SQLite

      **   if( idx(1) != regPrev(1) ) goto chng_addr_1
      **   ...
      **   regChng = N
      **   goto endDistinctTest
      */
      sqlite3VdbeAddOp0(v, OP_Goto);
      addrNextRow = sqlite3VdbeCurrentAddr(v);
      if( nColTest==1 && pIdx->nKeyCol==1 && pIdx->onError!=OE_None ){
      if( nColTest==1 && pIdx->nKeyCol==1 && IsUniqueIndex(pIdx) ){
        /* For a single-column UNIQUE index, once we have found a non-NULL
        ** row, we know that all the rest will be distinct, so skip 
        ** subsequent distinctness tests. */
        sqlite3VdbeAddOp2(v, OP_NotNull, regPrev, endDistinctTest);
        VdbeCoverage(v);
      }
      for(i=0; i<nColTest; i++){

  }

  /* If the client is reading  or writing an index and the schema is
  ** not loaded, then it is too difficult to actually check to see if
  ** the correct locks are held.  So do not bother - just return true.
  ** This case does not come up very often anyhow.
  */
  if( isIndex && (!pSchema || (pSchema->flags&DB_SchemaLoaded)==0) ){
  if( isIndex && (!pSchema || (pSchema->schemaFlags&DB_SchemaLoaded)==0) ){
    return 1;
  }

  /* Figure out the root-page that the lock should be held on. For table
  ** b-trees, this is just the root page of the b-tree being read or
  ** written. For index b-trees, it is the root page of the associated
  ** table.  */

      assert( pTable->aCol==0 );
      pTable->nCol = pSelTab->nCol;
      pTable->aCol = pSelTab->aCol;
      pSelTab->nCol = 0;
      pSelTab->aCol = 0;
      sqlite3DeleteTable(db, pSelTab);
      assert( sqlite3SchemaMutexHeld(db, 0, pTable->pSchema) );
      pTable->pSchema->flags |= DB_UnresetViews;
      pTable->pSchema->schemaFlags |= DB_UnresetViews;
    }else{
      pTable->nCol = 0;
      nErr++;
    }
    sqlite3SelectDelete(db, pSel);
  } else {
    nErr++;

  if( memRootPage<0 ) sqlite3VdbeAddOp2(v, OP_Clear, tnum, iDb);
  sqlite3VdbeAddOp4(v, OP_OpenWrite, iIdx, tnum, iDb, 
                    (char *)pKey, P4_KEYINFO);
  sqlite3VdbeChangeP5(v, OPFLAG_BULKCSR|((memRootPage>=0)?OPFLAG_P2ISREG:0));

  addr1 = sqlite3VdbeAddOp2(v, OP_SorterSort, iSorter, 0); VdbeCoverage(v);
  assert( pKey!=0 || db->mallocFailed || pParse->nErr );
  if( pIndex->onError!=OE_None && pKey!=0 ){
  if( IsUniqueIndex(pIndex) && pKey!=0 ){
    int j2 = sqlite3VdbeCurrentAddr(v) + 3;
    sqlite3VdbeAddOp2(v, OP_Goto, 0, j2);
    addr2 = sqlite3VdbeCurrentAddr(v);
    sqlite3VdbeAddOp4Int(v, OP_SorterCompare, iSorter, j2, regRecord,
                         pIndex->nKeyCol); VdbeCoverage(v);
    sqlite3UniqueConstraint(pParse, OE_Abort, pIndex);
  }else{

    ** If there are different collating sequences or if the columns of
    ** 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( IsUniqueIndex(pIdx) );
      assert( pIdx->idxType!=SQLITE_IDXTYPE_APPDEF );
      assert( pIndex->onError!=OE_None );
      assert( IsUniqueIndex(pIndex) );

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

  ** 6 and each subsequent value (if any) is 5.  */
  memcpy(&a[1], aVal, nCopy*sizeof(LogEst));
  for(i=nCopy+1; i<=pIdx->nKeyCol; i++){
    a[i] = 23;                    assert( 23==sqlite3LogEst(5) );
  }

  assert( 0==sqlite3LogEst(1) );
  if( pIdx->onError!=OE_None ) a[pIdx->nKeyCol] = 0;
  if( IsUniqueIndex(pIdx) ) a[pIdx->nKeyCol] = 0;
}

/*
** This routine will drop an existing named index.  This routine
** implements the DROP INDEX statement.
*/
void sqlite3DropIndex(Parse *pParse, SrcList *pName, int ifExists){

  for(pElem=sqliteHashFirst(&temp1); pElem; pElem=sqliteHashNext(pElem)){
    Table *pTab = sqliteHashData(pElem);
    sqlite3DeleteTable(0, pTab);
  }
  sqlite3HashClear(&temp1);
  sqlite3HashClear(&pSchema->fkeyHash);
  pSchema->pSeqTab = 0;
  if( pSchema->flags & DB_SchemaLoaded ){
  if( pSchema->schemaFlags & DB_SchemaLoaded ){
    pSchema->iGeneration++;
    pSchema->flags &= ~DB_SchemaLoaded;
    pSchema->schemaFlags &= ~DB_SchemaLoaded;
  }
}

/*
** Find and return the schema associated with a BTree.  Create
** a new one if necessary.
*/

  if( op==TK_REGISTER ) op = p->op2;
  switch( op ){
    case TK_INTEGER:
    case TK_STRING:
    case TK_FLOAT:
    case TK_BLOB:
      return 0;
    case TK_COLUMN:
      assert( p->pTab!=0 );
      return p->iColumn>=0 && p->pTab->aCol[p->iColumn].notNull==0;
    default:
      return 1;
  }
}

/*
** Return TRUE if the given expression is a constant which would be

** address of the new instruction.
*/
int sqlite3CodeOnce(Parse *pParse){
  Vdbe *v = sqlite3GetVdbe(pParse);      /* Virtual machine being coded */
  return sqlite3VdbeAddOp1(v, OP_Once, pParse->nOnce++);
}

/*
** Generate code that checks the left-most column of index table iCur to see if
** it contains any NULL entries.  Cause the register at regHasNull to be set
** to a non-NULL value if iCur contains no NULLs.  Cause register regHasNull
** to be set to NULL if iCur contains one or more NULL values.
*/
static void sqlite3SetHasNullFlag(Vdbe *v, int iCur, int regHasNull){
  int j1;
  sqlite3VdbeAddOp2(v, OP_Integer, 0, regHasNull);
  j1 = sqlite3VdbeAddOp1(v, OP_Rewind, iCur); VdbeCoverage(v);
  sqlite3VdbeAddOp3(v, OP_Column, iCur, 0, regHasNull);
  sqlite3VdbeChangeP5(v, OPFLAG_TYPEOFARG);
  VdbeComment((v, "first_entry_in(%d)", iCur));
  sqlite3VdbeJumpHere(v, j1);
}


#ifndef SQLITE_OMIT_SUBQUERY
/*
** The argument is an IN operator with a list (not a subquery) on the 
** right-hand side.  Return TRUE if that list is constant.
*/
static int sqlite3InRhsIsConstant(Expr *pIn){
  Expr *pLHS;
  int res;
  assert( !ExprHasProperty(pIn, EP_xIsSelect) );
  pLHS = pIn->pLeft;
  pIn->pLeft = 0;
  res = sqlite3ExprIsConstant(pIn);
  pIn->pLeft = pLHS;
  return res;
}
#endif

