SQLite

    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_Last, iIdx, 0, -1);
  sqlite3VdbeAddOp3(v, OP_IdxInsert, iIdx, regRecord, 1);
  sqlite3VdbeAddOp3(v, OP_IdxInsert, iIdx, regRecord, 0);
  sqlite3VdbeChangeP5(v, OPFLAG_USESEEKRESULT);
  sqlite3ReleaseTempReg(pParse, regRecord);
  sqlite3VdbeAddOp2(v, OP_SorterNext, iSorter, addr2); VdbeCoverage(v);
  sqlite3VdbeJumpHere(v, addr1);

  sqlite3VdbeAddOp1(v, OP_Close, iTab);
  sqlite3VdbeAddOp1(v, OP_Close, iIdx);

static int xferOptimization(
  Parse *pParse,        /* Parser context */
  Table *pDest,         /* The table we are inserting into */
  Select *pSelect,      /* A SELECT statement to use as the data source */
  int onError,          /* How to handle constraint errors */
  int iDbDest           /* The database of pDest */
);

/*
** Return the conflict handling mode that should be used for index pIdx
** if the statement specified conflict mode overrideError.
**
** If the index is not a UNIQUE index, then the conflict handling mode is
** always OE_None. Otherwise, it is one of OE_Abort, OE_Rollback, OE_Fail, 
** OE_Ignore or OE_Replace.
*/
static u8 idxConflictMode(Index *pIdx, u8 overrideError){
  u8 ret = pIdx->onError;
  if( ret!=OE_None ){
    if( overrideError!=OE_Default ) ret = overrideError;
    if( ret==OE_Default ) ret = OE_Abort;
  }
  return ret;
}

/*
** This routine is called to handle SQL of the following forms:
**
**    insert into TABLE (IDLIST) values(EXPRLIST)
**    insert into TABLE (IDLIST) select
**

  int i, j, idx;        /* Loop counters */
  Vdbe *v;              /* Generate code into this virtual machine */
  Index *pIdx;          /* For looping over indices of the table */
  int nColumn;          /* Number of columns in the data */
  int nHidden = 0;      /* Number of hidden columns if TABLE is virtual */
  int iDataCur = 0;     /* VDBE cursor that is the main data repository */
  int iIdxCur = 0;      /* First index cursor */
  int iSortCur = 0;     /* First sorter cursor (for INSERT INTO ... SELECT) */
  int ipkColumn = -1;   /* Column that is the INTEGER PRIMARY KEY */
  int endOfLoop;        /* Label for the end of the insertion loop */
  int srcTab = 0;       /* Data comes from this temporary cursor if >=0 */
  int addrInsTop = 0;   /* Jump to label "D" */
  int addrCont = 0;     /* Top of insert loop. Label "C" in templates 3 and 4 */
  SelectDest dest;      /* Destination for SELECT on rhs of INSERT */
  int iDb;              /* Index of database holding TABLE */

    aRegIdx = sqlite3DbMallocRaw(db, sizeof(int)*(nIdx+1));
    if( aRegIdx==0 ){
      goto insert_cleanup;
    }
    for(i=0; i<nIdx; i++){
      aRegIdx[i] = ++pParse->nMem;
    }

    /* If this is an INSERT INTO ... SELECT statement on a non-virtual table,
    ** check if it is possible to defer updating any indexes until after
    ** all rows have been processed. If it is, the index keys can be sorted
    ** before they are inserted into the index b-tree, which is more efficient
    ** for large inserts. It is possible to defer updating the indexes if:
    **
    **    * there are no triggers to fire, and
    **    * no foreign key processing to perform, and
    **    * the on-conflict mode used for all UNIQUE and PRIMARY KEY indexes, 
    **      including INTEGER PRIMARY KEYs, is either ROLLBACK or ABORT.
    */
    if( pSelect 
     && 0==(pSelect->selFlags & SF_Values)
     && onError!=OE_Fail && onError!=OE_Replace && onError!=OE_Ignore
     && !IsVirtual(pTab) 
     && pTrigger==0 
     && 0==sqlite3FkRequired(pParse, pTab, 0, 0) 
    ){
      for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
        u8 oe = idxConflictMode(pIdx, onError);
        if( oe==OE_Fail || oe==OE_Replace || oe==OE_Ignore ) break;
        assert( oe==OE_None || oe==OE_Abort || oe==OE_Rollback );
      }
      if( pIdx==0 ){
        /* This statement can sort the set of new keys for each index before
        ** writing them into the b-tree on disk. So open a sorter for each
        ** index on the table. */
        iSortCur = pParse->nTab;
        for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
          sqlite3VdbeAddOp1(v, OP_SorterOpen, pParse->nTab++);
          sqlite3VdbeSetP4KeyInfo(pParse, pIdx);
        }
        assert( iSortCur>0 );
      }
    }
  }

  /* This is the top of the main insertion loop */
  if( useTempTable ){
    /* This block codes the top of loop only.  The complete loop is the
    ** following pseudocode (template 4):
    **

      sqlite3VdbeAddOp4(v, OP_VUpdate, 1, pTab->nCol+2, regIns, pVTab, P4_VTAB);
      sqlite3VdbeChangeP5(v, onError==OE_Default ? OE_Abort : onError);
      sqlite3MayAbort(pParse);
    }else
#endif
    {
      int isReplace;    /* Set to true if constraints may cause a replace */
      int iIdxBase = iIdxCur;
      int op = OP_IdxInsert;
      sqlite3GenerateConstraintChecks(pParse, pTab, aRegIdx, iDataCur, iIdxCur,
          regIns, 0, ipkColumn>=0, onError, endOfLoop, &isReplace
          regIns, 0, ipkColumn>=0, onError, endOfLoop, iSortCur!=0, &isReplace
      );
      if( iSortCur ){
        iIdxBase = iSortCur;
        isReplace = 1;
        op = OP_SorterInsert;
      }
      sqlite3FkCheck(pParse, pTab, 0, regIns, 0, 0);
      sqlite3CompleteInsertion(pParse, pTab, iDataCur, iIdxCur,
                               regIns, aRegIdx, 0, appendFlag, isReplace==0);
      sqlite3CompleteInsertion(pParse, pTab, 
          iDataCur, iIdxBase, regIns, op, aRegIdx, 0, appendFlag, isReplace==0
      );
    }
  }

  /* Update the count of rows that are inserted
  */
  if( (db->flags & SQLITE_CountRows)!=0 ){
    sqlite3VdbeAddOp2(v, OP_AddImm, regRowCount, 1);

    sqlite3VdbeAddOp1(v, OP_Close, srcTab);
  }else if( pSelect ){
    sqlite3VdbeAddOp2(v, OP_Goto, 0, addrCont);
    sqlite3VdbeJumpHere(v, addrInsTop);
  }

  if( !IsVirtual(pTab) && !isView ){
    /* If new index keys were written into sorter objects instead of
    ** directly to the index b-trees, copy them from the sorters into the
    ** indexes now. And close all the sorters. */
    if( iSortCur ){
      int iTmp = sqlite3GetTempReg(pParse);
      for(idx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, idx++){
        int oe = idxConflictMode(pIdx, onError);
        int iCur = iSortCur + idx;
        int iIdx = iIdxCur + idx;
        int addr = sqlite3VdbeAddOp1(v, OP_SorterSort, iCur);
        sqlite3VdbeAddOp3(v, OP_SorterData, iCur, iTmp, iIdx);
        if( oe!=OE_None ){
          int nField = -1 * pIdx->nKeyCol;
          int jmp = sqlite3VdbeCurrentAddr(v)+2;
          sqlite3VdbeAddOp4Int(v, OP_NoConflict, iIdx, jmp, iTmp, nField);
          sqlite3UniqueConstraint(pParse, oe, pIdx);
        }
        sqlite3VdbeAddOp2(v, OP_IdxInsert, iIdx, iTmp); 
        if( oe!=OE_None ) sqlite3VdbeChangeP5(v, OPFLAG_USESEEKRESULT);
        sqlite3VdbeAddOp2(v, OP_SorterNext, iCur, addr+1); VdbeCoverage(v);
        sqlite3VdbeJumpHere(v, addr);
        sqlite3VdbeAddOp1(v, OP_Close, iCur);
      }
      sqlite3ReleaseTempReg(pParse, iTmp);
    }

    /* Close all tables opened */
    if( iDataCur<iIdxCur ) sqlite3VdbeAddOp1(v, OP_Close, iDataCur);
    for(idx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, idx++){
      sqlite3VdbeAddOp1(v, OP_Close, idx+iIdxCur);
    }
  }

  int iDataCur,        /* Canonical data cursor (main table or PK index) */
  int iIdxCur,         /* First index cursor */
  int regNewData,      /* First register in a range holding values to insert */
  int regOldData,      /* Previous content.  0 for INSERTs */
  u8 pkChng,           /* Non-zero if the rowid or PRIMARY KEY changed */
  u8 overrideError,    /* Override onError to this if not OE_Default */
  int ignoreDest,      /* Jump to this label on an OE_Ignore resolution */
  int ignoreUnique,    /* Do not enforce UNIQUE constraints */
  int *pbMayReplace    /* OUT: Set to true if constraint may cause a replace */
){
  Vdbe *v;             /* VDBE under constrution */
  Index *pIdx;         /* Pointer to one of the indices */
  Index *pPk = 0;      /* The PRIMARY KEY index */
  sqlite3 *db;         /* Database connection */
  int i;               /* loop counter */

