEX i1 }
  execsql $idx
  foreach {tn q res} {
    1 "GROUP BY x, y ORDER BY x, y"            {1 a 1 b   2 a 2 b   3 a 3 b}
    2 "GROUP BY x, y ORDER BY x DESC, y"       {3 a 3 b   2 a 2 b   1 a 1 b}
    3 "GROUP BY x, y ORDER BY x, y DESC"       {1 b 1 a   2 b 2 a   3 b 3 a}
    4 "GROUP BY x, y ORDER BY x DESC, y DESC"  {3 b 3 a   2 b 2 a   1 b 1 a}
  } {
    do_execsql_test 1.$n.$tn "SELECT * FROM t1 $q" $res
  }
}

do_execsql_test 2.0 {
  drop table if exists t1;
  create table t1(id int);
  insert into t1(id) values(1),(2),(3),(4),(5);
  create index t1_idx_id on t1(id asc);
  select * from t1 group by id order by id;
  select * from t1 group by id order by id asc;
  select * from t1 group by id order by id desc;
} {
  1 2 3 4 5   1 2 3 4 5   5 4 3 2 1
}

finish_test

    append afterUnion $line\n
    set vlist {}
  } elseif {[llength $vlist]>0} {
    append line " "
    foreach v $vlist {
      regsub -all "(\[^a-zA-Z0-9>.\])${v}(\\W)" $line "\\1u.$sname.$v\\2" line
      regsub -all "(\[^a-zA-Z0-9>.\])${v}(\\W)" $line "\\1u.$sname.$v\\2" line





    }
    append afterUnion [string trimright $line]\n
  } elseif {$line=="" && [eof stdin]} {
    # no-op
  } else {
    append afterUnion $line\n
  }

    append afterUnion $line\n
    set vlist {}
  } elseif {[llength $vlist]>0} {
    append line " "
    foreach v $vlist {
      regsub -all "(\[^a-zA-Z0-9>.\])${v}(\\W)" $line "\\1u.$sname.$v\\2" line
      regsub -all "(\[^a-zA-Z0-9>.\])${v}(\\W)" $line "\\1u.$sname.$v\\2" line

      # The expressions above fail to catch instance of variable "abc" in
      # expressions like (32>abc). The following expression makes those
      # substitutions.
      regsub -all "(\[^-\])>${v}(\\W)" $line "\\1>u.$sname.$v\\2" line
    }
    append afterUnion [string trimright $line]\n
  } elseif {$line=="" && [eof stdin]} {
    # no-op
  } else {
    append afterUnion $line\n
  }