pParse->cookieMask = 0;
  pParse->cookieGoto = 0;
}

/*
** Find an available table number for database iDb
*/
static int firstAvailableTableNumber(sqlite4 *db, int iDb){




  HashElem *i;
  int maxTab = 1;
  for(i=sqliteHashFirst(&db->aDb[iDb].pSchema->tblHash); i;i=sqliteHashNext(i)){
    Table *pTab = (Table*)sqliteHashData(i);
    if( pTab->tnum > maxTab ) maxTab = pTab->tnum;
  }
  for(i=sqliteHashFirst(&db->aDb[iDb].pSchema->idxHash); i;i=sqliteHashNext(i)){
    Index *pIdx = (Index*)sqliteHashData(i);
    if( pIdx->tnum > maxTab ) maxTab = pIdx->tnum;
  }








  return maxTab+1;
}

/*
** Run the parser and code generator recursively in order to generate
** code for the SQL statement given onto the end of the pParse context
** currently under construction.  When the parser is run recursively
................................................................................
  ** and allocate the record number for the table entry now.  Before any
  ** PRIMARY KEY or UNIQUE keywords are parsed.  Those keywords will cause
  ** indices to be created and the table record must come before the 
  ** indices.  Hence, the record number for the table must be allocated
  ** now.
  */
  if( !db->init.busy && (v = sqlite4GetVdbe(pParse))!=0 ){
    int reg1, reg2, reg3;
    sqlite4BeginWriteOperation(pParse, 0, iDb);

#ifndef SQLITE_OMIT_VIRTUALTABLE
    if( isVirtual ){
      sqlite4VdbeAddOp0(v, OP_VBegin);
    }
#endif
................................................................................
    **
    ** The rowid for the new entry is left in register pParse->regRowid.
    ** The root page number of the new table is left in reg pParse->regRoot.
    ** The rowid and root page number values are needed by the code that
    ** sqlite4EndTable will generate.
    */
    reg1 = pParse->regRowid = ++pParse->nMem;
    reg2 = pParse->regRoot = ++pParse->nMem;
    reg3 = ++pParse->nMem;

#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
    if( isView || isVirtual ){
      sqlite4VdbeAddOp2(v, OP_Integer, 0, reg2);
    }else
#endif
    {
      int tnum = firstAvailableTableNumber(db, iDb);
      sqlite4VdbeAddOp2(v, OP_Integer, tnum, reg2);
    }

    sqlite4OpenMasterTable(pParse, iDb);
    sqlite4VdbeAddOp2(v, OP_NewRowid, 0, reg1);
    sqlite4VdbeAddOp2(v, OP_Null, 0, reg3);
    sqlite4VdbeAddOp3(v, OP_Insert, 0, reg3, reg1);
    sqlite4VdbeChangeP5(v, OPFLAG_APPEND);
    sqlite4VdbeAddOp0(v, OP_Close);
  }
................................................................................
  Parse *pParse,    /* Parsing context */
  ExprList *pList,  /* List of field names to be indexed */
  int onError,      /* What to do with a uniqueness conflict */
  int autoInc,      /* True if the AUTOINCREMENT keyword is present */
  int sortOrder     /* SQLITE_SO_ASC or SQLITE_SO_DESC */
){
  Table *pTab = pParse->pNewTable;

  char *zType = 0;

  int iCol = -1, i;
  if( pTab==0 || IN_DECLARE_VTAB ) goto primary_key_exit;
  if( pTab->tabFlags & TF_HasPrimaryKey ){
    sqlite4ErrorMsg(pParse, 
      "table \"%s\" has more than one primary key", pTab->zName);
    goto primary_key_exit;
  }
................................................................................
      }
      if( iCol<pTab->nCol ){
        pTab->aCol[iCol].isPrimKey = 1;
      }
    }
    if( pList->nExpr>1 ) iCol = -1;
  }


  if( iCol>=0 && iCol<pTab->nCol ){
    zType = pTab->aCol[iCol].zType;
  }

  if( zType && sqlite4StrICmp(zType, "INTEGER")==0
        && sortOrder==SQLITE_SO_ASC ){
    pTab->iPKey = iCol;
    pTab->keyConf = (u8)onError;
    assert( autoInc==0 || autoInc==1 );
    pTab->tabFlags |= autoInc*TF_Autoincrement;
  }else if( autoInc ){
#ifndef SQLITE_OMIT_AUTOINCREMENT
    sqlite4ErrorMsg(pParse, "AUTOINCREMENT is only allowed on an "
       "INTEGER PRIMARY KEY");
#endif
  }else{



    Index *p;

    p = sqlite4CreateIndex(pParse, 0, 0, 0, pList, onError, 0, 0, sortOrder, 0);
    if( p ){
      p->autoIndex = 2;
    }

    pList = 0;
  }

primary_key_exit:
  sqlite4ExprListDelete(pParse->db, pList);
  return;
}
................................................................................
    memcpy(&zStmt[k], zType, len);
    k += len;
    assert( k<=n );
  }
  sqlite4_snprintf(n-k, &zStmt[k], "%s", zEnd);
  return zStmt;
}




































































































/*
** This routine is called to report the final ")" that terminates
** a CREATE TABLE statement.
**
** The table structure that other action routines have been building
** is added to the internal hash tables, assuming no errors have
................................................................................
  Token *pCons,           /* The ',' token after the last column defn. */
  Token *pEnd,            /* The final ')' token in the CREATE TABLE */
  Select *pSelect         /* Select from a "CREATE ... AS SELECT" */
){
  Table *p;
  sqlite4 *db = pParse->db;
  int iDb;



  if( (pEnd==0 && pSelect==0) || db->mallocFailed ){
    return;
  }
  p = pParse->pNewTable;
  if( p==0 ) return;

  assert( !db->init.busy || !pSelect );

  iDb = sqlite4SchemaToIndex(db, p->pSchema);












#ifndef SQLITE_OMIT_CHECK
  /* Resolve names in all CHECK constraint expressions.
  */
  if( p->pCheck ){
    SrcList sSrc;                   /* Fake SrcList for pParse->pNewTable */
    NameContext sNC;                /* Name context for pParse->pNewTable */
................................................................................
    sNC.isCheck = 1;
    if( sqlite4ResolveExprNames(&sNC, p->pCheck) ){
      return;
    }
  }
#endif /* !defined(SQLITE_OMIT_CHECK) */

  /* If the db->init.busy is 1 it means we are reading the SQL off the
  ** "sqlite_master" or "sqlite_temp_master" table on the disk.
  ** So do not write to the disk again.  Extract the root page number
  ** for the table from the db->init.newTnum field.  (The page number
  ** should have been put there by the sqliteOpenCb routine.)
  */
  if( db->init.busy ){
    p->tnum = db->init.newTnum;
  }

  /* If not initializing, then create a record for the new table
  ** in the SQLITE_MASTER table of the database.
  **
  ** If this is a TEMPORARY table, write the entry into the auxiliary
  ** file instead of into the main database file.
  */
  if( !db->init.busy ){
................................................................................
    ** be redundant.
    */
    if( pSelect ){
      SelectDest dest;
      Table *pSelTab;

      assert(pParse->nTab==1);
      sqlite4VdbeAddOp3(v, OP_OpenWrite, 1, pParse->regRoot, iDb);
      sqlite4VdbeChangeP5(v, 1);
      pParse->nTab = 2;
      sqlite4SelectDestInit(&dest, SRT_Table, 1);
      sqlite4Select(pParse, pSelect, &dest);
      sqlite4VdbeAddOp1(v, OP_Close, 1);
      if( pParse->nErr==0 ){
        pSelTab = sqlite4ResultSetOfSelect(pParse, pSelect);
        if( pSelTab==0 ) return;
................................................................................

    /* A slot for the record has already been allocated in the 
    ** SQLITE_MASTER table.  We just need to update that slot with all
    ** the information we've collected.
    */
    sqlite4NestedParse(pParse,
      "UPDATE %Q.%s "
         "SET type='%s', name=%Q, tbl_name=%Q, rootpage=#%d, sql=%Q "
       "WHERE rowid=#%d",
      db->aDb[iDb].zName, SCHEMA_TABLE(iDb),
      zType,
      p->zName,
      p->zName,
      pParse->regRoot,
      zStmt,
      pParse->regRowid
    );
    sqlite4DbFree(db, zStmt);
    sqlite4ChangeCookie(pParse, iDb);

#ifndef SQLITE_OMIT_AUTOINCREMENT
................................................................................
** Code to update the sqlite_master tables and internal schema definitions
** in case a root-page belonging to another table is moved by the btree layer
** is also added (this can happen with an auto-vacuum database).
*/
static void destroyTable(Parse *pParse, Table *pTab){
  Index *pIdx;
  int iDb = sqlite4SchemaToIndex(pParse->db, pTab->pSchema);
  destroyRootPage(pParse, pTab->tnum, iDb);
  for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
    destroyRootPage(pParse, pIdx->tnum, iDb);
  }
}

/*
** Remove entries from the sqlite_statN tables (for N in (1,2,3))
................................................................................
  sqlite4VdbeAddOp4(v, OP_SorterOpen, iSorter, 0, 0, (char*)pKey, P4_KEYINFO);
#else
  iSorter = iTab;
#endif

  /* Open the table. Loop through all rows of the table, inserting index
  ** records into the sorter. */
  sqlite4OpenTable(pParse, iTab, iDb, pTab, OP_OpenRead);
  addr1 = sqlite4VdbeAddOp2(v, OP_Rewind, iTab, 0);
  regRecord = sqlite4GetTempRange(pParse,2);

#ifndef SQLITE_OMIT_MERGE_SORT
  sqlite4GenerateIndexKey(pParse, pIndex, iTab, regRecord, 1, iIdx);
  sqlite4VdbeAddOp2(v, OP_SorterInsert, iSorter, regRecord);
  sqlite4VdbeAddOp2(v, OP_Next, iTab, addr1+1);
................................................................................
  Token *pName2,     /* Second part of index name. May be NULL */
  SrcList *pTblName, /* Table to index. Use pParse->pNewTable if 0 */
  ExprList *pList,   /* A list of columns to be indexed */
  int onError,       /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
  Token *pStart,     /* The CREATE token that begins this statement */
  Token *pEnd,       /* The ")" that closes the CREATE INDEX statement */
  int sortOrder,     /* Sort order of primary key when pList==NULL */
  int ifNotExist     /* Omit error if index already exists */

){
  Index *pRet = 0;     /* Pointer to return */
  Table *pTab = 0;     /* Table to be indexed */
  Index *pIndex = 0;   /* The index to be created */
  char *zName = 0;     /* Name of the index */
  int nName;           /* Number of characters in zName */
  int i, j;
  Token nullId;        /* Fake token for an empty ID list */
  DbFixer sFix;        /* For assigning database names to pTable */
  int sortOrderMask;   /* 1 to honor DESC in index.  0 to ignore. */
  sqlite4 *db = pParse->db;
  Db *pDb;             /* The specific table containing the indexed database */
  int iDb;             /* Index of the database that is being written */
  Token *pName = 0;    /* Unqualified name of the index to create */
  struct ExprList_item *pListItem; /* For looping over pList */
  int nCol;
  int nExtra = 0;
  char *zExtra;

  assert( pStart==0 || pEnd!=0 ); /* pEnd must be non-NULL if pStart is */
  assert( pParse->nErr==0 );      /* Never called with prior errors */
  if( db->mallocFailed || IN_DECLARE_VTAB ){
    goto exit_create_index;
................................................................................
  */
  if( pTblName!=0 ){

    /* Use the two-part index name to determine the database 
    ** to search for the table. 'Fix' the table name to this db
    ** before looking up the table.
    */

    assert( pName1 && pName2 );
    iDb = sqlite4TwoPartName(pParse, pName1, pName2, &pName);
    if( iDb<0 ) goto exit_create_index;
    assert( pName && pName->z );

#ifndef SQLITE_OMIT_TEMPDB
    /* If the index name was unqualified, check if the the table
................................................................................
    if( !pTab ) goto exit_create_index;
    iDb = sqlite4SchemaToIndex(db, pTab->pSchema);
  }
  pDb = &db->aDb[iDb];

  assert( pTab!=0 );
  assert( pParse->nErr==0 );




  if( sqlite4StrNICmp(pTab->zName, "sqlite_", 7)==0 
       && memcmp(&pTab->zName[7],"altertab_",9)!=0 ){
    sqlite4ErrorMsg(pParse, "table %s may not be indexed", pTab->zName);
    goto exit_create_index;
  }


#ifndef SQLITE_OMIT_VIEW
  if( pTab->pSelect ){

    sqlite4ErrorMsg(pParse, "views may not be indexed");
    goto exit_create_index;
  }
#endif
#ifndef SQLITE_OMIT_VIRTUALTABLE
  if( IsVirtual(pTab) ){

    sqlite4ErrorMsg(pParse, "virtual tables may not be indexed");
    goto exit_create_index;
  }
#endif

  /*
  ** Find the name of the index.  Make sure there is not already another
................................................................................
  ** index, then we will continue to process this index.
  **
  ** If pName==0 it means that we are
  ** dealing with a primary key or UNIQUE constraint.  We have to invent our
  ** own name.
  */
  if( pName ){

    zName = sqlite4NameFromToken(db, pName);
    if( zName==0 ) goto exit_create_index;
    assert( pName->z!=0 );
    if( SQLITE_OK!=sqlite4CheckObjectName(pParse, zName) ){
      goto exit_create_index;
    }
    if( !db->init.busy ){
................................................................................
        sqlite4ErrorMsg(pParse, "index %s already exists", zName);
      }else{
        assert( !db->init.busy );
        sqlite4CodeVerifySchema(pParse, iDb);
      }
      goto exit_create_index;
    }
  }else{
    int n;
    Index *pLoop;
    for(pLoop=pTab->pIndex, n=1; pLoop; pLoop=pLoop->pNext, n++){}
    zName = sqlite4MPrintf(db, "sqlite_autoindex_%s_%d", pTab->zName, n);



    if( zName==0 ){
      goto exit_create_index;
    }
  }

  /* Check for authorization to create an index.
  */
#ifndef SQLITE_OMIT_AUTHORIZATION
  {
    const char *zDb = pDb->zName;
    if( sqlite4AuthCheck(pParse, SQLITE_INSERT, SCHEMA_TABLE(iDb), 0, zDb) ){
      goto exit_create_index;
    }
    i = SQLITE_CREATE_INDEX;
    if( !OMIT_TEMPDB && iDb==1 ) i = SQLITE_CREATE_TEMP_INDEX;
    if( sqlite4AuthCheck(pParse, i, zName, pTab->zName, zDb) ){
      goto exit_create_index;
    }
  }
#endif

  /* If pList==0, it means this routine was called to make a primary
  ** key out of the last column added to the table under construction.
  ** So create a fake list to simulate this.



  */
  if( pList==0 ){
    nullId.z = pTab->aCol[pTab->nCol-1].zName;
    nullId.n = sqlite4Strlen30((char*)nullId.z);
    pList = sqlite4ExprListAppend(pParse, 0, 0);
    if( pList==0 ) goto exit_create_index;
    sqlite4ExprListSetName(pParse, pList, &nullId, 0);
................................................................................
      ** failure we have quit before reaching this point. */
      if( ALWAYS(pColl) ){
        nExtra += (1 + sqlite4Strlen30(pColl->zName));
      }
    }
  }

  /* 
  ** Allocate the index structure. 
  */
  nName = sqlite4Strlen30(zName);
  nCol = pList->nExpr;
  pIndex = sqlite4DbMallocZero(db, 
      ROUND8(sizeof(Index)) +              /* Index structure  */
      ROUND8(sizeof(tRowcnt)*(nCol+1)) +   /* Index.aiRowEst   */
      sizeof(char *)*nCol +                /* Index.azColl     */
      sizeof(int)*nCol +                   /* Index.aiColumn   */
      sizeof(u8)*nCol +                    /* Index.aSortOrder */
      nName + 1 +                          /* Index.zName      */
      nExtra                               /* Collation sequence names */
  );
  if( db->mallocFailed ){
    goto exit_create_index;
  }
  zExtra = (char*)pIndex;
  pIndex->aiRowEst = (tRowcnt*)&zExtra[ROUND8(sizeof(Index))];
  pIndex->azColl = (char**)
     ((char*)pIndex->aiRowEst + ROUND8(sizeof(tRowcnt)*nCol+1));
  assert( EIGHT_BYTE_ALIGNMENT(pIndex->aiRowEst) );
  assert( EIGHT_BYTE_ALIGNMENT(pIndex->azColl) );
  pIndex->aiColumn = (int *)(&pIndex->azColl[nCol]);
  pIndex->aSortOrder = (u8 *)(&pIndex->aiColumn[nCol]);
  pIndex->zName = (char *)(&pIndex->aSortOrder[nCol]);
  zExtra = (char *)(&pIndex->zName[nName+1]);
  memcpy(pIndex->zName, zName, nName+1);
  pIndex->pTable = pTab;
  pIndex->nColumn = pList->nExpr;
  pIndex->onError = (u8)onError;
  pIndex->autoIndex = (u8)(pName==0);
  pIndex->pSchema = db->aDb[iDb].pSchema;

  /* Check to see if we should honor DESC requests on index columns
  */
  if( pDb->pSchema->file_format>=4 ){
    sortOrderMask = -1;   /* Honor DESC */
  }else{
    sortOrderMask = 0;    /* Ignore DESC */
................................................................................
    ** the constraint occur in different orders, then the constraints are
    ** considered distinct and both result in separate indices.
    */
    Index *pIdx;
    for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
      int k;
      assert( pIdx->onError!=OE_None );
      assert( pIdx->autoIndex );
      assert( pIndex->onError!=OE_None );

      if( pIdx->nColumn!=pIndex->nColumn ) continue;
      for(k=0; k<pIdx->nColumn; k++){
        const char *z1;
        const char *z2;
        if( pIdx->aiColumn[k]!=pIndex->aiColumn[k] ) break;
................................................................................
    }
  }

  /* Link the new Index structure to its table and to the other
  ** in-memory database structures. 
  */
  if( db->init.busy ){
    Index *p;
    p = sqlite4HashInsert(&pIndex->pSchema->idxHash, 
                          pIndex->zName, sqlite4Strlen30(pIndex->zName),
                          pIndex);
    if( p ){
      assert( p==pIndex );  /* Malloc must have failed */
      db->mallocFailed = 1;
      goto exit_create_index;
    }
    db->flags |= SQLITE_InternChanges;
    if( pTblName!=0 ){
      pIndex->tnum = db->init.newTnum;
    }
  }

  /* If the db->init.busy is 0 then create the index on disk.  This
  ** involves writing the index into the master table and filling in the
  ** index with the current table contents.
................................................................................
  ** we don't want to recreate it.
  **
  ** If pTblName==0 it means this index is generated as a primary key
  ** or UNIQUE constraint of a CREATE TABLE statement.  Since the table
  ** has just been created, it contains no data and the index initialization
  ** step can be skipped.
  */
  else{ /* if( db->init.busy==0 ) */


    Vdbe *v;
    char *zStmt;

    v = sqlite4GetVdbe(pParse);
    if( v==0 ) goto exit_create_index;


    /* Create the rootpage for the index
    */
    sqlite4BeginWriteOperation(pParse, 1, iDb);
    pIndex->tnum = firstAvailableTableNumber(db, iDb);

    /* Gather the complete text of the CREATE INDEX statement into
    ** the zStmt variable
    */
    if( pStart ){
      assert( pEnd!=0 );
      /* A named index with an explicit CREATE INDEX statement */
      zStmt = sqlite4MPrintf(db, "CREATE%s INDEX %.*s",
        onError==OE_None ? "" : " UNIQUE",
        (int)(pEnd->z - pName->z) + 1,
        pName->z);
    }else{
      /* An automatic index created by a PRIMARY KEY or UNIQUE constraint */
      /* zStmt = sqlite4MPrintf(""); */
      zStmt = 0;
    }

    /* Add an entry in sqlite_master for this index
    */
    sqlite4NestedParse(pParse, 
        "INSERT INTO %Q.%s VALUES('index',%Q,%Q,%d,%Q);",
        db->aDb[iDb].zName, SCHEMA_TABLE(iDb),
        pIndex->zName,
        pTab->zName,
        pIndex->tnum,
        zStmt
    );
    sqlite4DbFree(db, zStmt);

    /* Fill the index with data and reparse the schema. Code an OP_Expire
    ** to invalidate all pre-compiled statements.
    */
    if( pTblName ){
      sqlite4RefillIndex(pParse, pIndex);
      sqlite4ChangeCookie(pParse, iDb);
      sqlite4VdbeAddParseSchemaOp(v, iDb,
         sqlite4MPrintf(db, "name='%q' AND type='index'", pIndex->zName));
      sqlite4VdbeAddOp1(v, OP_Expire, 0);

    }
  }

  /* When adding an index to the list of indices for a table, make
  ** sure all indices labeled OE_Replace come after all those labeled
  ** OE_Ignore.  This is necessary for the correct constraint check
  ** processing (in sqlite4GenerateConstraintChecks()) as part of
................................................................................
**
** aiRowEst[0] is suppose to contain the number of elements in the index.
** Since we do not know, guess 1 million.  aiRowEst[1] is an estimate of the
** number of rows in the table that match any particular value of the
** first column of the index.  aiRowEst[2] is an estimate of the number
** of rows that match any particular combiniation of the first 2 columns
** of the index.  And so forth.  It must always be the case that
*
**           aiRowEst[N]<=aiRowEst[N-1]
**           aiRowEst[N]>=1
**
** Apart from that, we have little to go on besides intuition as to
** how aiRowEst[] should be initialized.  The numbers generated here
** are based on typical values found in actual indices.
*/
................................................................................
      sqlite4ErrorMsg(pParse, "no such index: %S", pName, 0);
    }else{
      sqlite4CodeVerifyNamedSchema(pParse, pName->a[0].zDatabase);
    }
    pParse->checkSchema = 1;
    goto exit_drop_index;
  }
  if( pIndex->autoIndex ){
    sqlite4ErrorMsg(pParse, "index associated with UNIQUE "
      "or PRIMARY KEY constraint cannot be dropped", 0);
    goto exit_drop_index;
  }
  iDb = sqlite4SchemaToIndex(db, pIndex->pSchema);
#ifndef SQLITE_OMIT_AUTHORIZATION
  {
................................................................................
** If successful, a pointer to the new structure is returned. In this case
** the caller is responsible for calling sqlite4DbFree(db, ) on the returned 
** pointer. If an error occurs (out of memory or missing collation 
** sequence), NULL is returned and the state of pParse updated to reflect
** the error.
*/
KeyInfo *sqlite4IndexKeyinfo(Parse *pParse, Index *pIdx){

  int i;
  int nCol = pIdx->nColumn;
  int nBytes = sizeof(KeyInfo) + (nCol-1)*sizeof(CollSeq*) + nCol;

  sqlite4 *db = pParse->db;
  KeyInfo *pKey = (KeyInfo *)sqlite4DbMallocZero(db, nBytes);










  if( pKey ){
    pKey->db = pParse->db;
    pKey->aSortOrder = (u8 *)&(pKey->aColl[nCol]);
    assert( &pKey->aSortOrder[nCol]==&(((u8 *)pKey)[nBytes]) );

    for(i=0; i<nCol; i++){
      char *zColl = pIdx->azColl[i];
      assert( zColl );
      pKey->aColl[i] = sqlite4LocateCollSeq(pParse, zColl);
      pKey->aSortOrder[i] = pIdx->aSortOrder[i];
    }









    pKey->nField = (u16)nCol;





  }

  if( pParse->nErr ){
    sqlite4DbFree(db, pKey);
    pKey = 0;
  }
  return pKey;
}

  pParse->cookieMask = 0;
  pParse->cookieGoto = 0;
}

/*
** Find an available table number for database iDb
*/
static int firstAvailableTableNumber(
  sqlite4 *db,                    /* Database handle */
  int iDb,                        /* Index of database in db->aDb[] */
  Table *pTab                     /* New table being constructed */
){
  HashElem *i;
  int maxTab = 1;




  for(i=sqliteHashFirst(&db->aDb[iDb].pSchema->idxHash); i;i=sqliteHashNext(i)){
    Index *pIdx = (Index*)sqliteHashData(i);
    if( pIdx->tnum > maxTab ) maxTab = pIdx->tnum;
  }

  if( pTab ){
    Index *pIdx;
    for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
      if( pIdx->tnum > maxTab ) maxTab = pIdx->tnum;
    }
  }

  return maxTab+1;
}

/*
** Run the parser and code generator recursively in order to generate
** code for the SQL statement given onto the end of the pParse context
** currently under construction.  When the parser is run recursively
................................................................................
  ** and allocate the record number for the table entry now.  Before any
  ** PRIMARY KEY or UNIQUE keywords are parsed.  Those keywords will cause
  ** indices to be created and the table record must come before the 
  ** indices.  Hence, the record number for the table must be allocated
  ** now.
  */
  if( !db->init.busy && (v = sqlite4GetVdbe(pParse))!=0 ){
    int reg1, reg3;
    sqlite4BeginWriteOperation(pParse, 0, iDb);

#ifndef SQLITE_OMIT_VIRTUALTABLE
    if( isVirtual ){
      sqlite4VdbeAddOp0(v, OP_VBegin);
    }
#endif
................................................................................
    **
    ** The rowid for the new entry is left in register pParse->regRowid.
    ** The root page number of the new table is left in reg pParse->regRoot.
    ** The rowid and root page number values are needed by the code that
    ** sqlite4EndTable will generate.
    */
    reg1 = pParse->regRowid = ++pParse->nMem;

    reg3 = ++pParse->nMem;
#if 0
#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
    if( isView || isVirtual ){
      sqlite4VdbeAddOp2(v, OP_Integer, 0, reg2);
    }else
#endif
    {
      int tnum = firstAvailableTableNumber(db, iDb);
      sqlite4VdbeAddOp2(v, OP_Integer, tnum, reg2);
    }
#endif
    sqlite4OpenMasterTable(pParse, iDb);
    sqlite4VdbeAddOp2(v, OP_NewRowid, 0, reg1);
    sqlite4VdbeAddOp2(v, OP_Null, 0, reg3);
    sqlite4VdbeAddOp3(v, OP_Insert, 0, reg3, reg1);
    sqlite4VdbeChangeP5(v, OPFLAG_APPEND);
    sqlite4VdbeAddOp0(v, OP_Close);
  }
................................................................................
  Parse *pParse,    /* Parsing context */
  ExprList *pList,  /* List of field names to be indexed */
  int onError,      /* What to do with a uniqueness conflict */
  int autoInc,      /* True if the AUTOINCREMENT keyword is present */
  int sortOrder     /* SQLITE_SO_ASC or SQLITE_SO_DESC */
){
  Table *pTab = pParse->pNewTable;
#if 0
  char *zType = 0;
#endif
  int iCol = -1, i;
  if( pTab==0 || IN_DECLARE_VTAB ) goto primary_key_exit;
  if( pTab->tabFlags & TF_HasPrimaryKey ){
    sqlite4ErrorMsg(pParse, 
      "table \"%s\" has more than one primary key", pTab->zName);
    goto primary_key_exit;
  }
................................................................................
      }
      if( iCol<pTab->nCol ){
        pTab->aCol[iCol].isPrimKey = 1;
      }
    }
    if( pList->nExpr>1 ) iCol = -1;
  }

#if 0
  if( iCol>=0 && iCol<pTab->nCol ){
    zType = pTab->aCol[iCol].zType;
  }

  if( zType && sqlite4StrICmp(zType, "INTEGER")==0
        && sortOrder==SQLITE_SO_ASC ){
    pTab->iPKey = iCol;
    pTab->keyConf = (u8)onError;
    assert( autoInc==0 || autoInc==1 );
    pTab->tabFlags |= autoInc*TF_Autoincrement;
  }else if( autoInc ){
#ifndef SQLITE_OMIT_AUTOINCREMENT
    sqlite4ErrorMsg(pParse, "AUTOINCREMENT is only allowed on an "
       "INTEGER PRIMARY KEY");
#endif
  }else
#endif

  {
    Index *p;
    p = sqlite4CreateIndex(
        pParse, 0, 0, 0, pList, onError, 0, 0, sortOrder, 0, 1



    );
    pList = 0;
  }

primary_key_exit:
  sqlite4ExprListDelete(pParse->db, pList);
  return;
}
................................................................................
    memcpy(&zStmt[k], zType, len);
    k += len;
    assert( k<=n );
  }
  sqlite4_snprintf(n-k, &zStmt[k], "%s", zEnd);
  return zStmt;
}

static Index *newIndex(
  Parse *pParse,                  /* Parse context for current statement */
  Table *pTab,                    /* Table index is created on */
  const char *zName,              /* Name of index object to create */
  int nCol,                       /* Number of columns in index */
  int onError,                    /* One of OE_Abort, OE_Replace etc. */
  int nExtra,                     /* Bytes of extra space to allocate */
  char **pzExtra                  /* OUT: Pointer to extra space */
){
  sqlite4 *db = pParse->db;       /* Database handle */
  Index *pIndex;                  /* Return value */
  char *zExtra = 0;               /* nExtra bytes of extra space allocated */
  int nName;                      /* Length of zName in bytes */

  /* Allocate the index structure. */
  nName = sqlite4Strlen30(zName);
  pIndex = sqlite4DbMallocZero(db, 
      ROUND8(sizeof(Index)) +              /* Index structure  */
      ROUND8(sizeof(tRowcnt)*(nCol+1)) +   /* Index.aiRowEst   */
      sizeof(char *)*nCol +                /* Index.azColl     */
      sizeof(int)*nCol +                   /* Index.aiColumn   */
      sizeof(u8)*nCol +                    /* Index.aSortOrder */
      nName + 1 +                          /* Index.zName      */
      nExtra                               /* Collation sequence names */
  );
  assert( pIndex || db->mallocFailed );

  if( pIndex ){
    zExtra = (char*)pIndex;
    pIndex->aiRowEst = (tRowcnt*)&zExtra[ROUND8(sizeof(Index))];
    pIndex->azColl = (char**)
      ((char*)pIndex->aiRowEst + ROUND8(sizeof(tRowcnt)*nCol+1));
    assert( EIGHT_BYTE_ALIGNMENT(pIndex->aiRowEst) );
    assert( EIGHT_BYTE_ALIGNMENT(pIndex->azColl) );
    pIndex->aiColumn = (int *)(&pIndex->azColl[nCol]);
    pIndex->aSortOrder = (u8 *)(&pIndex->aiColumn[nCol]);
    pIndex->zName = (char *)(&pIndex->aSortOrder[nCol]);
    zExtra = (char *)(&pIndex->zName[nName+1]);
    memcpy(pIndex->zName, zName, nName+1);
    pIndex->pTable = pTab;
    pIndex->nColumn = nCol;
    pIndex->onError = (u8)onError;
    pIndex->pSchema = pTab->pSchema;

    if( db->init.busy ){
      Hash *pIdxHash = &pIndex->pSchema->idxHash;
      Index *p;

      p = sqlite4HashInsert(pIdxHash, pIndex->zName, nName, pIndex);
      if( p ){
        assert( p==pIndex );
        db->mallocFailed = 1;
        sqlite4DbFree(db, pIndex);
        pIndex = 0;
      }
    }
  }

  *pzExtra = zExtra;
  return pIndex;
}


/*
** Allocate and populate an Index structure representing an implicit 
** primary key. In implicit primary key behaves similarly to the built-in
** INTEGER PRIMARY KEY columns in SQLite 3.
*/
static void addImplicitPrimaryKey(
  Parse *pParse,                  /* Parse context */
  Table *pTab,                    /* Table to add implicit PRIMARY KEY to */
  int iDb
){
  Index *pIndex;                  /* New index */
  char *zExtra;

  assert( !pTab->pIndex || pTab->pIndex->eIndexType!=SQLITE_INDEX_PRIMARYKEY );
  assert( sqlite4Strlen30("binary")==6 );
  pIndex = newIndex(pParse, pTab, pTab->zName, 1, OE_Abort, 1+6, &zExtra);
  if( pIndex ){
    sqlite4 *db = pParse->db;

    pIndex->aiColumn[0] = -1;
    pIndex->azColl[0] = zExtra;
    memcpy(zExtra, "binary", 7);
    pIndex->eIndexType = SQLITE_INDEX_PRIMARYKEY;
    pIndex->pNext = pTab->pIndex;
    pTab->pIndex = pIndex;
    sqlite4DefaultRowEst(pIndex);
    pTab->tabFlags |= TF_HasPrimaryKey;

    if( db->init.busy ){
      pIndex->tnum = db->init.newTnum;
    }else{
      pIndex->tnum = firstAvailableTableNumber(db, iDb, pTab);
    }
  }
}

/*
** This routine is called to report the final ")" that terminates
** a CREATE TABLE statement.
**
** The table structure that other action routines have been building
** is added to the internal hash tables, assuming no errors have
................................................................................
  Token *pCons,           /* The ',' token after the last column defn. */
  Token *pEnd,            /* The final ')' token in the CREATE TABLE */
  Select *pSelect         /* Select from a "CREATE ... AS SELECT" */
){
  Table *p;
  sqlite4 *db = pParse->db;
  int iDb;
  int iPkRoot = 0;                /* Root page of primary key index */
  Index *pPk;                     /* PRIMARY KEY index for table p */

  if( (pEnd==0 && pSelect==0) || db->mallocFailed ){
    return;
  }
  p = pParse->pNewTable;
  if( p==0 ) return;

  assert( !db->init.busy || !pSelect );

  iDb = sqlite4SchemaToIndex(db, p->pSchema);

  if( 0==(p->tabFlags & TF_HasPrimaryKey) ){
    /* If no explicit PRIMARY KEY has been created, add an implicit 
    ** primary key here.  An implicit primary key works the way "rowid" did
    ** in SQLite 3.  */
    addImplicitPrimaryKey(pParse, p, iDb);
  }
  pPk = sqlite4FindPrimaryKey(p, 0);
  assert( pPk || pParse->nErr || db->mallocFailed );
  if( pPk ) iPkRoot = pPk->tnum;


#ifndef SQLITE_OMIT_CHECK
  /* Resolve names in all CHECK constraint expressions.
  */
  if( p->pCheck ){
    SrcList sSrc;                   /* Fake SrcList for pParse->pNewTable */
    NameContext sNC;                /* Name context for pParse->pNewTable */
................................................................................
    sNC.isCheck = 1;
    if( sqlite4ResolveExprNames(&sNC, p->pCheck) ){
      return;
    }
  }
#endif /* !defined(SQLITE_OMIT_CHECK) */











  /* If not initializing, then create a record for the new table
  ** in the SQLITE_MASTER table of the database.
  **
  ** If this is a TEMPORARY table, write the entry into the auxiliary
  ** file instead of into the main database file.
  */
  if( !db->init.busy ){
................................................................................
    ** be redundant.
    */
    if( pSelect ){
      SelectDest dest;
      Table *pSelTab;

      assert(pParse->nTab==1);
      sqlite4VdbeAddOp3(v, OP_OpenWrite, 1, iPkRoot, iDb);

      pParse->nTab = 2;
      sqlite4SelectDestInit(&dest, SRT_Table, 1);
      sqlite4Select(pParse, pSelect, &dest);
      sqlite4VdbeAddOp1(v, OP_Close, 1);
      if( pParse->nErr==0 ){
        pSelTab = sqlite4ResultSetOfSelect(pParse, pSelect);
        if( pSelTab==0 ) return;
................................................................................