    ** logic below can all be skipped. */
    if( isUpdate && pPk==pIdx && pkChng==0 ){
      sqlite3VdbeResolveLabel(v, addrUniqueOk);
      continue;
    }

    /* Find out what action to take in case there is a uniqueness conflict */
    onError = pIdx->onError;
    if( onError==OE_None ){ 
    onError = idxConflictMode(pIdx, overrideError);
    if( onError==OE_None || ignoreUnique ){ 
      sqlite3ReleaseTempRange(pParse, regIdx, pIdx->nColumn);
      sqlite3VdbeResolveLabel(v, addrUniqueOk);
      continue;  /* pIdx is not a UNIQUE index */
    }
    if( overrideError!=OE_Default ){
      onError = overrideError;
    }else if( onError==OE_Default ){
      onError = OE_Abort;
    }
    
    /* Check to see if the new index entry will be unique */
    sqlite3VdbeAddOp4Int(v, OP_NoConflict, iThisCur, addrUniqueOk,
                         regIdx, pIdx->nKeyCol); VdbeCoverage(v);

    /* Generate code to handle collisions */
    regR = (pIdx==pPk) ? regIdx : sqlite3GetTempRange(pParse, nPkField);

*/
void sqlite3CompleteInsertion(
  Parse *pParse,      /* The parser context */
  Table *pTab,        /* the table into which we are inserting */
  int iDataCur,       /* Cursor of the canonical data source */
  int iIdxCur,        /* First index cursor */
  int regNewData,     /* Range of content */
  int idxop,          /* Opcode to use to write to "indexes" */
  int *aRegIdx,       /* Register used by each index.  0 for unused indices */
  int isUpdate,       /* True for UPDATE, False for INSERT */
  int appendBias,     /* True if this is likely to be an append */
  int useSeekResult   /* True to set the USESEEKRESULT flag on OP_[Idx]Insert */
){
  Vdbe *v;            /* Prepared statements under construction */
  Index *pIdx;        /* An index being inserted or updated */
  u8 pik_flags;       /* flag values passed to the btree insert */
  int regData;        /* Content registers (after the rowid) */
  int regRec;         /* Register holding assembled record for the table */
  int i;              /* Loop counter */
  u8 bAffinityDone = 0; /* True if OP_Affinity has been run already */

  assert( idxop==OP_IdxInsert || idxop==OP_SorterInsert );

  v = sqlite3GetVdbe(pParse);
  assert( v!=0 );
  assert( pTab->pSelect==0 );  /* This table is not a VIEW */
  for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
    if( aRegIdx[i]==0 ) continue;
    bAffinityDone = 1;
    if( pIdx->pPartIdxWhere ){
      sqlite3VdbeAddOp2(v, OP_IsNull, aRegIdx[i], sqlite3VdbeCurrentAddr(v)+2);
      VdbeCoverage(v);
    }
    sqlite3VdbeAddOp2(v, OP_IdxInsert, iIdxCur+i, aRegIdx[i]);
    sqlite3VdbeAddOp2(v, idxop, iIdxCur+i, aRegIdx[i]);
    pik_flags = 0;
    if( useSeekResult ) pik_flags = OPFLAG_USESEEKRESULT;
    if( IsPrimaryKeyIndex(pIdx) && !HasRowid(pTab) ){
      assert( pParse->nested==0 );
      pik_flags |= OPFLAG_NCHANGE;
    }
    if( pik_flags )  sqlite3VdbeChangeP5(v, pik_flags);

static int xferOptimization(
  Parse *pParse,        /* Parser context */
  Table *pDest,         /* The table we are inserting into */
  Select *pSelect,      /* A SELECT statement to use as the data source */
  int onError,          /* How to handle constraint errors */
  int iDbDest           /* The database of pDest */
){
  sqlite3 *db = pParse->db;
  ExprList *pEList;                /* The result set of the SELECT */
  Table *pSrc;                     /* The table in the FROM clause of SELECT */
  Index *pSrcIdx, *pDestIdx;       /* Source and destination indices */
  struct SrcList_item *pItem;      /* An element of pSelect->pSrc */
  int i;                           /* Loop counter */
  int iDbSrc;                      /* The database of pSrc */
  int iSrc, iDest;                 /* Cursors from source and destination */

  /* Disallow the transfer optimization if the destination table constains
  ** any foreign key constraints.  This is more restrictive than necessary.
  ** But the main beneficiary of the transfer optimization is the VACUUM 
  ** command, and the VACUUM command disables foreign key constraints.  So
  ** the extra complication to make this rule less restrictive is probably
  ** not worth the effort.  Ticket [6284df89debdfa61db8073e062908af0c9b6118e]
  */
  if( (pParse->db->flags & SQLITE_ForeignKeys)!=0 && pDest->pFKey!=0 ){
  if( (db->flags & SQLITE_ForeignKeys)!=0 && pDest->pFKey!=0 ){
    return 0;
  }
#endif
  if( (pParse->db->flags & SQLITE_CountRows)!=0 ){
  if( (db->flags & SQLITE_CountRows)!=0 ){
    return 0;  /* xfer opt does not play well with PRAGMA count_changes */
  }

  /* If we get this far, it means that the xfer optimization is at
  ** least a possibility, though it might only work if the destination
  ** table (tab1) is initially empty.
  */
#ifdef SQLITE_TEST
  sqlite3_xferopt_count++;
#endif
  iDbSrc = sqlite3SchemaToIndex(pParse->db, pSrc->pSchema);
  iDbSrc = sqlite3SchemaToIndex(db, pSrc->pSchema);
  v = sqlite3GetVdbe(pParse);
  sqlite3CodeVerifySchema(pParse, iDbSrc);
  iSrc = pParse->nTab++;
  iDest = pParse->nTab++;
  regAutoinc = autoIncBegin(pParse, iDbDest, pDest);
  regData = sqlite3GetTempReg(pParse);
  regRowid = sqlite3GetTempReg(pParse);
  sqlite3OpenTable(pParse, iDest, iDbDest, pDest, OP_OpenWrite);
  assert( HasRowid(pDest) || destHasUniqueIdx );
  if( (db->flags & SQLITE_Vacuum)==0 && (
  if( (pDest->iPKey<0 && pDest->pIndex!=0)          /* (1) */
      (pDest->iPKey<0 && pDest->pIndex!=0)          /* (1) */
   || destHasUniqueIdx                              /* (2) */
   || (onError!=OE_Abort && onError!=OE_Rollback)   /* (3) */
  ){
  )){
    /* In some circumstances, we are able to run the xfer optimization
    ** only if the destination table is initially empty.  This code makes
    ** that determination.  Conditions under which the destination must
    ** only if the destination table is initially empty. Unless the
    ** SQLITE_Vacuum flag is set, this block generates code to make
    ** that determination. If SQLITE_Vacuum is set, then the destination
    ** table is always empty.
    **
    ** Conditions under which the destination must be empty:
    ** be empty:
    **
    ** (1) There is no INTEGER PRIMARY KEY but there are indices.
    **     (If the destination is not initially empty, the rowid fields
    **     of index entries might need to change.)
    **
    ** (2) The destination has a unique index.  (The xfer optimization 
    **     is unable to test uniqueness.)

    sqlite3VdbeAddOp2(v, OP_Close, iSrc, 0);
    sqlite3VdbeAddOp2(v, OP_Close, iDest, 0);
  }else{
    sqlite3TableLock(pParse, iDbDest, pDest->tnum, 1, pDest->zName);
    sqlite3TableLock(pParse, iDbSrc, pSrc->tnum, 0, pSrc->zName);
  }
  for(pDestIdx=pDest->pIndex; pDestIdx; pDestIdx=pDestIdx->pNext){
    u8 useSeekResult = 0;
    for(pSrcIdx=pSrc->pIndex; ALWAYS(pSrcIdx); pSrcIdx=pSrcIdx->pNext){
      if( xferCompatibleIndex(pDestIdx, pSrcIdx) ) break;
    }
    assert( pSrcIdx );
    sqlite3VdbeAddOp3(v, OP_OpenRead, iSrc, pSrcIdx->tnum, iDbSrc);
    sqlite3VdbeSetP4KeyInfo(pParse, pSrcIdx);
    VdbeComment((v, "%s", pSrcIdx->zName));
    sqlite3VdbeAddOp3(v, OP_OpenWrite, iDest, pDestIdx->tnum, iDbDest);
    sqlite3VdbeSetP4KeyInfo(pParse, pDestIdx);
    sqlite3VdbeChangeP5(v, OPFLAG_BULKCSR);
    VdbeComment((v, "%s", pDestIdx->zName));
    addr1 = sqlite3VdbeAddOp2(v, OP_Rewind, iSrc, 0); VdbeCoverage(v);
    sqlite3VdbeAddOp2(v, OP_RowKey, iSrc, regData);
    if( db->flags & SQLITE_Vacuum ){
      /* This INSERT command is part of a VACUUM operation, which guarantees
      ** that the destination table is empty. If all indexed columns use
      ** collation sequence BINARY, then it can also be assumed that the
      ** index will be populated by inserting keys in strictly sorted 
      ** order. In this case, instead of seeking within the b-tree as part
      ** of every OP_IdxInsert opcode, an OP_Last is added before the
      ** OP_IdxInsert to seek to the point within the b-tree where each key 
      ** should be inserted. This is faster.
      **
      ** If any of the indexed columns use a collation sequence other than
      ** BINARY, this optimization is disabled. This is because the user 
      ** might change the definition of a collation sequence and then run
      ** a VACUUM command. In that case keys may not be written in strictly
      ** sorted order.  */
      int i;
      for(i=0; i<pSrcIdx->nColumn; i++){
        char *zColl = pSrcIdx->azColl[i];
        if( zColl && sqlite3_stricmp("BINARY", zColl) ) break;
      }
      if( i==pSrcIdx->nColumn ){
        useSeekResult = OPFLAG_USESEEKRESULT;
        sqlite3VdbeAddOp3(v, OP_Last, iDest, 0, -1);
      }
    }
    sqlite3VdbeAddOp3(v, OP_IdxInsert, iDest, regData, 1);
    sqlite3VdbeChangeP5(v, useSeekResult);
    sqlite3VdbeAddOp2(v, OP_Next, iSrc, addr1+1); VdbeCoverage(v);
    sqlite3VdbeJumpHere(v, addr1);
    sqlite3VdbeAddOp2(v, OP_Close, iSrc, 0);
    sqlite3VdbeAddOp2(v, OP_Close, iDest, 0);
  }
  if( emptySrcTest ) sqlite3VdbeJumpHere(v, emptySrcTest);
  sqlite3ReleaseTempReg(pParse, regRowid);