/*
** This function is used by the implementation of the IN (...) operator.
** The pX parameter is the expression on the RHS of the IN operator, which
** might be either a list of expressions or a subquery.
**
** The job of this routine is to find or create a b-tree object that can
** be used either to test for membership in the RHS set or to iterate through
** all members of the RHS set, skipping duplicates.
**
** A cursor is opened on the b-tree object that the RHS of the IN operator
** A cursor is opened on the b-tree object that is the RHS of the IN operator
** and pX->iTable is set to the index of that cursor.
**
** The returned value of this function indicates the b-tree type, as follows:
**
**   IN_INDEX_ROWID      - The cursor was opened on a database table.
**   IN_INDEX_INDEX_ASC  - The cursor was opened on an ascending index.
**   IN_INDEX_INDEX_DESC - The cursor was opened on a descending index.
**   IN_INDEX_EPH        - The cursor was opened on a specially created and
**                         populated epheremal table.
**   IN_INDEX_NOOP       - No cursor was allocated.  The IN operator must be
**                         implemented as a sequence of comparisons.
**
** An existing b-tree might be used if the RHS expression pX is a simple
** subquery such as:
**
**     SELECT <column> FROM <table>
**
** If the RHS of the IN operator is a list or a more complex subquery, then
** an ephemeral table might need to be generated from the RHS and then
** pX->iTable made to point to the ephermeral table instead of an
** existing table.  
** existing table.
**
** The inFlags parameter must contain exactly one of the bits
** IN_INDEX_MEMBERSHIP or IN_INDEX_LOOP.  If inFlags contains
** IN_INDEX_MEMBERSHIP, then the generated table will be used for a
** fast membership test.  When the IN_INDEX_LOOP bit is set, the
** IN index will be used to loop over all values of the RHS of the
** IN operator.
**
** If the prNotFound parameter is 0, then the b-tree will be used to iterate
** through the set members, skipping any duplicates. In this case an
** epheremal table must be used unless the selected <column> is guaranteed
** When IN_INDEX_LOOP is used (and the b-tree will be used to iterate
** through the set members) then the b-tree must not contain duplicates.
** An epheremal table must be used unless the selected <column> is guaranteed
** to be unique - either because it is an INTEGER PRIMARY KEY or it
** has a UNIQUE constraint or UNIQUE index.
**
** If the prNotFound parameter is not 0, then the b-tree will be used 
** for fast set membership tests. In this case an epheremal table must 
** When IN_INDEX_MEMBERSHIP is used (and the b-tree will be used 
** for fast set membership tests) then an epheremal table must 
** be used unless <column> is an INTEGER PRIMARY KEY or an index can 
** be found with <column> as its left-most column.
**
** If the IN_INDEX_NOOP_OK and IN_INDEX_MEMBERSHIP are both set and
** if the RHS of the IN operator is a list (not a subquery) then this
** routine might decide that creating an ephemeral b-tree for membership
** testing is too expensive and return IN_INDEX_NOOP.  In that case, the
** calling routine should implement the IN operator using a sequence
** of Eq or Ne comparison operations.
**
** When the b-tree is being used for membership tests, the calling function
** needs to know whether or not the structure contains an SQL NULL 
** might need to know whether or not the RHS side of the IN operator
** value in order to correctly evaluate expressions like "X IN (Y, Z)".
** If there is any chance that the (...) might contain a NULL value at
** contains a NULL.  If prRhsHasNull is not a NULL pointer and 
** if there is any chance that the (...) might contain a NULL value at
** runtime, then a register is allocated and the register number written
** to *prNotFound. If there is no chance that the (...) contains a
** NULL value, then *prNotFound is left unchanged.
** to *prRhsHasNull. If there is no chance that the (...) contains a
** NULL value, then *prRhsHasNull is left unchanged.
**
** If a register is allocated and its location stored in *prNotFound, then
** If a register is allocated and its location stored in *prRhsHasNull, then
** its initial value is NULL.  If the (...) does not remain constant
** for the duration of the query (i.e. the SELECT within the (...)
** is a correlated subquery) then the value of the allocated register is
** the value in that register will be NULL if the b-tree contains one or more
** reset to NULL each time the subquery is rerun. This allows the
** caller to use vdbe code equivalent to the following:
**
**   if( register==NULL ){
**     has_null = <test if data structure contains null>
** NULL values, and it will be some non-NULL value if the b-tree contains no
**     register = 1
**   }
** NULL values.
**
** in order to avoid running the <test if data structure contains null>
** test more often than is necessary.
*/
#ifndef SQLITE_OMIT_SUBQUERY
int sqlite3FindInIndex(Parse *pParse, Expr *pX, int *prNotFound){
int sqlite3FindInIndex(Parse *pParse, Expr *pX, u32 inFlags, int *prRhsHasNull){
  Select *p;                            /* SELECT to the right of IN operator */
  int eType = 0;                        /* Type of RHS table. IN_INDEX_* */
  int iTab = pParse->nTab++;            /* Cursor of the RHS table */
  int mustBeUnique = (prNotFound==0);   /* True if RHS must be unique */
  int mustBeUnique;                     /* True if RHS must be unique */
  Vdbe *v = sqlite3GetVdbe(pParse);     /* Virtual machine being coded */

  assert( pX->op==TK_IN );
  mustBeUnique = (inFlags & IN_INDEX_LOOP)!=0;

  /* Check to see if an existing table or index can be used to
  ** satisfy the query.  This is preferable to generating a new 
  ** ephemeral table.
  */
  p = (ExprHasProperty(pX, EP_xIsSelect) ? pX->x.pSelect : 0);
  if( ALWAYS(pParse->nErr==0) && isCandidateForInOpt(p) ){

      ** it is not, it is not possible to use any index.
      */
      int affinity_ok = sqlite3IndexAffinityOk(pX, pTab->aCol[iCol].affinity);

      for(pIdx=pTab->pIndex; pIdx && eType==0 && affinity_ok; pIdx=pIdx->pNext){
        if( (pIdx->aiColumn[0]==iCol)
         && sqlite3FindCollSeq(db, ENC(db), pIdx->azColl[0], 0)==pReq
         && (!mustBeUnique || (pIdx->nKeyCol==1 && pIdx->onError!=OE_None))
         && (!mustBeUnique || (pIdx->nKeyCol==1 && IsUniqueIndex(pIdx)))
        ){
          int iAddr = sqlite3CodeOnce(pParse); VdbeCoverage(v);
          sqlite3VdbeAddOp3(v, OP_OpenRead, iTab, pIdx->tnum, iDb);
          sqlite3VdbeSetP4KeyInfo(pParse, pIdx);
          VdbeComment((v, "%s", pIdx->zName));
          assert( IN_INDEX_INDEX_DESC == IN_INDEX_INDEX_ASC+1 );
          eType = IN_INDEX_INDEX_ASC + pIdx->aSortOrder[0];

          if( prNotFound && !pTab->aCol[iCol].notNull ){
            *prNotFound = ++pParse->nMem;
            sqlite3VdbeAddOp2(v, OP_Null, 0, *prNotFound);
          if( prRhsHasNull && !pTab->aCol[iCol].notNull ){
            *prRhsHasNull = ++pParse->nMem;
            sqlite3SetHasNullFlag(v, iTab, *prRhsHasNull);
          }
          sqlite3VdbeJumpHere(v, iAddr);
        }
      }
    }
  }

  /* If no preexisting index is available for the IN clause
  ** and IN_INDEX_NOOP is an allowed reply
  ** and the RHS of the IN operator is a list, not a subquery
  ** and the RHS is not contant or has two or fewer terms,
  ** then it is not worth creating an ephermeral table to evaluate
  ** the IN operator so return IN_INDEX_NOOP.
  */
  if( eType==0
   && (inFlags & IN_INDEX_NOOP_OK)
   && !ExprHasProperty(pX, EP_xIsSelect)
   && (!sqlite3InRhsIsConstant(pX) || pX->x.pList->nExpr<=2)
  ){
    eType = IN_INDEX_NOOP;
  }
     

  if( eType==0 ){
    /* Could not found an existing table or index to use as the RHS b-tree.
    /* Could not find an existing table or index to use as the RHS b-tree.
    ** We will have to generate an ephemeral table to do the job.
    */
    u32 savedNQueryLoop = pParse->nQueryLoop;
    int rMayHaveNull = 0;
    eType = IN_INDEX_EPH;
    if( prNotFound ){
    if( inFlags & IN_INDEX_LOOP ){
      *prNotFound = rMayHaveNull = ++pParse->nMem;
      sqlite3VdbeAddOp2(v, OP_Null, 0, *prNotFound);
    }else{
      pParse->nQueryLoop = 0;
      if( pX->pLeft->iColumn<0 && !ExprHasProperty(pX, EP_xIsSelect) ){
        eType = IN_INDEX_ROWID;
      }
    }else if( prRhsHasNull ){
      *prRhsHasNull = rMayHaveNull = ++pParse->nMem;
    }
    sqlite3CodeSubselect(pParse, pX, rMayHaveNull, eType==IN_INDEX_ROWID);
    pParse->nQueryLoop = savedNQueryLoop;
  }else{
    pX->iTable = iTab;
  }
  return eType;

** to be of the form "<rowid> IN (?, ?, ?)", where <rowid> is a reference
** to some integer key column of a table B-Tree. In this case, use an
** intkey B-Tree to store the set of IN(...) values instead of the usual
** (slower) variable length keys B-Tree.
**
** If rMayHaveNull is non-zero, that means that the operation is an IN
** (not a SELECT or EXISTS) and that the RHS might contains NULLs.
** Furthermore, the IN is in a WHERE clause and that we really want
** to iterate over the RHS of the IN operator in order to quickly locate
** all corresponding LHS elements.  All this routine does is initialize
** the register given by rMayHaveNull to NULL.  Calling routines will take
** care of changing this register value to non-NULL if the RHS is NULL-free.
** All this routine does is initialize the register given by rMayHaveNull
** to NULL.  Calling routines will take care of changing this register
** value to non-NULL if the RHS is NULL-free.
**
** If rMayHaveNull is zero, that means that the subquery is being used
** for membership testing only.  There is no need to initialize any
** registers to indicate the presence or absence of NULLs on the RHS.
**
** For a SELECT or EXISTS operator, return the register that holds the
** result.  For IN operators or if an error occurs, the return value is 0.
*/
#ifndef SQLITE_OMIT_SUBQUERY
int sqlite3CodeSubselect(
  Parse *pParse,          /* Parsing context */
  Expr *pExpr,            /* The IN, SELECT, or EXISTS operator */
  int rMayHaveNull,       /* Register that records whether NULLs exist in RHS */
  int rHasNullFlag,       /* Register that records whether NULLs exist in RHS */
  int isRowid             /* If true, LHS of IN operator is a rowid */
){
  int testAddr = -1;                      /* One-time test address */
  int jmpIfDynamic = -1;                      /* One-time test address */
  int rReg = 0;                           /* Register storing resulting */
  Vdbe *v = sqlite3GetVdbe(pParse);
  if( NEVER(v==0) ) return 0;
  sqlite3ExprCachePush(pParse);

  /* This code must be run in its entirety every time it is encountered
  ** if any of the following is true:
  **
  **    *  The right-hand side is a correlated subquery
  **    *  The right-hand side is an expression list containing variables
  **    *  We are inside a trigger
  **
  ** If all of the above are false, then we can run this code just once
  ** save the results, and reuse the same result on subsequent invocations.
  */
  if( !ExprHasProperty(pExpr, EP_VarSelect) ){
    testAddr = sqlite3CodeOnce(pParse); VdbeCoverage(v);
    jmpIfDynamic = sqlite3CodeOnce(pParse); VdbeCoverage(v);
  }