    /* A slot for the record has already been allocated in the 
    ** SQLITE_MASTER table.  We just need to update that slot with all
    ** the information we've collected.
    */
    sqlite4NestedParse(pParse,
      "UPDATE %Q.%s "
         "SET type='%s', name=%Q, tbl_name=%Q, rootpage=%d, sql=%Q "
       "WHERE rowid=#%d",
      db->aDb[iDb].zName, SCHEMA_TABLE(iDb),
      zType,
      p->zName,
      p->zName,
      iPkRoot,
      zStmt,
      pParse->regRowid
    );
    sqlite4DbFree(db, zStmt);
    sqlite4ChangeCookie(pParse, iDb);

#ifndef SQLITE_OMIT_AUTOINCREMENT
................................................................................
** Code to update the sqlite_master tables and internal schema definitions
** in case a root-page belonging to another table is moved by the btree layer
** is also added (this can happen with an auto-vacuum database).
*/
static void destroyTable(Parse *pParse, Table *pTab){
  Index *pIdx;
  int iDb = sqlite4SchemaToIndex(pParse->db, pTab->pSchema);

  for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
    destroyRootPage(pParse, pIdx->tnum, iDb);
  }
}

/*
** Remove entries from the sqlite_statN tables (for N in (1,2,3))
................................................................................
  sqlite4VdbeAddOp4(v, OP_SorterOpen, iSorter, 0, 0, (char*)pKey, P4_KEYINFO);
#else
  iSorter = iTab;
#endif

  /* Open the table. Loop through all rows of the table, inserting index
  ** records into the sorter. */
  sqlite4OpenPrimaryKey(pParse, iTab, iDb, pTab, OP_OpenRead);
  addr1 = sqlite4VdbeAddOp2(v, OP_Rewind, iTab, 0);
  regRecord = sqlite4GetTempRange(pParse,2);

#ifndef SQLITE_OMIT_MERGE_SORT
  sqlite4GenerateIndexKey(pParse, pIndex, iTab, regRecord, 1, iIdx);
  sqlite4VdbeAddOp2(v, OP_SorterInsert, iSorter, regRecord);
  sqlite4VdbeAddOp2(v, OP_Next, iTab, addr1+1);
................................................................................
  Token *pName2,     /* Second part of index name. May be NULL */
  SrcList *pTblName, /* Table to index. Use pParse->pNewTable if 0 */
  ExprList *pList,   /* A list of columns to be indexed */
  int onError,       /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
  Token *pStart,     /* The CREATE token that begins this statement */
  Token *pEnd,       /* The ")" that closes the CREATE INDEX statement */
  int sortOrder,     /* Sort order of primary key when pList==NULL */
  int ifNotExist,    /* Omit error if index already exists */
  int bPrimaryKey    /* True to create the tables primary key */
){
  Index *pRet = 0;     /* Pointer to return */
  Table *pTab = 0;     /* Table to be indexed */
  Index *pIndex = 0;   /* The index to be created */
  char *zName = 0;     /* Name of the index */

  int i, j;
  Token nullId;        /* Fake token for an empty ID list */
  DbFixer sFix;        /* For assigning database names to pTable */
  int sortOrderMask;   /* 1 to honor DESC in index.  0 to ignore. */
  sqlite4 *db = pParse->db;
  Db *pDb;             /* The specific table containing the indexed database */
  int iDb;             /* Index of the database that is being written */
  Token *pName = 0;    /* Unqualified name of the index to create */
  struct ExprList_item *pListItem; /* For looping over pList */

  int nExtra = 0;
  char *zExtra;

  assert( pStart==0 || pEnd!=0 ); /* pEnd must be non-NULL if pStart is */
  assert( pParse->nErr==0 );      /* Never called with prior errors */
  if( db->mallocFailed || IN_DECLARE_VTAB ){
    goto exit_create_index;
................................................................................
  */
  if( pTblName!=0 ){

    /* Use the two-part index name to determine the database 
    ** to search for the table. 'Fix' the table name to this db
    ** before looking up the table.
    */
    assert( !bPrimaryKey );
    assert( pName1 && pName2 );
    iDb = sqlite4TwoPartName(pParse, pName1, pName2, &pName);
    if( iDb<0 ) goto exit_create_index;
    assert( pName && pName->z );

#ifndef SQLITE_OMIT_TEMPDB
    /* If the index name was unqualified, check if the the table
................................................................................
    if( !pTab ) goto exit_create_index;
    iDb = sqlite4SchemaToIndex(db, pTab->pSchema);
  }
  pDb = &db->aDb[iDb];

  assert( pTab!=0 );
  assert( pParse->nErr==0 );

  /* TODO: We will need to reinstate this block when sqlite_master is 
  ** modified to use an implicit primary key.  */
#if 0
  if( sqlite4StrNICmp(pTab->zName, "sqlite_", 7)==0 
       && memcmp(&pTab->zName[7],"altertab_",9)!=0 ){
    sqlite4ErrorMsg(pParse, "table %s may not be indexed", pTab->zName);
    goto exit_create_index;
  }
#endif

#ifndef SQLITE_OMIT_VIEW
  if( pTab->pSelect ){
    assert( !bPrimaryKey );
    sqlite4ErrorMsg(pParse, "views may not be indexed");
    goto exit_create_index;
  }
#endif
#ifndef SQLITE_OMIT_VIRTUALTABLE
  if( IsVirtual(pTab) ){
    assert( !bPrimaryKey );
    sqlite4ErrorMsg(pParse, "virtual tables may not be indexed");
    goto exit_create_index;
  }
#endif

  /*
  ** Find the name of the index.  Make sure there is not already another
................................................................................
  ** index, then we will continue to process this index.
  **
  ** If pName==0 it means that we are
  ** dealing with a primary key or UNIQUE constraint.  We have to invent our
  ** own name.
  */
  if( pName ){
    assert( !bPrimaryKey );
    zName = sqlite4NameFromToken(db, pName);
    if( zName==0 ) goto exit_create_index;
    assert( pName->z!=0 );
    if( SQLITE_OK!=sqlite4CheckObjectName(pParse, zName) ){
      goto exit_create_index;
    }
    if( !db->init.busy ){
................................................................................
        sqlite4ErrorMsg(pParse, "index %s already exists", zName);
      }else{
        assert( !db->init.busy );
        sqlite4CodeVerifySchema(pParse, iDb);
      }
      goto exit_create_index;
    }
  }else if( !bPrimaryKey ){
    int n;
    Index *pLoop;
    for(pLoop=pTab->pIndex, n=1; pLoop; pLoop=pLoop->pNext, n++){}
    zName = sqlite4MPrintf(db, "sqlite_autoindex_%s_%d", pTab->zName, n);
  }else{
    zName = sqlite4MPrintf(db, "%s", pTab->zName);
  }
  if( zName==0 ){
    goto exit_create_index;

  }

  /* Check for authorization to create an index.
  */
#ifndef SQLITE_OMIT_AUTHORIZATION
  if( bPrimaryKey==0 ){
    const char *zDb = pDb->zName;
    if( sqlite4AuthCheck(pParse, SQLITE_INSERT, SCHEMA_TABLE(iDb), 0, zDb) ){
      goto exit_create_index;
    }
    i = SQLITE_CREATE_INDEX;
    if( !OMIT_TEMPDB && iDb==1 ) i = SQLITE_CREATE_TEMP_INDEX;
    if( sqlite4AuthCheck(pParse, i, zName, pTab->zName, zDb) ){
      goto exit_create_index;
    }
  }
#endif

  /* If pList==0, it means this routine was called as a result of a PRIMARY
  ** KEY or UNIQUE constraint attached to the last column added to the table 
  ** under construction. So create a fake list to simulate this.
  **
  ** TODO: This 'fake list' could be created by the caller to reduce the
  ** number of parameters passed to this function.
  */
  if( pList==0 ){
    nullId.z = pTab->aCol[pTab->nCol-1].zName;
    nullId.n = sqlite4Strlen30((char*)nullId.z);
    pList = sqlite4ExprListAppend(pParse, 0, 0);
    if( pList==0 ) goto exit_create_index;
    sqlite4ExprListSetName(pParse, pList, &nullId, 0);
................................................................................
      ** failure we have quit before reaching this point. */
      if( ALWAYS(pColl) ){
        nExtra += (1 + sqlite4Strlen30(pColl->zName));
      }
    }
  }

  /* Allocate the new Index structure. */
  pIndex = newIndex(pParse, pTab, zName, pList->nExpr, onError, nExtra,&zExtra);
  if( !pIndex ) goto exit_create_index;

  assert( pIndex->eIndexType==SQLITE_INDEX_USER );
  if( pName==0 ){
    if( bPrimaryKey ){
      pIndex->eIndexType = SQLITE_INDEX_PRIMARYKEY;
    }else{
      pIndex->eIndexType = SQLITE_INDEX_UNIQUE;
    }
  }






















  /* Check to see if we should honor DESC requests on index columns
  */
  if( pDb->pSchema->file_format>=4 ){
    sortOrderMask = -1;   /* Honor DESC */
  }else{
    sortOrderMask = 0;    /* Ignore DESC */
................................................................................
    ** the constraint occur in different orders, then the constraints are
    ** considered distinct and both result in separate indices.
    */
    Index *pIdx;
    for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
      int k;
      assert( pIdx->onError!=OE_None );
      assert( pIdx->eIndexType!=SQLITE_INDEX_USER );
      assert( pIndex->onError!=OE_None );

      if( pIdx->nColumn!=pIndex->nColumn ) continue;
      for(k=0; k<pIdx->nColumn; k++){
        const char *z1;
        const char *z2;
        if( pIdx->aiColumn[k]!=pIndex->aiColumn[k] ) break;
................................................................................
    }
  }

  /* Link the new Index structure to its table and to the other
  ** in-memory database structures. 
  */
  if( db->init.busy ){









    db->flags |= SQLITE_InternChanges;
    if( pTblName!=0 || bPrimaryKey ){
      pIndex->tnum = db->init.newTnum;
    }
  }

  /* If the db->init.busy is 0 then create the index on disk.  This
  ** involves writing the index into the master table and filling in the
  ** index with the current table contents.
................................................................................
  ** we don't want to recreate it.
  **
  ** If pTblName==0 it means this index is generated as a primary key
  ** or UNIQUE constraint of a CREATE TABLE statement.  Since the table
  ** has just been created, it contains no data and the index initialization
  ** step can be skipped.
  */
  else{
    pIndex->tnum = firstAvailableTableNumber(db, iDb, pTab);
    if( bPrimaryKey==0 ){
      Vdbe *v;
      char *zStmt;

      v = sqlite4GetVdbe(pParse);
      if( v==0 ) goto exit_create_index;


      /* Create the rootpage for the index
      */
      sqlite4BeginWriteOperation(pParse, 1, iDb);
      pIndex->tnum = firstAvailableTableNumber(db, iDb, pTab);

      /* Gather the complete text of the CREATE INDEX statement into
       ** the zStmt variable
       */
      if( pStart ){
        assert( pEnd!=0 );
        /* A named index with an explicit CREATE INDEX statement */
        zStmt = sqlite4MPrintf(db, "CREATE%s INDEX %.*s",
            onError==OE_None ? "" : " UNIQUE",
            (int)(pEnd->z - pName->z) + 1,
            pName->z);
      }else{
        /* An automatic index created by a PRIMARY KEY or UNIQUE constraint */
        /* zStmt = sqlite4MPrintf(""); */
        zStmt = 0;
      }

      /* Add an entry in sqlite_master for this index
      */
      sqlite4NestedParse(pParse, 
          "INSERT INTO %Q.%s VALUES('index',%Q,%Q,%d,%Q);",
          db->aDb[iDb].zName, SCHEMA_TABLE(iDb),
          pIndex->zName,
          pTab->zName,
          pIndex->tnum,
          zStmt
          );
      sqlite4DbFree(db, zStmt);

      /* Fill the index with data and reparse the schema. Code an OP_Expire
       ** to invalidate all pre-compiled statements.
       */
      if( pTblName ){
        sqlite4RefillIndex(pParse, pIndex);
        sqlite4ChangeCookie(pParse, iDb);
        sqlite4VdbeAddParseSchemaOp(v, iDb,
            sqlite4MPrintf(db, "name='%q' AND type='index'", pIndex->zName));
        sqlite4VdbeAddOp1(v, OP_Expire, 0);
      }
    }
  }

  /* When adding an index to the list of indices for a table, make
  ** sure all indices labeled OE_Replace come after all those labeled
  ** OE_Ignore.  This is necessary for the correct constraint check
  ** processing (in sqlite4GenerateConstraintChecks()) as part of
................................................................................
**
** aiRowEst[0] is suppose to contain the number of elements in the index.
** Since we do not know, guess 1 million.  aiRowEst[1] is an estimate of the
** number of rows in the table that match any particular value of the
** first column of the index.  aiRowEst[2] is an estimate of the number
** of rows that match any particular combiniation of the first 2 columns
** of the index.  And so forth.  It must always be the case that
**
**           aiRowEst[N]<=aiRowEst[N-1]
**           aiRowEst[N]>=1
**
** Apart from that, we have little to go on besides intuition as to
** how aiRowEst[] should be initialized.  The numbers generated here
** are based on typical values found in actual indices.
*/
................................................................................
      sqlite4ErrorMsg(pParse, "no such index: %S", pName, 0);
    }else{
      sqlite4CodeVerifyNamedSchema(pParse, pName->a[0].zDatabase);
    }
    pParse->checkSchema = 1;
    goto exit_drop_index;
  }
  if( pIndex->eIndexType!=SQLITE_INDEX_USER ){
    sqlite4ErrorMsg(pParse, "index associated with UNIQUE "
      "or PRIMARY KEY constraint cannot be dropped", 0);
    goto exit_drop_index;
  }
  iDb = sqlite4SchemaToIndex(db, pIndex->pSchema);
#ifndef SQLITE_OMIT_AUTHORIZATION
  {
................................................................................
** If successful, a pointer to the new structure is returned. In this case
** the caller is responsible for calling sqlite4DbFree(db, ) on the returned 
** pointer. If an error occurs (out of memory or missing collation 
** sequence), NULL is returned and the state of pParse updated to reflect
** the error.
*/
KeyInfo *sqlite4IndexKeyinfo(Parse *pParse, Index *pIdx){
  Index *pPk;                     /* Primary key index on same table */
  int i;
  int nCol;

  int nBytes;
  sqlite4 *db = pParse->db;
  KeyInfo *pKey;

  if( pIdx->eIndexType==SQLITE_INDEX_PRIMARYKEY ){
    pPk = 0;
  }else{
    pPk = sqlite4FindPrimaryKey(pIdx->pTable, 0);
  }
  nCol = pIdx->nColumn + (pPk ? pPk->nColumn : 0);

  nBytes = sizeof(KeyInfo) + (nCol-1)*sizeof(CollSeq*) + nCol;
  pKey = (KeyInfo *)sqlite4DbMallocZero(db, nBytes);
  if( pKey ){
    pKey->db = pParse->db;
    pKey->aSortOrder = (u8 *)&(pKey->aColl[nCol]);
    assert( &pKey->aSortOrder[nCol]==&(((u8 *)pKey)[nBytes]) );

    for(i=0; i<pIdx->nColumn; i++){
      char *zColl = pIdx->azColl[i];
      assert( zColl );
      pKey->aColl[i] = sqlite4LocateCollSeq(pParse, zColl);
      pKey->aSortOrder[i] = pIdx->aSortOrder[i];
    }
    if( pPk ){
      for(i=0; i<pPk->nColumn; i++){
        char *zColl = pIdx->azColl[i];
        assert( zColl );
        pKey->aColl[i+pIdx->nColumn] = sqlite4LocateCollSeq(pParse, zColl);
        pKey->aSortOrder[i+pIdx->nColumn] = pPk->aSortOrder[i];
      }
    }

    pKey->nField = (u16)nCol;
    if( pIdx->eIndexType==SQLITE_INDEX_PRIMARYKEY ){
      pKey->nData = pIdx->pTable->nCol;
    }else{
      pKey->nPK = pPk->nColumn;
    }
  }

  if( pParse->nErr ){
    sqlite4DbFree(db, pKey);
    pKey = 0;
  }
  return pKey;
}

  Parse *pParse,         /* The parser context */
  SrcList *pTabList,     /* The table from which we should delete things */
  Expr *pWhere           /* The WHERE clause.  May be null */
){
  Vdbe *v;               /* The virtual database engine */
  Table *pTab;           /* The table from which records will be deleted */
  const char *zDb;       /* Name of database holding pTab */
  int end, addr = 0;     /* A couple addresses of generated code */
  int i;                 /* Loop counter */
  WhereInfo *pWInfo;     /* Information about the WHERE clause */
  Index *pIdx;           /* For looping over indices of the table */
  int iCur;              /* VDBE Cursor number for pTab */
  sqlite4 *db;           /* Main database structure */
  AuthContext sContext;  /* Authorization context */
  NameContext sNC;       /* Name context to resolve expressions in */
................................................................................
    goto delete_from_cleanup;
  }
  assert( pTabList->nSrc==1 );

  /* Locate the table which we want to delete.  This table has to be
  ** put in an SrcList structure because some of the subroutines we
  ** will be calling are designed to work with multiple tables and expect
  ** an SrcList* parameter instead of just a Table* parameter.
  */
  pTab = sqlite4SrcListLookup(pParse, pTabList);
  if( pTab==0 )  goto delete_from_cleanup;

  /* Figure out if we have any triggers and if the table being
  ** deleted from is a view
  */
#ifndef SQLITE_OMIT_TRIGGER
  pTrigger = sqlite4TriggersExist(pParse, pTab, TK_DELETE, 0, 0);
  isView = pTab->pSelect!=0;
#else
# define pTrigger 0
# define isView 0
#endif
#ifdef SQLITE_OMIT_VIEW
# undef isView
# define isView 0
#endif

  /* If pTab is really a view, make sure it has been initialized.
  */
  if( sqlite4ViewGetColumnNames(pParse, pTab) ){
    goto delete_from_cleanup;
  }




  if( sqlite4IsReadOnly(pParse, pTab, (pTrigger?1:0)) ){
    goto delete_from_cleanup;
  }



  iDb = sqlite4SchemaToIndex(db, pTab->pSchema);
  assert( iDb<db->nDb );
  zDb = db->aDb[iDb].zName;
  rcauth = sqlite4AuthCheck(pParse, SQLITE_DELETE, pTab->zName, 0, zDb);
  assert( rcauth==SQLITE_OK || rcauth==SQLITE_DENY || rcauth==SQLITE_IGNORE );
  if( rcauth==SQLITE_DENY ){
    goto delete_from_cleanup;
  }
  assert(!isView || pTrigger);

  /* Assign  cursor number to the table and all its indices.
  */
  assert( pTabList->nSrc==1 );
  iCur = pTabList->a[0].iCursor = pParse->nTab++;
  for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
    pParse->nTab++;
  }

  /* Start the view context
................................................................................
  ** It is easier just to erase the whole table. Prior to version 3.6.5,
  ** this optimization caused the row change count (the value returned by 
  ** API function sqlite4_count_changes) to be set incorrectly.  */
  if( rcauth==SQLITE_OK && pWhere==0 && !pTrigger && !IsVirtual(pTab) 
   && 0==sqlite4FkRequired(pParse, pTab, 0, 0)
  ){
    assert( !isView );
    sqlite4VdbeAddOp4(v, OP_Clear, pTab->tnum, iDb, memCnt,
                      pTab->zName, P4_STATIC);
    for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
      assert( pIdx->pSchema==pTab->pSchema );
      sqlite4VdbeAddOp2(v, OP_Clear, pIdx->tnum, iDb);
    }
  }else
#endif /* SQLITE_OMIT_TRUNCATE_OPTIMIZATION */
  /* The usual case: There is a WHERE clause so we have to scan through
  ** the table and pick which records to delete.
  */
  {
    int iRowSet = ++pParse->nMem;   /* Register for rowset of rows to delete */
    int iRowid = ++pParse->nMem;    /* Used for storing rowid values. */
    int regRowid;                   /* Actual register containing rowids */

    /* Collect rowids of every row to be deleted.
    */




    sqlite4VdbeAddOp2(v, OP_Null, 0, iRowSet);

    pWInfo = sqlite4WhereBegin(
        pParse, pTabList, pWhere, 0, 0, WHERE_DUPLICATES_OK
    );
    if( pWInfo==0 ) goto delete_from_cleanup;
    regRowid = sqlite4ExprCodeGetColumn(pParse, pTab, -1, iCur, iRowid);
    sqlite4VdbeAddOp2(v, OP_RowSetAdd, iRowSet, regRowid);
    if( db->flags & SQLITE_CountRows ){
      sqlite4VdbeAddOp2(v, OP_AddImm, memCnt, 1);
    }
    sqlite4WhereEnd(pWInfo);

    /* Delete every item whose key was written to the list during the
    ** database scan.  We have to delete items after the scan is complete
    ** because deleting an item can change the scan order.  */
    end = sqlite4VdbeMakeLabel(v);

    /* Unless this is a view, open cursors for the table we are 
    ** deleting from and all its indices. If this is a view, then the
    ** only effect this statement has is to fire the INSTEAD OF 
    ** triggers.  */

    if( !isView ){
      sqlite4OpenTableAndIndices(pParse, pTab, iCur, OP_OpenWrite);
    }

    addr = sqlite4VdbeAddOp3(v, OP_RowSetRead, iRowSet, end, iRowid);

    /* Delete the row */
#ifndef SQLITE_OMIT_VIRTUALTABLE
    if( IsVirtual(pTab) ){
      const char *pVTab = (const char *)sqlite4GetVTable(db, pTab);
      sqlite4VtabMakeWritable(pParse, pTab);
      sqlite4VdbeAddOp4(v, OP_VUpdate, 0, 1, iRowid, pVTab, P4_VTAB);
      sqlite4VdbeChangeP5(v, OE_Abort);
      sqlite4MayAbort(pParse);
    }else
#endif
    {
      int count = (pParse->nested==0);    /* True to count changes */
      sqlite4GenerateRowDelete(pParse, pTab, iCur, iRowid, count, pTrigger, OE_Default);


    }

    /* End of the delete loop */
    sqlite4VdbeAddOp2(v, OP_Goto, 0, addr);
    sqlite4VdbeResolveLabel(v, end);

    /* Close the cursors open on the table and its indexes. */
    if( !isView && !IsVirtual(pTab) ){
      for(i=1, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
        sqlite4VdbeAddOp2(v, OP_Close, iCur + i, pIdx->tnum);
      }
      sqlite4VdbeAddOp1(v, OP_Close, iCur);
    }
  }

  /* Update the sqlite_sequence table by storing the content of the
  ** maximum rowid counter values recorded while inserting into
  ** autoincrement tables.
  */
  if( pParse->nested==0 && pParse->pTriggerTab==0 ){
................................................................................
**   3.  The record number of the row to be deleted must be stored in
**       memory cell iRowid.
**
** This routine generates code to remove both the table record and all 
** index entries that point to that record.
*/
void sqlite4GenerateRowDelete(
  Parse *pParse,     /* Parsing context */
  Table *pTab,       /* Table containing the row to be deleted */
  int iCur,          /* Cursor number for the table */
  int iRowid,        /* Memory cell that contains the rowid to delete */
  int count,         /* If non-zero, increment the row change counter */
  Trigger *pTrigger, /* List of triggers to (potentially) fire */
  int onconf         /* Default ON CONFLICT policy for triggers */
){
  Vdbe *v = pParse->pVdbe;        /* Vdbe */
  int iOld = 0;                   /* First register in OLD.* array */
  int iLabel;                     /* Label resolved to end of generated code */


  /* Vdbe is guaranteed to have been allocated by this stage. */
  assert( v );



  /* Seek cursor iCur to the row to delete. If this row no longer exists 
  ** (this can happen if a trigger program has already deleted it), do
  ** not attempt to delete it or fire any DELETE triggers.  */
  iLabel = sqlite4VdbeMakeLabel(v);
  sqlite4VdbeAddOp3(v, OP_NotExists, iCur, iLabel, iRowid);
 
  /* If there are any triggers to fire, allocate a range of registers to
  ** use for the old.* references in the triggers.  */

  if( sqlite4FkRequired(pParse, pTab, 0, 0) || pTrigger ){
    u32 mask;                     /* Mask of OLD.* columns in use */
    int iCol;                     /* Iterator used while populating OLD.* */

    /* TODO: Could use temporary registers here. Also could attempt to
    ** avoid copying the contents of the rowid register.  */
    mask = sqlite4TriggerColmask(
................................................................................
    sqlite4VdbeAddOp3(v, OP_NotExists, iCur, iLabel, iRowid);

    /* Do FK processing. This call checks that any FK constraints that
    ** refer to this table (i.e. constraints attached to other tables) 
    ** are not violated by deleting this row.  */
    sqlite4FkCheck(pParse, pTab, iOld, 0);
  }


  /* Delete the index and table entries. Skip this step if pTab is really
  ** a view (in which case the only effect of the DELETE statement is to
  ** fire the INSTEAD OF triggers).  */ 
  if( pTab->pSelect==0 ){
    sqlite4GenerateRowIndexDelete(pParse, pTab, iCur, 0);
    sqlite4VdbeAddOp2(v, OP_Delete, iCur, (count?OPFLAG_NCHANGE:0));
    if( count ){
      sqlite4VdbeChangeP4(v, -1, pTab->zName, P4_TRANSIENT);
    }

  }

  /* 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 deleted. */ 
  sqlite4FkActions(pParse, pTab, 0, iOld);

................................................................................
  );

  /* Jump here if the row had already been deleted before any BEFORE
  ** trigger programs were invoked. Or if a trigger program throws a 
  ** RAISE(IGNORE) exception.  */
  sqlite4VdbeResolveLabel(v, iLabel);
}







































/*
** This routine generates VDBE code that causes the deletion of all
** index entries associated with a single row of a single table.
**
** The VDBE must be in a particular state when this routine is called.
** These are the requirements:
................................................................................
**   2.  Read/write cursors for all indices of pTab must be open as
**       cursor number iCur+i for the i-th index.
**
**   3.  The "iCur" cursor must be pointing to the row that is to be
**       deleted.
*/
void sqlite4GenerateRowIndexDelete(
  Parse *pParse,     /* Parsing and code generating context */
  Table *pTab,       /* Table containing the row to be deleted */
  int iCur,          /* Cursor number for the table */
  int *aRegIdx       /* Only delete if aRegIdx!=0 && aRegIdx[i]>0 */
){



  int i;

  Index *pIdx;
  int r1;




  for(i=1, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
    if( aRegIdx!=0 && aRegIdx[i-1]==0 ) continue;


    r1 = sqlite4GenerateIndexKey(pParse, pIdx, iCur, 0, 0, 0);
    sqlite4VdbeAddOp3(pParse->pVdbe, OP_IdxDelete, iCur+i, r1,pIdx->nColumn+1);





  }





}

/*
** Generate code that will assemble an index key and put it in register
** regOut.  The key with be for index pIdx which is an index on pTab.
** iCur is the index of a cursor open on the pTab table and pointing to
** the entry that needs indexing.

  Parse *pParse,         /* The parser context */
  SrcList *pTabList,     /* The table from which we should delete things */
  Expr *pWhere           /* The WHERE clause.  May be null */
){
  Vdbe *v;               /* The virtual database engine */
  Table *pTab;           /* The table from which records will be deleted */
  const char *zDb;       /* Name of database holding pTab */
  int addr = 0;     /* A couple addresses of generated code */
  int i;                 /* Loop counter */
  WhereInfo *pWInfo;     /* Information about the WHERE clause */
  Index *pIdx;           /* For looping over indices of the table */
  int iCur;              /* VDBE Cursor number for pTab */
  sqlite4 *db;           /* Main database structure */
  AuthContext sContext;  /* Authorization context */
  NameContext sNC;       /* Name context to resolve expressions in */
................................................................................
    goto delete_from_cleanup;
  }
  assert( pTabList->nSrc==1 );

  /* Locate the table which we want to delete.  This table has to be
  ** put in an SrcList structure because some of the subroutines we
  ** will be calling are designed to work with multiple tables and expect
  ** an SrcList* parameter instead of just a Table* parameter.  */

  pTab = sqlite4SrcListLookup(pParse, pTabList);
  if( pTab==0 )  goto delete_from_cleanup;

  /* Figure out if we have any triggers and if the table being
  ** deleted from is a view.  */

#ifndef SQLITE_OMIT_TRIGGER
  pTrigger = sqlite4TriggersExist(pParse, pTab, TK_DELETE, 0, 0);
  isView = pTab->pSelect!=0;
#else
# define pTrigger 0
# define isView 0
#endif
#ifdef SQLITE_OMIT_VIEW
# undef isView
# define isView 0
#endif

  /* If pTab is really a view, make sure it has been initialized. */

  if( sqlite4ViewGetColumnNames(pParse, pTab) ){
    goto delete_from_cleanup;
  }

  /* Check the table is not read-only (e.g. sqlite_master or sqlite_stat).
  ** Also, check that if pTab is really an SQL view, one or more INSTEAD 
  ** OF DELETE triggers have been configured.  */
  if( sqlite4IsReadOnly(pParse, pTab, (pTrigger?1:0)) ){
    goto delete_from_cleanup;
  }
  assert(!isView || pTrigger);

  /* Invoke the authorization callback */
  iDb = sqlite4SchemaToIndex(db, pTab->pSchema);
  assert( iDb<db->nDb );
  zDb = db->aDb[iDb].zName;
  rcauth = sqlite4AuthCheck(pParse, SQLITE_DELETE, pTab->zName, 0, zDb);
  assert( rcauth==SQLITE_OK || rcauth==SQLITE_DENY || rcauth==SQLITE_IGNORE );
  if( rcauth==SQLITE_DENY ){
    goto delete_from_cleanup;
  }


  /* Assign  cursor number to the table and all its indices. */

  assert( pTabList->nSrc==1 );
  iCur = pTabList->a[0].iCursor = pParse->nTab++;
  for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
    pParse->nTab++;
  }

  /* Start the view context
................................................................................
  ** It is easier just to erase the whole table. Prior to version 3.6.5,
  ** this optimization caused the row change count (the value returned by 
  ** API function sqlite4_count_changes) to be set incorrectly.  */
  if( rcauth==SQLITE_OK && pWhere==0 && !pTrigger && !IsVirtual(pTab) 
   && 0==sqlite4FkRequired(pParse, pTab, 0, 0)
  ){
    assert( !isView );


    for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
      assert( pIdx->pSchema==pTab->pSchema );
      sqlite4VdbeAddOp2(v, OP_Clear, pIdx->tnum, iDb);
    }
  }else
#endif /* SQLITE_OMIT_TRUNCATE_OPTIMIZATION */
  /* The usual case: There is a WHERE clause so we have to scan through
  ** the table and pick which records to delete.
  */
  {
    int regSet = ++pParse->nMem;  /* Register for rowset of rows to delete */
    int regKey = ++pParse->nMem;  /* Used for storing row keys */
    int addrTop;                  /* Instruction (KeySetRead) at top of loop */

    /* Query the table for all rows that match the WHERE clause. Store the
    ** PRIMARY KEY for each matching row in the KeySet object in register
    ** regSet. After the scan is complete, the VM will loop through the set 
    ** of keys in the KeySet and delete each row. Rows must be deleted after 
    ** the scan is complete because deleting an item can change the scan 
    ** order.  */
    sqlite4VdbeAddOp2(v, OP_Null, 0, regSet);
    VdbeComment((v, "initialize KeySet"));
    pWInfo = sqlite4WhereBegin(
        pParse, pTabList, pWhere, 0, 0, WHERE_DUPLICATES_OK
    );
    if( pWInfo==0 ) goto delete_from_cleanup;
    sqlite4VdbeAddOp2(v, OP_RowKey, iCur, regKey);
    sqlite4VdbeAddOp2(v, OP_KeySetAdd, regSet, regKey);
    if( db->flags & SQLITE_CountRows ){
      sqlite4VdbeAddOp2(v, OP_AddImm, memCnt, 1);
    }
    sqlite4WhereEnd(pWInfo);






    /* Unless this is a view, open cursors for all indexes on the table



    ** from which we are deleting.  */
    if( !isView ){
      sqlite4OpenAllIndexes(pParse, pTab, iCur, OP_OpenWrite);
    }

    addrTop = sqlite4VdbeAddOp3(v, OP_KeySetRead, regSet, 0, regKey);

    /* Delete the row */
#ifndef SQLITE_OMIT_VIRTUALTABLE
    if( IsVirtual(pTab) ){
      const char *pVTab = (const char *)sqlite4GetVTable(db, pTab);
      sqlite4VtabMakeWritable(pParse, pTab);
      sqlite4VdbeAddOp4(v, OP_VUpdate, 0, 1, iRowid, pVTab, P4_VTAB);
      sqlite4VdbeChangeP5(v, OE_Abort);
      sqlite4MayAbort(pParse);
    }else
#endif
    {
      int count = (pParse->nested==0);    /* True to count changes */
      sqlite4GenerateRowDelete(
          pParse, pTab, iCur, regKey, count, pTrigger, OE_Default
      );
    }

    /* End of the delete loop */
    sqlite4VdbeAddOp2(v, OP_Goto, 0, addrTop);
    sqlite4VdbeJumpHere(v, addrTop);

    /* Close all open cursors */
    sqlite4CloseAllIndexes(pParse, pTab, iCur);





  }

  /* Update the sqlite_sequence table by storing the content of the
  ** maximum rowid counter values recorded while inserting into
  ** autoincrement tables.
  */
  if( pParse->nested==0 && pParse->pTriggerTab==0 ){
................................................................................
**   3.  The record number of the row to be deleted must be stored in
**       memory cell iRowid.
**
** This routine generates code to remove both the table record and all 
** index entries that point to that record.
*/
void sqlite4GenerateRowDelete(
  Parse *pParse,                  /* Parsing context */
  Table *pTab,                    /* Table containing the row to be deleted */
  int baseCur,                    /* Base cursor number */
  int regKey,                     /* Register containing PK of row to delete */
  int bCount,                     /* True to increment the row change counter */
  Trigger *pTrigger,              /* List of triggers to (potentially) fire */
  int onconf                      /* Default ON CONFLICT policy for triggers */
){
  Vdbe *v = pParse->pVdbe;        /* Vdbe */
  int iOld = 0;                   /* First register in OLD.* array */
  int iLabel;                     /* Label resolved to end of generated code */
  int iPk;

  /* Vdbe is guaranteed to have been allocated by this stage. */
  assert( v );

  sqlite4FindPrimaryKey(pTab, &iPk);

  /* Seek cursor iCur to the row to delete. If this row no longer exists 
  ** (this can happen if a trigger program has already deleted it), do
  ** not attempt to delete it or fire any DELETE triggers.  */
  iLabel = sqlite4VdbeMakeLabel(v);
  sqlite4VdbeAddOp4(v, OP_NotFound, baseCur+iPk, iLabel, regKey, 0, P4_INT32);
 
  /* If there are any triggers to fire, allocate a range of registers to
  ** use for the old.* references in the triggers.  */
#if 0
  if( sqlite4FkRequired(pParse, pTab, 0, 0) || pTrigger ){
    u32 mask;                     /* Mask of OLD.* columns in use */
    int iCol;                     /* Iterator used while populating OLD.* */

    /* TODO: Could use temporary registers here. Also could attempt to
    ** avoid copying the contents of the rowid register.  */
    mask = sqlite4TriggerColmask(
................................................................................
    sqlite4VdbeAddOp3(v, OP_NotExists, iCur, iLabel, iRowid);

    /* Do FK processing. This call checks that any FK constraints that
    ** refer to this table (i.e. constraints attached to other tables) 
    ** are not violated by deleting this row.  */
    sqlite4FkCheck(pParse, pTab, iOld, 0);
  }
#endif

  /* Delete the index and table entries. Skip this step if pTab is really
  ** a view (in which case the only effect of the DELETE statement is to
  ** fire the INSTEAD OF triggers).  */ 
  if( pTab->pSelect==0 ){
    sqlite4GenerateRowIndexDelete(pParse, pTab, baseCur, 0);
#if 0
    if( count ){
      sqlite4VdbeChangeP4(v, -1, pTab->zName, P4_TRANSIENT);
    }
#endif
  }

  /* 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 deleted. */ 
  sqlite4FkActions(pParse, pTab, 0, iOld);

................................................................................
  );

  /* Jump here if the row had already been deleted before any BEFORE
  ** trigger programs were invoked. Or if a trigger program throws a 
  ** RAISE(IGNORE) exception.  */
  sqlite4VdbeResolveLabel(v, iLabel);
}

static void generateIndexKey(
  Parse *pParse,
  Index *pPk, int iPkCsr,
  Index *pIdx, int iIdxCsr,
  int regOut
){
  Vdbe *v = pParse->pVdbe;        /* VM to write code to */
  int nTmpReg;                    /* Number of temp registers required */
  int regTmp;                     /* First register in temp array */
  int i;                          /* Iterator variable */

  /* Allocate temp registers */
  assert( pIdx!=pPk );
  nTmpReg = pIdx->nColumn + pPk->nColumn;
  regTmp = sqlite4GetTempRange(pParse, nTmpReg);

  /* Assemble the values for the key in the array of temp registers */
  for(i=0; i<pIdx->nColumn; i++){
    int regVal = regTmp + i;
    sqlite4VdbeAddOp3(v, OP_Column, iPkCsr, pIdx->aiColumn[i], regVal);
  }
  for(i=0; i<pPk->nColumn; i++){
    int iCol = pPk->aiColumn[i];
    int regVal = pIdx->nColumn + regTmp + i;
    if( iCol<0 ){
      sqlite4VdbeAddOp2(v, OP_Rowid, iPkCsr, regVal);
    }else{
      sqlite4VdbeAddOp3(v, OP_Column, iPkCsr, pPk->aiColumn[i], regVal);
    }
  }

  /* Build the index key */
  sqlite4VdbeAddOp3(v, OP_MakeIdxKey, iIdxCsr, regTmp, regOut);

  /* Release temp registers */
  sqlite4ReleaseTempRange(pParse, regTmp, nTmpReg);
}

/*
** This routine generates VDBE code that causes the deletion of all
** index entries associated with a single row of a single table.
**
** The VDBE must be in a particular state when this routine is called.
** These are the requirements:
................................................................................
**   2.  Read/write cursors for all indices of pTab must be open as
**       cursor number iCur+i for the i-th index.
**
**   3.  The "iCur" cursor must be pointing to the row that is to be
**       deleted.
*/
void sqlite4GenerateRowIndexDelete(
  Parse *pParse,                  /* Parsing and code generating context */
  Table *pTab,                    /* Table containing the row to be deleted */
  int baseCur,                    /* Cursor number for the table */
  int *aRegIdx                    /* Only delete if (aRegIdx && aRegIdx[i]>0) */
){
  Vdbe *v = pParse->pVdbe;
  Index *pPk;
  int iPk;
  int i;
  int regKey;
  Index *pIdx;


  regKey = sqlite4GetTempReg(pParse);
  pPk = sqlite4FindPrimaryKey(pTab, &iPk);

  for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){

    if( pIdx!=pPk && (aRegIdx==0 || aRegIdx[i]>0) ){
      int addrNotFound;
      generateIndexKey(pParse, pPk, baseCur+iPk, pIdx, baseCur+i, regKey);

      addrNotFound = sqlite4VdbeAddOp4(v,
          OP_NotFound, baseCur+i, 0, regKey, 0, P4_INT32
      );
      sqlite4VdbeAddOp1(v, OP_Delete, baseCur+i);
      sqlite4VdbeJumpHere(v, addrNotFound);
    }
  }

  sqlite4VdbeAddOp1(v, OP_Delete, baseCur+iPk);

  sqlite4ReleaseTempReg(pParse, regKey);
}

/*
** Generate code that will assemble an index key and put it in register
** regOut.  The key with be for index pIdx which is an index on pTab.
** iCur is the index of a cursor open on the pTab table and pointing to
** the entry that needs indexing.