#define SQLITE_AutoIndex      0x00100000  /* Enable automatic indexes */
#define SQLITE_PreferBuiltin  0x00200000  /* Preference to built-in funcs */
#define SQLITE_LoadExtension  0x00400000  /* Enable load_extension */
#define SQLITE_EnableTrigger  0x00800000  /* True to enable triggers */
#define SQLITE_DeferFKs       0x01000000  /* Defer all FK constraints */
#define SQLITE_QueryOnly      0x02000000  /* Disable database changes */
#define SQLITE_VdbeEQP        0x04000000  /* Debug EXPLAIN QUERY PLAN */
#define SQLITE_Vacuum         0x08000000  /* Currently in a VACUUM */


/*
** Bits of the sqlite3.dbOptFlags field that are used by the
** sqlite3_test_control(SQLITE_TESTCTRL_OPTIMIZATIONS,...) interface to
** selectively disable various optimizations.
*/

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 sqlite3ResolvePartIdxLabel(Parse*,int);
void sqlite3GenerateConstraintChecks(Parse*,Table*,int*,int,int,int,int,
                                     u8,u8,int,int*);
void sqlite3CompleteInsertion(Parse*,Table*,int,int,int,int*,int,int,int);
                                     u8,u8,int,int,int*);
void sqlite3CompleteInsertion(Parse*,Table*,int,int,int,int,int*,int,int,int);
int sqlite3OpenTableAndIndices(Parse*, Table*, int, int, u8*, int*, int*);
void sqlite3BeginWriteOperation(Parse*, int, int);
void sqlite3MultiWrite(Parse*);
void sqlite3MayAbort(Parse*);
void sqlite3HaltConstraint(Parse*, int, int, char*, i8, u8);
void sqlite3UniqueConstraint(Parse*, int, Index*);
void sqlite3RowidConstraint(Parse*, int, Table*);

  if( !isView ){
    int j1 = 0;           /* Address of jump instruction */
    int bReplace = 0;     /* True if REPLACE conflict resolution might happen */

    /* Do constraint checks. */
    assert( regOldRowid>0 );
    sqlite3GenerateConstraintChecks(pParse, pTab, aRegIdx, iDataCur, iIdxCur,
        regNewRowid, regOldRowid, chngKey, onError, labelContinue, &bReplace);
        regNewRowid, regOldRowid, chngKey, onError, labelContinue, 0,&bReplace);

    /* Do FK constraint checks. */
    if( hasFK ){
      sqlite3FkCheck(pParse, pTab, regOldRowid, 0, aXRef, chngKey);
    }

    /* Delete the index entries associated with the current record.  */

    if( hasFK ){
      sqlite3FkCheck(pParse, pTab, 0, regNewRowid, aXRef, chngKey);
    }
  
    /* Insert the new index entries and the new record. */
    sqlite3CompleteInsertion(pParse, pTab, iDataCur, iIdxCur,
                             regNewRowid, aRegIdx, 1, 0, 0);
                             regNewRowid, OP_IdxInsert, aRegIdx, 1, 0, 0);

    /* Do any ON CASCADE, SET NULL or SET DEFAULT operations required to
    ** handle rows (possibly in other tables) that refer via a foreign key
    ** to the row just updated. */ 
    if( hasFK ){
      sqlite3FkActions(pParse, pTab, pChanges, regOldRowid, aXRef, chngKey);
    }

      "  FROM sqlite_master WHERE sql LIKE 'CREATE UNIQUE INDEX %'");
  if( rc!=SQLITE_OK ) goto end_of_vacuum;

  /* Loop through the tables in the main database. For each, do
  ** an "INSERT INTO vacuum_db.xxx SELECT * FROM main.xxx;" to copy
  ** the contents to the temporary database.
  */
  assert( (db->flags & SQLITE_Vacuum)==0 );
  db->flags |= SQLITE_Vacuum;
  rc = execExecSql(db, pzErrMsg,
      "SELECT 'INSERT INTO vacuum_db.' || quote(name) "
      "|| ' SELECT * FROM main.' || quote(name) || ';'"
      "FROM main.sqlite_master "
      "WHERE type = 'table' AND name!='sqlite_sequence' "
      "  AND coalesce(rootpage,1)>0"
  );
  assert( (db->flags & SQLITE_Vacuum)!=0 );
  db->flags &= ~SQLITE_Vacuum;
  if( rc!=SQLITE_OK ) goto end_of_vacuum;

  /* Copy over the sequence table
  */
  rc = execExecSql(db, pzErrMsg,
      "SELECT 'DELETE FROM vacuum_db.' || quote(name) || ';' "
      "FROM vacuum_db.sqlite_master WHERE name='sqlite_sequence' "

** string that the register itself controls.  In other words, it
** converts an MEM_Ephem string into a string with P.z==P.zMalloc.
*/
#define Deephemeralize(P) \
   if( ((P)->flags&MEM_Ephem)!=0 \
       && sqlite3VdbeMemMakeWriteable(P) ){ goto no_mem;}

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

/*
** Allocate VdbeCursor number iCur.  Return a pointer to it.  Return NULL
** if we run out of memory.
*/
static VdbeCursor *allocateCursor(

** See also: Found, NotExists, NoConflict
*/
/* Opcode: NoConflict P1 P2 P3 P4 *
** Synopsis: key=r[P3@P4]
**
** If P4==0 then register P3 holds a blob constructed by MakeRecord.  If
** P4>0 then register P3 is the first of P4 registers that form an unpacked
** record.
** record. If P4<0, then P3 holds a blob constructed by MakeRecord, but
** only the first |P4| fields should be considered.
** 
** Cursor P1 is on an index btree.  If the record identified by P3 and P4
** contains any NULL value, jump immediately to P2.  If all terms of the
** record are not-NULL then a check is done to determine if any row in the
** P1 index btree has a matching key prefix.  If there are no matches, jump
** immediately to P2.  If there is a match, fall through and leave the P1
** cursor pointing to the matching row.

    pIdxKey = sqlite3VdbeAllocUnpackedRecord(
        pC->pKeyInfo, aTempRec, sizeof(aTempRec), &pFree
    );
    if( pIdxKey==0 ) goto no_mem;
    assert( pIn3->flags & MEM_Blob );
    ExpandBlob(pIn3);
    sqlite3VdbeRecordUnpack(pC->pKeyInfo, pIn3->n, pIn3->z, pIdxKey);
    if( pOp->p4.i<0 ){
      pIdxKey->nField = pOp->p4.i * -1;
    }
  }
  pIdxKey->default_rc = 0;
  if( pOp->opcode==OP_NoConflict ){
    /* For the OP_NoConflict opcode, take the jump if any of the
    ** input fields are NULL, since any key with a NULL will not
    ** conflict */
    for(ii=0; ii<pIdxKey->nField; ii++){
      if( pIdxKey->aMem[ii].flags & MEM_Null ){
        pc = pOp->p2 - 1; VdbeBranchTaken(1,2);
        break;
      }
    }
  }
  rc = sqlite3BtreeMovetoUnpacked(pC->pCursor, pIdxKey, 0, 0, &res);
  if( pOp->p4.i==0 ){
  if( pOp->p4.i<=0 ){
    sqlite3DbFree(db, pFree);
  }
  if( rc!=SQLITE_OK ){
    break;
  }
  pC->seekResult = res;
  alreadyExists = (res==0);

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

/* Opcode: Last P1 P2 * * *
/* Opcode: Last P1 P2 P3 * *
**
** The next use of the Rowid or Column or Prev instruction for P1 
** will refer to the last entry in the database table or index.
** If the table or index is empty and P2>0, then jump immediately to P2.
** If P2 is 0 or if the table or index is not empty, fall through
** to the following instruction.
**

  pCrsr = pC->pCursor;
  res = 0;
  assert( pCrsr!=0 );
  rc = sqlite3BtreeLast(pCrsr, &res);
  pC->nullRow = (u8)res;
  pC->deferredMoveto = 0;
  pC->cacheStatus = CACHE_STALE;
  pC->seekResult = pOp->p3;
#ifdef SQLITE_DEBUG
  pC->seekOp = OP_Last;
#endif
  if( pOp->p2>0 ){
    VdbeBranchTaken(res!=0,2);
    if( res ) pc = pOp->p2 - 1;
  }