#ifndef SQLITE_OMIT_EXPLAIN
  if( pParse->explain==2 ){
    char *zMsg = sqlite3MPrintf(
        pParse->db, "EXECUTE %s%s SUBQUERY %d", testAddr>=0?"":"CORRELATED ",
        pParse->db, "EXECUTE %s%s SUBQUERY %d", jmpIfDynamic>=0?"":"CORRELATED ",
        pExpr->op==TK_IN?"LIST":"SCALAR", pParse->iNextSelectId
    );
    sqlite3VdbeAddOp4(v, OP_Explain, pParse->iSelectId, 0, 0, zMsg, P4_DYNAMIC);
  }
#endif

  switch( pExpr->op ){
    case TK_IN: {
      char affinity;              /* Affinity of the LHS of the IN */
      int addr;                   /* Address of OP_OpenEphemeral instruction */
      Expr *pLeft = pExpr->pLeft; /* the LHS of the IN operator */
      KeyInfo *pKeyInfo = 0;      /* Key information */

      if( rMayHaveNull ){
        sqlite3VdbeAddOp2(v, OP_Null, 0, rMayHaveNull);
      }

      affinity = sqlite3ExprAffinity(pLeft);

      /* Whether this is an 'x IN(SELECT...)' or an 'x IN(<exprlist>)'
      ** expression it is handled the same way.  An ephemeral table is 
      ** filled with single-field index keys representing the results
      ** from the SELECT or the <exprlist>.
      **

      if( ExprHasProperty(pExpr, EP_xIsSelect) ){
        /* Case 1:     expr IN (SELECT ...)
        **
        ** Generate code to write the results of the select into the temporary
        ** table allocated and opened above.
        */
        Select *pSelect = pExpr->x.pSelect;
        SelectDest dest;
        ExprList *pEList;

        assert( !isRowid );
        sqlite3SelectDestInit(&dest, SRT_Set, pExpr->iTable);
        dest.affSdst = (u8)affinity;
        assert( (pExpr->iTable&0x0000FFFF)==pExpr->iTable );
        pExpr->x.pSelect->iLimit = 0;
        pSelect->iLimit = 0;
        testcase( pSelect->selFlags & SF_Distinct );
        pSelect->selFlags &= ~SF_Distinct;
        testcase( pKeyInfo==0 ); /* Caused by OOM in sqlite3KeyInfoAlloc() */
        if( sqlite3Select(pParse, pExpr->x.pSelect, &dest) ){
        if( sqlite3Select(pParse, pSelect, &dest) ){
          sqlite3KeyInfoUnref(pKeyInfo);
          return 0;
        }
        pEList = pExpr->x.pSelect->pEList;
        pEList = pSelect->pEList;
        assert( pKeyInfo!=0 ); /* OOM will cause exit after sqlite3Select() */
        assert( pEList!=0 );
        assert( pEList->nExpr>0 );
        assert( sqlite3KeyInfoIsWriteable(pKeyInfo) );
        pKeyInfo->aColl[0] = sqlite3BinaryCompareCollSeq(pParse, pExpr->pLeft,
                                                         pEList->a[0].pExpr);
      }else if( ALWAYS(pExpr->x.pList!=0) ){

          assert( sqlite3KeyInfoIsWriteable(pKeyInfo) );
          pKeyInfo->aColl[0] = sqlite3ExprCollSeq(pParse, pExpr->pLeft);
        }

        /* Loop through each expression in <exprlist>. */
        r1 = sqlite3GetTempReg(pParse);
        r2 = sqlite3GetTempReg(pParse);
        sqlite3VdbeAddOp2(v, OP_Null, 0, r2);
        if( isRowid ) sqlite3VdbeAddOp2(v, OP_Null, 0, r2);
        for(i=pList->nExpr, pItem=pList->a; i>0; i--, pItem++){
          Expr *pE2 = pItem->pExpr;
          int iValToIns;

          /* If the expression is not constant then we will need to
          ** disable the test that was generated above that makes sure
          ** this code only executes once.  Because for a non-constant
          ** expression we need to rerun this code each time.
          */
          if( testAddr>=0 && !sqlite3ExprIsConstant(pE2) ){
            sqlite3VdbeChangeToNoop(v, testAddr);
            testAddr = -1;
          if( jmpIfDynamic>=0 && !sqlite3ExprIsConstant(pE2) ){
            sqlite3VdbeChangeToNoop(v, jmpIfDynamic);
            jmpIfDynamic = -1;
          }

          /* Evaluate the expression and insert it into the temp table */
          if( isRowid && sqlite3ExprIsInteger(pE2, &iValToIns) ){
            sqlite3VdbeAddOp3(v, OP_InsertInt, pExpr->iTable, r2, iValToIns);
          }else{
            r3 = sqlite3ExprCodeTarget(pParse, pE2, r1);

      }
      rReg = dest.iSDParm;
      ExprSetVVAProperty(pExpr, EP_NoReduce);
      break;
    }
  }

  if( rHasNullFlag ){
    sqlite3SetHasNullFlag(v, pExpr->iTable, rHasNullFlag);
  }
  if( testAddr>=0 ){
    sqlite3VdbeJumpHere(v, testAddr);

  if( jmpIfDynamic>=0 ){
    sqlite3VdbeJumpHere(v, jmpIfDynamic);
  }
  sqlite3ExprCachePop(pParse);

  return rReg;
}
#endif /* SQLITE_OMIT_SUBQUERY */

#ifndef SQLITE_OMIT_SUBQUERY
/*
** Generate code for an IN expression.
**
**      x IN (SELECT ...)
**      x IN (value, value, ...)
**
** The left-hand side (LHS) is a scalar expression.  The right-hand side (RHS)
** is an array of zero or more values.  The expression is true if the LHS is
** contained within the RHS.  The value of the expression is unknown (NULL)
** if the LHS is NULL or if the LHS is not contained within the RHS and the
** RHS contains one or more NULL values.
**
** This routine generates code will jump to destIfFalse if the LHS is not 
** This routine generates code that jumps to destIfFalse if the LHS is not 
** contained within the RHS.  If due to NULLs we cannot determine if the LHS
** is contained in the RHS then jump to destIfNull.  If the LHS is contained
** within the RHS then fall through.
*/
static void sqlite3ExprCodeIN(
  Parse *pParse,        /* Parsing and code generating context */
  Expr *pExpr,          /* The IN expression */

  /* Compute the RHS.   After this step, the table with cursor
  ** pExpr->iTable will contains the values that make up the RHS.
  */
  v = pParse->pVdbe;
  assert( v!=0 );       /* OOM detected prior to this routine */
  VdbeNoopComment((v, "begin IN expr"));
  eType = sqlite3FindInIndex(pParse, pExpr, &rRhsHasNull);
  eType = sqlite3FindInIndex(pParse, pExpr,
                             IN_INDEX_MEMBERSHIP | IN_INDEX_NOOP_OK,
                             destIfFalse==destIfNull ? 0 : &rRhsHasNull);

  /* Figure out the affinity to use to create a key from the results
  ** of the expression. affinityStr stores a static string suitable for
  ** P4 of OP_MakeRecord.
  */
  affinity = comparisonAffinity(pExpr);

  /* Code the LHS, the <expr> from "<expr> IN (...)".
  */
  sqlite3ExprCachePush(pParse);
  r1 = sqlite3GetTempReg(pParse);
  sqlite3ExprCode(pParse, pExpr->pLeft, r1);

  /* If sqlite3FindInIndex() did not find or create an index that is
  ** suitable for evaluating the IN operator, then evaluate using a
  ** sequence of comparisons.
  */
  if( eType==IN_INDEX_NOOP ){
    ExprList *pList = pExpr->x.pList;
    CollSeq *pColl = sqlite3ExprCollSeq(pParse, pExpr->pLeft);
    int labelOk = sqlite3VdbeMakeLabel(v);
    int r2, regToFree;
    int regCkNull = 0;
    int ii;
    assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
    if( destIfNull!=destIfFalse ){
      regCkNull = sqlite3GetTempReg(pParse);
      sqlite3VdbeAddOp3(v, OP_BitAnd, r1, r1, regCkNull);
    }
    for(ii=0; ii<pList->nExpr; ii++){
      r2 = sqlite3ExprCodeTemp(pParse, pList->a[ii].pExpr, &regToFree);
      if( regCkNull && sqlite3ExprCanBeNull(pList->a[ii].pExpr) ){
        sqlite3VdbeAddOp3(v, OP_BitAnd, regCkNull, r2, regCkNull);
      }
      if( ii<pList->nExpr-1 || destIfNull!=destIfFalse ){
        sqlite3VdbeAddOp4(v, OP_Eq, r1, labelOk, r2,
                          (void*)pColl, P4_COLLSEQ);
        VdbeCoverageIf(v, ii<pList->nExpr-1);
        VdbeCoverageIf(v, ii==pList->nExpr-1);
        sqlite3VdbeChangeP5(v, affinity);
      }else{
        assert( destIfNull==destIfFalse );
        sqlite3VdbeAddOp4(v, OP_Ne, r1, destIfFalse, r2,
                          (void*)pColl, P4_COLLSEQ); VdbeCoverage(v);
        sqlite3VdbeChangeP5(v, affinity | SQLITE_JUMPIFNULL);
      }
      sqlite3ReleaseTempReg(pParse, regToFree);
    }
    if( regCkNull ){
      sqlite3VdbeAddOp2(v, OP_IsNull, regCkNull, destIfNull); VdbeCoverage(v);
      sqlite3VdbeAddOp2(v, OP_Goto, 0, destIfFalse);
    }
    sqlite3VdbeResolveLabel(v, labelOk);
    sqlite3ReleaseTempReg(pParse, regCkNull);
  }else{
  