      ** of columns. If each indexed column corresponds to a foreign key
      ** column of pFKey, then this index is a winner.  */

      if( zKey==0 ){
        /* If zKey is NULL, then this foreign key is implicitly mapped to 
        ** the PRIMARY KEY of table pParent. The PRIMARY KEY index may be 
        ** identified by the test (Index.autoIndex==2).  */
        if( pIdx->autoIndex==2 ){
          if( aiCol ){
            int i;
            for(i=0; i<nCol; i++) aiCol[i] = pFKey->aCol[i].iFrom;
          }
          break;
        }
      }else{

      ** of columns. If each indexed column corresponds to a foreign key
      ** column of pFKey, then this index is a winner.  */

      if( zKey==0 ){
        /* If zKey is NULL, then this foreign key is implicitly mapped to 
        ** the PRIMARY KEY of table pParent. The PRIMARY KEY index may be 
        ** identified by the test (Index.autoIndex==2).  */
        if( pIdx->eIndexType==SQLITE_INDEX_PRIMARYKEY ){
          if( aiCol ){
            int i;
            for(i=0; i<nCol; i++) aiCol[i] = pFKey->aCol[i].iFrom;
          }
          break;
        }
      }else{

void sqlite4OpenTable(
  Parse *p,       /* Generate code into this VDBE */
  int iCur,       /* The cursor number of the table */
  int iDb,        /* The database index in sqlite4.aDb[] */
  Table *pTab,    /* The table to be opened */
  int opcode      /* OP_OpenRead or OP_OpenWrite */
){
  Vdbe *v;
  if( IsVirtual(pTab) ) return;






  v = sqlite4GetVdbe(p);









  assert( opcode==OP_OpenWrite || opcode==OP_OpenRead );
  sqlite4TableLock(p, iDb, pTab->tnum, (opcode==OP_OpenWrite)?1:0, pTab->zName);






  sqlite4VdbeAddOp3(v, opcode, iCur, pTab->tnum, iDb);
  sqlite4VdbeChangeP4(v, -1, SQLITE_INT_TO_PTR(pTab->nCol), P4_INT32);
  VdbeComment((v, "%s", pTab->zName));






















}

/*
** 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 sqlite4DeleteIndex() is called.
*/
const char *sqlite4IndexAffinityStr(Vdbe *v, Index *pIdx){
  if( !pIdx->zColAff ){
    /* The first time a column affinity string for a particular index is
    ** required, it is allocated and populated here. It is then stored as
    ** a member of the Index structure for subsequent use.
    **
    ** The column affinity string will eventually be deleted by
    ** sqliteDeleteIndex() when the Index structure itself is cleaned
    ** up.
    */
    int n;
    Table *pTab = pIdx->pTable;

    sqlite4 *db = sqlite4VdbeDb(v);


















    pIdx->zColAff = (char *)sqlite4DbMallocRaw(0, pIdx->nColumn+2);
    if( !pIdx->zColAff ){

      db->mallocFailed = 1;
      return 0;
    }








    for(n=0; n<pIdx->nColumn; n++){
      pIdx->zColAff[n] = pTab->aCol[pIdx->aiColumn[n]].affinity;


    }
    pIdx->zColAff[n++] = SQLITE_AFF_INTEGER;

    pIdx->zColAff[n] = 0;
  }
 
  return pIdx->zColAff;
}

/*
** Set P4 of the most recently inserted opcode to a column affinity
................................................................................

  for(i=iStartAddr; i<iEnd; i++){
    VdbeOp *pOp = sqlite4VdbeGetOp(v, i);
    assert( pOp!=0 );
    if( pOp->opcode==OP_OpenRead && pOp->p3==iDb ){
      Index *pIndex;
      int tnum = pOp->p2;
      if( tnum==pTab->tnum ){
        return 1;
      }
      for(pIndex=pTab->pIndex; pIndex; pIndex=pIndex->pNext){
        if( tnum==pIndex->tnum ){
          return 1;
        }
      }
    }
#ifndef SQLITE_OMIT_VIRTUALTABLE
................................................................................
  int appendFlag = 0;   /* True if the insert is likely to be an append */

  /* Register allocations */
  int regFromSelect = 0;/* Base register for data coming from SELECT */
  int regAutoinc = 0;   /* Register holding the AUTOINCREMENT counter */
  int regRowCount = 0;  /* Memory cell used for the row counter */
  int regIns;           /* Block of regs holding rowid+data being inserted */
  int regRowid;         /* registers holding insert rowid */
  int regData;          /* register holding first column to insert */
  int regEof = 0;       /* Register recording end of SELECT data */
  int *aRegIdx = 0;     /* One register allocated to each index */








#ifndef SQLITE_OMIT_TRIGGER
  int isView;                 /* True if attempting to insert into a view */
  Trigger *pTrigger;          /* List of triggers on pTab, if required */
  int tmask;                  /* Mask of trigger times */
#endif

................................................................................
  iDb = sqlite4SchemaToIndex(db, pTab->pSchema);
  assert( iDb<db->nDb );
  pDb = &db->aDb[iDb];
  zDb = pDb->zName;
  if( sqlite4AuthCheck(pParse, SQLITE_INSERT, pTab->zName, 0, zDb) ){
    goto insert_cleanup;
  }





  /* Figure out if we have any triggers and if the table being
  ** inserted into is a view
  */
#ifndef SQLITE_OMIT_TRIGGER
  pTrigger = sqlite4TriggersExist(pParse, pTab, TK_INSERT, 0, &tmask);
  isView = pTab->pSelect!=0;
................................................................................
# undef isView
# define isView 0
#endif
  assert( (pTrigger && tmask) || (pTrigger==0 && tmask==0) );

  /* If pTab is really a view, make sure it has been initialized.
  ** ViewGetColumnNames() is a no-op if pTab is not a view (or virtual 
  ** module table).
  */
  if( sqlite4ViewGetColumnNames(pParse, pTab) ){
    goto insert_cleanup;
  }

  /* Ensure that:
  *  (a) the table is not read-only, 
  *  (b) that if it is a view then ON INSERT triggers exist
  */
  if( sqlite4IsReadOnly(pParse, pTab, tmask) ){
    goto insert_cleanup;
  }

  /* Allocate a VDBE
  */
  v = sqlite4GetVdbe(pParse);
  if( v==0 ) goto insert_cleanup;
  if( pParse->nested==0 ) sqlite4VdbeCountChanges(v);
  sqlite4BeginWriteOperation(pParse, pSelect || pTrigger, iDb);

#ifndef SQLITE_OMIT_XFER_OPT
  /* If the statement is of the form
................................................................................
  if( pColumn==0 && xferOptimization(pParse, pTab, pSelect, onError, iDb) ){
    assert( !pTrigger );
    assert( pList==0 );
    goto insert_end;
  }
#endif /* SQLITE_OMIT_XFER_OPT */

  /* If this is an AUTOINCREMENT table, look up the sequence number in the
  ** sqlite_sequence table and store it in memory cell regAutoinc.
  */
  regAutoinc = autoIncBegin(pParse, iDb, pTab);

  /* Figure out how many columns of data are supplied.  If the data
  ** is coming from a SELECT statement, then generate a co-routine that
  ** produces a single row of the SELECT on each invocation.  The
  ** co-routine is the common header to the 3rd and 4th templates.
  */
  if( pSelect ){
    /* Data is coming from a SELECT.  Generate code to implement that SELECT
................................................................................
      **         if EOF goto M
      **         insert row from R..R+n into temp table
      **         goto L
      **      M: ...
      */
      int regRec;          /* Register to hold packed record */
      int regTempRowid;    /* Register to hold temp table ROWID */

      int addrTop;         /* Label "L" */
      int addrIf;          /* Address of jump to M */

      srcTab = pParse->nTab++;
      regRec = sqlite4GetTempReg(pParse);
      regTempRowid = sqlite4GetTempReg(pParse);
      sqlite4VdbeAddOp2(v, OP_OpenEphemeral, srcTab, nColumn);
................................................................................
      sqlite4VdbeAddOp2(v, OP_Goto, 0, addrTop);
      sqlite4VdbeJumpHere(v, addrIf);
      sqlite4ReleaseTempReg(pParse, regRec);
      sqlite4ReleaseTempReg(pParse, regTempRowid);
    }
  }else{
    /* This is the case if the data for the INSERT is coming from a VALUES
    ** clause
    */
    NameContext sNC;
    memset(&sNC, 0, sizeof(sNC));
    sNC.pParse = pParse;
    srcTab = -1;
    assert( useTempTable==0 );
    nColumn = pList ? pList->nExpr : 0;
    for(i=0; i<nColumn; i++){
................................................................................
  */
  if( IsVirtual(pTab) ){
    for(i=0; i<pTab->nCol; i++){
      nHidden += (IsHiddenColumn(&pTab->aCol[i]) ? 1 : 0);
    }
  }
  if( pColumn==0 && nColumn && nColumn!=(pTab->nCol-nHidden) ){
    sqlite4ErrorMsg(pParse, 
       "table %S has %d columns but %d values were supplied",
       pTabList, 0, pTab->nCol-nHidden, nColumn);
    goto insert_cleanup;
  }
  if( pColumn!=0 && nColumn!=pColumn->nId ){
    sqlite4ErrorMsg(pParse, "%d values for %d columns", nColumn, pColumn->nId);
    goto insert_cleanup;
  }

  /* If the INSERT statement included an IDLIST term, then make sure
  ** all elements of the IDLIST really are columns of the table and 
  ** remember the column indices.
  **
  ** If the table has an INTEGER PRIMARY KEY column and that column
  ** is named in the IDLIST, then record in the keyColumn variable
  ** the index into IDLIST of the primary key column.  keyColumn is
  ** the index of the primary key as it appears in IDLIST, not as
  ** is appears in the original table.  (The index of the primary
  ** key in the original table is pTab->iPKey.)
  */
  if( pColumn ){
    for(i=0; i<pColumn->nId; i++){
      pColumn->a[i].idx = -1;
    }
    for(i=0; i<pColumn->nId; i++){

      for(j=0; j<pTab->nCol; j++){
        if( sqlite4StrICmp(pColumn->a[i].zName, pTab->aCol[j].zName)==0 ){
          pColumn->a[i].idx = j;
          if( j==pTab->iPKey ){
            keyColumn = i;
          }
          break;
        }
      }
      if( j>=pTab->nCol ){
        if( sqlite4IsRowid(pColumn->a[i].zName) ){
          keyColumn = i;
        }else{
          sqlite4ErrorMsg(pParse, "table %S has no column named %s",
              pTabList, 0, pColumn->a[i].zName);
          pParse->checkSchema = 1;
          goto insert_cleanup;
        }
      }
    }
  }

  /* If there is no IDLIST term but the table has an integer primary
  ** key, the set the keyColumn variable to the primary key column index
  ** in the original table definition.
  */
  if( pColumn==0 && nColumn>0 ){
    keyColumn = pTab->iPKey;
  }
    
  /* Initialize the count of rows to be inserted
  */
  if( db->flags & SQLITE_CountRows ){
    regRowCount = ++pParse->nMem;
    sqlite4VdbeAddOp2(v, OP_Integer, 0, regRowCount);
  }

  /* If this is not a view, open the table and and all indices */







  if( !isView ){
    int nIdx;

    baseCur = pParse->nTab;
    nIdx = sqlite4OpenTableAndIndices(pParse, pTab, baseCur, OP_OpenWrite);
    aRegIdx = sqlite4DbMallocRaw(db, sizeof(int)*(nIdx+1));
    if( aRegIdx==0 ){
      goto insert_cleanup;
    }
    for(i=0; i<nIdx; i++){
      aRegIdx[i] = ++pParse->nMem;  /* Register in which to store key */
      pParse->nMem++;               /* Extra register for data */
................................................................................
    **         goto C
    **      D: ...
    */
    addrCont = sqlite4VdbeAddOp1(v, OP_Yield, dest.iParm);
    addrInsTop = sqlite4VdbeAddOp1(v, OP_If, regEof);
  }

  /* Allocate registers for holding the rowid of the new row,
  ** the content of the new row, and the assemblied row record.
  */


  regRowid = regIns = pParse->nMem+1;
  pParse->nMem += pTab->nCol + 1;

  if( IsVirtual(pTab) ){


    regRowid++;
    pParse->nMem++;
  }
  regData = regRowid+1;

  /* Run the BEFORE and INSTEAD OF triggers, if there are any
  */
  endOfLoop = sqlite4VdbeMakeLabel(v);
  if( tmask & TRIGGER_BEFORE ){
    int regCols = sqlite4GetTempRange(pParse, pTab->nCol+1);

................................................................................
    /* Fire BEFORE or INSTEAD OF triggers */
    sqlite4CodeRowTrigger(pParse, pTrigger, TK_INSERT, 0, TRIGGER_BEFORE, 
        pTab, regCols-pTab->nCol-1, onError, endOfLoop);

    sqlite4ReleaseTempRange(pParse, regCols, pTab->nCol+1);
  }

  /* Push the record number for the new entry onto the stack.  The
  ** record number is a randomly generate integer created by NewRowid
  ** except when the table has an INTEGER PRIMARY KEY column, in which
  ** case the record number is the same as that column. 
  */
  if( !isView ){







    if( IsVirtual(pTab) ){
      /* The row that the VUpdate opcode will delete: none */
      sqlite4VdbeAddOp2(v, OP_Null, 0, regIns);
    }
    if( keyColumn>=0 ){
      if( useTempTable ){
        sqlite4VdbeAddOp3(v, OP_Column, srcTab, keyColumn, regRowid);
................................................................................
    }else if( IsVirtual(pTab) ){
      sqlite4VdbeAddOp2(v, OP_Null, 0, regRowid);
    }else{
      sqlite4VdbeAddOp3(v, OP_NewRowid, baseCur, regRowid, regAutoinc);
      appendFlag = 1;
    }
    autoIncStep(pParse, regAutoinc, regRowid);


    /* Push onto the stack, data for all columns of the new entry, beginning
    ** with the first column.
    */
    nHidden = 0;
    for(i=0; i<pTab->nCol; i++){
      int iRegStore = regRowid+1+i;
      if( i==pTab->iPKey ){
        /* The value of the INTEGER PRIMARY KEY column is always a NULL.
        ** Whenever this column is read, the record number will be substituted
        ** in its place.  So will fill this column with a NULL to avoid
        ** taking up data space with information that will never be used. */
        sqlite4VdbeAddOp2(v, OP_Null, 0, iRegStore);
        continue;
      }
      if( pColumn==0 ){
        if( IsHiddenColumn(&pTab->aCol[i]) ){
          assert( IsVirtual(pTab) );
          j = -1;
          nHidden++;
        }else{
          j = i - nHidden;
................................................................................
      sqlite4VdbeAddOp4(v, OP_VUpdate, 1, pTab->nCol+2, regIns, pVTab, P4_VTAB);
      sqlite4VdbeChangeP5(v, onError==OE_Default ? OE_Abort : onError);
      sqlite4MayAbort(pParse);
    }else
#endif
    {
      int isReplace;    /* Set to true if constraints may cause a replace */
      sqlite4GenerateConstraintChecks(pParse, pTab, baseCur, regIns, aRegIdx,
          keyColumn>=0, 0, onError, endOfLoop, &isReplace
      );
      sqlite4FkCheck(pParse, pTab, 0, regIns);
      sqlite4CompleteInsertion(
          pParse, pTab, baseCur, regIns, aRegIdx, 0, appendFlag, isReplace==0
      );
    }
  }

  /* Update the count of rows that are inserted
  */
  if( (db->flags & SQLITE_CountRows)!=0 ){
................................................................................
  }else if( pSelect ){
    sqlite4VdbeAddOp2(v, OP_Goto, 0, addrCont);
    sqlite4VdbeJumpHere(v, addrInsTop);
  }

  if( !IsVirtual(pTab) && !isView ){
    /* Close all tables opened */
    sqlite4VdbeAddOp1(v, OP_Close, baseCur);
    for(idx=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, idx++){
      sqlite4VdbeAddOp1(v, OP_Close, idx+baseCur);
    }
  }

insert_end:
  /* Update the sqlite_sequence table by storing the content of the
  ** maximum rowid counter values recorded while inserting into
................................................................................
#ifdef pTrigger
 #undef pTrigger
#endif
#ifdef tmask
 #undef tmask
#endif












































































































/*








































** Generate code to do constraint checks prior to an INSERT or an UPDATE.
**
** The input is a range of consecutive registers as follows:
**
**    1.  The rowid of the row after the update.
**
**    2.  The data in the first column of the entry after the update.
................................................................................
** read/write cursors with cursor number baseCur+i for the i-th cursor.
** Except, if there is no possibility of a REPLACE action then
** cursors do not need to be open for indices where aRegIdx[i]==0.
*/
void sqlite4GenerateConstraintChecks(
  Parse *pParse,      /* The parser context */
  Table *pTab,        /* the table into which we are inserting */
  int baseCur,        /* Index of a read/write cursor pointing at pTab */
  int regRowid,       /* Index of the range of input registers */
  int *aRegIdx,       /* Register used by each index.  0 for unused indices */

  int rowidChng,      /* True if the rowid might collide with existing entry */
  int isUpdate,       /* True for UPDATE, False for INSERT */

  int overrideError,  /* Override onError to this if not OE_Default */
  int ignoreDest,     /* Jump to this label on an OE_Ignore resolution */
  int *pbMayReplace   /* OUT: Set to true if constraint may cause a replace */
){

  int i;              /* loop counter */
  Vdbe *v;            /* VDBE under constrution */
  int nCol;           /* Number of columns */
  int onError;        /* Conflict resolution strategy */
  int j1;             /* Addresss of jump instruction */
  int j2 = 0, j3;     /* Addresses of jump instructions */
  int regData;        /* Register containing first data column */
  int iCur;           /* Table cursor number */
  Index *pIdx;         /* Pointer to one of the indices */
  int seenReplace = 0; /* True if REPLACE is used to resolve INT PK conflict */
  int regOldRowid = (rowidChng && isUpdate) ? rowidChng : regRowid;

  v = sqlite4GetVdbe(pParse);
  assert( v!=0 );
  assert( pTab->pSelect==0 );  /* This table is not a VIEW */
  nCol = pTab->nCol;
  regData = regRowid + 1;




  /* Test all NOT NULL constraints.
  */
  for(i=0; i<nCol; i++){
    if( i==pTab->iPKey ){
      continue;
    }
    onError = pTab->aCol[i].notNull;
    if( onError==OE_None ) continue;
    if( overrideError!=OE_Default ){
      onError = overrideError;
    }else if( onError==OE_Default ){
      onError = OE_Abort;
    }
    if( onError==OE_Replace && pTab->aCol[i].pDflt==0 ){
      onError = OE_Abort;
    }
    assert( onError==OE_Rollback || onError==OE_Abort || onError==OE_Fail
        || onError==OE_Ignore || onError==OE_Replace );
    switch( onError ){
      case OE_Abort:
        sqlite4MayAbort(pParse);
      case OE_Rollback:
      case OE_Fail: {
        char *zMsg;
        sqlite4VdbeAddOp3(v, OP_HaltIfNull,
                                  SQLITE_CONSTRAINT, onError, regData+i);
        zMsg = sqlite4MPrintf(pParse->db, "%s.%s may not be NULL",
                              pTab->zName, pTab->aCol[i].zName);
        sqlite4VdbeChangeP4(v, -1, zMsg, P4_DYNAMIC);
        break;
      }
      case OE_Ignore: {
        sqlite4VdbeAddOp2(v, OP_IsNull, regData+i, ignoreDest);
        break;
      }
      default: {
        assert( onError==OE_Replace );
        j1 = sqlite4VdbeAddOp1(v, OP_NotNull, regData+i);
        sqlite4ExprCode(pParse, pTab->aCol[i].pDflt, regData+i);
        sqlite4VdbeJumpHere(v, j1);
        break;
      }
    }
  }

  /* Test all CHECK constraints
  */
#ifndef SQLITE_OMIT_CHECK
  if( pTab->pCheck && (pParse->db->flags & SQLITE_IgnoreChecks)==0 ){
    int allOk = sqlite4VdbeMakeLabel(v);
    pParse->ckBase = regData;
    sqlite4ExprIfTrue(pParse, pTab->pCheck, allOk, SQLITE_JUMPIFNULL);
    onError = overrideError!=OE_Default ? overrideError : OE_Abort;
    if( onError==OE_Ignore ){
      sqlite4VdbeAddOp2(v, OP_Goto, 0, ignoreDest);
    }else{
      if( onError==OE_Replace ) onError = OE_Abort; /* IMP: R-15569-63625 */
      sqlite4HaltConstraint(pParse, onError, 0, 0);

    }
    sqlite4VdbeResolveLabel(v, allOk);
  }
#endif /* !defined(SQLITE_OMIT_CHECK) */

  /* If we have an INTEGER PRIMARY KEY, make sure the primary key
  ** of the new record does not previously exist.  Except, if this
  ** is an UPDATE and the primary key is not changing, that is OK.
  */
  if( rowidChng ){
    onError = pTab->keyConf;
    if( overrideError!=OE_Default ){
      onError = overrideError;
    }else if( onError==OE_Default ){
      onError = OE_Abort;
    }
    
    if( isUpdate ){
      j2 = sqlite4VdbeAddOp3(v, OP_Eq, regRowid, 0, rowidChng);
    }
    j3 = sqlite4VdbeAddOp3(v, OP_NotExists, baseCur, 0, regRowid);
    switch( onError ){
      default: {
        onError = OE_Abort;
        /* Fall thru into the next case */
      }
      case OE_Rollback:
      case OE_Abort:
      case OE_Fail: {
        sqlite4HaltConstraint(
          pParse, onError, "PRIMARY KEY must be unique", P4_STATIC);
        break;
      }
      case OE_Replace: {
        /* If there are DELETE triggers on this table and the
        ** recursive-triggers flag is set, call GenerateRowDelete() to
        ** remove the conflicting row from the the table. This will fire
        ** the triggers and remove both the table and index b-tree entries.
        **
        ** Otherwise, if there are no triggers or the recursive-triggers
        ** flag is not set, but the table has one or more indexes, call 
        ** GenerateRowIndexDelete(). This removes the index b-tree entries 
        ** only. The table b-tree entry will be replaced by the new entry 
        ** when it is inserted.  
        **
        ** If either GenerateRowDelete() or GenerateRowIndexDelete() is called,
        ** also invoke MultiWrite() to indicate that this VDBE may require
        ** statement rollback (if the statement is aborted after the delete
        ** takes place). Earlier versions called sqlite4MultiWrite() regardless,
        ** but being more selective here allows statements like:
        **
        **   REPLACE INTO t(rowid) VALUES($newrowid)
        **
        ** to run without a statement journal if there are no indexes on the
        ** table.
        */
        Trigger *pTrigger = 0;
        if( pParse->db->flags&SQLITE_RecTriggers ){
          pTrigger = sqlite4TriggersExist(pParse, pTab, TK_DELETE, 0, 0);
        }
        if( pTrigger || sqlite4FkRequired(pParse, pTab, 0, 0) ){
          sqlite4MultiWrite(pParse);
          sqlite4GenerateRowDelete(
              pParse, pTab, baseCur, regRowid, 0, pTrigger, OE_Replace
          );
        }else if( pTab->pIndex ){
          sqlite4MultiWrite(pParse);
          sqlite4GenerateRowIndexDelete(pParse, pTab, baseCur, 0);
        }
        seenReplace = 1;
        break;
      }
      case OE_Ignore: {
        assert( seenReplace==0 );
        sqlite4VdbeAddOp2(v, OP_Goto, 0, ignoreDest);
        break;
      }
    }
    sqlite4VdbeJumpHere(v, j3);
    if( isUpdate ){
      sqlite4VdbeJumpHere(v, j2);
    }
  }

  /* Test all UNIQUE constraints by creating entries for each UNIQUE
  ** index and making sure that duplicate entries do not already exist.
  ** Add the new records to the indices as we go.
  */
  for(iCur=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, iCur++){
    int regIdx;
    int regR;




    if( aRegIdx[iCur]==0 ) continue;  /* Skip unused indices */

    /* Create a key for accessing the index entry */



    regIdx = sqlite4GetTempRange(pParse, pIdx->nColumn+1);

    for(i=0; i<pIdx->nColumn; i++){
      int idx = pIdx->aiColumn[i];
      if( idx==pTab->iPKey ){
        sqlite4VdbeAddOp2(v, OP_SCopy, regRowid, regIdx+i);
      }else{




        sqlite4VdbeAddOp2(v, OP_SCopy, regData+idx, regIdx+i);
      }
    }
    sqlite4VdbeAddOp2(v, OP_SCopy, regRowid, regIdx+i);
    sqlite4VdbeAddOp2(v, OP_MakeKey, baseCur+iCur+1, aRegIdx[iCur]+1);
    sqlite4VdbeAddOp3(v, OP_MakeRecord, regIdx, pIdx->nColumn+1, aRegIdx[iCur]);
    sqlite4VdbeChangeP4(v, -1, sqlite4IndexAffinityStr(v, pIdx), P4_TRANSIENT);
    sqlite4ExprCacheAffinityChange(pParse, regIdx, pIdx->nColumn+1);


    /* Find out what action to take in case there is an indexing conflict */




    onError = pIdx->onError;
    if( onError==OE_None ){ 
      sqlite4ReleaseTempRange(pParse, regIdx, pIdx->nColumn+1);
      continue;  /* pIdx is not a UNIQUE index */

    }







    if( overrideError!=OE_Default ){
      onError = overrideError;
    }else if( onError==OE_Default ){
      onError = OE_Abort;
    }
    if( seenReplace ){
      if( onError==OE_Ignore ) onError = OE_Replace;
      else if( onError==OE_Fail ) onError = OE_Abort;
    }
    
    /* Check to see if the new index entry will be unique */
    regR = sqlite4GetTempReg(pParse);
    sqlite4VdbeAddOp2(v, OP_SCopy, regOldRowid, regR);
    j3 = sqlite4VdbeAddOp4(v, OP_IsUnique, baseCur+iCur+1, 0,
                           regR, SQLITE_INT_TO_PTR(regIdx),
                           P4_INT32);
    sqlite4ReleaseTempRange(pParse, regIdx, pIdx->nColumn+1);

    /* Generate code that executes if the new index entry is not unique */
    assert( onError==OE_Rollback || onError==OE_Abort || onError==OE_Fail
        || onError==OE_Ignore || onError==OE_Replace );
    switch( onError ){
      case OE_Rollback:
      case OE_Abort:
      case OE_Fail: {
        int j;
        StrAccum errMsg;
        const char *zSep;
        char *zErr;

        sqlite4StrAccumInit(&errMsg, 0, 0, 200);
        errMsg.db = pParse->db;
        zSep = pIdx->nColumn>1 ? "columns " : "column ";
        for(j=0; j<pIdx->nColumn; j++){
          char *zCol = pTab->aCol[pIdx->aiColumn[j]].zName;

          sqlite4StrAccumAppend(&errMsg, zSep, -1);
          zSep = ", ";
          sqlite4StrAccumAppend(&errMsg, zCol, -1);
        }
        sqlite4StrAccumAppend(&errMsg,
            pIdx->nColumn>1 ? " are not unique" : " is not unique", -1);
        zErr = sqlite4StrAccumFinish(&errMsg);
        sqlite4HaltConstraint(pParse, onError, zErr, 0);
        sqlite4DbFree(errMsg.db, zErr);
        break;
      }
      case OE_Ignore: {
        assert( seenReplace==0 );
        sqlite4VdbeAddOp2(v, OP_Goto, 0, ignoreDest);
        break;
      }
      default: {


        Trigger *pTrigger = 0;
        assert( onError==OE_Replace );
        sqlite4MultiWrite(pParse);
        if( pParse->db->flags&SQLITE_RecTriggers ){
          pTrigger = sqlite4TriggersExist(pParse, pTab, TK_DELETE, 0, 0);
        }
        sqlite4GenerateRowDelete(
            pParse, pTab, baseCur, regR, 0, pTrigger, OE_Replace
        );
        seenReplace = 1;

        break;
      }
    }


    sqlite4VdbeJumpHere(v, j3);


    sqlite4ReleaseTempReg(pParse, regR);
  }
  
  if( pbMayReplace ){
    *pbMayReplace = seenReplace;
  }
}

/*
** This routine generates code to finish the INSERT or UPDATE operation
** that was started by a prior call to sqlite4GenerateConstraintChecks.
** A consecutive range of registers starting at regRowid contains the
** rowid and the content to be inserted.
**
** The arguments to this routine should be the same as the first six
** arguments to sqlite4GenerateConstraintChecks.











*/
void sqlite4CompleteInsertion(
  Parse *pParse,      /* The parser context */
  Table *pTab,        /* the table into which we are inserting */
  int baseCur,        /* Index of a read/write cursor pointing at pTab */
  int regRowid,       /* Range of content */
  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 */
){
  int i;
  Vdbe *v;
  int nIdx;
  Index *pIdx;
  u8 pik_flags;
  int regData;
  int regRec;

  v = sqlite4GetVdbe(pParse);

  assert( v!=0 );
  assert( pTab->pSelect==0 );  /* This table is not a VIEW */
  for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){}
  for(i=nIdx-1; i>=0; i--){
    if( aRegIdx[i]==0 ) continue;
    sqlite4VdbeAddOp3(v, OP_IdxInsert, baseCur+i+1, aRegIdx[i], aRegIdx[i]+1);
    if( useSeekResult ){
      sqlite4VdbeChangeP5(v, OPFLAG_USESEEKRESULT);
    }
  }
  regData = regRowid + 1;
  regRec = sqlite4GetTempReg(pParse);
  sqlite4VdbeAddOp3(v, OP_MakeRecord, regData, pTab->nCol, regRec);
  sqlite4TableAffinityStr(v, pTab);
  sqlite4ExprCacheAffinityChange(pParse, regData, pTab->nCol);
  if( pParse->nested ){
    pik_flags = 0;
  }else{
    pik_flags = OPFLAG_NCHANGE;
    pik_flags |= (isUpdate?OPFLAG_ISUPDATE:OPFLAG_LASTROWID);
  }
  if( appendBias ){
    pik_flags |= OPFLAG_APPEND;
  }
  if( useSeekResult ){
    pik_flags |= OPFLAG_USESEEKRESULT;
  }
  sqlite4VdbeAddOp3(v, OP_Insert, baseCur, regRec, regRowid);
  if( !pParse->nested ){
    sqlite4VdbeChangeP4(v, -1, pTab->zName, P4_TRANSIENT);
  }
  sqlite4VdbeChangeP5(v, pik_flags);







}

/*
** Generate code that will open cursors for a table and for all
** indices of that table.  The "baseCur" parameter is the cursor number used
** for the table.  Indices are opened on subsequent cursors.
**
** Return the number of indices on the table.
*/
int sqlite4OpenTableAndIndices(
  Parse *pParse,   /* Parsing context */
  Table *pTab,     /* Table to be opened */
  int baseCur,     /* Cursor number assigned to the table */
  int op           /* OP_OpenRead or OP_OpenWrite */
){
  int i;

  int iDb;




















  Index *pIdx;
  Vdbe *v;

  if( IsVirtual(pTab) ) return 0;
  iDb = sqlite4SchemaToIndex(pParse->db, pTab->pSchema);



  v = sqlite4GetVdbe(pParse);
  assert( v!=0 );
  sqlite4OpenTable(pParse, baseCur, iDb, pTab, op);
  for(i=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
    KeyInfo *pKey = sqlite4IndexKeyinfo(pParse, pIdx);
    assert( pIdx->pSchema==pTab->pSchema );
    sqlite4VdbeAddOp4(v, op, i+baseCur, pIdx->tnum, iDb,
                      (char*)pKey, P4_KEYINFO_HANDOFF);
    VdbeComment((v, "%s", pIdx->zName));
  }
  if( pParse->nTab<baseCur+i ){
    pParse->nTab = baseCur+i;
  }
  return i-1;
}


#ifdef SQLITE_TEST
/*
** The following global variable is incremented whenever the
** transfer optimization is used.  This is used for testing

void sqlite4OpenTable(
  Parse *p,       /* Generate code into this VDBE */
  int iCur,       /* The cursor number of the table */
  int iDb,        /* The database index in sqlite4.aDb[] */
  Table *pTab,    /* The table to be opened */
  int opcode      /* OP_OpenRead or OP_OpenWrite */
){
  assert( 0 );

}

/*
** Open VDBE cursor iCur to access index pIdx. pIdx is guaranteed to be
** a part of database iDb.
*/
void sqlite4OpenIndex(
  Parse *p,                       /* Current parser context */
  int iCur,                       /* The cursor number of the cursor to open */
  int iDb,                        /* The database index in sqlite4.aDb[] */
  Index *pIdx,                    /* The index to be opened */
  int opcode                      /* OP_OpenRead or OP_OpenWrite */
){
  KeyInfo *pKey;                /* KeyInfo structure describing PK index */
  Vdbe *v;                      /* VM to write code into */

  assert( opcode==OP_OpenWrite || opcode==OP_OpenRead );

  assert( pIdx->tnum>0 );

  v = sqlite4GetVdbe(p);
  pKey = sqlite4IndexKeyinfo(p, pIdx);
  testcase( pKey==0 );

  sqlite4VdbeAddOp3(v, opcode, iCur, pIdx->tnum, iDb);
  sqlite4VdbeChangeP4(v, -1, (const char *)pKey, P4_KEYINFO_HANDOFF);
  VdbeComment((v, "%s", pIdx->zName));
}

/*
** Generate code that will open the primary key of a table for either 
** reading (if opcode==OP_OpenRead) or writing (if opcode==OP_OpenWrite).
*/
void sqlite4OpenPrimaryKey(
  Parse *p,                       /* Current parser context */
  int iCur,                       /* The cursor number of the cursor to open */
  int iDb,                        /* The database index in sqlite4.aDb[] */
  Table *pTab,                    /* The table to be opened */
  int opcode                      /* OP_OpenRead or OP_OpenWrite */
){
  assert( opcode==OP_OpenWrite || opcode==OP_OpenRead );
  if( IsVirtual(pTab)==0 ){
    Index *pIdx;                  /* PRIMARY KEY index for table pTab */

    pIdx = sqlite4FindPrimaryKey(pTab, 0);
    sqlite4TableLock(p, iDb, pIdx->tnum, (opcode==OP_OpenWrite), pTab->zName);
    sqlite4OpenIndex(p, iCur, iDb, pIdx, opcode);
    assert( pIdx->eIndexType==SQLITE_INDEX_PRIMARYKEY );
  }
}

/*
** Return a pointer to the column affinity string associated with index
** pIdx. A column affinity string has one character for each column in 
** the index key. If the index is the PRIMARY KEY of its table, the key
** consists of the index columns only. Otherwise, it consists of the
** indexed columns, followed by the columns that make up the tables PRIMARY
** KEY. For each column in the index key, the corresponding character of
** the affinity string is set according to the column affinity, as follows:
**
**  Character      Column affinity
**  ------------------------------
**  'a'            TEXT
**  'b'            NONE
**  'c'            NUMERIC
**  'd'            INTEGER
**  'e'            REAL
**



** 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 sqlite4DeleteIndex() is called.
*/
const char *sqlite4IndexAffinityStr(Vdbe *v, Index *pIdx){

  /* The first time a column affinity string for a particular index is
  ** required, it is allocated and populated here. It is then stored as
  ** a member of the Index structure for subsequent use. The column 

  ** affinity string will eventually be deleted by sqliteDeleteIndex() 
  ** when the Index structure itself is cleaned up.  */




  if( !pIdx->zColAff ){
    sqlite4 *db = sqlite4VdbeDb(v);
    Table *pTab = pIdx->pTable;   /* Table pIdx is attached to */
    int n;                        /* Iterator variable for zAff */
    Index *pPk;                   /* Primary key on same table as pIdx */
    Index *p;                     /* Iterator variable */
    char *zAff;                   /* Affinity string to populate and return */
    int nAff;                     /* Characters in zAff */

    /* Determine how many characters are in the affinity string. There is
    ** one character for each indexed column, and, if the index is not itself
    ** the primary key, one character for each column in the primary key
    ** of the table pIdx indexes.  */ 
    nAff = pIdx->nColumn;
    pPk = sqlite4FindPrimaryKey(pTab, 0);
    if( pIdx!=pPk ){
      nAff += pPk->nColumn;
    }

    /* Allocate space for the affinity string */
    zAff = pIdx->zColAff = (char *)sqlite4DbMallocRaw(0, nAff+1);

    if( !zAff ){
      db->mallocFailed = 1;
      return 0;
    }

    /* Populate the affinity string. This loop runs either once or twice.
    ** The first iteration populates zAff with affinities according to the
    ** columns indexed by pIdx.  If pIdx is not itself the table's primary 
    ** key, then the second iteration of the loop adds the primary key 
    ** columns to zAff.  */
    for(n=0, p=pIdx; p; p=(p==pPk ? 0 : pPk)){
      int i;
      for(i=0; i<p->nColumn; i++){

        int iCol = p->aiColumn[i];
        zAff[n++] = (iCol<0) ? SQLITE_AFF_INTEGER : pTab->aCol[iCol].affinity;
      }

    }
    zAff[n] = 0;
  }
 
  return pIdx->zColAff;
}

/*
** Set P4 of the most recently inserted opcode to a column affinity
................................................................................

  for(i=iStartAddr; i<iEnd; i++){
    VdbeOp *pOp = sqlite4VdbeGetOp(v, i);
    assert( pOp!=0 );
    if( pOp->opcode==OP_OpenRead && pOp->p3==iDb ){
      Index *pIndex;
      int tnum = pOp->p2;



      for(pIndex=pTab->pIndex; pIndex; pIndex=pIndex->pNext){
        if( tnum==pIndex->tnum ){
          return 1;
        }
      }
    }
#ifndef SQLITE_OMIT_VIRTUALTABLE
................................................................................
  int appendFlag = 0;   /* True if the insert is likely to be an append */

  /* Register allocations */
  int regFromSelect = 0;/* Base register for data coming from SELECT */
  int regAutoinc = 0;   /* Register holding the AUTOINCREMENT counter */
  int regRowCount = 0;  /* Memory cell used for the row counter */
  int regIns;           /* Block of regs holding rowid+data being inserted */

  int regData;          /* register holding first column to insert */
  int regEof = 0;       /* Register recording end of SELECT data */
  int *aRegIdx = 0;     /* One register allocated to each index */

  int iPk;                        /* Cursor offset of PK index cursor */
  Index *pPk;                     /* Primary key for table pTab */
  int bImplicitPK;                /* True if table pTab has an implicit PK */
  int regContent;                 /* First register in column value array */
  int regRowid;                   /* If bImplicitPK, register holding IPK */


#ifndef SQLITE_OMIT_TRIGGER
  int isView;                 /* True if attempting to insert into a view */
  Trigger *pTrigger;          /* List of triggers on pTab, if required */
  int tmask;                  /* Mask of trigger times */
#endif

................................................................................
  iDb = sqlite4SchemaToIndex(db, pTab->pSchema);
  assert( iDb<db->nDb );
  pDb = &db->aDb[iDb];
  zDb = pDb->zName;
  if( sqlite4AuthCheck(pParse, SQLITE_INSERT, pTab->zName, 0, zDb) ){
    goto insert_cleanup;
  }

  /* Set bImplicitPK to true for an implicit PRIMARY KEY, or false otherwise */
  pPk = sqlite4FindPrimaryKey(pTab, &iPk);
  bImplicitPK = pPk->aiColumn[0]==-1;

  /* Figure out if we have any triggers and if the table being
  ** inserted into is a view
  */
#ifndef SQLITE_OMIT_TRIGGER
  pTrigger = sqlite4TriggersExist(pParse, pTab, TK_INSERT, 0, &tmask);
  isView = pTab->pSelect!=0;
................................................................................
# undef isView
# define isView 0
#endif
  assert( (pTrigger && tmask) || (pTrigger==0 && tmask==0) );

  /* If pTab is really a view, make sure it has been initialized.
  ** ViewGetColumnNames() is a no-op if pTab is not a view (or virtual 
  ** module table).  */

  if( sqlite4ViewGetColumnNames(pParse, pTab) ){
    goto insert_cleanup;
  }

  /* Ensure that:
  **   (a) the table is not read-only (e.g. sqlite_master, sqlite_stat), and
  **   (b) that if it is a view then ON INSERT triggers exist
  */
  if( sqlite4IsReadOnly(pParse, pTab, tmask) ){
    goto insert_cleanup;
  }

  /* Allocate a VDBE and begin a write transaction */

  v = sqlite4GetVdbe(pParse);
  if( v==0 ) goto insert_cleanup;
  if( pParse->nested==0 ) sqlite4VdbeCountChanges(v);
  sqlite4BeginWriteOperation(pParse, pSelect || pTrigger, iDb);

#ifndef SQLITE_OMIT_XFER_OPT
  /* If the statement is of the form
................................................................................
  if( pColumn==0 && xferOptimization(pParse, pTab, pSelect, onError, iDb) ){
    assert( !pTrigger );
    assert( pList==0 );
    goto insert_end;
  }
#endif /* SQLITE_OMIT_XFER_OPT */






  /* Figure out how many columns of data are supplied.  If the data
  ** is coming from a SELECT statement, then generate a co-routine that
  ** produces a single row of the SELECT on each invocation.  The
  ** co-routine is the common header to the 3rd and 4th templates.
  */
  if( pSelect ){
    /* Data is coming from a SELECT.  Generate code to implement that SELECT
................................................................................
      **         if EOF goto M
      **         insert row from R..R+n into temp table
      **         goto L
      **      M: ...
      */
      int regRec;          /* Register to hold packed record */
      int regTempRowid;    /* Register to hold temp table ROWID */
      int regTempKey;      /* Register to hold key encoded rowid */
      int addrTop;         /* Label "L" */
      int addrIf;          /* Address of jump to M */

      srcTab = pParse->nTab++;
      regRec = sqlite4GetTempReg(pParse);
      regTempRowid = sqlite4GetTempReg(pParse);
      sqlite4VdbeAddOp2(v, OP_OpenEphemeral, srcTab, nColumn);
................................................................................
      sqlite4VdbeAddOp2(v, OP_Goto, 0, addrTop);
      sqlite4VdbeJumpHere(v, addrIf);
      sqlite4ReleaseTempReg(pParse, regRec);
      sqlite4ReleaseTempReg(pParse, regTempRowid);
    }
  }else{
    /* This is the case if the data for the INSERT is coming from a VALUES
    ** (or DEFAULT VALUES) clause. Resolve all references in the VALUES(...)
    ** expressions.  */ 
    NameContext sNC;
    memset(&sNC, 0, sizeof(sNC));
    sNC.pParse = pParse;
    srcTab = -1;
    assert( useTempTable==0 );
    nColumn = pList ? pList->nExpr : 0;
    for(i=0; i<nColumn; i++){
................................................................................
  */
  if( IsVirtual(pTab) ){
    for(i=0; i<pTab->nCol; i++){
      nHidden += (IsHiddenColumn(&pTab->aCol[i]) ? 1 : 0);
    }
  }
  if( pColumn==0 && nColumn && nColumn!=(pTab->nCol-nHidden) ){
    sqlite4ErrorMsg(pParse,
       "table %S has %d columns but %d values were supplied",
       pTabList, 0, pTab->nCol-nHidden, nColumn);
    goto insert_cleanup;
  }
  if( pColumn!=0 && nColumn!=pColumn->nId ){
    sqlite4ErrorMsg(pParse, "%d values for %d columns", nColumn, pColumn->nId);
    goto insert_cleanup;
  }

  /* If the INSERT statement included an IDLIST term, then make sure
  ** all elements of the IDLIST really are columns of the table. Set
  ** the pColumn->a[iCol].idx variables to indicate which column of the
  ** table each IDLIST element corresponds to.