#ifndef SQLITE_OMIT_TRACE
  char *sqlite3VdbeExpandSql(Vdbe*, const char*);
#endif
int sqlite3MemCompare(const Mem*, const Mem*, const CollSeq*);

void sqlite3VdbeRecordUnpack(KeyInfo*,int,const void*,UnpackedRecord*);
int sqlite3VdbeRecordCompare(int,const void*,UnpackedRecord*);
int sqlite3VdbeRecordCompareWithSkip(int, const void *, UnpackedRecord *, int);
UnpackedRecord *sqlite3VdbeAllocUnpackedRecord(KeyInfo *, char *, int, char **);

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

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

** returned.
**
** If database corruption is discovered, set pPKey2->errCode to 
** SQLITE_CORRUPT and return 0. If an OOM error is encountered, 
** pPKey2->errCode is set to SQLITE_NOMEM and, if it is not NULL, the
** malloc-failed flag set on database handle (pPKey2->pKeyInfo->db).
*/
static int vdbeRecordCompareWithSkip(
int sqlite3VdbeRecordCompareWithSkip(
  int nKey1, const void *pKey1,   /* Left key */
  UnpackedRecord *pPKey2,         /* Right key */
  int bSkip                       /* If true, skip the first field */
){
  u32 d1;                         /* Offset into aKey[] of next data element */
  int i;                          /* Index of next field to compare */
  u32 szHdr1;                     /* Size of record header in bytes */

  );
  return pPKey2->default_rc;
}
int sqlite3VdbeRecordCompare(
  int nKey1, const void *pKey1,   /* Left key */
  UnpackedRecord *pPKey2          /* Right key */
){
  return vdbeRecordCompareWithSkip(nKey1, pKey1, pPKey2, 0);
  return sqlite3VdbeRecordCompareWithSkip(nKey1, pKey1, pPKey2, 0);
}


/*
** This function is an optimized version of sqlite3VdbeRecordCompare() 
** that (a) the first field of pPKey2 is an integer, and (b) the 
** size-of-header varint at the start of (pKey1/nKey1) fits in a single

  if( v>lhs ){
    res = pPKey2->r1;
  }else if( v<lhs ){
    res = pPKey2->r2;
  }else if( pPKey2->nField>1 ){
    /* The first fields of the two keys are equal. Compare the trailing 
    ** fields.  */
    res = vdbeRecordCompareWithSkip(nKey1, pKey1, pPKey2, 1);
    res = sqlite3VdbeRecordCompareWithSkip(nKey1, pKey1, pPKey2, 1);
  }else{
    /* The first fields of the two keys are equal and there are no trailing
    ** fields. Return pPKey2->default_rc in this case. */
    res = pPKey2->default_rc;
  }

  assert( vdbeRecordCompareDebug(nKey1, pKey1, pPKey2, res) );

    nCmp = MIN( pPKey2->aMem[0].n, nStr );
    res = memcmp(&aKey1[szHdr], pPKey2->aMem[0].z, nCmp);

    if( res==0 ){
      res = nStr - pPKey2->aMem[0].n;
      if( res==0 ){
        if( pPKey2->nField>1 ){
          res = vdbeRecordCompareWithSkip(nKey1, pKey1, pPKey2, 1);
          res = sqlite3VdbeRecordCompareWithSkip(nKey1, pKey1, pPKey2, 1);
        }else{
          res = pPKey2->default_rc;
        }
      }else if( res>0 ){
        res = pPKey2->r2;
      }else{
        res = pPKey2->r1;

**      to sqlite3ThreadJoin() is likely to block. Cases that are likely to
**      block provoke debugging output.
**
** In both cases, the effects of the main thread seeing (bDone==0) even
** after the thread has finished are not dire. So we don't worry about
** memory barriers and such here.
*/
typedef int (*SorterCompare)(SortSubtask*,int*,const void*,int,const void*,int);
struct SortSubtask {
  SQLiteThread *pThread;          /* Background thread, if any */
  int bDone;                      /* Set if thread is finished but not joined */
  VdbeSorter *pSorter;            /* Sorter that owns this sub-task */
  UnpackedRecord *pUnpacked;      /* Space to unpack a record */
  SorterList list;                /* List for thread to write to a PMA */
  int nPMA;                       /* Number of PMAs currently in file */
  SorterCompare xCompare;         /* Compare function to use */
  SorterFile file;                /* Temp file for level-0 PMAs */
  SorterFile file2;               /* Space for other PMAs */
};


/*
** Main sorter structure. A single instance of this is allocated for each 
** sorter cursor created by the VDBE.
**
** mxKeysize:
**   As records are added to the sorter by calls to sqlite3VdbeSorterWrite(),

  SorterList list;                /* List of in-memory records */
  int iMemory;                    /* Offset of free space in list.aMemory */
  int nMemory;                    /* Size of list.aMemory allocation in bytes */
  u8 bUsePMA;                     /* True if one or more PMAs created */
  u8 bUseThreads;                 /* True to use background threads */
  u8 iPrev;                       /* Previous thread used to flush PMA */
  u8 nTask;                       /* Size of aTask[] array */
  u8 typeMask;
  SortSubtask aTask[1];           /* One or more subtasks */
};

#define SORTER_TYPE_INTEGER 0x01
#define SORTER_TYPE_TEXT    0x02

/*
** An instance of the following object is used to read records out of a
** PMA, in sorted order.  The next key to be read is cached in nKey/aKey.
** aKey might point into aMap or into aBuffer.  If neither of those locations
** contain a contiguous representation of the key, then aAlloc is allocated
** and the key is copied into aAlloc and aKey is made to poitn to aAlloc.

  if( rc==SQLITE_OK ){
    rc = vdbePmaReaderNext(pReadr);
  }
  return rc;
}

/*
** A version of vdbeSorterCompare() that assumes that it has already been
** determined that the first field of key1 is equal to the first field of 
** key2.
*/
static int vdbeSorterCompareTail(
  SortSubtask *pTask,             /* Subtask context (for pKeyInfo) */
  int *pbKey2Cached,              /* True if pTask->pUnpacked is pKey2 */
  const void *pKey1, int nKey1,   /* Left side of comparison */
  const void *pKey2, int nKey2    /* Right side of comparison */
){
  UnpackedRecord *r2 = pTask->pUnpacked;
  if( *pbKey2Cached==0 ){
    sqlite3VdbeRecordUnpack(pTask->pSorter->pKeyInfo, nKey2, pKey2, r2);
    *pbKey2Cached = 1;
  }
  return sqlite3VdbeRecordCompareWithSkip(nKey1, pKey1, r2, 1);
}

/*
** Compare key1 (buffer pKey1, size nKey1 bytes) with key2 (buffer pKey2, 
** size nKey2 bytes). Use (pTask->pKeyInfo) for the collation sequences
** used by the comparison. Return the result of the comparison.
**
** If IN/OUT parameter *pbKey2Cached is true when this function is called,
** it is assumed that (pTask->pUnpacked) contains the unpacked version
** Before returning, object (pTask->pUnpacked) is populated with the
** unpacked version of key2. Or, if pKey2 is passed a NULL pointer, then it 
** of key2. If it is false, (pTask->pUnpacked) is populated with the unpacked
** version of key2 and *pbKey2Cached set to true before returning.
** is assumed that the (pTask->pUnpacked) structure already contains the 
** unpacked key to use as key2.
**
** If an OOM error is encountered, (pTask->pUnpacked->error_rc) is set
** to SQLITE_NOMEM.
*/
static int vdbeSorterCompare(
  SortSubtask *pTask,             /* Subtask context (for pKeyInfo) */
  int *pbKey2Cached,              /* True if pTask->pUnpacked is pKey2 */
  const void *pKey1, int nKey1,   /* Left side of comparison */
  const void *pKey2, int nKey2    /* Right side of comparison */
){
  UnpackedRecord *r2 = pTask->pUnpacked;
  if( pKey2 ){
  if( !*pbKey2Cached ){
    sqlite3VdbeRecordUnpack(pTask->pSorter->pKeyInfo, nKey2, pKey2, r2);
    *pbKey2Cached = 1;
  }
  return sqlite3VdbeRecordCompare(nKey1, pKey1, r2);
}