  /* If the LHS is NULL, then the result is either false or NULL depending
  ** on whether the RHS is empty or not, respectively.
  */
  if( destIfNull==destIfFalse ){
    /* Shortcut for the common case where the false and NULL outcomes are
    ** the same. */
    sqlite3VdbeAddOp2(v, OP_IsNull, r1, destIfNull); VdbeCoverage(v);
  }else{
    int addr1 = sqlite3VdbeAddOp1(v, OP_NotNull, r1); VdbeCoverage(v);
    sqlite3VdbeAddOp2(v, OP_Rewind, pExpr->iTable, destIfFalse);
    VdbeCoverage(v);
    sqlite3VdbeAddOp2(v, OP_Goto, 0, destIfNull);
    sqlite3VdbeJumpHere(v, addr1);
  }

  if( eType==IN_INDEX_ROWID ){
    /* In this case, the RHS is the ROWID of table b-tree
    */
    sqlite3VdbeAddOp2(v, OP_MustBeInt, r1, destIfFalse); VdbeCoverage(v);
    sqlite3VdbeAddOp3(v, OP_NotExists, pExpr->iTable, destIfFalse, r1);
    VdbeCoverage(v);
  }else{
    /* In this case, the RHS is an index b-tree.
    */
    sqlite3VdbeAddOp4(v, OP_Affinity, r1, 1, 0, &affinity, 1);

    /* If the set membership test fails, then the result of the 
    ** "x IN (...)" expression must be either 0 or NULL. If the set
    ** contains no NULL values, then the result is 0. If the set 
    ** contains one or more NULL values, then the result of the
    ** expression is also NULL.
    */
    if( rRhsHasNull==0 || destIfFalse==destIfNull ){
      /* This branch runs if it is known at compile time that the RHS
      ** cannot contain NULL values. This happens as the result
      ** of a "NOT NULL" constraint in the database schema.
      **
      ** Also run this branch if NULL is equivalent to FALSE
      ** for this particular IN operator.
      */
      sqlite3VdbeAddOp4Int(v, OP_NotFound, pExpr->iTable, destIfFalse, r1, 1);
      VdbeCoverage(v);
    }else{
      /* In this branch, the RHS of the IN might contain a NULL and
      ** the presence of a NULL on the RHS makes a difference in the
      ** outcome.
      */
      int j1, j2;

      /* First check to see if the LHS is contained in the RHS.  If so,
      ** then the presence of NULLs in the RHS does not matter, so jump
      ** over all of the code that follows.
      */
      j1 = sqlite3VdbeAddOp4Int(v, OP_Found, pExpr->iTable, 0, r1, 1);
      VdbeCoverage(v);
    /* If the LHS is NULL, then the result is either false or NULL depending
    ** on whether the RHS is empty or not, respectively.
    */
    if( sqlite3ExprCanBeNull(pExpr->pLeft) ){
      if( destIfNull==destIfFalse ){
        /* Shortcut for the common case where the false and NULL outcomes are
        ** the same. */
        sqlite3VdbeAddOp2(v, OP_IsNull, r1, destIfNull); VdbeCoverage(v);
      }else{
        int addr1 = sqlite3VdbeAddOp1(v, OP_NotNull, r1); VdbeCoverage(v);
        sqlite3VdbeAddOp2(v, OP_Rewind, pExpr->iTable, destIfFalse);
        VdbeCoverage(v);
        sqlite3VdbeAddOp2(v, OP_Goto, 0, destIfNull);
        sqlite3VdbeJumpHere(v, addr1);
      }
    }
  
    if( eType==IN_INDEX_ROWID ){
      /* In this case, the RHS is the ROWID of table b-tree
      */
      sqlite3VdbeAddOp2(v, OP_MustBeInt, r1, destIfFalse); VdbeCoverage(v);
      sqlite3VdbeAddOp3(v, OP_NotExists, pExpr->iTable, destIfFalse, r1);
      VdbeCoverage(v);
    }else{
      /* In this case, the RHS is an index b-tree.
      */
      sqlite3VdbeAddOp4(v, OP_Affinity, r1, 1, 0, &affinity, 1);
  
      /* If the set membership test fails, then the result of the 
      ** "x IN (...)" expression must be either 0 or NULL. If the set
      ** contains no NULL values, then the result is 0. If the set 
      ** contains one or more NULL values, then the result of the
      ** expression is also NULL.
      */
      assert( destIfFalse!=destIfNull || rRhsHasNull==0 );
      if( rRhsHasNull==0 ){
        /* This branch runs if it is known at compile time that the RHS
        ** cannot contain NULL values. This happens as the result
        ** of a "NOT NULL" constraint in the database schema.
        **
        ** Also run this branch if NULL is equivalent to FALSE
        ** for this particular IN operator.
        */
        sqlite3VdbeAddOp4Int(v, OP_NotFound, pExpr->iTable, destIfFalse, r1, 1);
        VdbeCoverage(v);
      }else{
        /* In this branch, the RHS of the IN might contain a NULL and
        ** the presence of a NULL on the RHS makes a difference in the
        ** outcome.
        */
        int j1;
  
        /* First check to see if the LHS is contained in the RHS.  If so,
        ** then the answer is TRUE the presence of NULLs in the RHS does
        ** not matter.  If the LHS is not contained in the RHS, then the
        ** answer is NULL if the RHS contains NULLs and the answer is
        ** FALSE if the RHS is NULL-free.
        */
        j1 = sqlite3VdbeAddOp4Int(v, OP_Found, pExpr->iTable, 0, r1, 1);
        VdbeCoverage(v);

      /* Here we begin generating code that runs if the LHS is not
      ** contained within the RHS.  Generate additional code that
      ** tests the RHS for NULLs.  If the RHS contains a NULL then
      ** jump to destIfNull.  If there are no NULLs in the RHS then
      ** jump to destIfFalse.
      */
      sqlite3VdbeAddOp2(v, OP_If, rRhsHasNull, destIfNull); VdbeCoverage(v);
        sqlite3VdbeAddOp2(v, OP_IsNull, rRhsHasNull, destIfNull);
      sqlite3VdbeAddOp2(v, OP_IfNot, rRhsHasNull, destIfFalse); VdbeCoverage(v);
      j2 = sqlite3VdbeAddOp4Int(v, OP_Found, pExpr->iTable, 0, rRhsHasNull, 1);
      VdbeCoverage(v);
        VdbeCoverage(v);
      sqlite3VdbeAddOp2(v, OP_Integer, 0, rRhsHasNull);
      sqlite3VdbeAddOp2(v, OP_Goto, 0, destIfFalse);
      sqlite3VdbeJumpHere(v, j2);
        sqlite3VdbeAddOp2(v, OP_Goto, 0, destIfFalse);
        sqlite3VdbeJumpHere(v, j1);
      sqlite3VdbeAddOp2(v, OP_Integer, 1, rRhsHasNull);
      sqlite3VdbeAddOp2(v, OP_Goto, 0, destIfNull);

      }
      /* The OP_Found at the top of this branch jumps here when true, 
      ** causing the overall IN expression evaluation to fall through.
      */
      sqlite3VdbeJumpHere(v, j1);
    }
  }
  sqlite3ReleaseTempReg(pParse, r1);
  sqlite3ExprCachePop(pParse);
  VdbeComment((v, "end IN expr"));
}
#endif /* SQLITE_OMIT_SUBQUERY */

      assert( TK_NOTNULL==OP_NotNull ); testcase( op==TK_NOTNULL );
      sqlite3VdbeAddOp2(v, OP_Integer, 1, target);
      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
      testcase( regFree1==0 );
      addr = sqlite3VdbeAddOp1(v, op, r1);
      VdbeCoverageIf(v, op==TK_ISNULL);
      VdbeCoverageIf(v, op==TK_NOTNULL);
      sqlite3VdbeAddOp2(v, OP_AddImm, target, -1);
      sqlite3VdbeAddOp2(v, OP_Integer, 0, target);
      sqlite3VdbeJumpHere(v, addr);
      break;
    }
    case TK_AGG_FUNCTION: {
      AggInfo *pInfo = pExpr->pAggInfo;
      if( pInfo==0 ){
        assert( !ExprHasProperty(pExpr, EP_IntValue) );

        pFarg = pExpr->x.pList;
      }
      nFarg = pFarg ? pFarg->nExpr : 0;
      assert( !ExprHasProperty(pExpr, EP_IntValue) );
      zId = pExpr->u.zToken;
      nId = sqlite3Strlen30(zId);
      pDef = sqlite3FindFunction(db, zId, nId, nFarg, enc, 0);
      if( pDef==0 ){
      if( pDef==0 || pDef->xFunc==0 ){
        sqlite3ErrorMsg(pParse, "unknown function: %.*s()", nId, zId);
        break;
      }

      /* Attempt a direct implementation of the built-in COALESCE() and
      ** IFNULL() functions.  This avoids unnecessary evalation of
      ** arguments past the first non-NULL argument.