  */
  if( pColumn ){
    for(i=0; i<pColumn->nId; i++){
      pColumn->a[i].idx = -1;
    }
    for(i=0; i<pColumn->nId; i++){
      char *zTest = pColumn->a[i].zName;
      for(j=0; j<pTab->nCol; j++){
        if( sqlite4StrICmp(zTest, pTab->aCol[j].zName)==0 ){
          pColumn->a[i].idx = j;



          break;
        }
      }
      if( j==pTab->nCol ){



        sqlite4ErrorMsg(pParse, "table %S has no column named %s",
              pTabList, 0, pColumn->a[i].zName);
        pParse->checkSchema = 1;
        goto insert_cleanup;

      }
    }
  }









  /* Initialize the count of rows to be inserted
  */
  if( db->flags & SQLITE_CountRows ){
    regRowCount = ++pParse->nMem;
    sqlite4VdbeAddOp2(v, OP_Integer, 0, regRowCount);
  }

  /* If this is not a view, open a write cursor on each index. Allocate
  ** a contiguous array of (nIdx+1) registers, where nIdx is the total
  ** number of indexes (including the PRIMARY KEY index). 
  **
  **   Register aRegIdx[0]:         The PRIMARY KEY index key
  **   Register aRegIdx[1..nIdx-1]: Keys for other table indexes 
  **   Register aRegIdx[nIdx]:      Data record for table row.
  */
  if( !isView ){
    int nIdx;

    baseCur = pParse->nTab;
    nIdx = sqlite4OpenAllIndexes(pParse, pTab, baseCur, OP_OpenWrite);
    aRegIdx = sqlite4DbMallocRaw(db, sizeof(int)*(nIdx+1));
    if( aRegIdx==0 ){
      goto insert_cleanup;
    }
    for(i=0; i<nIdx; i++){
      aRegIdx[i] = ++pParse->nMem;  /* Register in which to store key */
      pParse->nMem++;               /* Extra register for data */
................................................................................
    **         goto C
    **      D: ...
    */
    addrCont = sqlite4VdbeAddOp1(v, OP_Yield, dest.iParm);
    addrInsTop = sqlite4VdbeAddOp1(v, OP_If, regEof);
  }

  /* Allocate an array of registers in which to assemble the values for the
  ** new row. If the table has an explicit primary key, we need one register
  ** for each table column. If the table uses an implicit primary key, the
  ** nCol+1 registers are required.  */
  if( bImplicitPK ) regRowid = ++pParse->nMem;
  regContent = pParse->nMem+1;
  pParse->nMem += pTab->nCol;

  if( IsVirtual(pTab) ){
    /* TODO: Fix this */
    regContent++;
    regRowid++;
    pParse->nMem++;
  }


  /* Run the BEFORE and INSTEAD OF triggers, if there are any
  */
  endOfLoop = sqlite4VdbeMakeLabel(v);
  if( tmask & TRIGGER_BEFORE ){
    int regCols = sqlite4GetTempRange(pParse, pTab->nCol+1);

................................................................................
    /* Fire BEFORE or INSTEAD OF triggers */
    sqlite4CodeRowTrigger(pParse, pTrigger, TK_INSERT, 0, TRIGGER_BEFORE, 
        pTab, regCols-pTab->nCol-1, onError, endOfLoop);

    sqlite4ReleaseTempRange(pParse, regCols, pTab->nCol+1);
  }






  if( !isView ){
    /* If this table has an implicit PRIMARY KEY, populate the regRowid
    ** register with the value to use for the new row.  */
    if( bImplicitPK ){
      sqlite4VdbeAddOp2(v, OP_NewRowid, baseCur+iPk, regRowid);
    }

#if 0
    if( IsVirtual(pTab) ){
      /* The row that the VUpdate opcode will delete: none */
      sqlite4VdbeAddOp2(v, OP_Null, 0, regIns);
    }
    if( keyColumn>=0 ){
      if( useTempTable ){
        sqlite4VdbeAddOp3(v, OP_Column, srcTab, keyColumn, regRowid);
................................................................................
    }else if( IsVirtual(pTab) ){
      sqlite4VdbeAddOp2(v, OP_Null, 0, regRowid);
    }else{
      sqlite4VdbeAddOp3(v, OP_NewRowid, baseCur, regRowid, regAutoinc);
      appendFlag = 1;
    }
    autoIncStep(pParse, regAutoinc, regRowid);
#endif

    /* Push onto the stack, data for all columns of the new entry, beginning
    ** with the first column.
    */
    nHidden = 0;
    for(i=0; i<pTab->nCol; i++){
      int iRegStore = regContent + i;








      if( pColumn==0 ){
        if( IsHiddenColumn(&pTab->aCol[i]) ){
          assert( IsVirtual(pTab) );
          j = -1;
          nHidden++;
        }else{
          j = i - nHidden;
................................................................................
      sqlite4VdbeAddOp4(v, OP_VUpdate, 1, pTab->nCol+2, regIns, pVTab, P4_VTAB);
      sqlite4VdbeChangeP5(v, onError==OE_Default ? OE_Abort : onError);
      sqlite4MayAbort(pParse);
    }else
#endif
    {
      int isReplace;    /* Set to true if constraints may cause a replace */
      sqlite4GenerateConstraintChecks(pParse, pTab, baseCur, 
          regContent, aRegIdx, keyColumn>=0, 0, onError, endOfLoop, &isReplace
      );
      sqlite4FkCheck(pParse, pTab, 0, regIns);
      sqlite4CompleteInsertion(pParse, pTab, baseCur, 
          regContent, aRegIdx, 0, appendFlag, isReplace==0
      );
    }
  }

  /* Update the count of rows that are inserted
  */
  if( (db->flags & SQLITE_CountRows)!=0 ){
................................................................................
  }else if( pSelect ){
    sqlite4VdbeAddOp2(v, OP_Goto, 0, addrCont);
    sqlite4VdbeJumpHere(v, addrInsTop);
  }

  if( !IsVirtual(pTab) && !isView ){
    /* Close all tables opened */

    for(idx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, idx++){
      sqlite4VdbeAddOp1(v, OP_Close, idx+baseCur);
    }
  }

insert_end:
  /* Update the sqlite_sequence table by storing the content of the
  ** maximum rowid counter values recorded while inserting into
................................................................................
#ifdef pTrigger
 #undef pTrigger
#endif
#ifdef tmask
 #undef tmask
#endif

/*
** Return the name of the iCol'th column in index pIdx.
*/
const char *indexColumnName(Index *pIdx, int iCol){
  int iTbl = pIdx->aiColumn[iCol];
  assert( iTbl>=-1 && iTbl<pIdx->pTable->nCol );
  if( iTbl<0 ){
    assert( pIdx->eIndexType==SQLITE_INDEX_PRIMARYKEY && pIdx->nColumn==1 );
    return "rowid";
  }
  return pIdx->pTable->aCol[iTbl].zName;
}

static void generateNotNullChecks(
  Parse *pParse,                  /* Parse context */
  Table *pTab,                    /* Table to generate checks for */
  int regContent,                 /* Index of the range of input registers */
  int overrideError,              /* Override default OE_* with this */
  int ignoreDest                  /* Jump to this lable if OE_Ignore */
){
  Vdbe *v = pParse->pVdbe;
  int i;

  for(i=0; i<pTab->nCol; i++){
    int onError = pTab->aCol[i].notNull;
    if( onError ){
      if( overrideError!=OE_Default ){
        onError = overrideError;
      }else if( onError==OE_Default ){
        onError = OE_Abort;
      }
      if( onError==OE_Replace && pTab->aCol[i].pDflt==0 ){
        onError = OE_Abort;
      }

      switch( onError ){
        case OE_Abort:
          sqlite4MayAbort(pParse);
        case OE_Rollback:
        case OE_Fail: {
          char *zMsg = sqlite4MPrintf(pParse->db, "%s.%s may not be NULL",
              pTab->zName, pTab->aCol[i].zName
          );
          sqlite4VdbeAddOp4(v, OP_HaltIfNull, 
              SQLITE_CONSTRAINT, onError, regContent+i, zMsg, P4_DYNAMIC
          );
          break;
        }

        case OE_Ignore:
          sqlite4VdbeAddOp2(v, OP_IsNull, regContent+i, ignoreDest);
          break;

        default: {
          int j1 = sqlite4VdbeAddOp1(v, OP_NotNull, regContent+i);
          sqlite4ExprCode(pParse, pTab->aCol[i].pDflt, regContent+i);
          sqlite4VdbeJumpHere(v, j1);
          assert( onError==OE_Replace );
          break;
        }
      }
    }
  }
}

#ifndef SQLITE_OMIT_CHECK
static void generateCheckChecks(
  Parse *pParse,                  /* Parse context */
  Table *pTab,                    /* Table to generate checks for */
  int regContent,                 /* Index of the range of input registers */
  int overrideError,              /* Override default OE_* with this */
  int ignoreDest                  /* Jump to this lable if OE_Ignore */
){
  Vdbe *v = pParse->pVdbe;

  if( pTab->pCheck && (pParse->db->flags & SQLITE_IgnoreChecks)==0 ){
    int onError;
    int allOk = sqlite4VdbeMakeLabel(v);
    pParse->ckBase = regContent;
    sqlite4ExprIfTrue(pParse, pTab->pCheck, allOk, SQLITE_JUMPIFNULL);
    onError = overrideError!=OE_Default ? overrideError : OE_Abort;
    if( onError==OE_Ignore ){
      sqlite4VdbeAddOp2(v, OP_Goto, 0, ignoreDest);
    }else{
      if( onError==OE_Replace ) onError = OE_Abort; /* IMP: R-15569-63625 */
      sqlite4HaltConstraint(pParse, onError, 0, 0);
    }
    sqlite4VdbeResolveLabel(v, allOk);
  }
}
#else /* !defined(SQLITE_OMIT_CHECK) */
# define generateCheckChecks(a,b,c,d,e)
#endif

Index *sqlite4FindPrimaryKey(
  Table *pTab,                    /* Table to locate primary key for */
  int *piPk                       /* OUT: Index of PRIMARY KEY */
){
  Index *p;
  int iPk = 0;
  for(p=pTab->pIndex; p && p->eIndexType!=SQLITE_INDEX_PRIMARYKEY; p=p->pNext){
    iPk++;
  }
  if( piPk ) *piPk = iPk;
  return p;
}

/*
** This function generates code used as part of both INSERT and UPDATE
** statements. The generated code performs two tasks:
**
**   1. Checks all NOT NULL, CHECK and UNIQUE database constraints, 
**      including the implicit NOT NULL and UNIQUE constraints imposed
**      by the PRIMARY KEY definition.
**
**   2. Generates serialized index keys (using OP_MakeKey) for the caller
**      to store in database indexes. This function does not encode the
**      actual data record, just the index keys.
**
** Both INSERT and UPDATE use this function in concert with the
** sqlite4CompleteInsertion(). This function does as described above, and
** then CompleteInsertion() generates code to serialize the data record 
** and do the actual inserts into the database.
**
** regContent:
**   The first in an array of registers that contain the column values
**   for the new row. Register regContent contains the value for the 
**   left-most table column, (regContent+1) contains the value for the next 
**   column, and so on. All entries in this array have had any required
**   affinity transformations applied already. All zero-blobs have been 
**   expanded.
**
**   If the table has an implicit primary key and aRegIdx[0] is not 0 (see
**   below), register (regContent-1) is also valid. It contains the new 
**   implicit integer PRIMARY KEY value.
**
** aRegIdx:
**   Array sized so that there is one entry for each index (including the
**   PK index) attached to the database table. Entries are in the same order
**   as the linked list of Index structures attached to the table. 
**
**   If an array entry is non-zero, it contains the register that the 
**   corresponding index key should be written to. If an entry is zero, then
**   the corresponding index key is not required by the caller and that any 
**   UNIQUE enforced by the index does not need to be checked.
**
** 
**
** Generate code to do constraint checks prior to an INSERT or an UPDATE.
**
** The input is a range of consecutive registers as follows:
**
**    1.  The rowid of the row after the update.
**
**    2.  The data in the first column of the entry after the update.
................................................................................
** read/write cursors with cursor number baseCur+i for the i-th cursor.
** Except, if there is no possibility of a REPLACE action then
** cursors do not need to be open for indices where aRegIdx[i]==0.
*/
void sqlite4GenerateConstraintChecks(
  Parse *pParse,      /* The parser context */
  Table *pTab,        /* the table into which we are inserting */
  int baseCur,        /* First in array of cursors for pTab indexes */
  int regContent,     /* Index of the range of input registers */
  int *aRegIdx,       /* Register used by each index.  0 for unused indices */

  int rowidChng,      /* True if the rowid might collide with existing entry */
  int isUpdate,       /* True for UPDATE, False for INSERT */

  int overrideError,  /* Override onError to this if not OE_Default */
  int ignoreDest,     /* Jump to this label on an OE_Ignore resolution */
  int *pbMayReplace   /* OUT: Set to true if constraint may cause a replace */
){
  Index *pPk;                     /* Primary key index for table pTab */
  int i;              /* loop counter */
  Vdbe *v;            /* VDBE under constrution */
  int nCol;           /* Number of columns */
  int onError;        /* Conflict resolution strategy */



  int iCur;           /* Table cursor number */
  Index *pIdx;         /* Pointer to one of the indices */
  int seenReplace = 0; /* True if REPLACE is used to resolve INT PK conflict */


  v = sqlite4GetVdbe(pParse);
  assert( v!=0 );
  assert( pTab->pSelect==0 );  /* This table is not a VIEW */
  nCol = pTab->nCol;

  pPk = sqlite4FindPrimaryKey(pTab, 0);

  assert( pPk->eIndexType==SQLITE_INDEX_PRIMARYKEY );

  /* Test all NOT NULL constraints. */

  generateNotNullChecks(pParse, pTab, regContent, overrideError, ignoreDest);










































  /* Test all CHECK constraints */












  generateCheckChecks(pParse, pTab, regContent, overrideError, ignoreDest);




















































































  /* Test all UNIQUE constraints by creating entries for each UNIQUE
  ** index and making sure that duplicate entries do not already exist.
  ** Add the new records to the indices as we go.
  */
  for(iCur=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, iCur++){


    int nTmpReg;                  /* Number of temp registers required */
    int regTmp;                   /* First temp register allocated */
    int regShort;                 /* Reg. for number of bytes in short key */

    if( aRegIdx[iCur]==0 ) continue;  /* Skip unused indices */

    /* Create an index key. Primary key indexes consists of just the primary
    ** key values. Other indexes consists of the indexed columns followed by
    ** the primary key values.  */
    nTmpReg = 1 + pIdx->nColumn + (pIdx==pPk ? 0 : pPk->nColumn);
    regTmp = sqlite4GetTempRange(pParse, nTmpReg);
    regShort = regTmp + nTmpReg - 1;
    for(i=0; i<pIdx->nColumn; i++){
      int idx = pIdx->aiColumn[i];

      sqlite4VdbeAddOp2(v, OP_SCopy, regContent+idx, regTmp+i);

    }
    if( pIdx!=pPk ){
      for(i=0; i<pPk->nColumn; i++){
        int idx = pPk->aiColumn[i];
        sqlite4VdbeAddOp2(v, OP_SCopy, regContent+idx, regTmp+i+pIdx->nColumn);
      }
    }


    sqlite4VdbeAddOp3(v, OP_MakeIdxKey, baseCur+iCur, regTmp, aRegIdx[iCur]);
    sqlite4VdbeChangeP4(v, -1, (const char *)regShort, P4_INT32);

    VdbeComment((v, "key for %s", pIdx->zName));


    /* If Index.onError==OE_None, then pIdx is not a UNIQUE or PRIMARY KEY 
    ** index. In this case there is no need to test the index for uniqueness
    ** - all that is required is to populate the aRegIdx[iCur] register. Jump 
    ** to the next iteration of the loop if this is the case.  */
    onError = pIdx->onError;
    if( onError!=OE_None ){


      int iTest;                  /* Address of OP_IsUnique instruction */

      iTest = sqlite4VdbeAddOp3(v, OP_IsUnique, baseCur+iCur, 0, aRegIdx[iCur]);
      sqlite4VdbeChangeP4(v, -1, (const char *)regShort, P4_INT32);

      /* Figure out what to do if a UNIQUE constraint is encountered. 
      **
      ** TODO: If a previous constraint is a REPLACE, why change IGNORE to
      ** REPLACE and FAIL to ABORT here?  */
      if( overrideError!=OE_Default ){
        onError = overrideError;
      }else if( onError==OE_Default ){
        onError = OE_Abort;
      }
      if( seenReplace ){
        if( onError==OE_Ignore ) onError = OE_Replace;
        else if( onError==OE_Fail ) onError = OE_Abort;
      }
      











      switch( onError ){
        case OE_Rollback:
        case OE_Abort:
        case OE_Fail: {
          int j;
          StrAccum errMsg;
          const char *zSep;
          char *zErr;

          sqlite4StrAccumInit(&errMsg, 0, 0, 200);
          errMsg.db = pParse->db;
          zSep = pIdx->nColumn>1 ? "columns " : "column ";
          for(j=0; j<pIdx->nColumn; j++){

            const char *zCol = indexColumnName(pIdx, j);
            sqlite4StrAccumAppend(&errMsg, zSep, -1);
            zSep = ", ";
            sqlite4StrAccumAppend(&errMsg, zCol, -1);
          }
          sqlite4StrAccumAppend(&errMsg,
              pIdx->nColumn>1 ? " are not unique" : " is not unique", -1);
          zErr = sqlite4StrAccumFinish(&errMsg);
          sqlite4HaltConstraint(pParse, onError, zErr, 0);
          sqlite4DbFree(errMsg.db, zErr);
          break;
        }
        case OE_Ignore: {
          assert( seenReplace==0 );
          sqlite4VdbeAddOp2(v, OP_Goto, 0, ignoreDest);
          break;
        }
        default: {
          assert( 0 );
#if 0
          Trigger *pTrigger = 0;
          assert( onError==OE_Replace );
          sqlite4MultiWrite(pParse);
          if( pParse->db->flags&SQLITE_RecTriggers ){
            pTrigger = sqlite4TriggersExist(pParse, pTab, TK_DELETE, 0, 0);
          }
          sqlite4GenerateRowDelete(
              pParse, pTab, baseCur, regR, 0, pTrigger, OE_Replace
          );
          seenReplace = 1;
#endif
          break;
        }
      }

      /* If the OP_IsUnique passes (no constraint violation) jump here */
      sqlite4VdbeJumpHere(v, iTest);
    }

    sqlite4ReleaseTempRange(pParse, regTmp, nTmpReg);
  }
  
  if( pbMayReplace ){
    *pbMayReplace = seenReplace;
  }
}

/*
** This routine generates code to finish the INSERT or UPDATE operation
** that was started by a prior call to sqlite4GenerateConstraintChecks.



** The arguments to this routine should be the same as the first six
** arguments to sqlite4GenerateConstraintChecks.
**
** Argument regContent points to the first in a contiguous array of 
** registers that contain the row content. This function uses OP_MakeRecord
** to encode them into a record before inserting them into the database.
**
** The array aRegIdx[] contains one entry for each index attached to
** the table, in the same order as the Table.pIndex linked list. If an
** aRegIdx[] entry is 0, this indicates that the entry in the corresponding
** index does not need to be modified. Otherwise, it is the number of
** a register containing the serialized key to insert into the index.
** aRegIdx[0] (the PRIMARY KEY index key) is never 0.
*/
void sqlite4CompleteInsertion(
  Parse *pParse,      /* The parser context */
  Table *pTab,        /* the table into which we are inserting */
  int baseCur,        /* Index of a read/write cursor pointing at pTab */
  int regContent,     /* First register of content */
  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 */
){
  int i;
  Vdbe *v;

  Index *pIdx;
  u8 pik_flags;

  int regRec;

  v = sqlite4GetVdbe(pParse);
  assert( aRegIdx[0] );
  assert( v!=0 );
  assert( pTab->pSelect==0 );  /* This table is not a VIEW */













  if( pParse->nested ){
    pik_flags = 0;
  }else{
    pik_flags = OPFLAG_NCHANGE | (isUpdate?OPFLAG_ISUPDATE:0);
  }

  /* Generate code to serialize array of registers into a database record. */
  regRec = sqlite4GetTempReg(pParse);
  sqlite4VdbeAddOp3(v, OP_MakeRecord, regContent, pTab->nCol, regRec);
  sqlite4TableAffinityStr(v, pTab);
  sqlite4ExprCacheAffinityChange(pParse, regContent, pTab->nCol);

  /* Write the entry to each index. */
  for(i=0, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
    if( aRegIdx[i] ){
      int regData = 0;
      int flags = 0;
      if( pIdx->eIndexType==SQLITE_INDEX_PRIMARYKEY ){
        regData = regRec;
        flags = pik_flags;
      }
      sqlite4VdbeAddOp3(v, OP_IdxInsert, baseCur+i, regData, aRegIdx[i]);
    }
  }
}

/*
** Generate code that will open cursors for a table and for all
** indices of that table.  The "baseCur" parameter is the cursor number used
** for the table.  Indices are opened on subsequent cursors.
**
** Return the number of indices on the table.
*/
int sqlite4OpenAllIndexes(
  Parse *pParse,   /* Parsing context */
  Table *pTab,     /* Table to be opened */
  int baseCur,     /* Cursor number assigned to the table */
  int op           /* OP_OpenRead or OP_OpenWrite */
){
  int i = 0;
  if( IsVirtual(pTab)==0 ){
    int iDb;
    Index *pIdx;

    iDb = sqlite4SchemaToIndex(pParse->db, pTab->pSchema);
    for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
      sqlite4OpenIndex(pParse, baseCur+i, iDb, pIdx, op);
      i++;
    }
    if( pParse->nTab<baseCur+i ){
      pParse->nTab = baseCur+i;
    }
  }
  return i;
}

void sqlite4CloseAllIndexes(
  Parse *pParse,
  Table *pTab,
  int baseCur
){
  int i;
  Index *pIdx;
  Vdbe *v;

  assert( pTab->pIndex==0 || IsVirtual(pTab)==0 );
#ifndef SQLITE_OMIT_VIEW
  assert( pTab->pIndex==0 || pTab->pSelect==0 );
#endif

  v = sqlite4GetVdbe(pParse);


  for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){

    sqlite4VdbeAddOp1(v, OP_Close, baseCur+i);



  }




}


#ifdef SQLITE_TEST
/*
** The following global variable is incremented whenever the
** transfer optimization is used.  This is used for testing

  sqlite4AddDefaultValue(pParse,&v);
}

// In addition to the type name, we also care about the primary key and
// UNIQUE constraints.
//
ccons ::= NULL onconf.
ccons ::= NOT NULL onconf(R).    {sqlite4AddNotNull(pParse, R);}
ccons ::= PRIMARY KEY sortorder(Z) onconf(R) autoinc(I).
                                 {sqlite4AddPrimaryKey(pParse,0,R,I,Z);}
ccons ::= UNIQUE onconf(R).      {sqlite4CreateIndex(pParse,0,0,0,0,R,0,0,0,0);}
ccons ::= CHECK LP expr(X) RP.   {sqlite4AddCheckConstraint(pParse,X.pExpr);}
ccons ::= REFERENCES nm(T) idxlist_opt(TA) refargs(R).
                                 {sqlite4CreateForeignKey(pParse,0,&T,TA,R);}
ccons ::= defer_subclause(D).    {sqlite4DeferForeignKey(pParse,D);}
ccons ::= COLLATE ids(C).        {sqlite4AddCollateType(pParse, &C);}

// The optional AUTOINCREMENT keyword
%type autoinc {int}
autoinc(X) ::= .          {X = 0;}
autoinc(X) ::= AUTOINCR.  {X = 1;}

// The next group of rules parses the arguments to a REFERENCES clause
................................................................................
conslist_opt(A) ::= .                   {A.n = 0; A.z = 0;}
conslist_opt(A) ::= COMMA(X) conslist.  {A = X;}
conslist ::= conslist COMMA tcons.
conslist ::= conslist tcons.
conslist ::= tcons.
tcons ::= CONSTRAINT nm.
tcons ::= PRIMARY KEY LP idxlist(X) autoinc(I) RP onconf(R).
                                 {sqlite4AddPrimaryKey(pParse,X,R,I,0);}
tcons ::= UNIQUE LP idxlist(X) RP onconf(R).
                                 {sqlite4CreateIndex(pParse,0,0,0,X,R,0,0,0,0);}
tcons ::= CHECK LP expr(E) RP onconf.
                                 {sqlite4AddCheckConstraint(pParse,E.pExpr);}
tcons ::= FOREIGN KEY LP idxlist(FA) RP
          REFERENCES nm(T) idxlist_opt(TA) refargs(R) defer_subclause_opt(D). {
    sqlite4CreateForeignKey(pParse, FA, &T, TA, R);
    sqlite4DeferForeignKey(pParse, D);
}
%type defer_subclause_opt {int}
defer_subclause_opt(A) ::= .                    {A = 0;}
................................................................................

///////////////////////////// The CREATE INDEX command ///////////////////////
//
cmd ::= createkw(S) uniqueflag(U) INDEX ifnotexists(NE) nm(X) dbnm(D)
        ON nm(Y) LP idxlist(Z) RP(E). {
  sqlite4CreateIndex(pParse, &X, &D, 
                     sqlite4SrcListAppend(pParse->db,0,&Y,0), Z, U,
                      &S, &E, SQLITE_SO_ASC, NE);
}

%type uniqueflag {int}
uniqueflag(A) ::= UNIQUE.  {A = OE_Abort;}
uniqueflag(A) ::= .        {A = OE_None;}

%type idxlist {ExprList*}

  sqlite4AddDefaultValue(pParse,&v);
}

// In addition to the type name, we also care about the primary key and
// UNIQUE constraints.
//
ccons ::= NULL onconf.
ccons ::= NOT NULL onconf(R).  {sqlite4AddNotNull(pParse, R);}
ccons ::= PRIMARY KEY sortorder(Z) onconf(R) autoinc(I).
                               {sqlite4AddPrimaryKey(pParse,0,R,I,Z);}
ccons ::= UNIQUE onconf(R).    {sqlite4CreateIndex(pParse,0,0,0,0,R,0,0,0,0,0);}
ccons ::= CHECK LP expr(X) RP. {sqlite4AddCheckConstraint(pParse,X.pExpr);}
ccons ::= REFERENCES nm(T) idxlist_opt(TA) refargs(R).
                               {sqlite4CreateForeignKey(pParse,0,&T,TA,R);}
ccons ::= defer_subclause(D).  {sqlite4DeferForeignKey(pParse,D);}
ccons ::= COLLATE ids(C).      {sqlite4AddCollateType(pParse, &C);}

// The optional AUTOINCREMENT keyword
%type autoinc {int}
autoinc(X) ::= .          {X = 0;}
autoinc(X) ::= AUTOINCR.  {X = 1;}

// The next group of rules parses the arguments to a REFERENCES clause
................................................................................
conslist_opt(A) ::= .                   {A.n = 0; A.z = 0;}
conslist_opt(A) ::= COMMA(X) conslist.  {A = X;}
conslist ::= conslist COMMA tcons.
conslist ::= conslist tcons.
conslist ::= tcons.
tcons ::= CONSTRAINT nm.
tcons ::= PRIMARY KEY LP idxlist(X) autoinc(I) RP onconf(R).
                             {sqlite4AddPrimaryKey(pParse,X,R,I,0);}
tcons ::= UNIQUE LP idxlist(X) RP onconf(R).
                             {sqlite4CreateIndex(pParse,0,0,0,X,R,0,0,0,0,0);}
tcons ::= CHECK LP expr(E) RP onconf.
                             {sqlite4AddCheckConstraint(pParse,E.pExpr);}
tcons ::= FOREIGN KEY LP idxlist(FA) RP
          REFERENCES nm(T) idxlist_opt(TA) refargs(R) defer_subclause_opt(D). {
    sqlite4CreateForeignKey(pParse, FA, &T, TA, R);
    sqlite4DeferForeignKey(pParse, D);
}
%type defer_subclause_opt {int}
defer_subclause_opt(A) ::= .                    {A = 0;}
................................................................................

///////////////////////////// The CREATE INDEX command ///////////////////////
//
cmd ::= createkw(S) uniqueflag(U) INDEX ifnotexists(NE) nm(X) dbnm(D)
        ON nm(Y) LP idxlist(Z) RP(E). {
  sqlite4CreateIndex(pParse, &X, &D, 
                     sqlite4SrcListAppend(pParse->db,0,&Y,0), Z, U,
                      &S, &E, SQLITE_SO_ASC, NE, 0);
}

%type uniqueflag {int}
uniqueflag(A) ::= UNIQUE.  {A = OE_Abort;}
uniqueflag(A) ::= .        {A = OE_None;}

%type idxlist {ExprList*}

  **
  ** Print an ascii rendering of the complete content of the database file.
  */
  if( sqlite4StrICmp(zLeft, "kvdump")==0 ){
    sqlite4KVStoreDump(db->aDb[0].pKV);
  }else
#endif /* SQLITE_OMIT_COMPILEOPTION_DIAGS */































































































































































  /*
  **  PRAGMA shrink_memory
  **
  ** This pragma attempts to free as much memory as possible from the
  ** current database connection.