/*
** A specially optimized version of vdbeSorterCompare() that assumes that
** the first field of each key is a TEXT value and that the collation
** sequence to compare them with is BINARY.
*/
static int vdbeSorterCompareText(
  SortSubtask *pTask,             /* Subtask context (for pKeyInfo) */
  int *pbKey2Cached,              /* True if pTask->pUnpacked is pKey2 */
  const void *pKey1, int nKey1,   /* Left side of comparison */
  const void *pKey2, int nKey2    /* Right side of comparison */
){
  const u8 * const p1 = (const u8 * const)pKey1;
  const u8 * const p2 = (const u8 * const)pKey2;
  const u8 * const v1 = &p1[ p1[0] ];   /* Pointer to value 1 */
  const u8 * const v2 = &p2[ p2[0] ];   /* Pointer to value 2 */

  int n1;
  int n2;
  int res;

  getVarint32(&p1[1], n1); n1 = (n1 - 13) / 2;
  getVarint32(&p2[1], n2); n2 = (n2 - 13) / 2;
  res = memcmp(v1, v2, MIN(n1, n2));
  if( res==0 ){
    res = n1 - n2;
  }

  if( res==0 ){
    if( pTask->pSorter->pKeyInfo->nField>1 ){
      res = vdbeSorterCompareTail(
          pTask, pbKey2Cached, pKey1, nKey1, pKey2, nKey2
      );
    }
  }else{
    if( pTask->pSorter->pKeyInfo->aSortOrder[0] ){
      res = res * -1;
    }
  }

  return res;
}

/*
** A specially optimized version of vdbeSorterCompare() that assumes that
** the first field of each key is an INTEGER value.
*/
static int vdbeSorterCompareInt(
  SortSubtask *pTask,             /* Subtask context (for pKeyInfo) */
  int *pbKey2Cached,              /* True if pTask->pUnpacked is pKey2 */
  const void *pKey1, int nKey1,   /* Left side of comparison */
  const void *pKey2, int nKey2    /* Right side of comparison */
){
  const u8 * const p1 = (const u8 * const)pKey1;
  const u8 * const p2 = (const u8 * const)pKey2;
  const int s1 = p1[1];                 /* Left hand serial type */
  const int s2 = p2[1];                 /* Right hand serial type */
  const u8 * const v1 = &p1[ p1[0] ];   /* Pointer to value 1 */
  const u8 * const v2 = &p2[ p2[0] ];   /* Pointer to value 2 */
  int res;                              /* Return value */

  assert( (s1>0 && s1<7) || s1==8 || s1==9 );
  assert( (s2>0 && s2<7) || s2==8 || s2==9 );

  if( s1>7 && s2>7 ){
    res = s1 - s2;
  }else{
    if( s1==s2 ){
      if( (*v1 ^ *v2) & 0x80 ){
        /* The two values have different signs */
        res = (*v1 & 0x80) ? -1 : +1;
      }else{
        /* The two values have the same sign. Compare using memcmp(). */
        static const u8 aLen[] = {0, 1, 2, 3, 4, 6, 8 };
        int i;
        res = 0;
        for(i=0; i<aLen[s1]; i++){
          if( (res = v1[i] - v2[i]) ) break;
        }
      }
    }else{
      if( s2>7 ){
        res = +1;
      }else if( s1>7 ){
        res = -1;
      }else{
        res = s1 - s2;
      }

      if( res>0 ){
        if( *v1 & 0x80 ) res = -1;
      }else if( res<0 ){
        if( *v2 & 0x80 ) res = +1;
      }
    }
  }

  if( res==0 ){
    if( pTask->pSorter->pKeyInfo->nField>1 ){
      res = vdbeSorterCompareTail(
          pTask, pbKey2Cached, pKey1, nKey1, pKey2, nKey2
      );
    }
  }else if( pTask->pSorter->pKeyInfo->aSortOrder[0] ){
    res = res * -1;
  }

  return res;
}

/*
** Initialize the temporary index cursor just opened as a sorter cursor.
**
** Usually, the sorter module uses the value of (pCsr->pKeyInfo->nField)
** to determine the number of fields that should be compared from the
** records being sorted. However, if the value passed as argument nField

  pCsr->pSorter = pSorter;
  if( pSorter==0 ){
    rc = SQLITE_NOMEM;
  }else{
    pSorter->pKeyInfo = pKeyInfo = (KeyInfo*)((u8*)pSorter + sz);
    memcpy(pKeyInfo, pCsr->pKeyInfo, szKeyInfo);
    pKeyInfo->db = 0;
    if( nField && nWorker==0 ) pKeyInfo->nField = nField;
    if( nField && nWorker==0 ){
      pKeyInfo->nXField += (pKeyInfo->nField - nField);
      pKeyInfo->nField = nField;
    }
    pSorter->pgsz = pgsz = sqlite3BtreeGetPageSize(db->aDb[0].pBt);
    pSorter->nTask = nWorker + 1;
    pSorter->iPrev = nWorker-1;
    pSorter->bUseThreads = (pSorter->nTask>1);
    pSorter->db = db;
    for(i=0; i<pSorter->nTask; i++){
      SortSubtask *pTask = &pSorter->aTask[i];
      pTask->pSorter = pSorter;
    }

      if( sqlite3GlobalConfig.pScratch==0 ){
        assert( pSorter->iMemory==0 );
        pSorter->nMemory = pgsz;
        pSorter->list.aMemory = (u8*)sqlite3Malloc(pgsz);
        if( !pSorter->list.aMemory ) rc = SQLITE_NOMEM;
      }
    }

    if( (pKeyInfo->nField+pKeyInfo->nXField)<13 
     && (pKeyInfo->aColl[0]==0 || pKeyInfo->aColl[0]==db->pDfltColl)
    ){
      pSorter->typeMask = SORTER_TYPE_INTEGER | SORTER_TYPE_TEXT;
    }
  }

  return rc;
}
#undef nWorker   /* Defined at the top of this function */

/*

  SortSubtask *pTask,             /* Calling thread context */
  SorterRecord *p1,               /* First list to merge */
  SorterRecord *p2,               /* Second list to merge */
  SorterRecord **ppOut            /* OUT: Head of merged list */
){
  SorterRecord *pFinal = 0;
  SorterRecord **pp = &pFinal;
  void *pVal2 = p2 ? SRVAL(p2) : 0;
  int bCached = 0;

  while( p1 && p2 ){
    int res;
    res = pTask->xCompare(
    res = vdbeSorterCompare(pTask, SRVAL(p1), p1->nVal, pVal2, p2->nVal);
        pTask, &bCached, SRVAL(p1), p1->nVal, SRVAL(p2), p2->nVal
    );

    if( res<=0 ){
      *pp = p1;
      pp = &p1->u.pNext;
      p1 = p1->u.pNext;
      pVal2 = 0;
    }else{
      *pp = p2;
       pp = &p2->u.pNext;
      pp = &p2->u.pNext;
      p2 = p2->u.pNext;
      if( p2==0 ) break;
      pVal2 = SRVAL(p2);
      bCached = 0;
    }
  }
  *pp = p1 ? p1 : p2;
  *ppOut = pFinal;
}

/*
** Return the SorterCompare function to compare values collected by the
** sorter object passed as the only argument.
*/
static SorterCompare vdbeSorterGetCompare(VdbeSorter *p){
  if( p->typeMask==SORTER_TYPE_INTEGER ){
    return vdbeSorterCompareInt;
  }else if( p->typeMask==SORTER_TYPE_TEXT ){
    return vdbeSorterCompareText; 
  }
  return vdbeSorterCompare;
}

/*
** Sort the linked list of records headed at pTask->pList. Return 
** SQLITE_OK if successful, or an SQLite error code (i.e. SQLITE_NOMEM) if 
** an error occurs.
*/
static int vdbeSorterSort(SortSubtask *pTask, SorterList *pList){
  int i;
  SorterRecord **aSlot;
  SorterRecord *p;
  int rc;

  rc = vdbeSortAllocUnpacked(pTask);
  if( rc!=SQLITE_OK ) return rc;

  p = pList->pList;
  pTask->xCompare = vdbeSorterGetCompare(pTask->pSorter);

  aSlot = (SorterRecord **)sqlite3MallocZero(64 * sizeof(SorterRecord *));
  if( !aSlot ){
    return SQLITE_NOMEM;
  }

  p = pList->pList;
  while( p ){
    SorterRecord *pNext;
    if( pList->aMemory ){
      if( (u8*)p==pList->aMemory ){
        pNext = 0;
      }else{
        assert( p->u.iNext<sqlite3MallocSize(pList->aMemory) );

  rc = vdbePmaReaderNext(&pMerger->aReadr[iPrev]);

  /* Update contents of aTree[] */
  if( rc==SQLITE_OK ){
    int i;                      /* Index of aTree[] to recalculate */
    PmaReader *pReadr1;         /* First PmaReader to compare */
    PmaReader *pReadr2;         /* Second PmaReader to compare */
    u8 *pKey2;                  /* To pReadr2->aKey, or 0 if record cached */
    int bCached = 0;

    /* Find the first two PmaReaders to compare. The one that was just
    ** advanced (iPrev) and the one next to it in the array.  */
    pReadr1 = &pMerger->aReadr[(iPrev & 0xFFFE)];
    pReadr2 = &pMerger->aReadr[(iPrev | 0x0001)];
    pKey2 = pReadr2->aKey;

    for(i=(pMerger->nTree+iPrev)/2; i>0; i=i/2){
      /* Compare pReadr1 and pReadr2. Store the result in variable iRes. */
      int iRes;
      if( pReadr1->pFd==0 ){
        iRes = +1;
      }else if( pReadr2->pFd==0 ){
        iRes = -1;
      }else{
        iRes = vdbeSorterCompare(pTask, 
            pReadr1->aKey, pReadr1->nKey, pKey2, pReadr2->nKey
        iRes = pTask->xCompare(pTask, &bCached,
            pReadr1->aKey, pReadr1->nKey, pReadr2->aKey, pReadr2->nKey
        );
      }

      /* If pReadr1 contained the smaller value, set aTree[i] to its index.
      ** Then set pReadr2 to the next PmaReader to compare to pReadr1. In this
      ** case there is no cache of pReadr2 in pTask->pUnpacked, so set
      ** pKey2 to point to the record belonging to pReadr2.