    assert( nCol>1 );
    aiCol = (int *)sqlite3DbMallocRaw(pParse->db, nCol*sizeof(int));
    if( !aiCol ) return 1;
    *paiCol = aiCol;
  }

  for(pIdx=pParent->pIndex; pIdx; pIdx=pIdx->pNext){
    if( pIdx->nKeyCol==nCol && pIdx->onError!=OE_None ){ 
    if( pIdx->nKeyCol==nCol && IsUniqueIndex(pIdx) ){ 
      /* pIdx is a UNIQUE index (or a PRIMARY KEY) and has the right number
      ** 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 

     && ((pDestCol->zDflt==0)!=(pSrcCol->zDflt==0) 
         || (pDestCol->zDflt && strcmp(pDestCol->zDflt, pSrcCol->zDflt)!=0))
    ){
      return 0;    /* Default values must be the same for all columns */
    }
  }
  for(pDestIdx=pDest->pIndex; pDestIdx; pDestIdx=pDestIdx->pNext){
    if( pDestIdx->onError!=OE_None ){
    if( IsUniqueIndex(pDestIdx) ){
      destHasUniqueIdx = 1;
    }
    for(pSrcIdx=pSrc->pIndex; pSrcIdx; pSrcIdx=pSrcIdx->pNext){
      if( xferCompatibleIndex(pDestIdx, pSrcIdx) ) break;
    }
    if( pSrcIdx==0 ){
      return 0;    /* pDestIdx has no corresponding index in pSrc */

}

/*
** Retrieve a pointer to a static mutex or allocate a new dynamic one.
*/
sqlite3_mutex *sqlite3_mutex_alloc(int id){
#ifndef SQLITE_OMIT_AUTOINIT
  if( sqlite3_initialize() ) return 0;
  if( id<=SQLITE_MUTEX_RECURSIVE && sqlite3_initialize() ) return 0;
#endif
  return sqlite3GlobalConfig.mutex.xMutexAlloc(id);
}

sqlite3_mutex *sqlite3MutexAlloc(int id){
  if( !sqlite3GlobalConfig.bCoreMutex ){
    return 0;

/*
** The sqlite3_mutex_alloc() routine allocates a new
** mutex and returns a pointer to it.  If it returns NULL
** that means that a mutex could not be allocated. 
*/
static sqlite3_mutex *debugMutexAlloc(int id){
  static sqlite3_debug_mutex aStatic[6];
  static sqlite3_debug_mutex aStatic[SQLITE_MUTEX_STATIC_APP3 - 1];
  sqlite3_debug_mutex *pNew = 0;
  switch( id ){
    case SQLITE_MUTEX_FAST:
    case SQLITE_MUTEX_RECURSIVE: {
      pNew = sqlite3Malloc(sizeof(*pNew));
      if( pNew ){
        pNew->id = id;

** to sqlite3_mutex_alloc() is one of these integer constants:
**
** <ul>
** <li>  SQLITE_MUTEX_FAST
** <li>  SQLITE_MUTEX_RECURSIVE
** <li>  SQLITE_MUTEX_STATIC_MASTER
** <li>  SQLITE_MUTEX_STATIC_MEM
** <li>  SQLITE_MUTEX_STATIC_MEM2
** <li>  SQLITE_MUTEX_STATIC_OPEN
** <li>  SQLITE_MUTEX_STATIC_PRNG
** <li>  SQLITE_MUTEX_STATIC_LRU
** <li>  SQLITE_MUTEX_STATIC_PMEM
** <li>  SQLITE_MUTEX_STATIC_APP1
** <li>  SQLITE_MUTEX_STATIC_APP2
** <li>  SQLITE_MUTEX_STATIC_APP3
** </ul>
**
** The first two constants cause sqlite3_mutex_alloc() to create
** a new mutex.  The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
** The mutex implementation does not need to make a distinction
** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does

** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
** returns a different mutex on every call.  But for the static 
** mutex types, the same mutex is returned on every call that has
** the same type number.
*/
static sqlite3_mutex *pthreadMutexAlloc(int iType){
  static sqlite3_mutex staticMutexes[] = {
    SQLITE3_MUTEX_INITIALIZER,
    SQLITE3_MUTEX_INITIALIZER,
    SQLITE3_MUTEX_INITIALIZER,
    SQLITE3_MUTEX_INITIALIZER,
    SQLITE3_MUTEX_INITIALIZER,
    SQLITE3_MUTEX_INITIALIZER,
    SQLITE3_MUTEX_INITIALIZER,
    SQLITE3_MUTEX_INITIALIZER,
    SQLITE3_MUTEX_INITIALIZER
  };

  return winMutexNotheld2(p, tid);
}
#endif

/*
** Initialize and deinitialize the mutex subsystem.
*/
static sqlite3_mutex winMutex_staticMutexes[6] = {
static sqlite3_mutex winMutex_staticMutexes[] = {
  SQLITE3_MUTEX_INITIALIZER,
  SQLITE3_MUTEX_INITIALIZER,
  SQLITE3_MUTEX_INITIALIZER,
  SQLITE3_MUTEX_INITIALIZER,
  SQLITE3_MUTEX_INITIALIZER,
  SQLITE3_MUTEX_INITIALIZER,
  SQLITE3_MUTEX_INITIALIZER,
  SQLITE3_MUTEX_INITIALIZER,
  SQLITE3_MUTEX_INITIALIZER
};

static int winMutex_isInit = 0;
static int winMutex_isNt = -1; /* <0 means "need to query" */

/* As winMutexInit() and winMutexEnd() are called as part of the
** sqlite3_initialize() and sqlite3_shutdown() processing, the
** "interlocked" magic used in this section may not strictly
/* As the winMutexInit() and winMutexEnd() functions are called as part
** of the sqlite3_initialize() and sqlite3_shutdown() processing, the
** "interlocked" magic used here is probably not strictly necessary.
** necessary.
*/
static LONG winMutex_lock = 0;
static LONG volatile winMutex_lock = 0;

int sqlite3_win32_is_nt(void); /* os_win.c */
void sqlite3_win32_sleep(DWORD milliseconds); /* os_win.c */

static int winMutexInit(void){
  /* The first to increment to 1 does actual initialization */
  if( InterlockedCompareExchange(&winMutex_lock, 1, 0)==0 ){

** to sqlite3_mutex_alloc() is one of these integer constants:
**
** <ul>
** <li>  SQLITE_MUTEX_FAST
** <li>  SQLITE_MUTEX_RECURSIVE
** <li>  SQLITE_MUTEX_STATIC_MASTER
** <li>  SQLITE_MUTEX_STATIC_MEM
** <li>  SQLITE_MUTEX_STATIC_MEM2
** <li>  SQLITE_MUTEX_STATIC_OPEN
** <li>  SQLITE_MUTEX_STATIC_PRNG
** <li>  SQLITE_MUTEX_STATIC_LRU
** <li>  SQLITE_MUTEX_STATIC_PMEM
** <li>  SQLITE_MUTEX_STATIC_APP1
** <li>  SQLITE_MUTEX_STATIC_APP2
** <li>  SQLITE_MUTEX_STATIC_APP3
** </ul>
**
** The first two constants cause sqlite3_mutex_alloc() to create
** a new mutex.  The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
** The mutex implementation does not need to make a distinction
** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does

*/
static void winMutexFree(sqlite3_mutex *p){
  assert( p );
#ifdef SQLITE_DEBUG
  assert( p->nRef==0 && p->owner==0 );
  assert( p->id==SQLITE_MUTEX_FAST || p->id==SQLITE_MUTEX_RECURSIVE );
#endif
  assert( winMutex_isInit==1 );
  DeleteCriticalSection(&p->mutex);
  sqlite3_free(p);
}

/*
** The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
** to enter a mutex.  If another thread is already within the mutex,

#endif
#ifdef SQLITE_DEBUG
  assert( p );
  assert( p->id==SQLITE_MUTEX_RECURSIVE || winMutexNotheld2(p, tid) );
#else
  assert( p );
#endif
  assert( winMutex_isInit==1 );
  EnterCriticalSection(&p->mutex);
#ifdef SQLITE_DEBUG
  assert( p->nRef>0 || p->owner==0 );
  p->owner = tid;
  p->nRef++;
  if( p->trace ){
    OSTRACE(("ENTER-MUTEX tid=%lu, mutex=%p (%d), nRef=%d\n",

  ** The TryEnterCriticalSection() interface is only available on WinNT.
  ** And some windows compilers complain if you try to use it without
  ** first doing some #defines that prevent SQLite from building on Win98.
  ** For that reason, we will omit this optimization for now.  See
  ** ticket #2685.
  */
#if defined(_WIN32_WINNT) && _WIN32_WINNT >= 0x0400
  assert( winMutex_isInit==1 );
  assert( winMutex_isNt>=-1 && winMutex_isNt<=1 );
  if( winMutex_isNt<0 ){
    winMutex_isNt = sqlite3_win32_is_nt();
  }
  assert( winMutex_isNt==0 || winMutex_isNt==1 );
  if( sqlite3_win32_is_nt() && TryEnterCriticalSection(&p->mutex) ){
  if( winMutex_isNt && TryEnterCriticalSection(&p->mutex) ){
#ifdef SQLITE_DEBUG
    p->owner = tid;
    p->nRef++;
#endif
    rc = SQLITE_OK;
  }
#else