  **
  ** Print an ascii rendering of the complete content of the database file.
  */
  if( sqlite4StrICmp(zLeft, "kvdump")==0 ){
    sqlite4KVStoreDump(db->aDb[0].pKV);
  }else
#endif /* SQLITE_OMIT_COMPILEOPTION_DIAGS */
  /*
  **   PRAGMA integrity_check
  **
  ** Check that for each table, the content of any auxilliary indexes are 
  ** consistent with the primary key index.
  */
  if( sqlite4StrICmp(zLeft, "integrity_check")==0 ){
    const int baseCsr = 1;        /* Base cursor for OpenAllIndexes() call */

    const int regErrcnt = 1;      /* Register containing error count */
    const int regErrstr = 2;      /* Register containing error string */
    const int regTmp = 3;         /* Register for tmp use */
    const int regRowcnt1 = 4;     /* Register containing row count (from PK) */
    const int regRowcnt2 = 5;     /* Register containing error count */
    const int regResult = 6;      /* Register containing result string */
    const int regKey = 7;         /* Register containing encoded key */
    const int regArray = 8;       /* First in array of registers */

    int i;
    int nMaxArray = 1;
    int addrNot = 0;
    Vdbe *v;

    if( sqlite4ReadSchema(pParse) ) goto pragma_out;

    for(i=0; i<db->nDb; i++){
      if( OMIT_TEMPDB && i==1 ) continue;
      sqlite4CodeVerifySchema(pParse, i);
    }

    v = sqlite4GetVdbe(pParse);
    sqlite4VdbeAddOp2(v, OP_Integer, 0, regErrcnt);
    sqlite4VdbeAddOp4(v, OP_String8, 0, regErrstr, 0, "", 0);

    for(i=0; i<db->nDb; i++){
      Hash *pTbls;
      HashElem *x;

      if( OMIT_TEMPDB && i==1 ) continue;

      pTbls = &db->aDb[i].pSchema->tblHash;
      for(x=sqliteHashFirst(pTbls); x; x=sqliteHashNext(x)){
        Index *pIdx;
        Table *pTab = (Table *)sqliteHashData(x);
        int addrRewind;
        int nIdx = 0;
        int iPkCsr;
        Index *pPk;
        int iCsr;

        /* Open all indexes for table pTab. */
        for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
          if( pIdx->eIndexType==SQLITE_INDEX_PRIMARYKEY ){
            pPk = pIdx;
            iPkCsr = nIdx+baseCsr;
          }
          nIdx++;
        }
        sqlite4OpenAllIndexes(pParse, pTab, baseCsr, OP_OpenRead);

        sqlite4VdbeAddOp2(v, OP_Integer, 0, regRowcnt1);
        addrRewind = sqlite4VdbeAddOp1(v, OP_Rewind, iPkCsr);

        /* Increment the row-count register */
        sqlite4VdbeAddOp2(v, OP_AddImm, regRowcnt1, 1);

        for(iCsr=baseCsr, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, iCsr++){
          assert( (pIdx->eIndexType==SQLITE_INDEX_PRIMARYKEY)==(iCsr==iPkCsr) );
          if( iCsr!=iPkCsr ){
            char *zErr;
            int iCol;
            int jmp;
            for(iCol=0; iCol<pIdx->nColumn; iCol++){
              int r = regArray + iCol;
              sqlite4VdbeAddOp3(v, OP_Column, iPkCsr, pIdx->aiColumn[iCol], r);
              assert( pIdx->aiColumn[iCol]>=0 );
            }
            for(iCol=0; iCol<pPk->nColumn; iCol++){
              int reg = regArray + pIdx->nColumn + iCol;
              int iTblCol = pPk->aiColumn[iCol];
              if( iTblCol<0 ){
                sqlite4VdbeAddOp2(v, OP_Rowid, iPkCsr, reg);
              }else{
                sqlite4VdbeAddOp3(v, OP_Column, iPkCsr, iTblCol, reg);
              }
            }

            if( (pPk->nColumn+pIdx->nColumn)>nMaxArray ){
              nMaxArray = pPk->nColumn + pIdx->nColumn;
            }

            sqlite4VdbeAddOp3(v, OP_MakeIdxKey, iCsr, regArray, regKey);
            jmp = sqlite4VdbeAddOp4(v, OP_Found, iCsr, 0, regKey, 0, P4_INT32);
            sqlite4VdbeAddOp2(v, OP_AddImm, regErrcnt, 1);
            zErr = sqlite4MPrintf(
                db, "entry missing from index %s: ", pIdx->zName
            );
            sqlite4VdbeAddOp4(v, OP_String8, 0, regTmp, 0, zErr, 0);
            sqlite4VdbeAddOp3(v, OP_Concat, regTmp, regErrstr, regErrstr);
            sqlite4VdbeAddOp3(v, OP_Function, 0, regKey, regTmp);
            sqlite4VdbeChangeP4(v, -1,
                (char *)sqlite4FindFunction(db, "hex", 3, 1, SQLITE_UTF8, 0), 
                P4_FUNCDEF
            );
            sqlite4VdbeChangeP5(v, 1);
            sqlite4VdbeAddOp3(v, OP_Concat, regTmp, regErrstr, regErrstr);
            sqlite4VdbeAddOp4(v, OP_String8, 0, regTmp, 0, "\n", 0);
            sqlite4VdbeAddOp3(v, OP_Concat, regTmp, regErrstr, regErrstr);
            sqlite4VdbeJumpHere(v, jmp);
            sqlite4DbFree(db, zErr);
          }
        }
        sqlite4VdbeAddOp2(v, OP_Next, iPkCsr, addrRewind+1);
        sqlite4VdbeJumpHere(v, addrRewind);

        for(iCsr=baseCsr, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, iCsr++){
          if( iCsr!=iPkCsr ){
            char *zErr;
            int addrEq;
            int addrRewind2;
            sqlite4VdbeAddOp2(v, OP_Integer, 0, regRowcnt2);
            addrRewind2 = sqlite4VdbeAddOp1(v, OP_Rewind, iCsr);
            sqlite4VdbeAddOp2(v, OP_AddImm, regRowcnt2, 1);
            sqlite4VdbeAddOp2(v, OP_Next, iCsr, addrRewind2+1);
            sqlite4VdbeJumpHere(v, addrRewind2);
            zErr = sqlite4MPrintf(
                db, "wrong # number of entries in index %s\n", pIdx->zName
            );
            addrEq = sqlite4VdbeAddOp3(v, OP_Eq, regRowcnt1, 0, regRowcnt2);
            sqlite4VdbeAddOp2(v, OP_AddImm, regErrcnt, 1);
            sqlite4VdbeAddOp4(v, OP_String8, 0, regTmp, 0, zErr, 0);
            sqlite4VdbeAddOp3(v, OP_Concat, regTmp, regErrstr, regErrstr);

            sqlite4VdbeJumpHere(v, addrEq);
            sqlite4DbFree(db, zErr);
          }
        }

        for(iCsr=baseCsr; iCsr<(baseCsr+nIdx); iCsr++){
          sqlite4VdbeAddOp1(v, OP_Close, iCsr);
        }
      }
    }

    sqlite4VdbeAddOp4(v, OP_String8, 0, regResult, 0, "ok", 0);
    addrNot = sqlite4VdbeAddOp1(v, OP_IfNot, regErrcnt);
    sqlite4VdbeAddOp4(v, OP_String8, 0, regArray, 0, " errors:\n", 0);
    sqlite4VdbeAddOp3(v, OP_Concat, regArray, regErrcnt, regResult);
    sqlite4VdbeAddOp3(v, OP_Concat, regErrstr, regResult, regResult);
    sqlite4VdbeJumpHere(v, addrNot);

    pParse->nMem = (regArray + nMaxArray);
    sqlite4VdbeSetNumCols(v, 1);
    sqlite4VdbeSetColName(v, 0, COLNAME_NAME, "integrity_check", SQLITE_STATIC);
    sqlite4VdbeAddOp2(v, OP_ResultRow, regResult, 1);

  }else


  /*
  **  PRAGMA shrink_memory
  **
  ** This pragma attempts to free as much memory as possible from the
  ** current database connection.

      p = p->pLeft;
    }else{
      return 1;
    }
  }
  return 0;
}

      p = p->pLeft;
    }else{
      return 1;
    }
  }
  return 0;
}

typedef struct KeySetEntry KeySetEntry;

struct KeySetEntry {
  char *z;
  int n;
  KeySetEntry *pNext;
};

struct KeySet {
  sqlite4 *db;                    /* Database handle for sqlite4DbMalloc() */
  KeySetEntry *pFirst;
  KeySetEntry *pLast;
};

KeySet *sqlite4KeySetInit(sqlite4 *db){
  KeySet *pRet;
  pRet = (KeySet *)sqlite4DbMallocZero(db, sizeof(KeySet));
  if( pRet ){
    pRet->db = db;
  }
  return pRet;
}

void sqlite4KeySetInsert(KeySet *pKeySet, const char *z, int n){
  KeySetEntry *pNew;
  int nByte = n + sizeof(KeySetEntry);

  pNew = (KeySetEntry *)sqlite4DbMallocZero(pKeySet->db, nByte);
  if( pNew ){
    pNew->z = (char *)&pNew[1];
    pNew->n =n;
    memcpy(pNew->z, z, n);
    if( pKeySet->pFirst ){
      pKeySet->pLast = pKeySet->pLast->pNext = pNew;
    }else{
      pKeySet->pLast = pKeySet->pFirst = pNew;
    }
  }
}

/*
** Read the blob of data stored in the current key-set entry.
*/
const char *sqlite4KeySetRead(KeySet *pKeySet, int *pn){
  const char *pRet;
  if( pKeySet->pFirst ){
    *pn = pKeySet->pFirst->n;
    pRet = pKeySet->pFirst->z;
  }else{
    pRet = 0;
    *pn = 0;
  }
  return pRet;
}

int sqlite4KeySetNext(KeySet *pKeySet){
  KeySetEntry *pFirst = pKeySet->pFirst->pNext;
  sqlite4DbFree(pKeySet->db, pKeySet->pFirst);
  pKeySet->pFirst = pFirst;
  return (pFirst!=0);
}

void sqlite4KeySetFree(KeySet *pKeySet){
  while( pKeySet->pFirst ){
    sqlite4KeySetNext(pKeySet);
  }
  sqlite4DbFree(pKeySet->db, pKeySet);
}

typedef struct FuncDef FuncDef;
typedef struct FuncDefHash FuncDefHash;
typedef struct IdList IdList;
typedef struct Index Index;
typedef struct IndexSample IndexSample;
typedef struct KeyClass KeyClass;
typedef struct KeyInfo KeyInfo;

typedef struct Lookaside Lookaside;
typedef struct LookasideSlot LookasideSlot;
typedef struct Module Module;
typedef struct NameContext NameContext;
typedef struct Parse Parse;
typedef struct RowSet RowSet;
typedef struct Savepoint Savepoint;
................................................................................
typedef struct UnpackedRecord UnpackedRecord;
typedef struct VTable VTable;
typedef struct VtabCtx VtabCtx;
typedef struct Walker Walker;
typedef struct WherePlan WherePlan;
typedef struct WhereInfo WhereInfo;
typedef struct WhereLevel WhereLevel;


/*
** Defer sourcing vdbe.h until after the "u8" and 
** "BusyHandler" typedefs. vdbe.h also requires a few of the opaque
** pointer types (i.e. FuncDef) defined above.
*/
#include "vdbe.h"
................................................................................
*/
struct Table {
  char *zName;         /* Name of the table or view */
  int iPKey;           /* If not negative, use aCol[iPKey] as the primary key */
  int nCol;            /* Number of columns in this table */
  Column *aCol;        /* Information about each column */
  Index *pIndex;       /* List of SQL indexes on this table. */

  int tnum;            /* Root BTree node for this table (see note above) */

  tRowcnt nRowEst;     /* Estimated rows in table - from sqlite_stat1 table */
  Select *pSelect;     /* NULL for tables.  Points to definition if a view. */
  u16 nRef;            /* Number of pointers to this Table */
  u8 tabFlags;         /* Mask of TF_* values */
  u8 keyConf;          /* What to do in case of uniqueness conflict on iPKey */
  FKey *pFKey;         /* Linked list of all foreign keys in this table */
  char *zColAff;       /* String defining the affinity of each column */
................................................................................
** each key, and the number of primary key fields appended to the end.
*/
struct KeyInfo {
  sqlite4 *db;        /* The database connection */
  u8 enc;             /* Text encoding - one of the SQLITE_UTF* values */
  u16 nField;         /* Total number of entries in aColl[] */
  u16 nPK;            /* Number of primary key entries at the end of aColl[] */

  u8 *aSortOrder;     /* Sort order for each column.  May be NULL */
  CollSeq *aColl[1];  /* Collating sequence for each term of the key */
};

/*
** An instance of the following structure holds information about a
** single index record that has already been parsed out into individual
................................................................................
  char *zName;     /* Name of this index */
  int nColumn;     /* Number of columns in the table used by this index */
  int *aiColumn;   /* Which columns are used by this index.  1st is 0 */
  tRowcnt *aiRowEst; /* Result of ANALYZE: Est. rows selected by each column */
  Table *pTable;   /* The SQL table being indexed */
  int tnum;        /* Page containing root of this index in database file */
  u8 onError;      /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
  u8 autoIndex;    /* True if is automatically created (ex: by UNIQUE) */
  u8 bUnordered;   /* Use this index for == or IN queries only */
  char *zColAff;   /* String defining the affinity of each column */
  Index *pNext;    /* The next index associated with the same table */
  Schema *pSchema; /* Schema containing this index */
  u8 *aSortOrder;  /* Array of size Index.nColumn. True==DESC, False==ASC */
  char **azColl;   /* Array of collation sequence names for index */
#ifdef SQLITE_ENABLE_STAT3
  int nSample;             /* Number of elements in aSample[] */
  tRowcnt avgEq;           /* Average nEq value for key values not in aSample */
  IndexSample *aSample;    /* Samples of the left-most key */
#endif
};






/*
** Each sample stored in the sqlite_stat3 table is represented in memory 
** using a structure of this type.  See documentation at the top of the
** analyze.c source file for additional information.
*/
struct IndexSample {
  union {
................................................................................
  int cookieGoto;      /* Address of OP_Goto to cookie verifier subroutine */
  int cookieValue[SQLITE_MAX_ATTACHED+2];  /* Values of cookies to verify */
#ifndef SQLITE_OMIT_SHARED_CACHE
  int nTableLock;        /* Number of locks in aTableLock */
  TableLock *aTableLock; /* Required table locks for shared-cache mode */
#endif
  int regRowid;        /* Register holding rowid of CREATE TABLE entry */

  int regRoot;         /* Register holding root page number for new objects */

  AutoincInfo *pAinc;  /* Information about AUTOINCREMENT counters */
  int nMaxArg;         /* Max args passed to user function by sub-program */

  /* Information used while coding trigger programs. */
  Parse *pToplevel;    /* Parse structure for main program (or NULL) */
  Table *pTriggerTab;  /* Table triggers are being coded for */
  u32 oldmask;         /* Mask of old.* columns referenced */
................................................................................
int sqlite4BitvecBuiltinTest(int,int*);

RowSet *sqlite4RowSetInit(sqlite4*, void*, unsigned int);
void sqlite4RowSetClear(RowSet*);
void sqlite4RowSetInsert(RowSet*, i64);
int sqlite4RowSetTest(RowSet*, u8 iBatch, i64);
int sqlite4RowSetNext(RowSet*, i64*);







void sqlite4CreateView(Parse*,Token*,Token*,Token*,Select*,int,int);

#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
  int sqlite4ViewGetColumnNames(Parse*,Table*);
#else
# define sqlite4ViewGetColumnNames(A,B) 0
................................................................................
void sqlite4SrcListIndexedBy(Parse *, SrcList *, Token *);
int sqlite4IndexedByLookup(Parse *, struct SrcList_item *);
void sqlite4SrcListShiftJoinType(SrcList*);
void sqlite4SrcListAssignCursors(Parse*, SrcList*);
void sqlite4IdListDelete(sqlite4*, IdList*);
void sqlite4SrcListDelete(sqlite4*, SrcList*);
Index *sqlite4CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
                        Token*, int, int);
void sqlite4DropIndex(Parse*, SrcList*, int);
int sqlite4Select(Parse*, Select*, SelectDest*);
Select *sqlite4SelectNew(Parse*,ExprList*,SrcList*,Expr*,ExprList*,
                         Expr*,ExprList*,int,Expr*,Expr*);
void sqlite4SelectDelete(sqlite4*, Select*);
Table *sqlite4SrcListLookup(Parse*, SrcList*);
int sqlite4IsReadOnly(Parse*, Table*, int);
................................................................................
void sqlite4StrAccumInit(StrAccum*, char*, int, int);
void sqlite4StrAccumAppend(StrAccum*,const char*,int);
void sqlite4AppendSpace(StrAccum*,int);
char *sqlite4StrAccumFinish(StrAccum*);
void sqlite4StrAccumReset(StrAccum*);
void sqlite4SelectDestInit(SelectDest*,int,int);
Expr *sqlite4CreateColumnExpr(sqlite4 *, SrcList *, int, int);







/*
** The interface to the LEMON-generated parser
*/
void *sqlite4ParserAlloc(void*(*)(size_t));
void sqlite4ParserFree(void*, void(*)(void*));
void sqlite4Parser(void*, int, Token, Parse*);

typedef struct FuncDef FuncDef;
typedef struct FuncDefHash FuncDefHash;
typedef struct IdList IdList;
typedef struct Index Index;
typedef struct IndexSample IndexSample;
typedef struct KeyClass KeyClass;
typedef struct KeyInfo KeyInfo;
typedef struct KeySet KeySet;
typedef struct Lookaside Lookaside;
typedef struct LookasideSlot LookasideSlot;
typedef struct Module Module;
typedef struct NameContext NameContext;
typedef struct Parse Parse;
typedef struct RowSet RowSet;
typedef struct Savepoint Savepoint;
................................................................................
typedef struct UnpackedRecord UnpackedRecord;
typedef struct VTable VTable;
typedef struct VtabCtx VtabCtx;
typedef struct Walker Walker;
typedef struct WherePlan WherePlan;
typedef struct WhereInfo WhereInfo;
typedef struct WhereLevel WhereLevel;


/*
** Defer sourcing vdbe.h until after the "u8" and 
** "BusyHandler" typedefs. vdbe.h also requires a few of the opaque
** pointer types (i.e. FuncDef) defined above.
*/
#include "vdbe.h"
................................................................................
*/
struct Table {
  char *zName;         /* Name of the table or view */
  int iPKey;           /* If not negative, use aCol[iPKey] as the primary key */
  int nCol;            /* Number of columns in this table */
  Column *aCol;        /* Information about each column */
  Index *pIndex;       /* List of SQL indexes on this table. */
#if 0
  int tnum;            /* Root BTree node for this table (see note above) */
#endif
  tRowcnt nRowEst;     /* Estimated rows in table - from sqlite_stat1 table */
  Select *pSelect;     /* NULL for tables.  Points to definition if a view. */
  u16 nRef;            /* Number of pointers to this Table */
  u8 tabFlags;         /* Mask of TF_* values */
  u8 keyConf;          /* What to do in case of uniqueness conflict on iPKey */
  FKey *pFKey;         /* Linked list of all foreign keys in this table */
  char *zColAff;       /* String defining the affinity of each column */
................................................................................
** each key, and the number of primary key fields appended to the end.
*/
struct KeyInfo {
  sqlite4 *db;        /* The database connection */
  u8 enc;             /* Text encoding - one of the SQLITE_UTF* values */
  u16 nField;         /* Total number of entries in aColl[] */
  u16 nPK;            /* Number of primary key entries at the end of aColl[] */
  u16 nData;          /* Number of columns of data in KV entry value */
  u8 *aSortOrder;     /* Sort order for each column.  May be NULL */
  CollSeq *aColl[1];  /* Collating sequence for each term of the key */
};

/*
** An instance of the following structure holds information about a
** single index record that has already been parsed out into individual
................................................................................
  char *zName;     /* Name of this index */
  int nColumn;     /* Number of columns in the table used by this index */
  int *aiColumn;   /* Which columns are used by this index.  1st is 0 */
  tRowcnt *aiRowEst; /* Result of ANALYZE: Est. rows selected by each column */
  Table *pTable;   /* The SQL table being indexed */
  int tnum;        /* Page containing root of this index in database file */
  u8 onError;      /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
  u8 eIndexType;   /* SQLITE_INDEX_USER, UNIQUE or PRIMARYKEY */
  u8 bUnordered;   /* Use this index for == or IN queries only */
  char *zColAff;   /* String defining the affinity of each column */
  Index *pNext;    /* The next index associated with the same table */
  Schema *pSchema; /* Schema containing this index */
  u8 *aSortOrder;  /* Array of size Index.nColumn. True==DESC, False==ASC */
  char **azColl;   /* Array of collation sequence names for index */
#ifdef SQLITE_ENABLE_STAT3
  int nSample;             /* Number of elements in aSample[] */
  tRowcnt avgEq;           /* Average nEq value for key values not in aSample */
  IndexSample *aSample;    /* Samples of the left-most key */
#endif
};

/* Index.eIndexType must be set to one of the following. */
#define SQLITE_INDEX_USER       0 /* Index created by CREATE INDEX statement */
#define SQLITE_INDEX_UNIQUE     1 /* Index created by UNIQUE constraint */
#define SQLITE_INDEX_PRIMARYKEY 2 /* Index is the tables PRIMARY KEY */

/*
** Each sample stored in the sqlite_stat3 table is represented in memory 
** using a structure of this type.  See documentation at the top of the
** analyze.c source file for additional information.
*/
struct IndexSample {
  union {
................................................................................
  int cookieGoto;      /* Address of OP_Goto to cookie verifier subroutine */
  int cookieValue[SQLITE_MAX_ATTACHED+2];  /* Values of cookies to verify */
#ifndef SQLITE_OMIT_SHARED_CACHE
  int nTableLock;        /* Number of locks in aTableLock */
  TableLock *aTableLock; /* Required table locks for shared-cache mode */
#endif
  int regRowid;        /* Register holding rowid of CREATE TABLE entry */
#if 0
  int regRoot;         /* Register holding root page number for new objects */
#endif
  AutoincInfo *pAinc;  /* Information about AUTOINCREMENT counters */
  int nMaxArg;         /* Max args passed to user function by sub-program */

  /* Information used while coding trigger programs. */
  Parse *pToplevel;    /* Parse structure for main program (or NULL) */
  Table *pTriggerTab;  /* Table triggers are being coded for */
  u32 oldmask;         /* Mask of old.* columns referenced */
................................................................................
int sqlite4BitvecBuiltinTest(int,int*);

RowSet *sqlite4RowSetInit(sqlite4*, void*, unsigned int);
void sqlite4RowSetClear(RowSet*);
void sqlite4RowSetInsert(RowSet*, i64);
int sqlite4RowSetTest(RowSet*, u8 iBatch, i64);
int sqlite4RowSetNext(RowSet*, i64*);

KeySet *sqlite4KeySetInit(sqlite4*);
void sqlite4KeySetInsert(KeySet *, const char *, int);
const char *sqlite4KeySetRead(KeySet *, int *);
int sqlite4KeySetNext(KeySet *);
void sqlite4KeySetFree(KeySet *);

void sqlite4CreateView(Parse*,Token*,Token*,Token*,Select*,int,int);

#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
  int sqlite4ViewGetColumnNames(Parse*,Table*);
#else
# define sqlite4ViewGetColumnNames(A,B) 0
................................................................................
void sqlite4SrcListIndexedBy(Parse *, SrcList *, Token *);
int sqlite4IndexedByLookup(Parse *, struct SrcList_item *);
void sqlite4SrcListShiftJoinType(SrcList*);
void sqlite4SrcListAssignCursors(Parse*, SrcList*);
void sqlite4IdListDelete(sqlite4*, IdList*);
void sqlite4SrcListDelete(sqlite4*, SrcList*);
Index *sqlite4CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
                        Token*, int, int, int);
void sqlite4DropIndex(Parse*, SrcList*, int);
int sqlite4Select(Parse*, Select*, SelectDest*);
Select *sqlite4SelectNew(Parse*,ExprList*,SrcList*,Expr*,ExprList*,
                         Expr*,ExprList*,int,Expr*,Expr*);
void sqlite4SelectDelete(sqlite4*, Select*);
Table *sqlite4SrcListLookup(Parse*, SrcList*);
int sqlite4IsReadOnly(Parse*, Table*, int);
................................................................................
void sqlite4StrAccumInit(StrAccum*, char*, int, int);
void sqlite4StrAccumAppend(StrAccum*,const char*,int);
void sqlite4AppendSpace(StrAccum*,int);
char *sqlite4StrAccumFinish(StrAccum*);
void sqlite4StrAccumReset(StrAccum*);
void sqlite4SelectDestInit(SelectDest*,int,int);
Expr *sqlite4CreateColumnExpr(sqlite4 *, SrcList *, int, int);

void sqlite4OpenPrimaryKey(Parse*, int iCur, int iDb, Table*, int);
void sqlite4OpenIndex(Parse*, int iCur, int iDb, Index*, int);
int sqlite4OpenAllIndexes(Parse *, Table *, int, int);
void sqlite4CloseAllIndexes(Parse *, Table *, int);
Index *sqlite4FindPrimaryKey(Table *, int *);

/*
** The interface to the LEMON-generated parser
*/
void *sqlite4ParserAlloc(void*(*)(size_t));
void sqlite4ParserFree(void*, void(*)(void*));
void sqlite4Parser(void*, int, Token, Parse*);

}

/*
** Process an UPDATE statement.
**
**   UPDATE OR IGNORE table_wxyz SET a=b, c=d WHERE e<5 AND f NOT NULL;
**          \_______/ \________/     \______/       \________________/
*            onError   pTabList      pChanges             pWhere
*/
void sqlite4Update(
  Parse *pParse,         /* The parser context */
  SrcList *pTabList,     /* The table in which we should change things */
  ExprList *pChanges,    /* Things to be changed */
  Expr *pWhere,          /* The WHERE clause.  May be null */
  int onError            /* How to handle constraint errors */
){
  int i, j;              /* Loop counters */
  Table *pTab;           /* The table to be updated */
  int addr = 0;          /* VDBE instruction address of the start of the loop */
................................................................................
  sqlite4 *db;           /* The database structure */
  int *aRegIdx = 0;      /* One register assigned to each index to be updated */
  int *aXRef = 0;        /* aXRef[i] is the index in pChanges->a[] of the
                         ** an expression for the i-th column of the table.
                         ** aXRef[i]==-1 if the i-th column is not changed. */
  int chngRowid;         /* True if the record number is being changed */
  Expr *pRowidExpr = 0;  /* Expression defining the new record number */
  int openAll = 0;       /* True if all indices need to be opened */
  AuthContext sContext;  /* The authorization context */
  NameContext sNC;       /* The name-context to resolve expressions in */
  int iDb;               /* Database containing the table being updated */
  int okOnePass;         /* True for one-pass algorithm without the FIFO */
  int hasFK;             /* True if foreign key processing is required */

#ifndef SQLITE_OMIT_TRIGGER
................................................................................
  int isView;            /* True when updating a view (INSTEAD OF trigger) */
  Trigger *pTrigger;     /* List of triggers on pTab, if required */
  int tmask;             /* Mask of TRIGGER_BEFORE|TRIGGER_AFTER */
#endif
  int newmask;           /* Mask of NEW.* columns accessed by BEFORE triggers */

  /* Register Allocations */


  int regRowCount = 0;   /* A count of rows changed */
  int regOldRowid;       /* The old rowid */
  int regNewRowid;       /* The new rowid */
  int regNew;            /* Content of the NEW.* table in triggers */
  int regOld = 0;        /* Content of OLD.* table in triggers */
  int regRowSet = 0;     /* Rowset of rows to be updated */







  memset(&sContext, 0, sizeof(sContext));
  db = pParse->db;
  if( pParse->nErr || db->mallocFailed ){
    goto update_cleanup;
  }
  assert( pTabList->nSrc==1 );

  /* Locate the table which we want to update. 
  */
  pTab = sqlite4SrcListLookup(pParse, pTabList);
  if( pTab==0 ) goto update_cleanup;
  iDb = sqlite4SchemaToIndex(pParse->db, pTab->pSchema);


  /* Figure out if we have any triggers and if the table being
  ** updated is a view.
  */
#ifndef SQLITE_OMIT_TRIGGER
  pTrigger = sqlite4TriggersExist(pParse, pTab, TK_UPDATE, pChanges, &tmask);
  isView = pTab->pSelect!=0;
................................................................................
  for(i=0; i<pTab->nCol; i++) aXRef[i] = -1;

  /* Allocate a cursors for the main database table and for all indices.
  ** The index cursors might not be used, but if they are used they
  ** need to occur right after the database cursor.  So go ahead and
  ** allocate enough space, just in case.
  */
  pTabList->a[0].iCursor = iCur = pParse->nTab++;
  for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
    pParse->nTab++;
  }

  /* Initialize the name-context */
  memset(&sNC, 0, sizeof(sNC));
  sNC.pParse = pParse;
  sNC.pSrcList = pTabList;

  /* Resolve the column names in all the expressions of the
  ** of the UPDATE statement.  Also find the column index
  ** for each column to be updated in the pChanges array.  For each
  ** column to be updated, make sure we have authorization to change
  ** that column.
  */

  chngRowid = 0;


  for(i=0; i<pChanges->nExpr; i++){



    if( sqlite4ResolveExprNames(&sNC, pChanges->a[i].pExpr) ){
      goto update_cleanup;
    }


    for(j=0; j<pTab->nCol; j++){
      if( sqlite4StrICmp(pTab->aCol[j].zName, pChanges->a[i].zName)==0 ){
        if( j==pTab->iPKey ){
          chngRowid = 1;
          pRowidExpr = pChanges->a[i].pExpr;
        }
        aXRef[j] = i;
        break;
      }
    }
    if( j>=pTab->nCol ){
      if( sqlite4IsRowid(pChanges->a[i].zName) ){
        chngRowid = 1;
        pRowidExpr = pChanges->a[i].pExpr;
      }else{
        sqlite4ErrorMsg(pParse, "no such column: %s", pChanges->a[i].zName);
        pParse->checkSchema = 1;
        goto update_cleanup;
      }

    }





#ifndef SQLITE_OMIT_AUTHORIZATION
    {
      int rc;
      rc = sqlite4AuthCheck(pParse, SQLITE_UPDATE, pTab->zName,
                           pTab->aCol[j].zName, db->aDb[iDb].zName);
      if( rc==SQLITE_DENY ){
        goto update_cleanup;
................................................................................
      }else if( rc==SQLITE_IGNORE ){
        aXRef[j] = -1;
      }
    }
#endif
  }

  hasFK = sqlite4FkRequired(pParse, pTab, aXRef, chngRowid);

  /* Allocate memory for the array aRegIdx[].  There is one entry in the
  ** array for each index associated with table being updated.  Fill in
  ** the value with a register number for indices that are to be used
  ** and with zero for unused indices.
  */
  for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){}
  if( nIdx>0 ){
    aRegIdx = sqlite4DbMallocRaw(db, sizeof(Index*) * nIdx );
    if( aRegIdx==0 ) goto update_cleanup;
  }
  for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
    int reg;
    if( hasFK || chngRowid ){
      reg = ++pParse->nMem;  /* Register for index key */
      pParse->nMem++;        /* Extra register for index data */
    }else{
      reg = 0;
      for(i=0; i<pIdx->nColumn; i++){
        if( aXRef[pIdx->aiColumn[i]]>=0 ){
          reg = ++pParse->nMem;
          break;
        }
      }
    }
    aRegIdx[j] = reg;
  }

  /* Begin generating code. */
  v = sqlite4GetVdbe(pParse);
  if( v==0 ) goto update_cleanup;
  if( pParse->nested==0 ) sqlite4VdbeCountChanges(v);
  sqlite4BeginWriteOperation(pParse, 1, iDb);

#ifndef SQLITE_OMIT_VIRTUALTABLE
  /* Virtual tables must be handled separately */
  if( IsVirtual(pTab) ){
    updateVirtualTable(pParse, pTabList, pTab, pChanges, pRowidExpr, aXRef,
                       pWhere, onError);
    pWhere = 0;
    pTabList = 0;
    goto update_cleanup;
  }
#endif

























  /* Allocate required registers. */
  regRowSet = ++pParse->nMem;
  regOldRowid = regNewRowid = ++pParse->nMem;
  if( pTrigger || hasFK ){
    regOld = pParse->nMem + 1;
    pParse->nMem += pTab->nCol;
  }
  if( chngRowid || pTrigger || hasFK ){
    regNewRowid = ++pParse->nMem;
  }
................................................................................
  /* Resolve the column names in all the expressions in the
  ** WHERE clause.
  */
  if( sqlite4ResolveExprNames(&sNC, pWhere) ){
    goto update_cleanup;
  }

  /* Begin the database scan
  */
  sqlite4VdbeAddOp3(v, OP_Null, 0, regRowSet, regOldRowid);
  pWInfo = sqlite4WhereBegin(
      pParse, pTabList, pWhere, 0, 0, WHERE_ONEPASS_DESIRED
  );
  if( pWInfo==0 ) goto update_cleanup;
  okOnePass = pWInfo->okOnePass;

  /* Remember the rowid of every item to be updated.
  */
  sqlite4VdbeAddOp2(v, OP_Rowid, iCur, regOldRowid);
  if( !okOnePass ){
    sqlite4VdbeAddOp2(v, OP_RowSetAdd, regRowSet, regOldRowid);
  }

  /* End the database scan loop.
  */
  sqlite4WhereEnd(pWInfo);

  /* Initialize the count of updated rows
  */
  if( (db->flags & SQLITE_CountRows) && !pParse->pTriggerTab ){
    regRowCount = ++pParse->nMem;
    sqlite4VdbeAddOp2(v, OP_Integer, 0, regRowCount);
  }

  if( !isView ){
    /* 
    ** Open every index that needs updating.  Note that if any
    ** index could potentially invoke a REPLACE conflict resolution 
    ** action, then we need to open all indices because we might need
    ** to be deleting some records.
    */
    if( !okOnePass ) sqlite4OpenTable(pParse, iCur, iDb, pTab, OP_OpenWrite); 
    if( onError==OE_Replace ){
      openAll = 1;
    }else{
      openAll = 0;
      for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
        if( pIdx->onError==OE_Replace ){
          openAll = 1;
          break;
        }
      }
    }
    for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
      assert( aRegIdx );
      if( openAll || aRegIdx[i]>0 ){
        KeyInfo *pKey = sqlite4IndexKeyinfo(pParse, pIdx);
        sqlite4VdbeAddOp4(v, OP_OpenWrite, iCur+i+1, pIdx->tnum, iDb,
                       (char*)pKey, P4_KEYINFO_HANDOFF);
        assert( pParse->nTab>iCur+i+1 );
      }
    }
  }

  /* Top of the update loop */













  if( okOnePass ){
    int a1 = sqlite4VdbeAddOp1(v, OP_NotNull, regOldRowid);
    addr = sqlite4VdbeAddOp0(v, OP_Goto);
    sqlite4VdbeJumpHere(v, a1);
  }else{
    addr = sqlite4VdbeAddOp3(v, OP_RowSetRead, regRowSet, 0, regOldRowid);
  }

  /* Make cursor iCur point to the record that is being updated. If
  ** this record does not exist for some reason (deleted by a trigger,
  ** for example, then jump to the next iteration of the RowSet loop.  */
  sqlite4VdbeAddOp3(v, OP_NotExists, iCur, addr, regOldRowid);

  /* If the record number will change, set register regNewRowid to
  ** contain the new value. If the record number is not being modified,
  ** then regNewRowid is the same register as regOldRowid, which is
  ** already populated.  */
  assert( chngRowid || pTrigger || hasFK || regOldRowid==regNewRowid );
  if( chngRowid ){
    sqlite4ExprCode(pParse, pRowidExpr, regNewRowid);
    sqlite4VdbeAddOp1(v, OP_MustBeInt, regNewRowid);
  }


  /* If there are triggers on this table, populate an array of registers 
  ** with the required old.* column data.  */
  if( hasFK || pTrigger ){
    u32 oldmask = (hasFK ? sqlite4FkOldmask(pParse, pTab) : 0);
    oldmask |= sqlite4TriggerColmask(pParse, 
        pTrigger, pChanges, 0, TRIGGER_BEFORE|TRIGGER_AFTER, pTab, onError
................................................................................
      if( aXRef[i]<0 || oldmask==0xffffffff || (i<32 && (oldmask & (1<<i))) ){
        sqlite4ExprCodeGetColumnOfTable(v, pTab, iCur, i, regOld+i);
      }else{
        sqlite4VdbeAddOp2(v, OP_Null, 0, regOld+i);
      }
    }
    if( chngRowid==0 ){
      sqlite4VdbeAddOp2(v, OP_Copy, regOldRowid, regNewRowid);
    }
  }

  /* Populate the array of registers beginning at regNew with the new
  ** row data. This array is used to check constaints, create the new
  ** table and index records, and as the values for any new.* references
  ** made by triggers.
................................................................................
  ** be used eliminates some redundant opcodes.
  */
  newmask = sqlite4TriggerColmask(
      pParse, pTrigger, pChanges, 1, TRIGGER_BEFORE, pTab, onError
  );
  sqlite4VdbeAddOp3(v, OP_Null, 0, regNew, regNew+pTab->nCol-1);
  for(i=0; i<pTab->nCol; i++){
    if( i==pTab->iPKey ){
      /*sqlite4VdbeAddOp2(v, OP_Null, 0, regNew+i);*/
    }else{
      j = aXRef[i];
      if( j>=0 ){
        sqlite4ExprCode(pParse, pChanges->a[j].pExpr, regNew+i);
      }else if( 0==(tmask&TRIGGER_BEFORE) || i>31 || (newmask&(1<<i)) ){
        /* This branch loads the value of a column that will not be changed 
        ** into a register. This is done if there are no BEFORE triggers, or
        ** if there are one or more BEFORE triggers that use this value via
        ** a new.* reference in a trigger program.
        */
        testcase( i==31 );
        testcase( i==32 );
        sqlite4VdbeAddOp3(v, OP_Column, iCur, i, regNew+i);
        sqlite4ColumnDefault(v, pTab, i, regNew+i);
      }
    }
  }

  /* Fire any BEFORE UPDATE triggers. This happens before constraints are
  ** verified. One could argue that this is wrong.
  */
  if( tmask&TRIGGER_BEFORE ){
    sqlite4VdbeAddOp2(v, OP_Affinity, regNew, pTab->nCol);
    sqlite4TableAffinityStr(v, pTab);
    sqlite4CodeRowTrigger(pParse, pTrigger, TK_UPDATE, pChanges, 
        TRIGGER_BEFORE, pTab, regOldRowid, onError, addr);

    /* The row-trigger may have deleted the row being updated. In this
    ** case, jump to the next row. No updates or AFTER triggers are 
    ** required. This behaviour - what happens when the row being updated
    ** is deleted or renamed by a BEFORE trigger - is left undefined in the
    ** documentation.
    */
    sqlite4VdbeAddOp3(v, OP_NotExists, iCur, addr, regOldRowid);

    /* If it did not delete it, the row-trigger may still have modified 
    ** some of the columns of the row being updated. Load the values for 
    ** all columns not modified by the update statement into their 
    ** registers in case this has happened.
    */
    for(i=0; i<pTab->nCol; i++){
................................................................................
        sqlite4ColumnDefault(v, pTab, i, regNew+i);
      }
    }
  }

  if( !isView ){
    int j1;                       /* Address of jump instruction */


    /* Do constraint checks. */


    sqlite4GenerateConstraintChecks(pParse, pTab, iCur, regNewRowid,
        aRegIdx, (chngRowid?regOldRowid:0), 1, onError, addr, 0);




    /* Do FK constraint checks. */
    if( hasFK ){
      sqlite4FkCheck(pParse, pTab, regOldRowid, 0);
    }

    /* Delete the index entries associated with the current record.  */
    j1 = sqlite4VdbeAddOp3(v, OP_NotExists, iCur, 0, regOldRowid);
    sqlite4GenerateRowIndexDelete(pParse, pTab, iCur, aRegIdx);
  
    /* If changing the record number, delete the old record.  */
    if( hasFK || chngRowid ){
      sqlite4VdbeAddOp2(v, OP_Delete, iCur, 0);
    }
    sqlite4VdbeJumpHere(v, j1);

    if( hasFK ){
      sqlite4FkCheck(pParse, pTab, 0, regNewRowid);
    }
  
    /* Insert the new index entries and the new record. */
    sqlite4CompleteInsertion(pParse, pTab, iCur, regNewRowid, 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 ){
      sqlite4FkActions(pParse, pTab, pChanges, regOldRowid);
    }
  }

  /* Increment the row counter 
  */
  if( (db->flags & SQLITE_CountRows) && !pParse->pTriggerTab){
    sqlite4VdbeAddOp2(v, OP_AddImm, regRowCount, 1);
  }

  sqlite4CodeRowTrigger(pParse, pTrigger, TK_UPDATE, pChanges, 
      TRIGGER_AFTER, pTab, regOldRowid, onError, addr);

  /* Repeat the above with the next record to be updated, until
  ** all record selected by the WHERE clause have been updated.
  */
  sqlite4VdbeAddOp2(v, OP_Goto, 0, addr);
  sqlite4VdbeJumpHere(v, addr);

  /* Close all tables */
  for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
    assert( aRegIdx );
    if( openAll || aRegIdx[i]>0 ){
      sqlite4VdbeAddOp2(v, OP_Close, iCur+i+1, 0);
    }
  }
  sqlite4VdbeAddOp2(v, OP_Close, iCur, 0);

  /* Update the sqlite_sequence table by storing the content of the
  ** maximum rowid counter values recorded while inserting into
................................................................................
    sqlite4VdbeSetColName(v, 0, COLNAME_NAME, "rows updated", SQLITE_STATIC);
  }

update_cleanup:
  sqlite4AuthContextPop(&sContext);
  sqlite4DbFree(db, aRegIdx);
  sqlite4DbFree(db, aXRef);
  sqlite4SrcListDelete(db, pTabList);
  sqlite4ExprListDelete(db, pChanges);
  sqlite4ExprDelete(db, pWhere);
  return;
}
/* Make sure "isView" and other macros defined above are undefined. Otherwise
** thely may interfere with compilation of other functions in this file
** (or in another file, if this file becomes part of the amalgamation).  */

}

/*
** Process an UPDATE statement.
**
**   UPDATE OR IGNORE table_wxyz SET a=b, c=d WHERE e<5 AND f NOT NULL;
**          \_______/ \________/     \______/       \________________/
*            onError   pSrc          pChanges             pWhere
*/
void sqlite4Update(
  Parse *pParse,         /* The parser context */
  SrcList *pSrc,         /* The table in which we should change things */
  ExprList *pChanges,    /* Things to be changed */
  Expr *pWhere,          /* The WHERE clause.  May be null */
  int onError            /* How to handle constraint errors */
){
  int i, j;              /* Loop counters */
  Table *pTab;           /* The table to be updated */
  int addr = 0;          /* VDBE instruction address of the start of the loop */
................................................................................
  sqlite4 *db;           /* The database structure */
  int *aRegIdx = 0;      /* One register assigned to each index to be updated */
  int *aXRef = 0;        /* aXRef[i] is the index in pChanges->a[] of the
                         ** an expression for the i-th column of the table.
                         ** aXRef[i]==-1 if the i-th column is not changed. */
  int chngRowid;         /* True if the record number is being changed */
  Expr *pRowidExpr = 0;  /* Expression defining the new record number */

  AuthContext sContext;  /* The authorization context */
  NameContext sNC;       /* The name-context to resolve expressions in */
  int iDb;               /* Database containing the table being updated */
  int okOnePass;         /* True for one-pass algorithm without the FIFO */
  int hasFK;             /* True if foreign key processing is required */

#ifndef SQLITE_OMIT_TRIGGER
................................................................................
  int isView;            /* True when updating a view (INSTEAD OF trigger) */
  Trigger *pTrigger;     /* List of triggers on pTab, if required */
  int tmask;             /* Mask of TRIGGER_BEFORE|TRIGGER_AFTER */
#endif
  int newmask;           /* Mask of NEW.* columns accessed by BEFORE triggers */

  /* Register Allocations */
  int regOldKey;                  /* Register containing the original PK */

  int regRowCount = 0;   /* A count of rows changed */

  int regNewRowid;       /* The new rowid */
  int regNew;            /* Content of the NEW.* table in triggers */
  int regOld = 0;        /* Content of OLD.* table in triggers */


  int regKeySet = 0;              /* Register containing KeySet object */
  Index *pPk;                     /* The primary key index of this table */
  int iPk;                        /* Offset of primary key in aRegIdx[] */
  int bChngPk = 0;                /* True if any PK columns are updated */
  int bOpenAll = 0;               /* True if all indexes were opened */

  memset(&sContext, 0, sizeof(sContext));
  db = pParse->db;
  if( pParse->nErr || db->mallocFailed ){
    goto update_cleanup;
  }
  assert( pSrc->nSrc==1 );

  /* Locate the table which we want to update. */

  pTab = sqlite4SrcListLookup(pParse, pSrc);
  if( pTab==0 ) goto update_cleanup;
  iDb = sqlite4SchemaToIndex(pParse->db, pTab->pSchema);
  pPk = sqlite4FindPrimaryKey(pTab, &iPk);

  /* Figure out if we have any triggers and if the table being
  ** updated is a view.
  */
#ifndef SQLITE_OMIT_TRIGGER
  pTrigger = sqlite4TriggersExist(pParse, pTab, TK_UPDATE, pChanges, &tmask);
  isView = pTab->pSelect!=0;
................................................................................
  for(i=0; i<pTab->nCol; i++) aXRef[i] = -1;

  /* Allocate a cursors for the main database table and for all indices.
  ** The index cursors might not be used, but if they are used they
  ** need to occur right after the database cursor.  So go ahead and
  ** allocate enough space, just in case.
  */
  pSrc->a[0].iCursor = iCur = pParse->nTab++;
  for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
    pParse->nTab++;
  }

  /* Initialize the name-context */
  memset(&sNC, 0, sizeof(sNC));
  sNC.pParse = pParse;
  sNC.pSrcList = pSrc;

  /* Resolve the column names in all the expressions of the of the UPDATE 
  ** statement. Also find the column index for each column to be updated in 
  ** the pChanges array.  For each column to be updated, make sure we have
  ** authorization to change that column.  