      ** If the two values were equal, then the value from the oldest
      ** PMA should be considered smaller. The VdbeSorter.aReadr[] array
      ** is sorted from oldest to newest, so pReadr1 contains older values
      ** than pReadr2 iff (pReadr1<pReadr2).  */
      if( iRes<0 || (iRes==0 && pReadr1<pReadr2) ){
        pMerger->aTree[i] = (int)(pReadr1 - pMerger->aReadr);
        pReadr2 = &pMerger->aReadr[ pMerger->aTree[i ^ 0x0001] ];
        pKey2 = pReadr2->aKey;
        bCached = 0;
      }else{
        if( pReadr1->pFd ) pKey2 = 0;
        if( pReadr1->pFd ) bCached = 0;
        pMerger->aTree[i] = (int)(pReadr2 - pMerger->aReadr);
        pReadr1 = &pMerger->aReadr[ pMerger->aTree[i ^ 0x0001] ];
      }
    }
    *pbEof = (pMerger->aReadr[pMerger->aTree[1]].pFd==0);
  }

  VdbeSorter *pSorter = pCsr->pSorter;
  int rc = SQLITE_OK;             /* Return Code */
  SorterRecord *pNew;             /* New list element */

  int bFlush;                     /* True to flush contents of memory to PMA */
  int nReq;                       /* Bytes of memory required */
  int nPMA;                       /* Bytes of PMA space required */
  int t;                          /* serial type of first record field */

  getVarint32((const u8*)&pVal->z[1], t);
  if( t>0 && t<10 && t!=7 ){
    pSorter->typeMask &= SORTER_TYPE_INTEGER;
  }else if( t>10 && (t & 0x01) ){
    pSorter->typeMask &= SORTER_TYPE_TEXT;
  }else{
    pSorter->typeMask = 0;
  }

  assert( pSorter );

  /* Figure out whether or not the current contents of memory should be
  ** flushed to a PMA before continuing. If so, do so.
  **
  ** If using the single large allocation mode (pSorter->aMemory!=0), then

  p2 = &pMerger->aReadr[i2];

  if( p1->pFd==0 ){
    iRes = i2;
  }else if( p2->pFd==0 ){
    iRes = i1;
  }else{
    SortSubtask *pTask = pMerger->pTask;
    int bCached = 0;
    int res;
    assert( pMerger->pTask->pUnpacked!=0 );  /* from vdbeSortSubtaskMain() */
    res = vdbeSorterCompare(
        pMerger->pTask, p1->aKey, p1->nKey, p2->aKey, p2->nKey
    assert( pTask->pUnpacked!=0 );  /* from vdbeSortSubtaskMain() */
    res = pTask->xCompare(
        pTask, &bCached, p1->aKey, p1->nKey, p2->aKey, p2->nKey
    );
    if( res<=0 ){
      iRes = i1;
    }else{
      iRes = i2;
    }
  }

*/
static int vdbeSorterSetupMerge(VdbeSorter *pSorter){
  int rc;                         /* Return code */
  SortSubtask *pTask0 = &pSorter->aTask[0];
  MergeEngine *pMain = 0;
#if SQLITE_MAX_WORKER_THREADS
  sqlite3 *db = pTask0->pSorter->db;
  int i;
  SorterCompare xCompare = vdbeSorterGetCompare(pSorter);
  for(i=0; i<pSorter->nTask; i++){
    pSorter->aTask[i].xCompare = xCompare;
  }
#endif

  rc = vdbeSorterMergeTreeBuild(pSorter, &pMain);
  if( rc==SQLITE_OK ){
#if SQLITE_MAX_WORKER_THREADS
    assert( pSorter->bUseThreads==0 || pSorter->nTask>1 );
    if( pSorter->bUseThreads ){

  db transaction {
    execsql { PRAGMA page_size = 1024; }
    execsql $sql
    execsql {
      CREATE TABLE t1(a PRIMARY KEY, b UNIQUE);
      INSERT INTO t1 VALUES(1, randomblob(400));
      INSERT INTO t1 SELECT a+1,  randomblob(400) FROM t1;
      INSERT INTO t1 SELECT a+2,  randomblob(400) FROM t1;
      INSERT INTO t1 SELECT a+4,  randomblob(400) FROM t1;
      INSERT INTO t1 SELECT a+8,  randomblob(400) FROM t1;
      INSERT INTO t1 SELECT a+16, randomblob(400) FROM t1;
      INSERT INTO t1 SELECT a+32, randomblob(400) FROM t1;
      INSERT INTO t1 SELECT a+64, randomblob(400) FROM t1;
      INSERT OR FAIL INTO t1 SELECT a+1,  randomblob(400) FROM t1;
      INSERT OR FAIL INTO t1 SELECT a+2,  randomblob(400) FROM t1;
      INSERT OR FAIL INTO t1 SELECT a+4,  randomblob(400) FROM t1;
      INSERT OR FAIL INTO t1 SELECT a+8,  randomblob(400) FROM t1;
      INSERT OR FAIL INTO t1 SELECT a+16, randomblob(400) FROM t1;
      INSERT OR FAIL INTO t1 SELECT a+32, randomblob(400) FROM t1;
      INSERT OR FAIL INTO t1 SELECT a+64, randomblob(400) FROM t1;

      CREATE TABLE t2(a PRIMARY KEY, b UNIQUE);
      INSERT INTO t2 SELECT * FROM t1;
      INSERT OR FAIL INTO t2 SELECT * FROM t1;
    }
  }

  return [expr {[file size test.db] / 1024}]
}

# This proc returns the number of contiguous blocks of pages that make up

#                    less fragmented.
#
ifcapable vtab&&compound {
  create_db 
  register_dbstat_vtab db
  do_execsql_test e_vacuum-1.2.1 {
    DELETE FROM t1 WHERE a%2;
    INSERT INTO t1 SELECT b, a FROM t2 WHERE a%2;
    INSERT OR REPLACE INTO t1 SELECT b, a FROM t2 WHERE a%2;
    UPDATE t1 SET b=randomblob(600) WHERE (a%2)==0;
  } {}
  
  do_test e_vacuum-1.2.2.1 { expr [fragment_count t1]>100 } 1
  do_test e_vacuum-1.2.2.2 { expr [fragment_count sqlite_autoindex_t1_1]>100 } 1
  do_test e_vacuum-1.2.2.3 { expr [fragment_count sqlite_autoindex_t1_2]>100 } 1
  

# 2015 March 20
#
# 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.
#
#***********************************************************************
#
# The tests in this file ensure that sorter objects are used by 
# "INSERT INTO ... SELECT ..." statements when possible.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix insert6

# Return the number of OP_SorterOpen instructions in the SQL passed as
# the only argument if it is compiled using connection [db].
#
proc sorter_count {sql} {
  set res 0
  db cache flush
  db eval "EXPLAIN $sql" x {
    if {$x(opcode) == "SorterOpen"} { incr res }
  }
  return $res
}


#-------------------------------------------------------------------------
# Warm body test. This verifies that the simplest case works for both
# regular and WITHOUT ROWID tables.
#
do_execsql_test 1.1 {
  CREATE TABLE t2(x UNIQUE ON CONFLICT IGNORE, y, z);
  WITH cnt(x) AS ( SELECT 0 UNION ALL SELECT x+1 FROM cnt WHERE x<99 )
  INSERT INTO t2 SELECT abs(random()), abs(random()), abs(random()) FROM cnt;
}

foreach {tn nSort schema} {
  1 3 { CREATE TABLE t1(a, b, c) }
  2 4 { CREATE TABLE t1(a PRIMARY KEY, b, c) WITHOUT ROWID }
} {

  do_test 1.$tn.1 {
    execsql { DROP TABLE IF EXISTS t1 }
    execsql $schema 
  } {}

  do_execsql_test 1.$tn.2 {
    CREATE INDEX t1a ON t1(a);
    CREATE INDEX t1b ON t1(b);
    CREATE INDEX t1c ON t1(c);
  }

  do_execsql_test 1.$tn.3 {
    INSERT INTO t1 SELECT x, y, z FROM t2;
    PRAGMA integrity_check;
    SELECT count(*) FROM t1;
  } {ok 100}
  
  do_execsql_test 1.$tn.4 {
    INSERT INTO t1 SELECT -x, y, z FROM t2;
    PRAGMA integrity_check;
  } {ok}

  do_execsql_test 1.$tn.5 {
    SELECT count(*) FROM t1;
  } {200}

  do_test 1.$tn.6 {
    sorter_count { INSERT INTO t1 SELECT * FROM t2 }
  } $nSort
}

#-------------------------------------------------------------------------
# The following test cases check that the sorters are disabled if any
# of the following are true:
#
#   2.1: The statement specifies "ON CONFLICT FAIL", "IGNORE" or "REPLACE".
#
#   2.2: The statement does not explicitly specify a conflict mode and 
#        there are one or more PRIMARY KEY or UNIQUE constraints with 
#        "OR FAIL", "OR IGNORE" or "OR REPLACE" as the conflict handling 
#        mode.
#
#   2.3: There are one or more INSERT triggers on the target table.
#
#   2.4: The target table is the parent or child of an FK constraint.
#

do_execsql_test 2.1.1 {
  CREATE TABLE x1(a, b, c);
  CREATE INDEX x1a ON x1(a);