#ifdef SQLITE_DEBUG
  assert( p->nRef>0 );
  assert( p->owner==tid );
  p->nRef--;
  if( p->nRef==0 ) p->owner = 0;
  assert( p->nRef==0 || p->id==SQLITE_MUTEX_RECURSIVE );
#endif
  assert( winMutex_isInit==1 );
  LeaveCriticalSection(&p->mutex);
#ifdef SQLITE_DEBUG
  if( p->trace ){
    OSTRACE(("LEAVE-MUTEX tid=%lu, mutex=%p (%d), nRef=%d\n",
             tid, p, p->trace, p->nRef));
  }
#endif

** 1:   Operating system is Win9x.
** 2:   Operating system is WinNT.
**
** In order to facilitate testing on a WinNT system, the test fixture
** can manually set this value to 1 to emulate Win98 behavior.
*/
#ifdef SQLITE_TEST
int sqlite3_os_type = 0;
#elif !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && \
LONG volatile sqlite3_os_type = 0;
#else
      defined(SQLITE_WIN32_HAS_ANSI) && defined(SQLITE_WIN32_HAS_WIDE)
static int sqlite3_os_type = 0;
static LONG volatile sqlite3_os_type = 0;
#endif

#ifndef SYSCALL
#  define SYSCALL sqlite3_syscall_ptr
#endif

/*

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

#define osCreateFileMappingFromApp ((HANDLE(WINAPI*)(HANDLE, \
        LPSECURITY_ATTRIBUTES,ULONG,ULONG64,LPCWSTR))aSyscall[75].pCurrent)

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

#define osInterlockedCompareExchange ((LONG(WINAPI*)(LONG volatile*, \
        LONG,LONG))aSyscall[76].pCurrent)

}; /* End of the overrideable system calls */

/*
** This is the xSetSystemCall() method of sqlite3_vfs for all of the
** "win32" VFSes.  Return SQLITE_OK opon successfully updating the
** system call pointer, or SQLITE_NOTFOUND if there is no configurable

#if !defined(SQLITE_WIN32_GETVERSIONEX) || !SQLITE_WIN32_GETVERSIONEX
# define osIsNT()  (1)
#elif SQLITE_OS_WINCE || SQLITE_OS_WINRT || !defined(SQLITE_WIN32_HAS_ANSI)
# define osIsNT()  (1)
#elif !defined(SQLITE_WIN32_HAS_WIDE)
# define osIsNT()  (0)
#else
# define osIsNT()  (sqlite3_win32_is_nt())
# define osIsNT()  ((sqlite3_os_type==2) || sqlite3_win32_is_nt())
#endif

/*
** This function determines if the machine is running a version of Windows
** based on the NT kernel.
*/
int sqlite3_win32_is_nt(void){
  if( sqlite3_os_type==0 ){
  if( osInterlockedCompareExchange(&sqlite3_os_type, 0, 0)==0 ){
#if defined(NTDDI_VERSION) && NTDDI_VERSION >= NTDDI_WIN8
    OSVERSIONINFOW sInfo;
    sInfo.dwOSVersionInfoSize = sizeof(sInfo);
    osGetVersionExW(&sInfo);
#else
    OSVERSIONINFOA sInfo;
    sInfo.dwOSVersionInfoSize = sizeof(sInfo);
    osGetVersionExA(&sInfo);
#endif
    osInterlockedCompareExchange(&sqlite3_os_type,
    sqlite3_os_type = (sInfo.dwPlatformId == VER_PLATFORM_WIN32_NT) ? 2 : 1;
        (sInfo.dwPlatformId == VER_PLATFORM_WIN32_NT) ? 2 : 1, 0);
  }
  return (sqlite3_os_type == 2);
  return osInterlockedCompareExchange(&sqlite3_os_type, 2, 2)==2;
}

#ifdef SQLITE_WIN32_MALLOC
/*
** Allocate nBytes of memory.
*/
static void *winMemMalloc(int nBytes){

    winGetSystemCall,    /* xGetSystemCall */
    winNextSystemCall,   /* xNextSystemCall */
  };
#endif

  /* Double-check that the aSyscall[] array has been constructed
  ** correctly.  See ticket [bb3a86e890c8e96ab] */
  assert( ArraySize(aSyscall)==76 );
  assert( ArraySize(aSyscall)==77 );

  /* get memory map allocation granularity */
  memset(&winSysInfo, 0, sizeof(SYSTEM_INFO));
#if SQLITE_OS_WINRT
  osGetNativeSystemInfo(&winSysInfo);
#else
  osGetSystemInfo(&winSysInfo);

      sqlite3CodeVerifySchema(pParse, iDb);
      sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seq", SQLITE_STATIC);
      sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", SQLITE_STATIC);
      sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "unique", SQLITE_STATIC);
      for(pIdx=pTab->pIndex, i=0; pIdx; pIdx=pIdx->pNext, i++){
        sqlite3VdbeAddOp2(v, OP_Integer, i, 1);
        sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, pIdx->zName, 0);
        sqlite3VdbeAddOp2(v, OP_Integer, pIdx->onError!=OE_None, 3);
        sqlite3VdbeAddOp2(v, OP_Integer, IsUniqueIndex(pIdx), 3);
        sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 3);
      }
    }
  }
  break;

  case PragTyp_DATABASE_LIST: {

    /* Code that appears at the end of the integrity check.  If no error
    ** messages have been generated, output OK.  Otherwise output the
    ** error message
    */
    static const int iLn = VDBE_OFFSET_LINENO(2);
    static const VdbeOpList endCode[] = {
      { OP_AddImm,      1, 0,        0},    /* 0 */
      { OP_IfNeg,       1, 0,        0},    /* 1 */
      { OP_String8,     0, 3,        0},    /* 2 */
      { OP_IfNeg,       1, 0,        0},    /* 0 */
      { OP_String8,     0, 3,        0},    /* 1 */
      { OP_ResultRow,   3, 1,        0},
    };

    int isQuick = (sqlite3Tolower(zLeft[0])=='q');

    /* If the PRAGMA command was of the form "PRAGMA <db>.integrity_check",
    ** then iDb is set to the index of the database identified by <db>.

        sqlite3VdbeAddOp2(v, OP_Integer, 0, 7);
        for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
          sqlite3VdbeAddOp2(v, OP_Integer, 0, 8+j); /* index entries counter */
        }
        pParse->nMem = MAX(pParse->nMem, 8+j);
        sqlite3VdbeAddOp2(v, OP_Rewind, iDataCur, 0); VdbeCoverage(v);
        loopTop = sqlite3VdbeAddOp2(v, OP_AddImm, 7, 1);
        /* Verify that all NOT NULL columns really are NOT NULL */
        for(j=0; j<pTab->nCol; j++){
          char *zErr;
          int jmp2, jmp3;
          if( j==pTab->iPKey ) continue;
          if( pTab->aCol[j].notNull==0 ) continue;
          sqlite3ExprCodeGetColumnOfTable(v, pTab, iDataCur, j, 3);
          sqlite3VdbeChangeP5(v, OPFLAG_TYPEOFARG);
          jmp2 = sqlite3VdbeAddOp1(v, OP_NotNull, 3); VdbeCoverage(v);
          sqlite3VdbeAddOp2(v, OP_AddImm, 1, -1); /* Decrement error limit */
          zErr = sqlite3MPrintf(db, "NULL value in %s.%s", pTab->zName,
                              pTab->aCol[j].zName);
          sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0, zErr, P4_DYNAMIC);
          sqlite3VdbeAddOp2(v, OP_ResultRow, 3, 1);
          jmp3 = sqlite3VdbeAddOp1(v, OP_IfPos, 1); VdbeCoverage(v);
          sqlite3VdbeAddOp0(v, OP_Halt);
          sqlite3VdbeJumpHere(v, jmp2);
          sqlite3VdbeJumpHere(v, jmp3);
        }
        /* Validate index entries for the current row */
        for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
          int jmp2, jmp3, jmp4;
          int jmp2, jmp3, jmp4, jmp5;
          int ckUniq = sqlite3VdbeMakeLabel(v);
          if( pPk==pIdx ) continue;
          r1 = sqlite3GenerateIndexKey(pParse, pIdx, iDataCur, 0, 0, &jmp3,
                                       pPrior, r1);
          pPrior = pIdx;
          sqlite3VdbeAddOp2(v, OP_AddImm, 8+j, 1);  /* increment entry count */
          /* Verify that an index entry exists for the current table row */
          jmp2 = sqlite3VdbeAddOp4Int(v, OP_Found, iIdxCur+j, 0, r1,
          jmp2 = sqlite3VdbeAddOp4Int(v, OP_Found, iIdxCur+j, ckUniq, r1,
                                      pIdx->nColumn); VdbeCoverage(v);
          sqlite3VdbeAddOp2(v, OP_AddImm, 1, -1); /* Decrement error limit */
          sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0, "row ", P4_STATIC);
          sqlite3VdbeAddOp3(v, OP_Concat, 7, 3, 3);
          sqlite3VdbeAddOp4(v, OP_String8, 0, 4, 0, " missing from index ",
                            P4_STATIC);
          sqlite3VdbeAddOp4(v, OP_String8, 0, 4, 0, 
                            " missing from index ", P4_STATIC);
          sqlite3VdbeAddOp3(v, OP_Concat, 4, 3, 3);
          sqlite3VdbeAddOp4(v, OP_String8, 0, 4, 0, pIdx->zName, P4_TRANSIENT);
          jmp5 = sqlite3VdbeAddOp4(v, OP_String8, 0, 4, 0,
                                   pIdx->zName, P4_TRANSIENT);
          sqlite3VdbeAddOp3(v, OP_Concat, 4, 3, 3);
          sqlite3VdbeAddOp2(v, OP_ResultRow, 3, 1);
          jmp4 = sqlite3VdbeAddOp1(v, OP_IfPos, 1); VdbeCoverage(v);
          sqlite3VdbeAddOp0(v, OP_Halt);
          sqlite3VdbeJumpHere(v, jmp4);
          sqlite3VdbeJumpHere(v, jmp2);
          sqlite3VdbeJumpHere(v, jmp2);
          /* For UNIQUE indexes, verify that only one entry exists with the
          ** current key.  The entry is unique if (1) any column is NULL
          ** or (2) the next entry has a different key */
          if( IsUniqueIndex(pIdx) ){
            int uniqOk = sqlite3VdbeMakeLabel(v);
            int jmp6;
            int kk;
            for(kk=0; kk<pIdx->nKeyCol; kk++){
              int iCol = pIdx->aiColumn[kk];
              assert( iCol>=0 && iCol<pTab->nCol );
              if( pTab->aCol[iCol].notNull ) continue;
              sqlite3VdbeAddOp2(v, OP_IsNull, r1+kk, uniqOk);
              VdbeCoverage(v);
            }
            jmp6 = sqlite3VdbeAddOp1(v, OP_Next, iIdxCur+j); VdbeCoverage(v);
            sqlite3VdbeAddOp2(v, OP_Goto, 0, uniqOk);
            sqlite3VdbeJumpHere(v, jmp6);
            sqlite3VdbeAddOp4Int(v, OP_IdxGT, iIdxCur+j, uniqOk, r1,
                                 pIdx->nKeyCol); VdbeCoverage(v);
            sqlite3VdbeAddOp2(v, OP_AddImm, 1, -1); /* Decrement error limit */
            sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0,
                              "non-unique entry in index ", P4_STATIC);
            sqlite3VdbeAddOp2(v, OP_Goto, 0, jmp5);
            sqlite3VdbeResolveLabel(v, uniqOk);
          }
          sqlite3VdbeJumpHere(v, jmp4);
          sqlite3ResolvePartIdxLabel(pParse, jmp3);
        }
        sqlite3VdbeAddOp2(v, OP_Next, iDataCur, loopTop); VdbeCoverage(v);
        sqlite3VdbeJumpHere(v, loopTop-1);
#ifndef SQLITE_OMIT_BTREECOUNT
        sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, 
                     "wrong # of entries in index ", P4_STATIC);