  **
  ** Also, if any columns that are part of the tables primary key are
  ** to be modified, set the bChngPk variable to true. This is significant
  ** because if the primary key changes, *all* index entries need to be
  ** replaced (not just those that index modified columns).  */
  for(i=0; i<pChanges->nExpr; i++){
    int iPkCol;                      /* To iterate through PK columns */

    /* Resolve any names in the expression for this assignment */
    if( sqlite4ResolveExprNames(&sNC, pChanges->a[i].pExpr) ){
      goto update_cleanup;
    }

    /* Resolve the column name on the left of the assignment */
    for(j=0; j<pTab->nCol; j++){
      if( sqlite4StrICmp(pTab->aCol[j].zName, pChanges->a[i].zName)==0 ) break;



    }




    if( j==pTab->nCol ){




      sqlite4ErrorMsg(pParse, "no such column: %s", pChanges->a[i].zName);
      pParse->checkSchema = 1;
      goto update_cleanup;
    }
    aXRef[j] = i;

    /* Check if this column is part of the primary key. If so, set bChngPk. */
    for(iPkCol=0; iPkCol<pPk->nColumn; iPkCol++){
      if( pPk->aiColumn[iPkCol]==j ) bChngPk = 1;
    }

#ifndef SQLITE_OMIT_AUTHORIZATION
    {
      int rc;
      rc = sqlite4AuthCheck(pParse, SQLITE_UPDATE, pTab->zName,
                           pTab->aCol[j].zName, db->aDb[iDb].zName);
      if( rc==SQLITE_DENY ){
        goto update_cleanup;
................................................................................
      }else if( rc==SQLITE_IGNORE ){
        aXRef[j] = -1;
      }
    }
#endif
  }






























  /* Begin generating code. */
  v = sqlite4GetVdbe(pParse);
  if( v==0 ) goto update_cleanup;
  if( pParse->nested==0 ) sqlite4VdbeCountChanges(v);
  sqlite4BeginWriteOperation(pParse, 1, iDb);

#ifndef SQLITE_OMIT_VIRTUALTABLE
  /* Virtual tables must be handled separately */
  if( IsVirtual(pTab) ){
    updateVirtualTable(pParse, pSrc, pTab, pChanges, pRowidExpr, aXRef,
                       pWhere, onError);
    pWhere = 0;
    pSrc = 0;
    goto update_cleanup;
  }
#endif

  hasFK = sqlite4FkRequired(pParse, pTab, aXRef, chngRowid);

  /* Allocate memory for the array aRegIdx[].  There is one entry in the
  ** array for each index associated with table being updated.  Fill in
  ** the value with a register number for indices that are to be used
  ** and with zero for unused indices.  */
  for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){}
  aRegIdx = sqlite4DbMallocZero(db, sizeof(Index*) * nIdx );
  if( aRegIdx==0 ) goto update_cleanup;

  /* Allocate registers for and populate the aRegIdx array. */
  for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
    if( pIdx==pPk || hasFK || bChngPk ){
      aRegIdx[j] = ++pParse->nMem;
    }else{
      for(i=0; i<pIdx->nColumn; i++){
        if( aXRef[pIdx->aiColumn[i]]>=0 ){
          aRegIdx[j] = ++pParse->nMem;
          break;
        }
      }
    }
  }

  /* Allocate other required registers. */
  regKeySet = ++pParse->nMem;
  regOldKey = ++pParse->nMem;
  if( pTrigger || hasFK ){
    regOld = pParse->nMem + 1;
    pParse->nMem += pTab->nCol;
  }
  if( chngRowid || pTrigger || hasFK ){
    regNewRowid = ++pParse->nMem;
  }
................................................................................
  /* Resolve the column names in all the expressions in the
  ** WHERE clause.
  */
  if( sqlite4ResolveExprNames(&sNC, pWhere) ){
    goto update_cleanup;
  }

  /* This block codes a loop that iterates through all rows of the table
  ** identified by the UPDATE statements WHERE clause. The primary key
  ** of each row visited by the loop is added to the KeySet object stored
  ** in register regKeySet.
  **
  ** There is one exception to the above: If static analysis of the WHERE 
  ** clause indicates that the loop will visit at most one row, then the
  ** KeySet object is bypassed and the primary key of the single row (if
  ** any) left in register regOldKey. This is called the "one-pass"
  ** approach. Set okOnePass to true if it can be used in this case.  */
  sqlite4VdbeAddOp3(v, OP_Null, 0, regKeySet, regOldKey);
  pWInfo = sqlite4WhereBegin(pParse, pSrc, pWhere, 0, 0, WHERE_ONEPASS_DESIRED);
  if( pWInfo==0 ) goto update_cleanup;
  okOnePass = pWInfo->okOnePass;
  sqlite4VdbeAddOp2(v, OP_RowKey, iCur, regOldKey);
  if( !okOnePass ){
    sqlite4VdbeAddOp2(v, OP_KeySetAdd, regKeySet, regOldKey);
  }
  sqlite4WhereEnd(pWInfo);

  /* Initialize the count of updated rows */

  if( (db->flags & SQLITE_CountRows) && !pParse->pTriggerTab ){
    regRowCount = ++pParse->nMem;
    sqlite4VdbeAddOp2(v, OP_Integer, 0, regRowCount);
  }

  /* Open every index that needs updating. If any index could potentially 
  ** invoke a REPLACE conflict resolution action, then we need to open all 
  ** indices because we might need to be deleting some records.  */
  if( !isView ){
    /* Set bOpenAll to true if this UPDATE might strike a REPLACE */
    bOpenAll = (onError==OE_Replace);
    for(i=0, pIdx=pTab->pIndex->pNext; pIdx; pIdx=pIdx->pNext, i++){
      if( aRegIdx[i] && pIdx->onError==OE_Replace ) bOpenAll = 1;
    }

    /* If bOpenAll is true, open all indexes. Otherwise, just open those
    ** indexes for which the corresponding aRegIdx[] entry is non-zero
    ** (those that index columns that will be modified by this UPDATE
    ** statement). Also, if the one-pass approach is being used, do not
    ** open the primary key index here - it is already open.  */
    for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
      if( (bOpenAll || aRegIdx[i]) && (okOnePass==0 || pIdx!=pPk) ){
        sqlite4OpenIndex(pParse, iCur+i, iDb, pIdx, OP_OpenWrite);








      }
    }
  }

  /* The next instruction coded is the top of the update loop (executed once
  ** for each row to be updated). 
  **
  ** If okOnePass is true, then regOldKey either contains the encoded PK of 
  ** the row to update, or it is NULL (indicating that this statement will 
  ** update zero rows). If this is the case, jump to the end of the loop 
  ** without doing anything. Otherwise - if okOnePass is true and regOldKey 
  ** contains something other than NULL - proceed.
  **
  ** Or, if okOnePass is false, then the KeySet object stored in register
  ** regKeySet contains the set of encoded PKs for the rows that will
  ** be updated by this statement. Read the next one into register regOldKey.
  ** Or, if the KeySet is already empty, jump to the end of the loop.
  */
  if( okOnePass ){
    int a1 = sqlite4VdbeAddOp1(v, OP_NotNull, regOldKey);
    addr = sqlite4VdbeAddOp0(v, OP_Goto);
    sqlite4VdbeJumpHere(v, a1);
  }else{
    addr = sqlite4VdbeAddOp3(v, OP_KeySetRead, regKeySet, 0, regOldKey);
  }

  /* Make cursor iCur point to the record that is being updated. If
  ** this record does not exist for some reason (deleted by a trigger,
  ** for example, then jump to the next iteration of the KeySet loop. 
  ** TODO: If okOnePass is true, does iCur already point to this record? */










  sqlite4VdbeAddOp4(v, OP_NotFound, iCur+iPk, addr, regOldKey, 0, P4_INT32);

  /* If there are triggers on this table, populate an array of registers 
  ** with the required old.* column data.  */
  if( hasFK || pTrigger ){
    u32 oldmask = (hasFK ? sqlite4FkOldmask(pParse, pTab) : 0);
    oldmask |= sqlite4TriggerColmask(pParse, 
        pTrigger, pChanges, 0, TRIGGER_BEFORE|TRIGGER_AFTER, pTab, onError
................................................................................
      if( aXRef[i]<0 || oldmask==0xffffffff || (i<32 && (oldmask & (1<<i))) ){
        sqlite4ExprCodeGetColumnOfTable(v, pTab, iCur, i, regOld+i);
      }else{
        sqlite4VdbeAddOp2(v, OP_Null, 0, regOld+i);
      }
    }
    if( chngRowid==0 ){
      sqlite4VdbeAddOp2(v, OP_Copy, regOldKey, regNewRowid);
    }
  }

  /* Populate the array of registers beginning at regNew with the new
  ** row data. This array is used to check constaints, create the new
  ** table and index records, and as the values for any new.* references
  ** made by triggers.
................................................................................
  ** be used eliminates some redundant opcodes.
  */
  newmask = sqlite4TriggerColmask(
      pParse, pTrigger, pChanges, 1, TRIGGER_BEFORE, pTab, onError
  );
  sqlite4VdbeAddOp3(v, OP_Null, 0, regNew, regNew+pTab->nCol-1);
  for(i=0; i<pTab->nCol; i++){



    j = aXRef[i];
    if( j>=0 ){
      sqlite4ExprCode(pParse, pChanges->a[j].pExpr, regNew+i);
    }else if( 0==(tmask&TRIGGER_BEFORE) || i>31 || (newmask&(1<<i)) ){
      /* This branch loads the value of a column that will not be changed 
       ** into a register. This is done if there are no BEFORE triggers, or
       ** if there are one or more BEFORE triggers that use this value via
       ** a new.* reference in a trigger program.
       */
      testcase( i==31 );
      testcase( i==32 );
      sqlite4VdbeAddOp3(v, OP_Column, iCur+iPk, i, regNew+i);
      sqlite4ColumnDefault(v, pTab, i, regNew+i);

    }
  }

  /* Fire any BEFORE UPDATE triggers. This happens before constraints are
  ** verified. One could argue that this is wrong.
  */
  if( tmask&TRIGGER_BEFORE ){
    sqlite4VdbeAddOp2(v, OP_Affinity, regNew, pTab->nCol);
    sqlite4TableAffinityStr(v, pTab);
    sqlite4CodeRowTrigger(pParse, pTrigger, TK_UPDATE, pChanges, 
        TRIGGER_BEFORE, pTab, regOldKey, onError, addr);

    /* The row-trigger may have deleted the row being updated. In this
    ** case, jump to the next row. No updates or AFTER triggers are 
    ** required. This behaviour - what happens when the row being updated
    ** is deleted or renamed by a BEFORE trigger - is left undefined in the
    ** documentation.
    */
    sqlite4VdbeAddOp3(v, OP_NotExists, iCur, addr, regOldKey);

    /* If it did not delete it, the row-trigger may still have modified 
    ** some of the columns of the row being updated. Load the values for 
    ** all columns not modified by the update statement into their 
    ** registers in case this has happened.
    */
    for(i=0; i<pTab->nCol; i++){
................................................................................
        sqlite4ColumnDefault(v, pTab, i, regNew+i);
      }
    }
  }

  if( !isView ){
    int j1;                       /* Address of jump instruction */


    /* Do constraint checks. */
    assert( bChngPk==0 || pPk->aiColumn[0]>=0 );
    if( bChngPk==0 ) aRegIdx[iPk] = 0;
    sqlite4GenerateConstraintChecks(

        pParse, pTab, iCur, regNew, aRegIdx, 0, 1, onError, addr, 0
    );
    if( bChngPk==0 ) aRegIdx[iPk] = regOldKey;

    /* Do FK constraint checks. */
    if( hasFK ){
      sqlite4FkCheck(pParse, pTab, regOldKey, 0);
    }

    /* Delete the index entries associated with the current record.  */
    j1 = sqlite4VdbeAddOp4(v, OP_NotFound, iCur+iPk, 0, regOldKey, 0, P4_INT32);
    sqlite4GenerateRowIndexDelete(pParse, pTab, iCur, aRegIdx);
  
    /* Delete the old record */
    if( hasFK || chngRowid ){
      sqlite4VdbeAddOp2(v, OP_Delete, iCur, 0);
    }
    sqlite4VdbeJumpHere(v, j1);

    if( hasFK ){
      sqlite4FkCheck(pParse, pTab, 0, regNewRowid);
    }
  
    /* Insert the new index entries and the new record. */
    sqlite4CompleteInsertion(pParse, pTab, iCur, regNew, 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 ){
      sqlite4FkActions(pParse, pTab, pChanges, regOldKey);
    }
  }

  /* Increment the row counter 
  */
  if( (db->flags & SQLITE_CountRows) && !pParse->pTriggerTab){
    sqlite4VdbeAddOp2(v, OP_AddImm, regRowCount, 1);
  }

  sqlite4CodeRowTrigger(pParse, pTrigger, TK_UPDATE, pChanges, 
      TRIGGER_AFTER, pTab, regOldKey, onError, addr);

  /* Repeat the above with the next record to be updated, until
  ** all record selected by the WHERE clause have been updated.
  */
  sqlite4VdbeAddOp2(v, OP_Goto, 0, addr);
  sqlite4VdbeJumpHere(v, addr);

  /* Close all tables */
  for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
    assert( aRegIdx );
    if( bOpenAll || aRegIdx[i] ){
      sqlite4VdbeAddOp2(v, OP_Close, iCur+i+1, 0);
    }
  }
  sqlite4VdbeAddOp2(v, OP_Close, iCur, 0);

  /* Update the sqlite_sequence table by storing the content of the
  ** maximum rowid counter values recorded while inserting into
................................................................................
    sqlite4VdbeSetColName(v, 0, COLNAME_NAME, "rows updated", SQLITE_STATIC);
  }

update_cleanup:
  sqlite4AuthContextPop(&sContext);
  sqlite4DbFree(db, aRegIdx);
  sqlite4DbFree(db, aXRef);
  sqlite4SrcListDelete(db, pSrc);
  sqlite4ExprListDelete(db, pChanges);
  sqlite4ExprDelete(db, pWhere);
  return;
}
/* Make sure "isView" and other macros defined above are undefined. Otherwise
** thely may interfere with compilation of other functions in this file
** (or in another file, if this file becomes part of the amalgamation).  */

    aData = (const KVByteArray*)pReg->z;
    nData = pReg->n;
  }else{
    aData = 0;
    MemSetTypeFlag(pDest, MEM_Null);
  }
  if( rc==SQLITE_OK && aData ){


    rc = sqlite4VdbeCreateDecoder(db, aData, nData, pC->nField, &pCodec);
    if( rc==0 ){
      pDefault = (pOp->p4type==P4_MEM) ? pOp->p4.pMem : 0;
      rc = sqlite4VdbeDecodeValue(pCodec, pOp->p2, pDefault, pDest);

      sqlite4VdbeDestroyDecoder(pCodec);
    }
  }else{
    sqlite4VdbeMemSetNull(pDest);
  }
  UPDATE_MAX_BLOBSIZE(pDest);
  REGISTER_TRACE(pOp->p3, pDest);
................................................................................
    assert( pIn1 <= &p->aMem[p->nMem] );
    assert( memIsValid(pIn1) );
    applyAffinity(pIn1, cAff, encoding);
    pIn1++;
  }
  break;
}






















































/* Opcode: MakeKey P1 P2 * * *
**
** This must be followed immediately by a MakeRecord opcode.  This
** opcode performs the subsequent MakeRecord and also generates
** a key for the cursor P1 and stores that key in register P2.
*/
/* Opcode: MakeRecord P1 P2 P3 P4 *
**
** Convert registers P1..P1+P2-1 into a data record and store the result
** in register P3.  The OP_Column opcode can be used to decode the record.
**
** P4 may be a string that is P2 characters long.  The nth character of the
** string indicates the column affinity that should be used for the nth
** field of the index key.


**
** The mapping from character to affinity is given by the SQLITE_AFF_
** macros defined in sqliteInt.h.




**
** If P4 is NULL then all index fields have the affinity NONE.

*/
case OP_MakeKey:
case OP_MakeRecord: {
  Mem *pData0;           /* First field to be combined into the record */
  Mem *pLast;            /* Last field of the record */
  Mem *pMem;             /* For looping over inputs */
  int nField;            /* Number of fields in the record */
................................................................................
  nField = pOp->p1;
  zAffinity = pOp->p4.z;
  assert( nField>0 && pOp->p2>0 && pOp->p2+nField<=p->nMem+1 );
  pData0 = &aMem[nField];
  nField = pOp->p2;
  pLast = &pData0[nField-1];

  /* Identify the output register */
  assert( pOp->p3<pOp->p1 || pOp->p3>=pOp->p1+pOp->p2 );
  pOut = &aMem[pOp->p3];
  memAboutToChange(p, pOut);

  /* Loop through the input elements.  Apply affinity to each one and
  ** expand all zero-blobs.
  */
  for(pMem=pData0; pMem<=pLast; pMem++){
    assert( memIsValid(pMem) );
    if( zAffinity ){
      applyAffinity(pMem, *(zAffinity++), encoding);
................................................................................
    }else{
      rc = sqlite4VdbeMemSetStr(pKeyOut, aRec, nRec, 0, SQLITE_DYNAMIC);
      REGISTER_TRACE(keyReg, pKeyOut);
      UPDATE_MAX_BLOBSIZE(pKeyOut);
    }
  }

  /* Compute the value */
  if( rc==SQLITE_OK ){



    aRec = 0;
    rc = sqlite4VdbeEncodeData(db, pData0, nField, &aRec, &nRec);
    if( rc ){
      sqlite4DbFree(db, aRec);
    }else{
      rc = sqlite4VdbeMemSetStr(pOut, aRec, nRec, 0, SQLITE_DYNAMIC);
      REGISTER_TRACE(pOp->p3, pOut);
................................................................................
  VdbeCursor *pCx;

  assert( pOp->p1>=0 );
  pCx = allocateCursor(p, pOp->p1, pOp->p2, -1, 1);
  if( pCx==0 ) goto no_mem;
  pCx->nullRow = 1;
  rc = sqlite4KVStoreOpen(db, "ephm", ":memory:", &pCx->pTmpKV,
          SQLITE_KVOPEN_TEMPORARY | SQLITE_KVOPEN_NO_TRANSACTIONS);







  pCx->pKeyInfo = pOp->p4.pKeyInfo;
  if( pCx->pKeyInfo ) pCx->pKeyInfo->enc = ENC(p->db);

  pCx->isIndex = !pCx->isTable;
  break;
}

/* Opcode: OpenSorter P1 P2 * P4 *
**
** This opcode works like OP_OpenEphemeral except that it opens
................................................................................
  oc = pOp->opcode;
  pC->nullRow = 0;
  if( pC->isTable ){
    nField = 1;
  }else{
    nField = pOp->p4.i;
  }

  rc = sqlite4VdbeEncodeKey(db, pIn3, nField, pC->iRoot, pC->pKeyInfo,
                            &aProbe, &nProbe, 0);
  if( rc ){
    sqlite4DbFree(db, aProbe);
    break;
  }
  rc = sqlite4KVCursorSeek(pC->pKVCur, aProbe, nProbe, 
................................................................................
    rc = sqlite4KVCursorSeek(pC->pKVCur, pProbe, nProbe, +1);
    if( rc==SQLITE_INEXACT || rc==SQLITE_OK ){
      rc = sqlite4KVCursorKey(pC->pKVCur, &pKey, &nKey);
      if( rc==SQLITE_OK && nKey>=nProbe && memcmp(pKey, pProbe, nKey)==0 ){
        alreadyExists = 1;
        pC->nullRow = 0;
      }


    }
  }
  sqlite4DbFree(db, pFree);
  if( pOp->opcode==OP_Found ){
    if( alreadyExists ) pc = pOp->p2 - 1;
  }else{
    if( !alreadyExists ) pc = pOp->p2 - 1;
  }
  break;
}

/* Opcode: IsUnique P1 P2 P3 P4 *
**
** Cursor P1 is open on an index.
**
** The P3 register contains an integer record number. Call this record 
** number R. Register P4 is the first in a set of N contiguous registers
** that make up an unpacked index key that can be used with cursor P1.
** The value of N can be inferred from the KeyInfo.nField of the cursor.
** N includes the rowid value appended to the end of the index record.
** This rowid value may or may not be the same as R.
**
** If any of the N registers beginning with register P4 contains a NULL
** value, jump immediately to P2.
**
** Otherwise, this instruction checks if cursor P1 contains an entry
** where the first (N-1) fields match but the rowid value at the end
** of the index entry is not R. If there is no such entry (meaning that
** a row about to be inserted with rowid R is unique) then control jumps
** to instruction P2. Otherwise, the rowid of the conflicting index
** entry is copied to register P3 and control falls through to the next
** instruction.
**
** See also: NotFound, NotExists, Found
*/
case OP_IsUnique: {        /* jump, in3 */























#if 0
  u16 ii;
  VdbeCursor *pCx;
  KVCursor *pKVCur;
  u16 nField;
  Mem *aMx;
  KVByteArray *pProbe;
................................................................................
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  assert( p->apCsr[pOp->p1]!=0 );
  pOut->u.i = p->apCsr[pOp->p1]->seqCount++;
  break;
}


/* Opcode: NewRowid P1 P2 P3 * *
**
** Get a new integer record number (a.k.a "rowid") used as the key to a table.
** The record number is not previously used as a key in the database
** table that cursor P1 points to.  The new record number is written
** to register P2.
*/
case OP_NewRowid: {           /* out2-prerelease */
................................................................................
  ** probabilistic algorithm
  **
  ** The second algorithm is to select a rowid at random and see if
  ** it already exists in the table.  If it does not exist, we have
  ** succeeded.  If the random rowid does exist, we select a new one
  ** and try again, up to 100 times.
  */
  assert( pC->isTable );

  rc = sqlite4VdbeSeekEnd(pC, -1);
  if( rc==SQLITE_NOTFOUND ){
    v = 0;
    rc = SQLITE_OK;
  }else if( rc==SQLITE_OK ){
    rc = sqlite4KVCursorKey(pC->pKVCur, &aKey, &nKey);
................................................................................
  KVByteArray aKey[24];

  pData = &aMem[pOp->p2];
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  assert( memIsValid(pData) );
  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );
  assert( pC->isTable );
  REGISTER_TRACE(pOp->p2, pData);

  if( pOp->opcode==OP_Insert ){
    pKey = &aMem[pOp->p3];
    assert( pKey->flags & MEM_Int );
    assert( memIsValid(pKey) );
    REGISTER_TRACE(pOp->p3, pKey);
................................................................................
  pOut = &aMem[pOp->p2];
  memAboutToChange(p, pOut);

  /* Note that RowKey and RowData are really exactly the same instruction */
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  pC = p->apCsr[pOp->p1];
  assert( pC->isSorter==0 );
  assert( pC->isIndex || pOp->opcode==OP_RowData );
  assert( pC!=0 );
  assert( pC->nullRow==0 );
  assert( pC->pseudoTableReg==0 );
  assert( !pC->isSorter );
  assert( pC->pKVCur!=0 );
  pCrsr = pC->pKVCur;

................................................................................
    rc = sqlite4KVCursorKey(pCrsr, &pData, &nData);
  }else{
    rc = sqlite4KVCursorData(pCrsr, 0, -1, &pData, &nData);
  }
  if( rc==SQLITE_OK && nData>db->aLimit[SQLITE_LIMIT_LENGTH] ){
    goto too_big;
  }
  sqlite4VdbeMemSetStr(pOut, (const char*)pData, nData, 0, SQLITE_DYNAMIC);
  pOut->enc = SQLITE_UTF8;  /* In case the blob is ever cast to text */
  UPDATE_MAX_BLOBSIZE(pOut);
  break;
}

/* Opcode: Rowid P1 P2 * * *
**
................................................................................
  if( rc==SQLITE_OK ){
    rc = sqlite4VdbeSorterWrite(db, pC, pIn2);
  }
  break;
}


/* Opcode: IdxInsert P1 P2 P3 * P5
**
** Register P2 holds the data and register P3 holds the key for an
** index record.  Write this record into the index specified by the
** cursor P1.
**
** P5 is a flag that provides a hint to the storage layer that this
** insert is likely to be an append.
**
** This instruction only works for indices.  The equivalent instruction
** for tables is OP_Insert.
*/
case OP_IdxInsert: {        /* in2 */
  VdbeCursor *pC;
  Mem *pKey;
  Mem *pData;

  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  pC = p->apCsr[pOp->p1];
  assert( pC );
  assert( pC->pKVCur );
  assert( pC->pKVCur->pStore );
  pKey = &aMem[pOp->p3];




  assert( pKey->flags & MEM_Blob );
  pData = &aMem[pOp->p2];
  assert( pData->flags & MEM_Blob );

  rc = sqlite4KVStoreReplace(
     pC->pKVCur->pStore,
     pKey->z, pKey->n,
     pData->z, pData->n
  );
  break;
}

/* Opcode: IdxDelete P1 P2 P3 * *
**
** The content of P3 registers starting at register P2 form
** an unpacked index key. This opcode removes that entry from the 
** index opened by cursor P1.
*/
case OP_IdxDelete: {
  assert( 0 );
  break;
}

/* Opcode: IdxRowid P1 P2 * * *
**
** Write into register P2 an integer which is the last entry in the record at
** the end of the index key pointed to by cursor P1.  This integer should be
................................................................................
** See also: Rowid, MakeRecord.
*/
case OP_IdxRowid: {              /* out2-prerelease */
  assert( 0 );
  break;
}

/* Opcode: IdxGE P1 P2 P3 P4 P5
**
** The P4 register values beginning with P3 form an unpacked index 
** key that omits the ROWID.  Compare this key value against the index 
** that P1 is currently pointing to, ignoring the ROWID on the P1 index.
**
** If the P1 index entry is greater than or equal to the key value
** then jump to P2.  Otherwise fall through to the next instruction.
**
** If P5 is non-zero then the key value is increased by an epsilon 
** prior to the comparison.  This make the opcode work like IdxGT except
** that if the key from register P3 is a prefix of the key in the cursor,
** the result is false whereas it would be true with IdxGT.
*/
/* Opcode: IdxLT P1 P2 P3 P4 P5
**
** The P4 register values beginning with P3 form an unpacked index 
** key that omits the ROWID.  Compare this key value against the index 
** that P1 is currently pointing to, ignoring the ROWID on the P1 index.
**
** If the P1 index entry is less than the key value then jump to P2.
** Otherwise fall through to the next instruction.
**
** If P5 is non-zero then the key value is increased by an epsilon prior 
** to the comparison.  This makes the opcode work like IdxLE.
*/
case OP_IdxLT:          /* jump */
case OP_IdxGE: {        /* jump */








  assert( 0 );











  break;
}

/* Opcode: Clear P1 P2 P3
**
** Delete all contents of the database table or index whose table number
** in the database file is given by P1.  
................................................................................
**
** This opcode is used to implement the integrity_check pragma.
*/
case OP_IntegrityCk: {
  break;
}
#endif /* SQLITE_OMIT_INTEGRITY_CHECK */












































/* Opcode: RowSetAdd P1 P2 * * *
**
** Insert the integer value held by register P2 into a boolean index
** held in register P1.
**
** An assertion fails if P2 is not an integer.

    aData = (const KVByteArray*)pReg->z;
    nData = pReg->n;
  }else{
    aData = 0;
    MemSetTypeFlag(pDest, MEM_Null);
  }
  if( rc==SQLITE_OK && aData ){
    int nField = pC->nField;
    if( pC->pKeyInfo ) nField = pC->pKeyInfo->nData;
    rc = sqlite4VdbeCreateDecoder(db, aData, nData, nField, &pCodec);
    if( rc==0 ){
      pDefault = (pOp->p4type==P4_MEM) ? pOp->p4.pMem : 0;
      rc = sqlite4VdbeDecodeValue(pCodec, pOp->p2, pDefault, pDest);
      assert( rc==SQLITE_OK );
      sqlite4VdbeDestroyDecoder(pCodec);
    }
  }else{
    sqlite4VdbeMemSetNull(pDest);
  }
  UPDATE_MAX_BLOBSIZE(pDest);
  REGISTER_TRACE(pOp->p3, pDest);
................................................................................
    assert( pIn1 <= &p->aMem[p->nMem] );
    assert( memIsValid(pIn1) );
    applyAffinity(pIn1, cAff, encoding);
    pIn1++;
  }
  break;
}

/* Opcode: MakeIdxKey P1 P2 P3 P4 *
**
** P1 is an open cursor. P2 is the first register in a contiguous array
** of N registers containing values to encode into a database key. N is
** equal to the number of columns indexed by P1, plus the number of 
** trailing primary key columns (if any).
**
** This instruction encodes the N values into a database key and writes
** the result to register P3.
**
** If P4 is of type P4_INT32, then it is a register number. This instruction
** sets register P4 to an integer value - the number of bytes in the 
** generated index key not including any appended primary key column values.
*/
case OP_MakeIdxKey: {
  VdbeCursor *pC;
  KeyInfo *pKeyInfo;
  Mem *pData0;
  u8 *aRec;                       /* The constructed database key */
  int nRec;                       /* Size of aRec[] in bytes */
  int nShort;                     /* Size of aRec[] without PK values */
  Mem *pShort;                    /* Memory cell to write nShort to */
  
  pC = p->apCsr[pOp->p1];
  pKeyInfo = pC->pKeyInfo;
  pData0 = &aMem[pOp->p2];
  pOut = &aMem[pOp->p3];
  aRec = 0;

  memAboutToChange(p, pOut);

  rc = sqlite4VdbeEncodeKey(
    db, pData0, pKeyInfo->nField, pC->iRoot, pKeyInfo, &aRec, &nRec, &nShort
  );

  if( rc ){
    sqlite4DbFree(db, aRec);
  }else{
    if( pOp->p4type==P4_INT32 ){
      pShort = &aMem[pOp->p4.i];
      memAboutToChange(p, pShort);
      pShort->u.i = nShort;
      MemSetTypeFlag(pShort, MEM_Int);
      REGISTER_TRACE(pOp->p4.i, pShort);
    }
    rc = sqlite4VdbeMemSetStr(pOut, aRec, nRec, 0, SQLITE_DYNAMIC);
    REGISTER_TRACE(pOp->p3, pOut);
    UPDATE_MAX_BLOBSIZE(pOut);
  }

  break;
}

/* Opcode: MakeKey P1 P2 * * *
**
** This must be followed immediately by a MakeRecord opcode.  This
** opcode performs the subsequent MakeRecord and also generates
** a key for the cursor P1 and stores that key in register P2.
*/
/* Opcode: MakeRecord P1 P2 P3 P4 *
**
** This opcode uses the array of P2 registers starting at P1 as inputs.