  CREATE TABLE x2(a, b, c);
  CREATE UNIQUE INDEX x2a ON x2(a);

  CREATE TABLE x3(a PRIMARY KEY, b, c);
  CREATE TABLE x4(a PRIMARY KEY, b, c) WITHOUT ROWID;
}

do_test 2.1.2 { sorter_count { INSERT OR REPLACE INTO x1 SELECT * FROM t2 } } 0
do_test 2.1.3 { sorter_count { INSERT OR REPLACE INTO x2 SELECT * FROM t2 } } 0
do_test 2.1.4 { sorter_count { INSERT OR REPLACE INTO x3 SELECT * FROM t2 } } 0
do_test 2.1.5 { sorter_count { INSERT OR REPLACE INTO x4 SELECT * FROM t2 } } 0

do_test 2.1.6 { sorter_count { INSERT OR IGNORE INTO x1 SELECT * FROM t2 } } 0
do_test 2.1.7 { sorter_count { INSERT OR IGNORE INTO x2 SELECT * FROM t2 } } 0
do_test 2.1.8 { sorter_count { INSERT OR IGNORE INTO x3 SELECT * FROM t2 } } 0
do_test 2.1.9 { sorter_count { INSERT OR IGNORE INTO x4 SELECT * FROM t2 } } 0

do_test 2.1.10 { sorter_count { INSERT OR FAIL INTO x1 SELECT * FROM t2 } } 0
do_test 2.1.11 { sorter_count { INSERT OR FAIL INTO x2 SELECT * FROM t2 } } 0
do_test 2.1.12 { sorter_count { INSERT OR FAIL INTO x3 SELECT * FROM t2 } } 0
do_test 2.1.13 { sorter_count { INSERT OR FAIL INTO x4 SELECT * FROM t2 } } 0

do_test 2.1.14 { sorter_count { INSERT OR ROLLBACK INTO x1 SELECT * FROM t2} } 1
do_test 2.1.15 { sorter_count { INSERT OR ROLLBACK INTO x2 SELECT * FROM t2} } 1
do_test 2.1.16 { sorter_count { INSERT OR ROLLBACK INTO x3 SELECT * FROM t2} } 1
do_test 2.1.17 { sorter_count { INSERT OR ROLLBACK INTO x4 SELECT * FROM t2} } 1

do_test 2.1.18 { sorter_count { INSERT OR ABORT INTO x1 SELECT * FROM t2 } } 1
do_test 2.1.19 { sorter_count { INSERT OR ABORT INTO x2 SELECT * FROM t2 } } 1
do_test 2.1.20 { sorter_count { INSERT OR ABORT INTO x3 SELECT * FROM t2 } } 1
do_test 2.1.21 { sorter_count { INSERT OR ABORT INTO x4 SELECT * FROM t2 } } 1


foreach {tn scount schema} {
  2.1   0 { CREATE TABLE t1(a UNIQUE ON CONFLICT FAIL, b, c) }
  2.2   0 { CREATE TABLE t1(a, b UNIQUE ON CONFLICT IGNORE, c) }
  2.3   0 { CREATE TABLE t1(a, b, c UNIQUE ON CONFLICT REPLACE) }
  2.4   0 { CREATE TABLE t1(a PRIMARY KEY ON CONFLICT FAIL, b, c) }
  2.5   0 { CREATE TABLE t1(a, b PRIMARY KEY ON CONFLICT IGNORE, c) }
  2.6   0 { CREATE TABLE t1(a, b, c PRIMARY KEY ON CONFLICT REPLACE) }
  2.7   0 { 
    CREATE TABLE t1(a PRIMARY KEY ON CONFLICT FAIL, b, c) WITHOUT ROWID
  }
  2.8   0 { 
    CREATE TABLE t1(a, b PRIMARY KEY ON CONFLICT IGNORE, c) WITHOUT ROWID
  }
  2.9   0 { 
    CREATE TABLE t1(a, b, c PRIMARY KEY ON CONFLICT REPLACE) WITHOUT ROWID
  }

  3.1   1 {
    CREATE TABLE t1(a, b, c);
    CREATE INDEX i1 ON t1(a);
  }
  3.2   0 {
    CREATE TABLE t1(a, b, c);
    CREATE INDEX i1 ON t1(a);
    CREATE TRIGGER tr1 AFTER INSERT ON t1 BEGIN SELECT 1; END;
  }
  3.3   0 {
    CREATE TABLE t1(a, b, c);
    CREATE INDEX i1 ON t1(a);
    CREATE TRIGGER tr2 BEFORE INSERT ON t1 BEGIN SELECT 1; END;
  }

  4.1   2 {
    CREATE TABLE t1(a PRIMARY KEY, b, c);
    CREATE INDEX i1 ON t1(a);
    CREATE TABLE c1(x, y REFERENCES t1 DEFERRABLE INITIALLY DEFERRED);
    PRAGMA foreign_keys = 0;
  }
  4.2   0 {
    CREATE TABLE t1(a PRIMARY KEY, b, c);
    CREATE INDEX i1 ON t1(a);
    CREATE TABLE c1(x, y REFERENCES t1 DEFERRABLE INITIALLY DEFERRED);
    PRAGMA foreign_keys = 1;
  }

  4.3   1 {
    CREATE TABLE p1(x, y UNIQUE);
    CREATE TABLE t1(a, b, c REFERENCES p1(y));
    CREATE INDEX i1 ON t1(a);
    PRAGMA foreign_keys = 0;
  }
  4.4   0 {
    CREATE TABLE p1(x, y UNIQUE);
    CREATE TABLE t1(a, b, c REFERENCES p1(y));
    CREATE INDEX i1 ON t1(a);
    PRAGMA foreign_keys = 1;
  }

} {
  execsql { 
    DROP TABLE IF EXISTS t1;
    DROP TABLE IF EXISTS c1;
    DROP TABLE IF EXISTS p1;
  }

  do_test 2.2.$tn {
    execsql $schema
    sorter_count { INSERT INTO t1 SELECT * FROM t2 }
  } $scount
}

#-------------------------------------------------------------------------
# Test that if a UNIQUE constraint is violated and the on conflict mode
# is either ABORT or ROLLBACK, the conflict is handled correctly.
#
#   3.2: Check that conflicts are actually detected. 
#   3.3: Check that OR ROLLBACK really does rollback the transaction.
#   3.4: Check that OR ABORT does not.
#
do_execsql_test 3.1 {
  DROP TABLE IF EXISTS t1;
  CREATE TABLE t1(a PRIMARY KEY, b, c, UNIQUE(b, c));
  INSERT INTO t1 VALUES(1, 2, 3);
  INSERT INTO t1 VALUES(4, 5, 6);
  INSERT INTO t1 VALUES(7, 8, 9);
  CREATE TABLE src(a, b, c);
}

do_catchsql_test 3.2.1 {
  INSERT INTO src VALUES (10, 11, 12), (7, 14, 12);
  INSERT INTO t1 SELECT * FROM src;
} {1 {UNIQUE constraint failed: t1.a}}

do_catchsql_test 3.2.2 {
  DELETE FROM src;
  INSERT INTO src VALUES (10, 11, 12), (13, 5, 6);
  INSERT INTO t1 SELECT * FROM src;
} {1 {UNIQUE constraint failed: t1.b, t1.c}}

do_catchsql_test 3.2.3.1 {
  CREATE TABLE t3(a);
  CREATE UNIQUE INDEX t3a ON t3(a);

  CREATE TABLE t3src(a);
  WITH cnt(x) AS ( SELECT 0 UNION ALL SELECT x+1 FROM cnt WHERE x<10 )
  INSERT INTO t3src SELECT 'abc' FROM cnt;
} {0 {}}

#  execsql { PRAGMA vdbe_trace = 1 }
do_catchsql_test 3.2.3.2 {
  INSERT INTO t3 SELECT * FROM t3src;
} {1 {UNIQUE constraint failed: t3.a}}

do_catchsql_test 3.3.1 {
  DELETE FROM src;
  BEGIN;
    INSERT INTO src VALUES (10, 11, 12), (7, 13, 14);
    INSERT OR ROLLBACK INTO t1 SELECT * FROM src;
} {1 {UNIQUE constraint failed: t1.a}}
do_catchsql_test 3.3.2 {
  DELETE FROM src;
  BEGIN;
    INSERT INTO src VALUES (10, 11, 12), (13, 5, 6);
    INSERT OR ROLLBACK INTO t1 SELECT * FROM src;
} {1 {UNIQUE constraint failed: t1.b, t1.c}}
do_test 3.3.3 {
  sqlite3_get_autocommit db
} 1

do_catchsql_test 3.4.1 {
  DELETE FROM src;
  BEGIN;
    INSERT INTO src VALUES (10, 11, 12), (7, 14, 12);
    INSERT OR ABORT INTO t1 SELECT * FROM src;
} {1 {UNIQUE constraint failed: t1.a}}
do_catchsql_test 3.4.2 {
  ROLLBACK;
  DELETE FROM src;
  BEGIN;
    INSERT INTO src VALUES (10, 11, 12), (13, 5, 6);
    INSERT OR ABORT INTO t1 SELECT * FROM src;
} {1 {UNIQUE constraint failed: t1.b, t1.c}}
do_test 3.4.3 {
  sqlite3_get_autocommit db
} 0
do_execsql_test 3.4.4 { ROLLBACK }