          sqlite3VdbeAddOp3(v, OP_Concat, 3, 2, 7);
          sqlite3VdbeAddOp2(v, OP_ResultRow, 7, 1);
        }
#endif /* SQLITE_OMIT_BTREECOUNT */
      } 
    }
    addr = sqlite3VdbeAddOpList(v, ArraySize(endCode), endCode, iLn);
    sqlite3VdbeChangeP2(v, addr, -mxErr);
    sqlite3VdbeJumpHere(v, addr+1);
    sqlite3VdbeChangeP4(v, addr+2, "ok", P4_STATIC);
    sqlite3VdbeChangeP3(v, addr, -mxErr);
    sqlite3VdbeJumpHere(v, addr);
    sqlite3VdbeChangeP4(v, addr+1, "ok", P4_STATIC);
  }
  break;
#endif /* SQLITE_OMIT_INTEGRITY_CHECK */

#ifndef SQLITE_OMIT_UTF16
  /*
  **   PRAGMA encoding

static void codeOffset(
  Vdbe *v,          /* Generate code into this VM */
  int iOffset,      /* Register holding the offset counter */
  int iContinue     /* Jump here to skip the current record */
){
  if( iOffset>0 ){
    int addr;
    sqlite3VdbeAddOp2(v, OP_AddImm, iOffset, -1);
    addr = sqlite3VdbeAddOp1(v, OP_IfNeg, iOffset); VdbeCoverage(v);
    addr = sqlite3VdbeAddOp3(v, OP_IfNeg, iOffset, 0, -1); VdbeCoverage(v);
    sqlite3VdbeAddOp2(v, OP_Goto, 0, iContinue);
    VdbeComment((v, "skip OFFSET records"));
    sqlite3VdbeJumpHere(v, addr);
  }
}

/*

** to sqlite3_mutex_alloc() is one of these integer constants:
**
** <ul>
** <li>  SQLITE_MUTEX_FAST
** <li>  SQLITE_MUTEX_RECURSIVE
** <li>  SQLITE_MUTEX_STATIC_MASTER
** <li>  SQLITE_MUTEX_STATIC_MEM
** <li>  SQLITE_MUTEX_STATIC_MEM2
** <li>  SQLITE_MUTEX_STATIC_OPEN
** <li>  SQLITE_MUTEX_STATIC_PRNG
** <li>  SQLITE_MUTEX_STATIC_LRU
** <li>  SQLITE_MUTEX_STATIC_LRU2
** <li>  SQLITE_MUTEX_STATIC_PMEM
** <li>  SQLITE_MUTEX_STATIC_APP1
** <li>  SQLITE_MUTEX_STATIC_APP2
** </ul>)^
**
** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE)
** cause sqlite3_mutex_alloc() to create
** a new mutex.  ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
** The mutex implementation does not need to make a distinction

#define SQLITE_MUTEX_STATIC_MEM       3  /* sqlite3_malloc() */
#define SQLITE_MUTEX_STATIC_MEM2      4  /* NOT USED */
#define SQLITE_MUTEX_STATIC_OPEN      4  /* sqlite3BtreeOpen() */
#define SQLITE_MUTEX_STATIC_PRNG      5  /* sqlite3_random() */
#define SQLITE_MUTEX_STATIC_LRU       6  /* lru page list */
#define SQLITE_MUTEX_STATIC_LRU2      7  /* NOT USED */
#define SQLITE_MUTEX_STATIC_PMEM      7  /* sqlite3PageMalloc() */
#define SQLITE_MUTEX_STATIC_APP1      8  /* For use by application */
#define SQLITE_MUTEX_STATIC_APP2      9  /* For use by application */
#define SQLITE_MUTEX_STATIC_APP3     10  /* For use by application */

/*
** CAPI3REF: Retrieve the mutex for a database connection
**
** ^This interface returns a pointer the [sqlite3_mutex] object that 
** serializes access to the [database connection] given in the argument
** when the [threading mode] is Serialized.

  Hash tblHash;        /* All tables indexed by name */
  Hash idxHash;        /* All (named) indices indexed by name */
  Hash trigHash;       /* All triggers indexed by name */
  Hash fkeyHash;       /* All foreign keys by referenced table name */
  Table *pSeqTab;      /* The sqlite_sequence table used by AUTOINCREMENT */
  u8 file_format;      /* Schema format version for this file */
  u8 enc;              /* Text encoding used by this database */
  u16 flags;           /* Flags associated with this schema */
  u16 schemaFlags;     /* Flags associated with this schema */
  int cache_size;      /* Number of pages to use in the cache */
};

/*
** These macros can be used to test, set, or clear bits in the 
** Db.pSchema->flags field.
*/
#define DbHasProperty(D,I,P)     (((D)->aDb[I].pSchema->flags&(P))==(P))
#define DbHasAnyProperty(D,I,P)  (((D)->aDb[I].pSchema->flags&(P))!=0)
#define DbSetProperty(D,I,P)     (D)->aDb[I].pSchema->flags|=(P)
#define DbClearProperty(D,I,P)   (D)->aDb[I].pSchema->flags&=~(P)
#define DbHasProperty(D,I,P)     (((D)->aDb[I].pSchema->schemaFlags&(P))==(P))
#define DbHasAnyProperty(D,I,P)  (((D)->aDb[I].pSchema->schemaFlags&(P))!=0)
#define DbSetProperty(D,I,P)     (D)->aDb[I].pSchema->schemaFlags|=(P)
#define DbClearProperty(D,I,P)   (D)->aDb[I].pSchema->schemaFlags&=~(P)

/*
** Allowed values for the DB.pSchema->flags field.
**
** The DB_SchemaLoaded flag is set after the database schema has been
** read into internal hash tables.
**

#define SQLITE_IDXTYPE_APPDEF      0   /* Created using CREATE INDEX */
#define SQLITE_IDXTYPE_UNIQUE      1   /* Implements a UNIQUE constraint */
#define SQLITE_IDXTYPE_PRIMARYKEY  2   /* Is the PRIMARY KEY for the table */

/* Return true if index X is a PRIMARY KEY index */
#define IsPrimaryKeyIndex(X)  ((X)->idxType==SQLITE_IDXTYPE_PRIMARYKEY)

/* Return true if index X is a UNIQUE index */
#define IsUniqueIndex(X)      ((X)->onError!=OE_None)

/*
** 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 {
  void *p;          /* Pointer to sampled record */

  void sqlite3BeginBenignMalloc(void);
  void sqlite3EndBenignMalloc(void);
#else
  #define sqlite3BeginBenignMalloc()
  #define sqlite3EndBenignMalloc()
#endif