**
** P4 may be a string that is P2 characters long, or it may be NULL. The nth 
** character of the string indicates the column affinity that should be used
** for the nth field of the index key. The mapping from character to affinity
** is given by the SQLITE_AFF_ macros defined in sqliteInt.h. If P4 is NULL
** then all index fields have the affinity NONE.
**

** This opcode expands any zero-blobs within the input array. Then if
** P4 is not NULL it applies the affinities that it specifies to the input
** array elements. Finally, if P3 is not 0, it encodes the input array
** into a data record and stores the result in register P3. The OP_Column 
** opcode can be used to decode the record.
**

** Specifying P3==0 is only useful if the previous opcode is an OP_MakeKey.
*/
case OP_MakeKey:
case OP_MakeRecord: {
  Mem *pData0;           /* First field to be combined into the record */
  Mem *pLast;            /* Last field of the record */
  Mem *pMem;             /* For looping over inputs */
  int nField;            /* Number of fields in the record */
................................................................................
  nField = pOp->p1;
  zAffinity = pOp->p4.z;
  assert( nField>0 && pOp->p2>0 && pOp->p2+nField<=p->nMem+1 );
  pData0 = &aMem[nField];
  nField = pOp->p2;
  pLast = &pData0[nField-1];






  /* Loop through the input elements.  Apply affinity to each one and
  ** expand all zero-blobs.
  */
  for(pMem=pData0; pMem<=pLast; pMem++){
    assert( memIsValid(pMem) );
    if( zAffinity ){
      applyAffinity(pMem, *(zAffinity++), encoding);
................................................................................
    }else{
      rc = sqlite4VdbeMemSetStr(pKeyOut, aRec, nRec, 0, SQLITE_DYNAMIC);
      REGISTER_TRACE(keyReg, pKeyOut);
      UPDATE_MAX_BLOBSIZE(pKeyOut);
    }
  }

  /* If P3 is not 0, compute the data rescord */
  if( rc==SQLITE_OK && pOp->p3 ){
    assert( pOp->p3<pOp->p1 || pOp->p3>=pOp->p1+pOp->p2 );
    pOut = &aMem[pOp->p3];
    memAboutToChange(p, pOut);
    aRec = 0;
    rc = sqlite4VdbeEncodeData(db, pData0, nField, &aRec, &nRec);
    if( rc ){
      sqlite4DbFree(db, aRec);
    }else{
      rc = sqlite4VdbeMemSetStr(pOut, aRec, nRec, 0, SQLITE_DYNAMIC);
      REGISTER_TRACE(pOp->p3, pOut);
................................................................................
  VdbeCursor *pCx;

  assert( pOp->p1>=0 );
  pCx = allocateCursor(p, pOp->p1, pOp->p2, -1, 1);
  if( pCx==0 ) goto no_mem;
  pCx->nullRow = 1;
  rc = sqlite4KVStoreOpen(db, "ephm", ":memory:", &pCx->pTmpKV,
          SQLITE_KVOPEN_TEMPORARY | SQLITE_KVOPEN_NO_TRANSACTIONS
  );
  if( rc==SQLITE_OK ){
    rc = sqlite4KVStoreOpenCursor(pCx->pTmpKV, &pCx->pKVCur);
  }
  if( rc==SQLITE_OK ){
    rc = sqlite4KVStoreBegin(pCx->pTmpKV, 2);
  }
  pCx->pKeyInfo = pOp->p4.pKeyInfo;
  if( pCx->pKeyInfo ) pCx->pKeyInfo->enc = ENC(p->db);

  pCx->isIndex = !pCx->isTable;
  break;
}

/* Opcode: OpenSorter P1 P2 * P4 *
**
** This opcode works like OP_OpenEphemeral except that it opens
................................................................................
  oc = pOp->opcode;
  pC->nullRow = 0;
  if( pC->isTable ){
    nField = 1;
  }else{
    nField = pOp->p4.i;
  }
  pIn3 = &aMem[pOp->p3];
  rc = sqlite4VdbeEncodeKey(db, pIn3, nField, pC->iRoot, pC->pKeyInfo,
                            &aProbe, &nProbe, 0);
  if( rc ){
    sqlite4DbFree(db, aProbe);
    break;
  }
  rc = sqlite4KVCursorSeek(pC->pKVCur, aProbe, nProbe, 
................................................................................
    rc = sqlite4KVCursorSeek(pC->pKVCur, pProbe, nProbe, +1);
    if( rc==SQLITE_INEXACT || rc==SQLITE_OK ){
      rc = sqlite4KVCursorKey(pC->pKVCur, &pKey, &nKey);
      if( rc==SQLITE_OK && nKey>=nProbe && memcmp(pKey, pProbe, nKey)==0 ){
        alreadyExists = 1;
        pC->nullRow = 0;
      }
    }else if( rc==SQLITE_NOTFOUND ){
      rc = SQLITE_OK;
    }
  }
  sqlite4DbFree(db, pFree);
  if( pOp->opcode==OP_Found ){
    if( alreadyExists ) pc = pOp->p2 - 1;
  }else{
    if( !alreadyExists ) pc = pOp->p2 - 1;
  }
  break;
}

/* Opcode: IsUnique P1 P2 P3 P4 *
**
** Cursor P1 is open on an index that enforces a UNIQUE constraint. 
** Register P3 contains an encoded key suitable to be inserted into the 
** index.
**
** Jump to instruction P2 if the encoded key can be inserted into the 
** index without violating a unique constraint. Otherwise, fall through
** to the next instruction.
*/
case OP_IsUnique: {        /* jump, in3 */
  VdbeCursor *pC;
  Mem *pShort;
  Mem *pProbe;
  int nShort;
  int dir;

  KVByteArray *aKey;              /* Key read from cursor */
  KVSize nKey;                    /* Size of aKey in bytes */

  assert( pOp->p4type==P4_INT32 );

  pProbe = &aMem[pOp->p3];
  pShort = &aMem[pOp->p4.i];
  nShort = pShort->u.i;
  pC = p->apCsr[pOp->p1];
  assert( nShort<=pProbe->n );
  assert( (nShort==pProbe->n)==(pC->pKeyInfo->nPK==0) );

  dir = (nShort < pProbe->n);
  rc = sqlite4KVCursorSeek(pC->pKVCur, pProbe->z, nShort, dir);

  if( rc==SQLITE_NOTFOUND ){
    rc = SQLITE_OK;
    pc = pOp->p2-1;
  }else if( rc==SQLITE_INEXACT ){
    assert( nShort<pProbe->n );
    rc = sqlite4KVCursorKey(pC->pKVCur, &aKey, &nKey);
    if( rc==SQLITE_OK ){
      if( nKey<nShort 
       || memcmp(pProbe->z, aKey, nKey)
       || (nKey==pProbe->n && 0==memcmp(pProbe->z, aKey, nKey))
      ){
        pc = pOp->p2-1;
      }
    }
  }

#if 0
  u16 ii;
  VdbeCursor *pCx;
  KVCursor *pKVCur;
  u16 nField;
  Mem *aMx;
  KVByteArray *pProbe;
................................................................................
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  assert( p->apCsr[pOp->p1]!=0 );
  pOut->u.i = p->apCsr[pOp->p1]->seqCount++;
  break;
}


/* Opcode: NewRowid P1 P2 * * *
**
** Get a new integer record number (a.k.a "rowid") used as the key to a table.
** The record number is not previously used as a key in the database
** table that cursor P1 points to.  The new record number is written
** to register P2.
*/
case OP_NewRowid: {           /* out2-prerelease */
................................................................................
  ** probabilistic algorithm
  **
  ** The second algorithm is to select a rowid at random and see if
  ** it already exists in the table.  If it does not exist, we have
  ** succeeded.  If the random rowid does exist, we select a new one
  ** and try again, up to 100 times.
  */


  rc = sqlite4VdbeSeekEnd(pC, -1);
  if( rc==SQLITE_NOTFOUND ){
    v = 0;
    rc = SQLITE_OK;
  }else if( rc==SQLITE_OK ){
    rc = sqlite4KVCursorKey(pC->pKVCur, &aKey, &nKey);
................................................................................
  KVByteArray aKey[24];

  pData = &aMem[pOp->p2];
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  assert( memIsValid(pData) );
  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );

  REGISTER_TRACE(pOp->p2, pData);

  if( pOp->opcode==OP_Insert ){
    pKey = &aMem[pOp->p3];
    assert( pKey->flags & MEM_Int );
    assert( memIsValid(pKey) );
    REGISTER_TRACE(pOp->p3, pKey);
................................................................................
  pOut = &aMem[pOp->p2];
  memAboutToChange(p, pOut);

  /* Note that RowKey and RowData are really exactly the same instruction */
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  pC = p->apCsr[pOp->p1];
  assert( pC->isSorter==0 );

  assert( pC!=0 );
  assert( pC->nullRow==0 );
  assert( pC->pseudoTableReg==0 );
  assert( !pC->isSorter );
  assert( pC->pKVCur!=0 );
  pCrsr = pC->pKVCur;

................................................................................
    rc = sqlite4KVCursorKey(pCrsr, &pData, &nData);
  }else{
    rc = sqlite4KVCursorData(pCrsr, 0, -1, &pData, &nData);
  }
  if( rc==SQLITE_OK && nData>db->aLimit[SQLITE_LIMIT_LENGTH] ){
    goto too_big;
  }
  sqlite4VdbeMemSetStr(pOut, (const char*)pData, nData, 0, SQLITE_TRANSIENT);
  pOut->enc = SQLITE_UTF8;  /* In case the blob is ever cast to text */
  UPDATE_MAX_BLOBSIZE(pOut);
  break;
}

/* Opcode: Rowid P1 P2 * * *
**
................................................................................
  if( rc==SQLITE_OK ){
    rc = sqlite4VdbeSorterWrite(db, pC, pIn2);
  }
  break;
}


/* Opcode: IdxInsert P1 P2 P3 * *
**
** Register P2 holds the data and register P3 holds the key for an
** index record.  Write this record into the index specified by the
** cursor P1.






*/
case OP_IdxInsert: {
  VdbeCursor *pC;
  Mem *pKey;
  Mem *pData;


  pC = p->apCsr[pOp->p1];



  pKey = &aMem[pOp->p3];
  pData = pOp->p2 ? &aMem[pOp->p2] : 0;

  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  assert( pC && pC->pKVCur && pC->pKVCur->pStore );
  assert( pKey->flags & MEM_Blob );

  assert( pData==0 || (pData->flags & MEM_Blob) );

  rc = sqlite4KVStoreReplace(
     pC->pKVCur->pStore,
     pKey->z, pKey->n,
     (pData ? pData->z : 0), (pData ? pData->n : 0)
  );
  break;
}

/* Opcode: IdxDelete P1 * P3 * *
**
** P1 is a cursor open on a database index. P3 contains a key suitable for
** the index. Delete P3 from P1.

*/
case OP_IdxDelete: {

  break;
}

/* Opcode: IdxRowid P1 P2 * * *
**
** Write into register P2 an integer which is the last entry in the record at
** the end of the index key pointed to by cursor P1.  This integer should be
................................................................................
** See also: Rowid, MakeRecord.
*/
case OP_IdxRowid: {              /* out2-prerelease */
  assert( 0 );
  break;
}

/* Opcode: IdxGE P1 P2 P3
**
** P1 is an open cursor. P3 contains a database key formatted by MakeKey.
** This opcode compares the current key that index P1 points to with
** the key in register P3.
**
** If the index key is greater than...






*/












case OP_IdxLT:          /* jump */
case OP_IdxGE: {        /* jump */
  VdbeCursor *pC;
  KVByteArray *aKey;              /* Key from cursor P1 */
  KVSize nKey;                    /* Size of aKey[] in bytes */
  Mem *pCmp;
  int nCmp;
  int res;

  pCmp = &aMem[pOp->p3];
  assert( pCmp->flags & MEM_Blob );
  pC = p->apCsr[pOp->p1];
  rc = sqlite4KVCursorKey(pC->pKVCur, &aKey, &nKey);
  if( rc==SQLITE_OK ){
    nCmp = pCmp->n;
    if( nCmp>nKey ) nCmp = nKey;

    res = memcmp(aKey, pCmp->z, nCmp);
    if( res>0 ){
      pc = pOp->p2 - 1;
    }
  }
  break;
}

/* Opcode: Clear P1 P2 P3
**
** Delete all contents of the database table or index whose table number
** in the database file is given by P1.  
................................................................................
**
** This opcode is used to implement the integrity_check pragma.
*/
case OP_IntegrityCk: {
  break;
}
#endif /* SQLITE_OMIT_INTEGRITY_CHECK */

/* Opcode: KeySetAdd P1 P2 * * *
**
** Read the blob value from register P2 and store it in KeySet object P1.
*/
case OP_KeySetAdd: {         /* in1, in2 */
  pIn1 = &aMem[pOp->p1];
  if( (pIn1->flags & MEM_KeySet)==0 ){
    sqlite4VdbeMemSetKeySet(pIn1);
    if( (pIn1->flags & MEM_KeySet)==0 ) goto no_mem;
  }
  pIn2 = &aMem[pOp->p2];
  assert( pIn2->flags & MEM_Blob );
  sqlite4KeySetInsert(pIn1->u.pKeySet, pIn2->z, pIn2->n);
  break;
}

/* Opcode: KeySetRead P1 P2 P3 * *
**
** Remove a value from MemSet object P1 and store it in register P3.
** Or, if MemSet P1 is already empty, leave P3 unchanged and jump to 
** instruction P2.
*/
case OP_KeySetRead: {       /* in1 */
  const char *aKey;
  int nKey;

  CHECK_FOR_INTERRUPT;
  pIn1 = &aMem[pOp->p1];
  pOut = &aMem[pOp->p3];
  if( (pIn1->flags & MEM_KeySet)
   && (aKey = sqlite4KeySetRead(pIn1->u.pKeySet, &nKey))
  ){
    rc = sqlite4VdbeMemSetStr(pOut, aKey, nKey, 0, SQLITE_TRANSIENT);
    sqlite4KeySetNext(pIn1->u.pKeySet);
  }else{
    /* The KeySet is empty */
    sqlite4VdbeMemSetNull(pIn1);
    pc = pOp->p2 - 1;
  }

  break;
}

/* Opcode: RowSetAdd P1 P2 * * *
**
** Insert the integer value held by register P2 into a boolean index
** held in register P1.
**
** An assertion fails if P2 is not an integer.

  char *z;            /* String or BLOB value */
  double r;           /* Real value */
  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;
  int n;              /* Number of characters in string value, excluding '\0' */
  u16 flags;          /* Some combination of MEM_Null, MEM_Str, MEM_Dyn, etc. */
  u8  type;           /* One of SQLITE_NULL, SQLITE_TEXT, SQLITE_INTEGER, etc */
  u8  enc;            /* SQLITE_UTF8, SQLITE_UTF16BE, SQLITE_UTF16LE */
#ifdef SQLITE_DEBUG
................................................................................
#define MEM_Int       0x0004   /* Value is an integer */
#define MEM_Real      0x0008   /* Value is a real number */
#define MEM_Blob      0x0010   /* Value is a BLOB */
#define MEM_RowSet    0x0020   /* Value is a RowSet object */
#define MEM_Frame     0x0040   /* Value is a VdbeFrame object */
#define MEM_Invalid   0x0080   /* Value is undefined */
#define MEM_TypeMask  0x00ff   /* Mask of type bits */



/* Whenever Mem contains a valid string or blob representation, one of
** the following flags must be set to determine the memory management
** policy for Mem.z.  The MEM_Term flag tells us whether or not the
** string is \000 or \u0000 terminated
*/
#define MEM_Term      0x0200   /* String rep is nul terminated */

  char *z;            /* String or BLOB value */
  double r;           /* Real value */
  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 */
    KeySet *pKeySet;    /* Used only when flags==MEM_KeySet */
    VdbeFrame *pFrame;  /* Used when flags==MEM_Frame */
  } u;
  int n;              /* Number of characters in string value, excluding '\0' */
  u16 flags;          /* Some combination of MEM_Null, MEM_Str, MEM_Dyn, etc. */
  u8  type;           /* One of SQLITE_NULL, SQLITE_TEXT, SQLITE_INTEGER, etc */
  u8  enc;            /* SQLITE_UTF8, SQLITE_UTF16BE, SQLITE_UTF16LE */
#ifdef SQLITE_DEBUG
................................................................................
#define MEM_Int       0x0004   /* Value is an integer */
#define MEM_Real      0x0008   /* Value is a real number */
#define MEM_Blob      0x0010   /* Value is a BLOB */
#define MEM_RowSet    0x0020   /* Value is a RowSet object */
#define MEM_Frame     0x0040   /* Value is a VdbeFrame object */
#define MEM_Invalid   0x0080   /* Value is undefined */
#define MEM_TypeMask  0x00ff   /* Mask of type bits */

#define MEM_KeySet    0x0020   /* Value is a KeySet object */

/* Whenever Mem contains a valid string or blob representation, one of
** the following flags must be set to determine the memory management
** policy for Mem.z.  The MEM_Term flag tells us whether or not the
** string is \000 or \u0000 terminated
*/
#define MEM_Term      0x0200   /* String rep is nul terminated */

      ** callgrind, this causes a certain test case to hit the CPU 4.7 
      ** percent less (x86 linux, gcc version 4.1.2, -O6) than if 
      ** sqlite4MemRelease() were called from here. With -O2, this jumps
      ** to 6.6 percent. The test case is inserting 1000 rows into a table 
      ** with no indexes using a single prepared INSERT statement, bind() 
      ** and reset(). Inserts are grouped into a transaction.
      */
      if( p->flags&(MEM_Agg|MEM_Dyn|MEM_Frame|MEM_RowSet) ){
        sqlite4VdbeMemRelease(p);
      }else if( p->zMalloc ){
        sqlite4DbFree(db, p->zMalloc);
        p->zMalloc = 0;
      }

      p->flags = MEM_Invalid;

      ** callgrind, this causes a certain test case to hit the CPU 4.7 
      ** percent less (x86 linux, gcc version 4.1.2, -O6) than if 
      ** sqlite4MemRelease() were called from here. With -O2, this jumps
      ** to 6.6 percent. The test case is inserting 1000 rows into a table 
      ** with no indexes using a single prepared INSERT statement, bind() 
      ** and reset(). Inserts are grouped into a transaction.
      */
      if( p->flags&(MEM_Agg|MEM_Dyn|MEM_Frame|MEM_KeySet) ){
        sqlite4VdbeMemRelease(p);
      }else if( p->zMalloc ){
        sqlite4DbFree(db, p->zMalloc);
        p->zMalloc = 0;
      }

      p->flags = MEM_Invalid;

    }else if( type<=10 ){
      size = type - 2;
    }else{
      size = type - 9;
    }
    if( i<iVal ){
      ofst += size;


    }else if( type<=2 ){
      sqlite4VdbeMemSetInt64(pOut, type-1);
    }else if( type<=10 ){
      sqlite4_int64 v = ((char*)p->a)[ofst];
      for(i=4; i<type; i++){
        v = v*256 + p->a[ofst+i-3];
      }
................................................................................
** be freed by the caller using sqlite4DbFree() to avoid a memory leak.
*/
int sqlite4VdbeEncodeKey(
  sqlite4 *db,                 /* The database connection */
  Mem *aIn,                    /* Values to be encoded */
  int nIn,                     /* Number of entries in aIn[] */
  int iTabno,                  /* The table this key applies to */
  KeyInfo *pKeyInfo,           /* Collating sequence information */
  u8 **paOut,                  /* Write the resulting key here */
  int *pnOut,                  /* Number of bytes in the key */
  int *pnShort                 /* Number of bytes without the primary key */
){
  int i;
  int rc = SQLITE_OK;
  KeyEncoder x;
................................................................................
    nField = 1;
    iShort = 0;
    xColl = &defaultColl;
    aColl = &xColl;
    so = 0;
  }
  for(i=0; i<nField && rc==SQLITE_OK; i++){
    if( pnShort && i==iShort ) *pnShort = x.nOut;
    rc = encodeOneKeyValue(&x, aIn+i, so ? so[i] : SQLITE_SO_ASC, aColl[i]);

  }
  if( rc ){
    sqlite4DbFree(db, x.aOut);
  }else{
    *paOut = x.aOut;
    *pnOut = x.nOut;
  }

    }else if( type<=10 ){
      size = type - 2;
    }else{
      size = type - 9;
    }
    if( i<iVal ){
      ofst += size;
    }else if( type==0 ){
      /* no-op */
    }else if( type<=2 ){
      sqlite4VdbeMemSetInt64(pOut, type-1);
    }else if( type<=10 ){
      sqlite4_int64 v = ((char*)p->a)[ofst];
      for(i=4; i<type; i++){
        v = v*256 + p->a[ofst+i-3];
      }
................................................................................
** be freed by the caller using sqlite4DbFree() to avoid a memory leak.
*/
int sqlite4VdbeEncodeKey(
  sqlite4 *db,                 /* The database connection */
  Mem *aIn,                    /* Values to be encoded */
  int nIn,                     /* Number of entries in aIn[] */
  int iTabno,                  /* The table this key applies to */
  KeyInfo *pKeyInfo,           /* Collating sequence and sort-order info */
  u8 **paOut,                  /* Write the resulting key here */
  int *pnOut,                  /* Number of bytes in the key */
  int *pnShort                 /* Number of bytes without the primary key */
){
  int i;
  int rc = SQLITE_OK;
  KeyEncoder x;
................................................................................
    nField = 1;
    iShort = 0;
    xColl = &defaultColl;
    aColl = &xColl;
    so = 0;
  }
  for(i=0; i<nField && rc==SQLITE_OK; i++){

    rc = encodeOneKeyValue(&x, aIn+i, so ? so[i] : SQLITE_SO_ASC, aColl[i]);
    if( pnShort && i+1==iShort ) *pnShort = x.nOut;
  }
  if( rc ){
    sqlite4DbFree(db, x.aOut);
  }else{
    *paOut = x.aOut;
    *pnOut = x.nOut;
  }

**
** SQLITE_OK is returned if the conversion is successful (or not required).
** SQLITE_NOMEM may be returned if a malloc() fails during conversion
** between formats.
*/
int sqlite4VdbeChangeEncoding(Mem *pMem, int desiredEnc){
  int rc;
  assert( (pMem->flags&MEM_RowSet)==0 );
  assert( desiredEnc==SQLITE_UTF8 || desiredEnc==SQLITE_UTF16LE
           || desiredEnc==SQLITE_UTF16BE );
  if( !(pMem->flags&MEM_Str) || pMem->enc==desiredEnc ){
    return SQLITE_OK;
  }
  assert( pMem->db==0 || sqlite4_mutex_held(pMem->db->mutex) );
#ifdef SQLITE_OMIT_UTF16
................................................................................
int sqlite4VdbeMemGrow(Mem *pMem, int n, int preserve){
  assert( 1 >=
    ((pMem->zMalloc && pMem->zMalloc==pMem->z) ? 1 : 0) +
    (((pMem->flags&MEM_Dyn)&&pMem->xDel) ? 1 : 0) + 
    ((pMem->flags&MEM_Ephem) ? 1 : 0) + 
    ((pMem->flags&MEM_Static) ? 1 : 0)
  );
  assert( (pMem->flags&MEM_RowSet)==0 );

  if( n<32 ) n = 32;
  if( sqlite4DbMallocSize(pMem->db, pMem->zMalloc)<n ){
    if( preserve && pMem->z==pMem->zMalloc ){
      pMem->z = pMem->zMalloc = sqlite4DbReallocOrFree(pMem->db, pMem->z, n);
      preserve = 0;
    }else{
................................................................................
** overwritten or altered.
**
** Return SQLITE_OK on success or SQLITE_NOMEM if malloc fails.
*/
int sqlite4VdbeMemMakeWriteable(Mem *pMem){
  int f;
  assert( pMem->db==0 || sqlite4_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( sqlite4VdbeMemGrow(pMem, pMem->n + 2, 1) ){
      return SQLITE_NOMEM;
    }
    pMem->z[pMem->n] = 0;
................................................................................
  int fg = pMem->flags;
  const int nByte = 32;

  assert( pMem->db==0 || sqlite4_mutex_held(pMem->db->mutex) );
  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( sqlite4VdbeMemGrow(pMem, nByte, 0) ){
    return SQLITE_NOMEM;
  }

................................................................................
void sqlite4VdbeMemReleaseExternal(Mem *p){
  assert( p->db==0 || sqlite4_mutex_held(p->db->mutex) );
  if( p->flags&MEM_Agg ){
    sqlite4VdbeMemFinalize(p, p->u.pDef);
    assert( (p->flags & MEM_Agg)==0 );
    sqlite4VdbeMemRelease(p);
  }else if( p->flags&MEM_Dyn && p->xDel ){
    assert( (p->flags&MEM_RowSet)==0 );
    assert( p->xDel!=SQLITE_DYNAMIC );
    p->xDel((void *)p->z);
    p->xDel = 0;
  }else if( p->flags&MEM_RowSet ){
    sqlite4RowSetClear(p->u.pRowSet);
  }else if( p->flags&MEM_Frame ){
    sqlite4VdbeMemSetNull(p);
  }
}

/*
** Release any memory held by the Mem. This may leave the Mem in an
................................................................................
*/
void sqlite4VdbeMemSetNull(Mem *pMem){
  if( pMem->flags & MEM_Frame ){
    VdbeFrame *pFrame = pMem->u.pFrame;
    pFrame->pParent = pFrame->v->pDelFrame;
    pFrame->v->pDelFrame = pFrame;
  }
  if( pMem->flags & MEM_RowSet ){
    sqlite4RowSetClear(pMem->u.pRowSet);
  }
  MemSetTypeFlag(pMem, MEM_Null);
  pMem->type = SQLITE_NULL;
}

/*
** Delete any previous value and set the value to be a BLOB of length
................................................................................
    assert( pMem->zMalloc );
    pMem->u.pRowSet = sqlite4RowSetInit(db, pMem->zMalloc, 
                                       sqlite4DbMallocSize(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
** too large - whose size exceeds SQLITE_MAX_LENGTH.
*/
int sqlite4VdbeMemTooBig(Mem *p){
  assert( p->db!=0 );

**
** SQLITE_OK is returned if the conversion is successful (or not required).
** SQLITE_NOMEM may be returned if a malloc() fails during conversion
** between formats.
*/
int sqlite4VdbeChangeEncoding(Mem *pMem, int desiredEnc){
  int rc;
  assert( (pMem->flags&MEM_KeySet)==0 );
  assert( desiredEnc==SQLITE_UTF8 || desiredEnc==SQLITE_UTF16LE
           || desiredEnc==SQLITE_UTF16BE );
  if( !(pMem->flags&MEM_Str) || pMem->enc==desiredEnc ){
    return SQLITE_OK;
  }
  assert( pMem->db==0 || sqlite4_mutex_held(pMem->db->mutex) );
#ifdef SQLITE_OMIT_UTF16
................................................................................
int sqlite4VdbeMemGrow(Mem *pMem, int n, int preserve){
  assert( 1 >=
    ((pMem->zMalloc && pMem->zMalloc==pMem->z) ? 1 : 0) +
    (((pMem->flags&MEM_Dyn)&&pMem->xDel) ? 1 : 0) + 
    ((pMem->flags&MEM_Ephem) ? 1 : 0) + 
    ((pMem->flags&MEM_Static) ? 1 : 0)
  );
  assert( (pMem->flags&MEM_KeySet)==0 );

  if( n<32 ) n = 32;
  if( sqlite4DbMallocSize(pMem->db, pMem->zMalloc)<n ){
    if( preserve && pMem->z==pMem->zMalloc ){
      pMem->z = pMem->zMalloc = sqlite4DbReallocOrFree(pMem->db, pMem->z, n);
      preserve = 0;
    }else{
................................................................................
** overwritten or altered.
**
** Return SQLITE_OK on success or SQLITE_NOMEM if malloc fails.
*/
int sqlite4VdbeMemMakeWriteable(Mem *pMem){
  int f;
  assert( pMem->db==0 || sqlite4_mutex_held(pMem->db->mutex) );
  assert( (pMem->flags&MEM_KeySet)==0 );
  ExpandBlob(pMem);
  f = pMem->flags;
  if( (f&(MEM_Str|MEM_Blob)) && pMem->z!=pMem->zMalloc ){
    if( sqlite4VdbeMemGrow(pMem, pMem->n + 2, 1) ){
      return SQLITE_NOMEM;
    }
    pMem->z[pMem->n] = 0;
................................................................................
  int fg = pMem->flags;
  const int nByte = 32;

  assert( pMem->db==0 || sqlite4_mutex_held(pMem->db->mutex) );
  assert( !(fg&MEM_Zero) );
  assert( !(fg&(MEM_Str|MEM_Blob)) );
  assert( fg&(MEM_Int|MEM_Real) );
  assert( (pMem->flags&MEM_KeySet)==0 );
  assert( EIGHT_BYTE_ALIGNMENT(pMem) );


  if( sqlite4VdbeMemGrow(pMem, nByte, 0) ){
    return SQLITE_NOMEM;
  }

................................................................................
void sqlite4VdbeMemReleaseExternal(Mem *p){
  assert( p->db==0 || sqlite4_mutex_held(p->db->mutex) );
  if( p->flags&MEM_Agg ){
    sqlite4VdbeMemFinalize(p, p->u.pDef);
    assert( (p->flags & MEM_Agg)==0 );
    sqlite4VdbeMemRelease(p);
  }else if( p->flags&MEM_Dyn && p->xDel ){
    assert( (p->flags&MEM_KeySet)==0 );
    assert( p->xDel!=SQLITE_DYNAMIC );
    p->xDel((void *)p->z);
    p->xDel = 0;
  }else if( p->flags&MEM_KeySet ){
    sqlite4KeySetFree(p->u.pKeySet);
  }else if( p->flags&MEM_Frame ){
    sqlite4VdbeMemSetNull(p);
  }
}

/*
** Release any memory held by the Mem. This may leave the Mem in an
................................................................................
*/
void sqlite4VdbeMemSetNull(Mem *pMem){
  if( pMem->flags & MEM_Frame ){
    VdbeFrame *pFrame = pMem->u.pFrame;
    pFrame->pParent = pFrame->v->pDelFrame;
    pFrame->v->pDelFrame = pFrame;
  }
  if( pMem->flags & MEM_KeySet ){
    sqlite4KeySetFree(pMem->u.pKeySet);
  }
  MemSetTypeFlag(pMem, MEM_Null);
  pMem->type = SQLITE_NULL;
}

/*
** Delete any previous value and set the value to be a BLOB of length
................................................................................
    assert( pMem->zMalloc );
    pMem->u.pRowSet = sqlite4RowSetInit(db, pMem->zMalloc, 
                                       sqlite4DbMallocSize(db, pMem->zMalloc));
    assert( pMem->u.pRowSet!=0 );
    pMem->flags = MEM_RowSet;
  }
}

void sqlite4VdbeMemSetKeySet(Mem *pMem){
  sqlite4 *db = pMem->db;
  assert( db!=0 );
  assert( (pMem->flags & MEM_KeySet)==0 );
  sqlite4VdbeMemRelease(pMem);

  pMem->u.pKeySet = sqlite4KeySetInit(db);
  pMem->flags = MEM_KeySet;
}

/*
** Return true if the Mem object contains a TEXT or BLOB that is
** too large - whose size exceeds SQLITE_MAX_LENGTH.
*/
int sqlite4VdbeMemTooBig(Mem *p){
  assert( p->db!=0 );

  Bitmask notValid,           /* Cursors not available for any purpose */
  ExprList *pOrderBy,         /* The ORDER BY clause */
  ExprList *pDistinct,        /* The select-list if query is DISTINCT */
  WhereCost *pCost            /* Lowest cost query plan */
){
  int iCur = pSrc->iCursor;   /* The cursor of the table to be accessed */
  Index *pProbe;              /* An index we are evaluating */
  Index *pIdx;                /* Copy of pProbe, or zero for IPK index */
  int eqTermMask;             /* Current mask of valid equality operators */
  int idxEqTermMask;          /* Index mask of valid equality operators */
  Index sPk;                  /* A fake index object for the primary key */
  tRowcnt aiRowEstPk[2];      /* The aiRowEst[] value for the sPk index */
  int aiColumnPk = -1;        /* The aColumn[] value for the sPk index */
  int wsFlagMask;             /* Allowed flags in pCost->plan.wsFlag */

  /* Initialize the cost to a worst-case value */
  memset(pCost, 0, sizeof(*pCost));
  pCost->rCost = SQLITE_BIG_DBL;

  /* If the pSrc table is the right table of a LEFT JOIN then we may not
................................................................................
  */
  if( pSrc->jointype & JT_LEFT ){
    idxEqTermMask = WO_EQ|WO_IN;
  }else{
    idxEqTermMask = WO_EQ|WO_IN|WO_ISNULL;
  }









  if( pSrc->pIndex ){
    /* An INDEXED BY clause specifies a particular index to use */

    pIdx = pProbe = pSrc->pIndex;
    wsFlagMask = ~(WHERE_ROWID_EQ|WHERE_ROWID_RANGE);
    eqTermMask = idxEqTermMask;
  }else{
    /* There is no INDEXED BY clause.  Create a fake Index object in local
    ** variable sPk to represent the rowid primary key index.  Make this
    ** fake index the first in a chain of Index objects with all of the real
    ** indices to follow */
    Index *pFirst;                  /* First of real indices on the table */
    memset(&sPk, 0, sizeof(Index));
    sPk.nColumn = 1;
    sPk.aiColumn = &aiColumnPk;
    sPk.aiRowEst = aiRowEstPk;
    sPk.onError = OE_Replace;
    sPk.pTable = pSrc->pTab;
    aiRowEstPk[0] = pSrc->pTab->nRowEst;
    aiRowEstPk[1] = 1;
    pFirst = pSrc->pTab->pIndex;
    if( pSrc->notIndexed==0 ){
      /* The real indices of the table are only considered if the
      ** NOT INDEXED qualifier is omitted from the FROM clause */
      sPk.pNext = pFirst;
    }
    pProbe = &sPk;
    wsFlagMask = ~(
        WHERE_COLUMN_IN|WHERE_COLUMN_EQ|WHERE_COLUMN_NULL|WHERE_COLUMN_RANGE
    );
    eqTermMask = WO_EQ|WO_IN;
    pIdx = 0;
  }






  /* Loop over all indices looking for the best one to use
  */
  for(; pProbe; pIdx=pProbe=pProbe->pNext){

    const tRowcnt * const aiRowEst = pProbe->aiRowEst;
    double cost;                /* Cost of using pProbe */
    double nRow;                /* Estimated number of rows in result set */
    double log10N = (double)1;  /* base-10 logarithm of nRow (inexact) */
    int rev;                    /* True to scan in reverse order */
    int wsFlags = 0;
    Bitmask used = 0;
................................................................................
#ifdef SQLITE_ENABLE_STAT3
    WhereTerm *pFirstTerm = 0;    /* First term matching the index */
#endif

    /* Determine the values of nEq and nInMul */
    for(nEq=0; nEq<pProbe->nColumn; nEq++){
      int j = pProbe->aiColumn[nEq];
      pTerm = findTerm(pWC, iCur, j, notReady, eqTermMask, pIdx);
      if( pTerm==0 ) break;
      wsFlags |= (WHERE_COLUMN_EQ|WHERE_ROWID_EQ);
      testcase( pTerm->pWC!=pWC );
      if( pTerm->eOperator & WO_IN ){
        Expr *pExpr = pTerm->pExpr;
        wsFlags |= WHERE_COLUMN_IN;
        if( ExprHasProperty(pExpr, EP_xIsSelect) ){
................................................................................
      testcase( wsFlags & WHERE_COLUMN_IN );
      testcase( wsFlags & WHERE_COLUMN_NULL );
      if( (wsFlags & (WHERE_COLUMN_IN|WHERE_COLUMN_NULL))==0 ){
        wsFlags |= WHERE_UNIQUE;
      }
    }else if( pProbe->bUnordered==0 ){
      int j = (nEq==pProbe->nColumn ? -1 : pProbe->aiColumn[nEq]);
      if( findTerm(pWC, iCur, j, notReady, WO_LT|WO_LE|WO_GT|WO_GE, pIdx) ){
        WhereTerm *pTop = findTerm(pWC, iCur, j, notReady, WO_LT|WO_LE, pIdx);
        WhereTerm *pBtm = findTerm(pWC, iCur, j, notReady, WO_GT|WO_GE, pIdx);
        whereRangeScanEst(pParse, pProbe, nEq, pBtm, pTop, &rangeDiv);
        if( pTop ){
          nBound = 1;
          wsFlags |= WHERE_TOP_LIMIT;
          used |= pTop->prereqRight;
          testcase( pTop->pWC!=pWC );
        }
................................................................................
    ** order of the DISTINCT expressions, clear bDist and set the appropriate
    ** flags in wsFlags. */
    if( isDistinctIndex(pParse, pWC, pProbe, iCur, pDistinct, nEq) ){
      bDist = 0;
      wsFlags |= WHERE_ROWID_RANGE|WHERE_COLUMN_RANGE|WHERE_DISTINCT;
    }

    /* If currently calculating the cost of using an index (not the IPK
    ** index), determine if all required column data may be obtained without 
    ** using the main table (i.e. if the index is a covering
    ** index for this query). If it is, set the WHERE_IDX_ONLY flag in
    ** wsFlags. Otherwise, set the bLookup variable to true.  */





    if( pIdx && wsFlags ){
      Bitmask m = pSrc->colUsed;
      int j;
      for(j=0; j<pIdx->nColumn; j++){
        int x = pIdx->aiColumn[j];
        if( x<BMS-1 ){
          m &= ~(((Bitmask)1)<<x);
        }
      }
      if( m==0 ){
        wsFlags |= WHERE_IDX_ONLY;
      }else{
        bLookup = 1;
      }
    }



    /*
    ** Estimate the number of rows of output.  For an "x IN (SELECT...)"
    ** constraint, do not let the estimate exceed half the rows in the table.
    */
    nRow = (double)(aiRowEst[nEq] * nInMul);
    if( bInEst && nRow*2>aiRowEst[0] ){
................................................................................
      ** decision and one which we expect to revisit in the future.  But
      ** it seems to be working well enough at the moment.
      */
      cost = aiRowEst[0]*4;
    }else{
      log10N = estLog(aiRowEst[0]);
      cost = nRow;
      if( pIdx ){
        if( bLookup ){
          /* For an index lookup followed by a table lookup:
          **    nInMul index searches to find the start of each index range
          **  + nRow steps through the index
          **  + nRow table searches to lookup the table entry using the rowid
          */
          cost += (nInMul + nRow)*log10N;
        }else{
          /* For a covering index:
          **     nInMul index searches to find the initial entry 
          **   + nRow steps through the index
          */
          cost += nInMul*log10N;
        }
      }else{
        /* For a rowid primary key lookup:
        **    nInMult table searches to find the initial entry for each range
        **  + nRow steps through the table
        */
        cost += nInMul*log10N;
      }
    }

    /* Add in the estimated cost of sorting the result.  Actual experimental
    ** measurements of sorting performance in SQLite show that sorting time
................................................................................
      if( nRow<2 ) nRow = 2;
    }


    WHERETRACE((
      "%s(%s): nEq=%d nInMul=%d rangeDiv=%d bSort=%d bLookup=%d wsFlags=0x%x\n"
      "         notReady=0x%llx log10N=%.1f nRow=%.1f cost=%.1f used=0x%llx\n",
      pSrc->pTab->zName, (pIdx ? pIdx->zName : "ipk"), 
      nEq, nInMul, (int)rangeDiv, bSort, bLookup, wsFlags,
      notReady, log10N, nRow, cost, used
    ));

    /* If this index is the best we have seen so far, then record this
    ** index and its cost in the pCost structure.
    */
    if( (!pIdx || wsFlags)
     && (cost<pCost->rCost || (cost<=pCost->rCost && nRow<pCost->plan.nRow))
    ){
      pCost->rCost = cost;
      pCost->used = used;
      pCost->plan.nRow = nRow;
      pCost->plan.wsFlags = (wsFlags&wsFlagMask);
      pCost->plan.nEq = nEq;
      pCost->plan.u.pIdx = pIdx;
    }

    /* If there was an INDEXED BY clause, then only that one index is
    ** considered. */
    if( pSrc->pIndex ) break;

    /* Reset masks for the next index in the loop */
    wsFlagMask = ~(WHERE_ROWID_EQ|WHERE_ROWID_RANGE);
    eqTermMask = idxEqTermMask;
  }