#-------------------------------------------------------------------------
# The following tests - 4.* - check that this optimization is actually
# doing something helpful. They do this by executing a big 
# "INSERT INTO SELECT" statement in wal mode with a small pager cache.
# Once with "OR FAIL" (so that the sorters are not used) and once with
# the default "OR ABORT" (so that they are).
#
# If the sorters are doing their job, the wal file generated by the 
# "OR ABORT" case should be much smaller than the "OR FAIL" trial.
#

proc odd_collate {lhs rhs} {
  string compare [string range $lhs 6 end] [string range $rhs 6 end]
}

proc do_insert6_4_test {tn sql} {

  reset_db
  db collate odd_collate odd_collate
  execsql $sql
  db_save_and_close

  foreach {tn2 ::onerror ::var} {
    1 "OR ABORT" ::sz1
    2 "OR FAIL"  ::sz2
  } {
    do_test $tn.$tn2 {
      db_restore_and_reopen
      db collate odd_collate odd_collate
      execsql "
        PRAGMA journal_mode = wal;
        PRAGMA cache_size = 5;
        PRAGMA wal_autocheckpoint = 0;
        INSERT $onerror INTO t1 SELECT * FROM src;
      "
      set $var [file size test.db-wal]
      db close
    } {}
  }

  do_test $tn.3.($::sz1<$::sz2) {
    expr {$sz1 < ($sz2/2)}
  } 1

  sqlite3 db test.db
  db collate odd_collate odd_collate
  integrity_check $tn.4 
}

do_insert6_4_test 4.1 {
  CREATE TABLE t1(a, b, c);
  CREATE UNIQUE INDEX t1a ON t1(a);
  CREATE UNIQUE INDEX t1bc ON t1(b, c);

  CREATE TABLE src(x, y, z);
  WITH cnt(x) AS ( SELECT 0 UNION ALL SELECT x+1 FROM cnt WHERE x<2999 )
  INSERT INTO src 
  SELECT randomblob(50), randomblob(50), randomblob(50) FROM cnt;
}

do_insert6_4_test 4.2 {
  CREATE TABLE t1(a INTEGER PRIMARY KEY, b, x);
  CREATE UNIQUE INDEX t1b ON t1(b);
  CREATE INDEX t1x1 ON t1(x);
  CREATE INDEX t1x2 ON t1(x);
  CREATE INDEX t1x3 ON t1(x);
  CREATE INDEX t1x4 ON t1(x);

  CREATE TABLE src(a, b, x);
  WITH cnt(x) AS ( SELECT 0 UNION ALL SELECT x+1 FROM cnt WHERE x<2999 )
  INSERT INTO src 
  SELECT random(), x, zeroblob(50) FROM cnt;
}

do_insert6_4_test 4.3 {
  CREATE TABLE t1(a, b, c);
  CREATE UNIQUE INDEX t1ab ON t1(a, b);
  CREATE UNIQUE INDEX t1ac ON t1(a, c);

  CREATE TABLE src(a, b, c);
  WITH cnt(x) AS ( SELECT 0 UNION ALL SELECT x+1 FROM cnt WHERE x<2999 )
  INSERT INTO src 
  SELECT zeroblob(50), randomblob(50), randomblob(50) FROM cnt;
}

db collate odd_collate odd_collate
do_insert6_4_test 4.5 {
  CREATE TABLE t1(t COLLATE odd_collate, v COLLATE odd_collate);
  CREATE UNIQUE INDEX t1t ON t1(t);
  CREATE UNIQUE INDEX t1v ON t1(v);

  CREATE TABLE src(t, v);
  WITH cnt(x) AS ( SELECT 0 UNION ALL SELECT x+1 FROM cnt WHERE x<2999 )
  INSERT INTO src 
  SELECT hex(randomblob(50)), hex(randomblob(50)) FROM cnt;
}

db collate odd_collate odd_collate
do_insert6_4_test 4.6 {
  CREATE TABLE t1(t COLLATE odd_collate PRIMARY KEY) WITHOUT ROWID;
  CREATE TABLE src(t);
  WITH cnt(x) AS ( SELECT 0 UNION ALL SELECT x+1 FROM cnt WHERE x<2999 )
  INSERT INTO src 
  SELECT hex(randomblob(50)) FROM cnt;
}

#-------------------------------------------------------------------------
# At one point the sorters were used for INSERT statements that specify
# "OR FAIL", "REPLACE" or "IGNORE" if there were no PRIMARY KEY or
# UNIQUE indexes. This is incorrect, as all such tables have an implicit
# IPK column. So using the sorters can cause corruption. This test checks
# that that problem no longer exists.
#
reset_db
do_execsql_test 5.1 {
  CREATE TABLE t1(a INTEGER PRIMARY KEY, b, c);
  CREATE INDEX t1b ON t1(b);
  INSERT INTO t1 VALUES(1, 2, 3);
  INSERT INTO t1 VALUES(4, 5, 6);
}

do_catchsql_test 5.2 {
  INSERT OR FAIL INTO t1 
  SELECT 2, 'x', 'x' UNION ALL SELECT 3, 'x', 'x' UNION ALL SELECT 4, 'x', 'x';
} {1 {UNIQUE constraint failed: t1.a}}

integrity_check 5.3


finish_test

    DROP TABLE t1;
  }
} {}

do_execsql_test stat-2.1 {
  CREATE TABLE t3(a PRIMARY KEY, b);
  INSERT INTO t3(rowid, a, b) VALUES(2, a_string(111), a_string(222));
  INSERT INTO t3 SELECT a_string(110+rowid), a_string(221+rowid) FROM t3
  INSERT OR FAIL INTO t3 SELECT a_string(110+rowid), a_string(221+rowid) FROM t3
   ORDER BY rowid;
  INSERT INTO t3 SELECT a_string(110+rowid), a_string(221+rowid) FROM t3
  INSERT OR FAIL INTO t3 SELECT a_string(110+rowid), a_string(221+rowid) FROM t3
   ORDER BY rowid;
  INSERT INTO t3 SELECT a_string(110+rowid), a_string(221+rowid) FROM t3
  INSERT OR FAIL INTO t3 SELECT a_string(110+rowid), a_string(221+rowid) FROM t3
   ORDER BY rowid;
  INSERT INTO t3 SELECT a_string(110+rowid), a_string(221+rowid) FROM t3
  INSERT OR FAIL INTO t3 SELECT a_string(110+rowid), a_string(221+rowid) FROM t3
   ORDER BY rowid;
  INSERT INTO t3 SELECT a_string(110+rowid), a_string(221+rowid) FROM t3
  INSERT OR FAIL INTO t3 SELECT a_string(110+rowid), a_string(221+rowid) FROM t3
   ORDER BY rowid;
  SELECT name, path, pageno, pagetype, ncell, payload, unused, mx_payload
    FROM stat WHERE name != 'sqlite_master';
} [list \
  sqlite_autoindex_t3_1 / 3 internal 3 368 623 125       \
  sqlite_autoindex_t3_1 /000/ 8 leaf 8 946 46 123        \
  sqlite_autoindex_t3_1 /001/ 9 leaf 8 988 2 131         \

  execsql { INSERT INTO t1 VALUES( blob(900) ) }
  list [expr [file size test.db]/1024] [file size test.db-wal]
} [list 3 [wal_file_size 4 1024]]

do_test wal-11.4 {
  execsql { 
    BEGIN;
      INSERT INTO t1 SELECT blob(900) FROM t1;   -- 2
      INSERT INTO t1 SELECT blob(900) FROM t1;   -- 4
      INSERT INTO t1 SELECT blob(900) FROM t1;   -- 8
      INSERT INTO t1 SELECT blob(900) FROM t1;   -- 16
      INSERT OR FAIL INTO t1 SELECT blob(900) FROM t1;   -- 2
      INSERT OR FAIL INTO t1 SELECT blob(900) FROM t1;   -- 4
      INSERT OR FAIL INTO t1 SELECT blob(900) FROM t1;   -- 8
      INSERT OR FAIL INTO t1 SELECT blob(900) FROM t1;   -- 16
  }
  list [expr [file size test.db]/1024] [file size test.db-wal]
} [list 3 [wal_file_size 32 1024]]
do_test wal-11.5 {
  execsql { 
    SELECT count(*) FROM t1;
    PRAGMA integrity_check;

set nWal 39
if {[permutation]!="mmap"} {set nWal 37}
ifcapable !mmap {set nWal 37}
do_test wal-11.10 {
  execsql {
    PRAGMA cache_size = 10;
    BEGIN;
      INSERT INTO t1 SELECT blob(900) FROM t1;   -- 32
      INSERT OR FAIL INTO t1 SELECT blob(900) FROM t1;   -- 32
      SELECT count(*) FROM t1;
  }
  list [expr [file size test.db]/1024] [file size test.db-wal]
} [list 37 [wal_file_size $nWal 1024]]
do_test wal-11.11 {
  execsql {
      SELECT count(*) FROM t1;