  /* If there is no ORDER BY clause and the SQLITE_ReverseOrder flag
................................................................................
    int nConstraint;             /* Number of constraint terms */
    Index *pIdx;                 /* The index we will be using */
    int iIdxCur;                 /* The VDBE cursor for the index */
    int nExtraReg = 0;           /* Number of extra registers needed */
    int op;                      /* Instruction opcode */
    char *zStartAff;             /* Affinity for start of range constraint */
    char *zEndAff;               /* Affinity for end of range constraint */


    pIdx = pLevel->plan.u.pIdx;
    iIdxCur = pLevel->iIdxCur;
    k = (nEq==pIdx->nColumn ? -1 : pIdx->aiColumn[nEq]);

    /* If this loop satisfies a sort order (pOrderBy) request that 
    ** was passed to this function to implement a "SELECT min(x) ..." 
................................................................................
    testcase( op==OP_Last );
    testcase( op==OP_SeekGt );
    testcase( op==OP_SeekGe );
    testcase( op==OP_SeekLe );
    testcase( op==OP_SeekLt );
    sqlite4VdbeAddOp4Int(v, op, iIdxCur, addrNxt, regBase, nConstraint);

    /* Load the value for the inequality constraint at the end of the
    ** range (if any).
    */








    nConstraint = nEq;
    if( pRangeEnd ){
      Expr *pRight = pRangeEnd->pExpr->pRight;
      sqlite4ExprCacheRemove(pParse, regBase+nEq, 1);
      sqlite4ExprCode(pParse, pRight, regBase+nEq);
      if( (pRangeEnd->wtFlags & TERM_VNULL)==0 ){
        sqlite4ExprCodeIsNullJump(v, pRight, regBase+nEq, addrNxt);
      }
      if( zEndAff ){
        if( sqlite4CompareAffinity(pRight, zEndAff[nEq])==SQLITE_AFF_NONE){
          /* Since the comparison is to be performed with no conversions
          ** applied to the operands, set the affinity to apply to pRight to 
          ** SQLITE_AFF_NONE.  */
          zEndAff[nEq] = SQLITE_AFF_NONE;
        }
        if( sqlite4ExprNeedsNoAffinityChange(pRight, zEndAff[nEq]) ){
          zEndAff[nEq] = SQLITE_AFF_NONE;
        }
      }  
      codeApplyAffinity(pParse, regBase, nEq+1, zEndAff);
      nConstraint++;
      testcase( pRangeEnd->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
    }







    sqlite4DbFree(pParse->db, zStartAff);
    sqlite4DbFree(pParse->db, zEndAff);

    /* Top of the loop body */
    pLevel->p2 = sqlite4VdbeCurrentAddr(v);

    /* Check if the index cursor is past the end of the range. */
    op = aEndOp[(pRangeEnd || nEq) * (1 + bRev)];
    testcase( op==OP_Noop );
    testcase( op==OP_IdxGE );
    testcase( op==OP_IdxLT );
    if( op!=OP_Noop ){

      sqlite4VdbeAddOp4Int(v, op, iIdxCur, addrNxt, regBase, nConstraint);
      sqlite4VdbeChangeP5(v, endEq!=bRev ?1:0);
    }

    /* If there are inequality constraints, check that the value
    ** of the table column that the inequality contrains is not NULL.
    ** If it is, jump to the next iteration of the loop.
    */
................................................................................
      sqlite4VdbeAddOp2(v, OP_IsNull, r1, addrCont);
    }
    sqlite4ReleaseTempReg(pParse, r1);

    /* Seek the table cursor, if required */
    disableTerm(pLevel, pRangeStart);
    disableTerm(pLevel, pRangeEnd);
    if( !omitTable ){

      iRowidReg = iReleaseReg = sqlite4GetTempReg(pParse);
      sqlite4VdbeAddOp2(v, OP_IdxRowid, iIdxCur, iRowidReg);
      sqlite4ExprCacheStore(pParse, iCur, -1, iRowidReg);
      sqlite4VdbeAddOp2(v, OP_Seek, iCur, iRowidReg);  /* Deferred seek */
    }

    /* Record the instruction used to terminate the loop. Disable 
................................................................................
      pLevel->op = OP_Noop;
    }else if( bRev ){
      pLevel->op = OP_Prev;
    }else{
      pLevel->op = OP_Next;
    }
    pLevel->p1 = iIdxCur;

  }else

#ifndef SQLITE_OMIT_OR_OPTIMIZATION
  if( pLevel->plan.wsFlags & WHERE_MULTI_OR ){
    /* Case 4:  Two or more separately indexed terms connected by OR
    **
    ** Example:
................................................................................
      int iCur = pTabItem->iCursor;
      sqlite4VdbeAddOp4(v, OP_VOpen, iCur, 0, 0, pVTab, P4_VTAB);
    }else
#endif
    if( (pLevel->plan.wsFlags & WHERE_IDX_ONLY)==0
         && (wctrlFlags & WHERE_OMIT_OPEN_CLOSE)==0 ){
      int op = pWInfo->okOnePass ? OP_OpenWrite : OP_OpenRead;
      sqlite4OpenTable(pParse, pTabItem->iCursor, iDb, pTab, op);
      testcase( pTab->nCol==BMS-1 );
      testcase( pTab->nCol==BMS );

      if( !pWInfo->okOnePass && pTab->nCol<BMS ){
        Bitmask b = pTabItem->colUsed;
        int n = 0;
        for(; b; b=b>>1, n++){}
        sqlite4VdbeChangeP4(v, sqlite4VdbeCurrentAddr(v)-1, 
                            SQLITE_INT_TO_PTR(n), P4_INT32);
        assert( n<=pTab->nCol );
      }

    }else{
      sqlite4TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);
    }
#ifndef SQLITE_OMIT_AUTOMATIC_INDEX
    if( (pLevel->plan.wsFlags & WHERE_TEMP_INDEX)!=0 ){
      constructAutomaticIndex(pParse, pWC, pTabItem, notReady, pLevel);
    }else
#endif
    if( (pLevel->plan.wsFlags & WHERE_INDEXED)!=0 ){
      Index *pIx = pLevel->plan.u.pIdx;



      KeyInfo *pKey = sqlite4IndexKeyinfo(pParse, pIx);
      int iIdxCur = pLevel->iIdxCur;
      assert( pIx->pSchema==pTab->pSchema );
      assert( iIdxCur>=0 );
      sqlite4VdbeAddOp4(v, OP_OpenRead, iIdxCur, pIx->tnum, iDb,
                        (char*)pKey, P4_KEYINFO_HANDOFF);
      VdbeComment((v, "%s", pIx->zName));

    }
    sqlite4CodeVerifySchema(pParse, iDb);
    notReady &= ~getMask(pWC->pMaskSet, pTabItem->iCursor);
  }
  pWInfo->iTop = sqlite4VdbeCurrentAddr(v);
  if( db->mallocFailed ) goto whereBeginError;

................................................................................
     && (pWInfo->wctrlFlags & WHERE_OMIT_OPEN_CLOSE)==0
    ){
      int ws = pLevel->plan.wsFlags;
      if( !pWInfo->okOnePass && (ws & WHERE_IDX_ONLY)==0 ){
        sqlite4VdbeAddOp1(v, OP_Close, pTabItem->iCursor);
      }
      if( (ws & WHERE_INDEXED)!=0 && (ws & WHERE_TEMP_INDEX)==0 ){

        sqlite4VdbeAddOp1(v, OP_Close, pLevel->iIdxCur);

      }
    }

    /* If this scan uses an index, make code substitutions to read data
    ** from the index in preference to the table. Sometimes, this means
    ** the table need never be read from. This is a performance boost,
    ** as the vdbe level waits until the table is read before actually

  Bitmask notValid,           /* Cursors not available for any purpose */
  ExprList *pOrderBy,         /* The ORDER BY clause */
  ExprList *pDistinct,        /* The select-list if query is DISTINCT */
  WhereCost *pCost            /* Lowest cost query plan */
){
  int iCur = pSrc->iCursor;   /* The cursor of the table to be accessed */
  Index *pProbe;              /* An index we are evaluating */
  Index *pFirst;              /* First index to evaluate */
  int eqTermMask;             /* Current mask of valid equality operators */
  int idxEqTermMask;          /* Index mask of valid equality operators */



  int wsFlagMask;             /* Allowed flags in pCost->plan.wsFlag */

  /* Initialize the cost to a worst-case value */
  memset(pCost, 0, sizeof(*pCost));
  pCost->rCost = SQLITE_BIG_DBL;

  /* If the pSrc table is the right table of a LEFT JOIN then we may not
................................................................................
  */
  if( pSrc->jointype & JT_LEFT ){
    idxEqTermMask = WO_EQ|WO_IN;
  }else{
    idxEqTermMask = WO_EQ|WO_IN|WO_ISNULL;
  }

  /* Normally, this function considers all indexes attached to the table
  ** being queried. Except, if an INDEXED BY clause is specified then only
  ** the named index is considered. And if a NOT INDEXED clause was present
  ** only the PRIMARY KEY index may be considered.  
  */
  assert( pSrc->notIndexed==0 && "TODO: Re-enable this" );
  assert( pSrc->pIndex==0 && "TODO: Re-enable this" );
#if 0
  if( pSrc->pIndex ){
    /* An INDEXED BY clause specifies a particular index to use */
    assert(!"TODO: Fix this");
    pFirst = pSrc->pIndex;
    wsFlagMask = ~(WHERE_ROWID_EQ|WHERE_ROWID_RANGE);
    eqTermMask = idxEqTermMask;
  }else{




















    wsFlagMask = ~(
        WHERE_COLUMN_IN|WHERE_COLUMN_EQ|WHERE_COLUMN_NULL|WHERE_COLUMN_RANGE
    );
    eqTermMask = WO_EQ|WO_IN;
    pFirst = pSrc->pTab->pIndex;
  }
#else
  wsFlagMask = ~(WHERE_ROWID_EQ|WHERE_ROWID_RANGE);
  eqTermMask = idxEqTermMask;
  pFirst = pSrc->pTab->pIndex;
#endif

  /* Loop over all indices looking for the best one to use */


  for(pProbe=pFirst; pProbe; pProbe=pProbe->pNext){
    const tRowcnt * const aiRowEst = pProbe->aiRowEst;
    double cost;                /* Cost of using pProbe */
    double nRow;                /* Estimated number of rows in result set */
    double log10N = (double)1;  /* base-10 logarithm of nRow (inexact) */
    int rev;                    /* True to scan in reverse order */
    int wsFlags = 0;
    Bitmask used = 0;
................................................................................
#ifdef SQLITE_ENABLE_STAT3
    WhereTerm *pFirstTerm = 0;    /* First term matching the index */
#endif

    /* Determine the values of nEq and nInMul */
    for(nEq=0; nEq<pProbe->nColumn; nEq++){
      int j = pProbe->aiColumn[nEq];
      pTerm = findTerm(pWC, iCur, j, notReady, eqTermMask, pProbe);
      if( pTerm==0 ) break;
      wsFlags |= (WHERE_COLUMN_EQ|WHERE_ROWID_EQ);
      testcase( pTerm->pWC!=pWC );
      if( pTerm->eOperator & WO_IN ){
        Expr *pExpr = pTerm->pExpr;
        wsFlags |= WHERE_COLUMN_IN;
        if( ExprHasProperty(pExpr, EP_xIsSelect) ){
................................................................................
      testcase( wsFlags & WHERE_COLUMN_IN );
      testcase( wsFlags & WHERE_COLUMN_NULL );
      if( (wsFlags & (WHERE_COLUMN_IN|WHERE_COLUMN_NULL))==0 ){
        wsFlags |= WHERE_UNIQUE;
      }
    }else if( pProbe->bUnordered==0 ){
      int j = (nEq==pProbe->nColumn ? -1 : pProbe->aiColumn[nEq]);
      if( findTerm(pWC, iCur, j, notReady, WO_LT|WO_LE|WO_GT|WO_GE, pProbe) ){
        WhereTerm *pTop = findTerm(pWC, iCur, j, notReady, WO_LT|WO_LE, pProbe);
        WhereTerm *pBtm = findTerm(pWC, iCur, j, notReady, WO_GT|WO_GE, pProbe);
        whereRangeScanEst(pParse, pProbe, nEq, pBtm, pTop, &rangeDiv);
        if( pTop ){
          nBound = 1;
          wsFlags |= WHERE_TOP_LIMIT;
          used |= pTop->prereqRight;
          testcase( pTop->pWC!=pWC );
        }
................................................................................
    ** order of the DISTINCT expressions, clear bDist and set the appropriate
    ** flags in wsFlags. */
    if( isDistinctIndex(pParse, pWC, pProbe, iCur, pDistinct, nEq) ){
      bDist = 0;
      wsFlags |= WHERE_ROWID_RANGE|WHERE_COLUMN_RANGE|WHERE_DISTINCT;
    }

    /* If currently calculating the cost of using an index (not the PK
    ** index), determine if all required column data may be obtained without 
    ** using the main table (i.e. if the index is a covering
    ** index for this query). If it is, set the WHERE_IDX_ONLY flag in
    ** wsFlags. Otherwise, set the bLookup variable to true.  
    **
    ** TODO: Not clear if this optimization can be applied in SQLite 4. Fix
    ** this block once that is figured out.
    */
#if 0
    if( wsFlags ){
      Bitmask m = pSrc->colUsed;
      int j;
      for(j=0; j<pProbe->nColumn; j++){
        int x = pProbe->aiColumn[j];
        if( x<BMS-1 ){
          m &= ~(((Bitmask)1)<<x);
        }
      }
      if( m==0 ){
        wsFlags |= WHERE_IDX_ONLY;
      }else{
        bLookup = 1;
      }
    }
#endif
    bLookup = (pProbe->eIndexType!=SQLITE_INDEX_PRIMARYKEY);

    /*
    ** Estimate the number of rows of output.  For an "x IN (SELECT...)"
    ** constraint, do not let the estimate exceed half the rows in the table.
    */
    nRow = (double)(aiRowEst[nEq] * nInMul);
    if( bInEst && nRow*2>aiRowEst[0] ){
................................................................................
      ** decision and one which we expect to revisit in the future.  But
      ** it seems to be working well enough at the moment.
      */
      cost = aiRowEst[0]*4;
    }else{
      log10N = estLog(aiRowEst[0]);
      cost = nRow;

      if( bLookup ){
        /* For an index lookup followed by a table lookup:
        **    nInMul index searches to find the start of each index range
        **  + nRow steps through the index
        **  + nRow table searches to lookup the table entry using the PK
        */
        cost += (nInMul + nRow)*log10N;
      }else{
        /* For a covering index:
        **     nInMul index searches to find the initial entry 
        **   + nRow steps through the index







        */
        cost += nInMul*log10N;
      }
    }

    /* Add in the estimated cost of sorting the result.  Actual experimental
    ** measurements of sorting performance in SQLite show that sorting time
................................................................................
      if( nRow<2 ) nRow = 2;
    }


    WHERETRACE((
      "%s(%s): nEq=%d nInMul=%d rangeDiv=%d bSort=%d bLookup=%d wsFlags=0x%x\n"
      "         notReady=0x%llx log10N=%.1f nRow=%.1f cost=%.1f used=0x%llx\n",
      pSrc->pTab->zName, pProbe->zName,
      nEq, nInMul, (int)rangeDiv, bSort, bLookup, wsFlags,
      notReady, log10N, nRow, cost, used
    ));

    /* If this index is the best we have seen so far, then record this
    ** index and its cost in the pCost structure.
    */
    if( (pProbe==pFirst || wsFlags)
     && (cost<pCost->rCost || (cost<=pCost->rCost && nRow<pCost->plan.nRow))
    ){
      pCost->rCost = cost;
      pCost->used = used;
      pCost->plan.nRow = nRow;
      pCost->plan.wsFlags = (wsFlags&wsFlagMask);
      pCost->plan.nEq = nEq;
      pCost->plan.u.pIdx = pProbe;
    }

    /* If there was an INDEXED BY or NOT INDEXED clause, only one index is
    ** considered. */
    if( pSrc->pIndex || pSrc->notIndexed ) break;

    /* Reset masks for the next index in the loop */
    wsFlagMask = ~(WHERE_ROWID_EQ|WHERE_ROWID_RANGE);
    eqTermMask = idxEqTermMask;
  }

  /* If there is no ORDER BY clause and the SQLITE_ReverseOrder flag
................................................................................
    int nConstraint;             /* Number of constraint terms */
    Index *pIdx;                 /* The index we will be using */
    int iIdxCur;                 /* The VDBE cursor for the index */
    int nExtraReg = 0;           /* Number of extra registers needed */
    int op;                      /* Instruction opcode */
    char *zStartAff;             /* Affinity for start of range constraint */
    char *zEndAff;               /* Affinity for end of range constraint */
    int regEndKey;               /* Register for end-key */

    pIdx = pLevel->plan.u.pIdx;
    iIdxCur = pLevel->iIdxCur;
    k = (nEq==pIdx->nColumn ? -1 : pIdx->aiColumn[nEq]);

    /* If this loop satisfies a sort order (pOrderBy) request that 
    ** was passed to this function to implement a "SELECT min(x) ..." 
................................................................................
    testcase( op==OP_Last );
    testcase( op==OP_SeekGt );
    testcase( op==OP_SeekGe );
    testcase( op==OP_SeekLe );
    testcase( op==OP_SeekLt );
    sqlite4VdbeAddOp4Int(v, op, iIdxCur, addrNxt, regBase, nConstraint);

    /* Set variable op to the instruction required to determine if the
    ** cursor is passed the end of the range. If the range is unbounded,
    ** then set op to OP_Noop. Nothing to do in this case.  */
    op = aEndOp[(pRangeEnd || nEq) * (1 + bRev)];
    testcase( op==OP_Noop );
    testcase( op==OP_IdxGE );
    testcase( op==OP_IdxLT );
    if( op!=OP_Noop ){

      /* If there is an inequality at the end of this range, compute its
      ** value here.  */
      nConstraint = nEq;
      if( pRangeEnd ){
        Expr *pRight = pRangeEnd->pExpr->pRight;
        sqlite4ExprCacheRemove(pParse, regBase+nEq, 1);
        sqlite4ExprCode(pParse, pRight, regBase+nEq);
        if( (pRangeEnd->wtFlags & TERM_VNULL)==0 ){
          sqlite4ExprCodeIsNullJump(v, pRight, regBase+nEq, addrNxt);
        }
        if( zEndAff ){
          if( sqlite4CompareAffinity(pRight, zEndAff[nEq])==SQLITE_AFF_NONE){
            /* Since the comparison is to be performed with no conversions
             ** applied to the operands, set the affinity to apply to pRight to 
             ** SQLITE_AFF_NONE.  */
            zEndAff[nEq] = SQLITE_AFF_NONE;
          }
          if( sqlite4ExprNeedsNoAffinityChange(pRight, zEndAff[nEq]) ){
            zEndAff[nEq] = SQLITE_AFF_NONE;
          }
        }  
        codeApplyAffinity(pParse, regBase, nEq+1, zEndAff);
        nConstraint++;
        testcase( pRangeEnd->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
      }

      /* Now compute an end-key using OP_MakeKey */
      regEndKey = ++pParse->nMem;
      sqlite4VdbeAddOp2(v, OP_MakeKey, iIdxCur, regEndKey);
      sqlite4VdbeAddOp3(v, OP_MakeRecord, regBase, nConstraint, 0);
    }

    sqlite4DbFree(pParse->db, zStartAff);
    sqlite4DbFree(pParse->db, zEndAff);

    /* Top of the loop body */
    pLevel->p2 = sqlite4VdbeCurrentAddr(v);






    if( op!=OP_Noop ){
      /* XXX */
      sqlite4VdbeAddOp4Int(v, op, iIdxCur, addrNxt, regEndKey, nConstraint);
      sqlite4VdbeChangeP5(v, endEq!=bRev ?1:0);
    }

    /* If there are inequality constraints, check that the value
    ** of the table column that the inequality contrains is not NULL.
    ** If it is, jump to the next iteration of the loop.
    */
................................................................................
      sqlite4VdbeAddOp2(v, OP_IsNull, r1, addrCont);
    }
    sqlite4ReleaseTempReg(pParse, r1);

    /* Seek the table cursor, if required */
    disableTerm(pLevel, pRangeStart);
    disableTerm(pLevel, pRangeEnd);
    if( pIdx->eIndexType!=SQLITE_INDEX_PRIMARYKEY ){
      assert( 0 );
      iRowidReg = iReleaseReg = sqlite4GetTempReg(pParse);
      sqlite4VdbeAddOp2(v, OP_IdxRowid, iIdxCur, iRowidReg);
      sqlite4ExprCacheStore(pParse, iCur, -1, iRowidReg);
      sqlite4VdbeAddOp2(v, OP_Seek, iCur, iRowidReg);  /* Deferred seek */
    }

    /* Record the instruction used to terminate the loop. Disable 
................................................................................
      pLevel->op = OP_Noop;
    }else if( bRev ){
      pLevel->op = OP_Prev;
    }else{
      pLevel->op = OP_Next;
    }
    pLevel->p1 = iIdxCur;

  }else

#ifndef SQLITE_OMIT_OR_OPTIMIZATION
  if( pLevel->plan.wsFlags & WHERE_MULTI_OR ){
    /* Case 4:  Two or more separately indexed terms connected by OR
    **
    ** Example:
................................................................................
      int iCur = pTabItem->iCursor;
      sqlite4VdbeAddOp4(v, OP_VOpen, iCur, 0, 0, pVTab, P4_VTAB);
    }else
#endif
    if( (pLevel->plan.wsFlags & WHERE_IDX_ONLY)==0
         && (wctrlFlags & WHERE_OMIT_OPEN_CLOSE)==0 ){
      int op = pWInfo->okOnePass ? OP_OpenWrite : OP_OpenRead;
      sqlite4OpenPrimaryKey(pParse, pTabItem->iCursor, iDb, pTab, op);
      testcase( pTab->nCol==BMS-1 );
      testcase( pTab->nCol==BMS );
#if 0
      if( !pWInfo->okOnePass && pTab->nCol<BMS ){
        Bitmask b = pTabItem->colUsed;
        int n = 0;
        for(; b; b=b>>1, n++){}
        sqlite4VdbeChangeP4(v, sqlite4VdbeCurrentAddr(v)-1, 
                            SQLITE_INT_TO_PTR(n), P4_INT32);
        assert( n<=pTab->nCol );
      }
#endif
    }else{
      sqlite4TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);
    }
#ifndef SQLITE_OMIT_AUTOMATIC_INDEX
    if( (pLevel->plan.wsFlags & WHERE_TEMP_INDEX)!=0 ){
      constructAutomaticIndex(pParse, pWC, pTabItem, notReady, pLevel);
    }else
#endif
    if( (pLevel->plan.wsFlags & WHERE_INDEXED)!=0 ){
      Index *pIx = pLevel->plan.u.pIdx;
      if( pIx->eIndexType==SQLITE_INDEX_PRIMARYKEY ){
        pLevel->iIdxCur = pTabItem->iCursor;
      }else{
        KeyInfo *pKey = sqlite4IndexKeyinfo(pParse, pIx);
        int iIdxCur = pLevel->iIdxCur;
        assert( pIx->pSchema==pTab->pSchema );
        assert( iIdxCur>=0 );
        sqlite4VdbeAddOp4(v, OP_OpenRead, iIdxCur, pIx->tnum, iDb,
            (char*)pKey, P4_KEYINFO_HANDOFF);
        VdbeComment((v, "%s", pIx->zName));
      }
    }
    sqlite4CodeVerifySchema(pParse, iDb);
    notReady &= ~getMask(pWC->pMaskSet, pTabItem->iCursor);
  }
  pWInfo->iTop = sqlite4VdbeCurrentAddr(v);
  if( db->mallocFailed ) goto whereBeginError;

................................................................................
     && (pWInfo->wctrlFlags & WHERE_OMIT_OPEN_CLOSE)==0
    ){
      int ws = pLevel->plan.wsFlags;
      if( !pWInfo->okOnePass && (ws & WHERE_IDX_ONLY)==0 ){
        sqlite4VdbeAddOp1(v, OP_Close, pTabItem->iCursor);
      }
      if( (ws & WHERE_INDEXED)!=0 && (ws & WHERE_TEMP_INDEX)==0 ){
        if( pLevel->iIdxCur!=pTabItem->iCursor ){
          sqlite4VdbeAddOp1(v, OP_Close, pLevel->iIdxCur);
        }
      }
    }

    /* If this scan uses an index, make code substitutions to read data
    ** from the index in preference to the table. Sometimes, this means
    ** the table need never be read from. This is a performance boost,
    ** as the vdbe level waits until the table is read before actually

# 2012 April 02
#
# 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 were used while developing the SQLite 4 code. 
#
set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix simple

#set sqlite_where_trace 1

do_execsql_test 1.0 { 
  PRAGMA table_info = sqlite_master
} {
    0 type text        0 {} 0 
    1 name text        0 {} 0 
    2 tbl_name text    0 {} 0 
    3 rootpage integer 0 {} 0 
    4 sql text         0 {} 0 
}

do_execsql_test 1.1 { SELECT * FROM sqlite_master } {}

#explain { CREATE TABLE t1(a, b) }
#execsql { PRAGMA kv_trace = 1 }
#execsql { PRAGMA vdbe_trace = 1 }

do_execsql_test 1.2 { 
  CREATE TABLE t1(a, b);
  PRAGMA table_info = t1;
} {
    0 a {} 0 {} 0 
    1 b {} 0 {} 0 
}

do_execsql_test 1.3 { 
  CREATE TABLE t2(x, y);
  PRAGMA table_info = t2;
} {
    0 x {} 0 {} 0 
    1 y {} 0 {} 0 
}

do_execsql_test 1.4 { 
  CREATE TABLE t3(k PRIMARY KEY, v);
  PRAGMA table_info = t3;
} {
    0 k {} 0 {} 1 
    1 v {} 0 {} 0 
}

do_execsql_test 1.5 { 
  SELECT name, rootpage FROM sqlite_master 
} {t1 2 t2 3 t3 4}

#-------------------------------------------------------------------------
reset_db

do_execsql_test 2.1 { 
  CREATE TABLE t1(k PRIMARY KEY, v);
  CREATE TABLE t2(x, y); 
} {}

do_execsql_test 2.2.1 { INSERT INTO t1 VALUES('a', 'AAA') }
do_execsql_test 2.2.2 { SELECT * FROM t1 } {a AAA}
do_execsql_test 2.2.3 { INSERT INTO t1 VALUES('b', 'BBB') }
do_execsql_test 2.2.4 { SELECT * FROM t1 } {a AAA b BBB}

do_execsql_test 2.3.1 { INSERT INTO t2 VALUES('123', '456') }
do_execsql_test 2.3.2 { SELECT * FROM t2 } {123 456}
do_execsql_test 2.3.3 { INSERT INTO t2 VALUES('789', '0ab') }
do_execsql_test 2.3.4 { SELECT * FROM t2 } {123 456 789 0ab}

do_catchsql_test 2.2.5 {
  INSERT INTO t1 VALUES('a', 'CCC')
} {1 {column k is not unique}}

#-------------------------------------------------------------------------
reset_db

do_execsql_test 3.1 { CREATE TABLE t1(k PRIMARY KEY, v UNIQUE) }

do_execsql_test 3.2 { 
  SELECT * FROM sqlite_master
} {
  table t1                    t1 2 {CREATE TABLE t1(k PRIMARY KEY, v UNIQUE)} 
  index sqlite_autoindex_t1_2 t1 3 {}
}

#explain { INSERT INTO t1 VALUES('one', '111') }
#execsql { PRAGMA vdbe_trace = 1 }
#execsql { PRAGMA kv_trace = 1 }
#
do_execsql_test 3.3 { INSERT INTO t1 VALUES('one', '111') } {}


#-------------------------------------------------------------------------
reset_db

do_execsql_test 4.1 { CREATE TABLE t1(k PRIMARY KEY, v) }
do_execsql_test 4.2 { CREATE INDEX i1 ON t1(v) }

do_execsql_test 4.3 { 
  SELECT * FROM sqlite_master
} {
  table t1 t1 2 {CREATE TABLE t1(k PRIMARY KEY, v)} 
  index i1 t1 3 {CREATE INDEX i1 ON t1(v)}
}
do_execsql_test 4.4 { INSERT INTO t1 VALUES('one', '111') } {}
do_execsql_test 4.5 { SELECT * FROM t1 } {one 111} 

do_execsql_test 4.6 { PRAGMA integrity_check } {ok}


#-------------------------------------------------------------------------
reset_db

do_execsql_test 5.1 { CREATE TABLE t1(k, v UNIQUE) }
do_execsql_test 5.2 { CREATE INDEX i1 ON t1(v) }

do_execsql_test 5.3 { 
  SELECT * FROM sqlite_master
} {
  table t1                    t1 3 {CREATE TABLE t1(k, v UNIQUE)} 
  index sqlite_autoindex_t1_1 t1 2 {}
  index i1                    t1 4 {CREATE INDEX i1 ON t1(v)}
}

do_execsql_test 5.3 { INSERT INTO t1 VALUES('one', '111') } {}
do_execsql_test 5.4 { SELECT * FROM t1 } {one 111} 
do_execsql_test 5.5 { PRAGMA integrity_check } {ok}

#-------------------------------------------------------------------------
reset_db

do_execsql_test 6.1 { 
  CREATE TABLE t1(k PRIMARY KEY, v);
  CREATE INDEX i1 ON t1(v);
  INSERT INTO t1 VALUES('one', 1);
  INSERT INTO t1 VALUES('two', 2);
  INSERT INTO t1 VALUES('three', 3);
  INSERT INTO t1 VALUES('four', 4);
  INSERT INTO t1 VALUES('five', 5);
}

do_execsql_test 6.2 { 
  SELECT * FROM t1
} {five 5 four 4 one 1 three 3 two 2}

do_execsql_test 6.3 { 
  CREATE TABLE t2(x PRIMARY KEY, y);
  INSERT INTO t2 SELECT v, k FROM t1;
  SELECT * FROM t2
} {1 one 2 two 3 three 4 four 5 five}
do_execsql_test 6.4 { PRAGMA integrity_check } {ok}

do_execsql_test 6.5 { 
  CREATE TABLE t3(a, b);
  INSERT INTO t3 SELECT k, v FROM t1;
  SELECT * FROM t3
} {five 5 four 4 one 1 three 3 two 2}

do_execsql_test 6.6 { 
  INSERT INTO t3 SELECT a, b FROM t3;
  SELECT * FROM t3;
} {five 5 four 4 one 1 three 3 two 2 five 5 four 4 one 1 three 3 two 2}

do_execsql_test 6.7 { PRAGMA integrity_check } {ok}
do_execsql_test 6.8 { CREATE INDEX i2 ON t3(a) }
do_execsql_test 6.9 { PRAGMA integrity_check } {ok}

#-------------------------------------------------------------------------
reset_db

do_execsql_test 7.1 {
  CREATE TABLE t1(a, b);
  CREATE INDEX i1 ON t1(a);
}
do_execsql_test 7.2.1 { INSERT INTO t1 VALUES('xyz', '123') }
do_execsql_test 7.2.2 { INSERT INTO t1 VALUES('xyz', '123') }
do_execsql_test 7.2.3 { INSERT INTO t1 VALUES('xyz', '123') }

do_execsql_test 7.3 {
  SELECT * FROM t1;
} {xyz 123 xyz 123 xyz 123}

do_execsql_test 7.4 { PRAGMA integrity_check } {ok}

#-------------------------------------------------------------------------
reset_db

do_execsql_test 8.1 {
  CREATE TABLE t1(a PRIMARY KEY, b);
  INSERT INTO t1 VALUES('a', 'b');
}

do_execsql_test 8.2 { DELETE FROM t1 WHERE b = 'b' }
do_execsql_test 8.3 { SELECT * FROM t1 } {}
do_execsql_test 8.4 {
  INSERT INTO t1 VALUES('a', 'A');
  INSERT INTO t1 VALUES('b', 'B');
  INSERT INTO t1 VALUES('c', 'A');
  INSERT INTO t1 VALUES('d', 'B');
  INSERT INTO t1 VALUES('e', 'A');
  INSERT INTO t1 VALUES('f', 'B');
}
do_execsql_test 8.5 { DELETE FROM t1 WHERE b = 'B' }
do_execsql_test 8.6 { SELECT * FROM t1 } {a A c A e A}

#-------------------------------------------------------------------------
reset_db

do_execsql_test 9.1 {
  CREATE TABLE t1(a, b);
  CREATE INDEX i1 ON t1(b);
}

do_execsql_test 9.2 {
  INSERT INTO t1 VALUES('a', 'A');
  INSERT INTO t1 VALUES('b', 'B');
  INSERT INTO t1 VALUES('c', 'A');
  INSERT INTO t1 VALUES('d', 'B');
  INSERT INTO t1 VALUES('e', 'A');
  INSERT INTO t1 VALUES('f', 'B');
}
do_execsql_test 9.3 { DELETE FROM t1 WHERE +b = 'B' }
do_execsql_test 9.4 { SELECT * FROM t1 } {a A c A e A}
do_execsql_test 9.5 { PRAGMA integrity_check } {ok}

#-------------------------------------------------------------------------
reset_db

do_execsql_test 10.1 {
  CREATE TABLE t1(a, b);
  CREATE INDEX i1 ON t1(b);
}
do_execsql_test 10.2 {
  INSERT INTO t1 VALUES(1, 2);
  INSERT INTO t1 VALUES(3, 4);
}

# explain { UPDATE t1 SET b = 10 WHERE a=3 }
#  execsql { PRAGMA vdbe_trace = 1 }

do_execsql_test 10.3 { 
  UPDATE t1 SET b = 10 WHERE a=3;
  SELECT * FROM t1;
} {1 2 3 10}

do_execsql_test 10.4 { PRAGMA integrity_check } {ok}
execsql { PRAGMA kvdump }

finish_test

#proc populate_t1 {} {
#  db eval {
#    INSERT INTO t1(a, b) VALUES(4, 'four');
#    INSERT INTO t1(a, b) VALUES(9, 'nine');
#    INSERT INTO t1(a, b) VALUES(5, 'five');
#    INSERT INTO t1(a, b) VALUES(1, 'one');
#    INSERT INTO t1(a, b) VALUES(7, 'seven');
#    INSERT INTO t1(a, b) VALUES(8, 'eight');
#    INSERT INTO t1(a, b) VALUES(2, 'two');
#    INSERT INTO t1(a, b) VALUES(3, 'three');
#    INSERT INTO t1(a, b) VALUES(6, 'six');
#    INSERT INTO t1(a, b) VALUES(10, 'ten');
#  }
#}
#
#foreach {t schema} {
#  1 "CREATE TABLE t1(a, b)"
#  2 "CREATE TABLE t1(a, b); CREATE INDEX i1 ON t1(a);"
#  3 "CREATE TABLE t1(a, b); CREATE INDEX i1 ON t1(b);"
#  4 "CREATE TABLE t1(a PRIMARY KEY, b)"
#} {
#
#  do_test 1.$t.0 {
#    reset_db
#    execsql $schema
#    populate_t1
#  } {}
#
#  foreach {u sql res} {
#    1 "SELECT * FROM t1 WHERE a = 7"        {7 seven}
#    2 "SELECT * FROM t1 WHERE b = 'seven'"  {7 seven}
#  } {
#    do_execsql_test 1.$t.$u $sql $res
#  }
#}

finish_test

# Set the precision of FP arithmatic used by the interpreter. And 
# configure SQLite to take database file locks on the page that begins
# 64KB into the database file instead of the one 1GB in. This means
# the code that handles that special case can be tested without creating
# very large database files.
#
set tcl_precision 15
sqlite4_test_control_pending_byte 0x0010000


# If the pager codec is available, create a wrapper for the [sqlite4] 
# command that appends "-key {xyzzy}" to the command line. i.e. this:
#
#     sqlite4 db test.db
#
................................................................................

  # Install the malloc layer used to inject OOM errors. And the 'automatic'
  # extensions. This only needs to be done once for the process.
  #
  sqlite4_shutdown 
  install_malloc_faultsim 1 
  sqlite4_initialize
  autoinstall_test_functions

  # If the --binarylog option was specified, create the logging VFS. This
  # call installs the new VFS as the default for all SQLite connections.
  #
  if {$cmdlinearg(binarylog)} {
    vfslog new binarylog {} vfslog.bin
  }
................................................................................

  set omitList [set_test_counter omit_list]

  catch {db close}
  catch {db2 close}
  catch {db3 close}

  vfs_unlink_test
  sqlite4 db {}
  # sqlite4_clear_tsd_memdebug
  db close
  sqlite4_reset_auto_extension

  sqlite4_soft_heap_limit 0
  set nTest [incr_ntest]
  set nErr [set_test_counter errors]

  puts "$nErr errors out of $nTest tests"
  if {$nErr>0} {

# Set the precision of FP arithmatic used by the interpreter. And 
# configure SQLite to take database file locks on the page that begins
# 64KB into the database file instead of the one 1GB in. This means
# the code that handles that special case can be tested without creating
# very large database files.
#
set tcl_precision 15
#sqlite4_test_control_pending_byte 0x0010000


# If the pager codec is available, create a wrapper for the [sqlite4] 
# command that appends "-key {xyzzy}" to the command line. i.e. this:
#
#     sqlite4 db test.db
#
................................................................................

  # Install the malloc layer used to inject OOM errors. And the 'automatic'
  # extensions. This only needs to be done once for the process.
  #
  sqlite4_shutdown 
  install_malloc_faultsim 1 
  sqlite4_initialize
  #autoinstall_test_functions

  # If the --binarylog option was specified, create the logging VFS. This
  # call installs the new VFS as the default for all SQLite connections.
  #
  if {$cmdlinearg(binarylog)} {
    vfslog new binarylog {} vfslog.bin
  }
................................................................................

  set omitList [set_test_counter omit_list]

  catch {db close}
  catch {db2 close}
  catch {db3 close}

  #vfs_unlink_test
  sqlite4 db {}
  # sqlite4_clear_tsd_memdebug
  db close
  #sqlite4_reset_auto_extension

  sqlite4_soft_heap_limit 0
  set nTest [incr_ntest]
  set nErr [set_test_counter errors]

  puts "$nErr errors out of $nTest tests"
  if {$nErr>0} {