/*
** Allowed return values from sqlite3FindInIndex()
*/
#define IN_INDEX_ROWID           1
#define IN_INDEX_EPH             2
#define IN_INDEX_INDEX_ASC       3
#define IN_INDEX_INDEX_DESC      4
int sqlite3FindInIndex(Parse *, Expr *, int*);
#define IN_INDEX_ROWID        1   /* Search the rowid of the table */
#define IN_INDEX_EPH          2   /* Search an ephemeral b-tree */
#define IN_INDEX_INDEX_ASC    3   /* Existing index ASCENDING */
#define IN_INDEX_INDEX_DESC   4   /* Existing index DESCENDING */
#define IN_INDEX_NOOP         5   /* No table available. Use comparisons */
/*
** Allowed flags for the 3rd parameter to sqlite3FindInIndex().
*/
#define IN_INDEX_NOOP_OK     0x0001  /* OK to return IN_INDEX_NOOP */
#define IN_INDEX_MEMBERSHIP  0x0002  /* IN operator used for membership test */
#define IN_INDEX_LOOP        0x0004  /* IN operator used as a loop */
int sqlite3FindInIndex(Parse *, Expr *, u32, int*);

#ifdef SQLITE_ENABLE_ATOMIC_WRITE
  int sqlite3JournalOpen(sqlite3_vfs *, const char *, sqlite3_file *, int, int);
  int sqlite3JournalSize(sqlite3_vfs *);
  int sqlite3JournalCreate(sqlite3_file *);
  int sqlite3JournalExists(sqlite3_file *p);
#else

  extern int sqlite3_opentemp_count;
  extern int sqlite3_like_count;
  extern int sqlite3_xferopt_count;
  extern int sqlite3_pager_readdb_count;
  extern int sqlite3_pager_writedb_count;
  extern int sqlite3_pager_writej_count;
#if SQLITE_OS_WIN
  extern int sqlite3_os_type;
  extern LONG volatile sqlite3_os_type;
#endif
#ifdef SQLITE_DEBUG
  extern int sqlite3WhereTrace;
  extern int sqlite3OSTrace;
  extern int sqlite3WalTrace;
#endif
#ifdef SQLITE_TEST

#endif
#ifndef SQLITE_OMIT_UTF16
  Tcl_LinkVar(interp, "sqlite_last_needed_collation",
      (char*)&pzNeededCollation, TCL_LINK_STRING|TCL_LINK_READ_ONLY);
#endif
#if SQLITE_OS_WIN
  Tcl_LinkVar(interp, "sqlite_os_type",
      (char*)&sqlite3_os_type, TCL_LINK_INT);
      (char*)&sqlite3_os_type, TCL_LINK_LONG);
#endif
#ifdef SQLITE_TEST
  {
    static const char *query_plan = "*** OBSOLETE VARIABLE ***";
    Tcl_LinkVar(interp, "sqlite_query_plan",
       (char*)&query_plan, TCL_LINK_STRING|TCL_LINK_READ_ONLY);
  }

**
** All SQLite database connections must be closed before calling this
** routine.
**
** THIS ROUTINE IS NOT THREADSAFE.  Call this routine exactly once while
** shutting down in order to free all remaining multiplex groups.
*/
int sqlite3_multiplex_shutdown(void){
int sqlite3_multiplex_shutdown(int eForce){
  int rc = SQLITE_OK;
  if( gMultiplex.isInitialized==0 ) return SQLITE_MISUSE;
  if( gMultiplex.pGroups ) return SQLITE_MISUSE;
  if( gMultiplex.pGroups ){
    sqlite3_log(SQLITE_MISUSE, "sqlite3_multiplex_shutdown() called "
                "while database connections are still open");
    if( !eForce ) return SQLITE_MISUSE;
    rc = SQLITE_MISUSE;
  }
  gMultiplex.isInitialized = 0;
  sqlite3_mutex_free(gMultiplex.pMutex);
  sqlite3_vfs_unregister(&gMultiplex.sThisVfs);
  memset(&gMultiplex, 0, sizeof(gMultiplex));
  return SQLITE_OK;
  return rc;
}

/***************************** Test Code ***********************************/
#ifdef SQLITE_TEST
#include <tcl.h>
extern const char *sqlite3ErrName(int);

  int objc,
  Tcl_Obj *CONST objv[]
){
  int rc;                         /* Value returned by multiplex_shutdown() */

  UNUSED_PARAMETER(clientData);

  if( objc==2 && strcmp(Tcl_GetString(objv[1]),"-force")!=0 ){
    objc = 3;
  }
  if( objc!=1 ){
    Tcl_WrongNumArgs(interp, 1, objv, "");
  if( (objc!=1 && objc!=2) ){
    Tcl_WrongNumArgs(interp, 1, objv, "?-force?");
    return TCL_ERROR;
  }

  /* Call sqlite3_multiplex_shutdown() */
  rc = sqlite3_multiplex_shutdown();
  rc = sqlite3_multiplex_shutdown(objc==2);
  Tcl_SetResult(interp, (char *)sqlite3ErrName(rc), TCL_STATIC);

  return TCL_OK;
}

/*
** tclcmd:  sqlite3_multiplex_dump

**
** All SQLite database connections must be closed before calling this
** routine.
**
** THIS ROUTINE IS NOT THREADSAFE.  Call this routine exactly once while
** shutting down in order to free all remaining multiplex groups.
*/
extern int sqlite3_multiplex_shutdown(void);
extern int sqlite3_multiplex_shutdown(int eForce);

#ifdef __cplusplus
}  /* End of the 'extern "C"' block */
#endif

#endif /* _TEST_MULTIPLEX_H */

    if( aToOpen[iDataCur-iBaseCur] ){
      assert( pPk!=0 );
      sqlite3VdbeAddOp4Int(v, OP_NotFound, iDataCur, labelBreak, regKey, nKey);
      VdbeCoverageNeverTaken(v);
    }
    labelContinue = labelBreak;
    sqlite3VdbeAddOp2(v, OP_IsNull, pPk ? regKey : regOldRowid, labelBreak);
    VdbeCoverage(v);
    VdbeCoverageIf(v, pPk==0);
    VdbeCoverageIf(v, pPk!=0);
  }else if( pPk ){
    labelContinue = sqlite3VdbeMakeLabel(v);
    sqlite3VdbeAddOp2(v, OP_Rewind, iEph, labelBreak); VdbeCoverage(v);
    addrTop = sqlite3VdbeAddOp2(v, OP_RowKey, iEph, regKey);
    sqlite3VdbeAddOp4Int(v, OP_NotFound, iDataCur, labelContinue, regKey, 0);
    VdbeCoverage(v);
  }else{

** feature is used for test suite validation only and does not appear an
** production builds.
**
** M is an integer, 2 or 3, that indices how many different ways the
** branch can go.  It is usually 2.  "I" is the direction the branch
** goes.  0 means falls through.  1 means branch is taken.  2 means the
** second alternative branch is taken.
**
** iSrcLine is the source code line (from the __LINE__ macro) that
** generated the VDBE instruction.  This instrumentation assumes that all
** source code is in a single file (the amalgamation).  Special values 1
** and 2 for the iSrcLine parameter mean that this particular branch is
** always taken or never taken, respectively.
*/
#if !defined(SQLITE_VDBE_COVERAGE)
# define VdbeBranchTaken(I,M)
#else
# define VdbeBranchTaken(I,M) vdbeTakeBranch(pOp->iSrcLine,I,M)
  static void vdbeTakeBranch(int iSrcLine, u8 I, u8 M){
    if( iSrcLine<=2 && ALWAYS(iSrcLine>0) ){

  pOut->flags = MEM_Int;
  if( pOp->p2 ) pc = pOp->p2 - 1;
  break;
}

/* Opcode:  EndCoroutine P1 * * * *
**
** The instruction at the address in register P1 is an Yield.
** The instruction at the address in register P1 is a Yield.
** Jump to the P2 parameter of that Yield.
** After the jump, register P1 becomes undefined.
**
** See also: InitCoroutine
*/
case OP_EndCoroutine: {           /* in1 */
  VdbeOp *pCaller;

}
#endif

/* Opcode: String8 * P2 * P4 *
** Synopsis: r[P2]='P4'
**
** P4 points to a nul terminated UTF-8 string. This opcode is transformed 
** into an OP_String before it is executed for the first time.  During
** into a String before it is executed for the first time.  During
** this transformation, the length of string P4 is computed and stored
** as the P1 parameter.
*/
case OP_String8: {         /* same as TK_STRING, out2-prerelease */
  assert( pOp->p4.z!=0 );
  pOp->opcode = OP_String;
  pOp->p1 = sqlite3Strlen30(pOp->p4.z);

  break;
}

/* Opcode: If P1 P2 P3 * *
**
** Jump to P2 if the value in register P1 is true.  The value
** is considered true if it is numeric and non-zero.  If the value
** in P1 is NULL then take the jump if P3 is non-zero.
** in P1 is NULL then take the jump if and only if P3 is non-zero.
*/
/* Opcode: IfNot P1 P2 P3 * *
**
** Jump to P2 if the value in register P1 is False.  The value
** is considered false if it has a numeric value of zero.  If the value
** in P1 is NULL then take the jump if P3 is zero.
** in P1 is NULL then take the jump if and only if P3 is non-zero.
*/
case OP_If:                 /* jump, in1 */
case OP_IfNot: {            /* jump, in1 */
  int c;
  pIn1 = &aMem[pOp->p1];
  if( pIn1->flags & MEM_Null ){
    c = pOp->p3;

** that are used as an unpacked index key. 
**
** Reposition cursor P1 so that  it points to the smallest entry that 
** is greater than or equal to the key value. If there are no records 
** greater than or equal to the key and P2 is not zero, then jump to P2.
**
** This opcode leaves the cursor configured to move in forward order,
** from the begining toward the end.  In other words, the cursor is
** from the beginning toward the end.  In other words, the cursor is
** configured to use Next, not Prev.
**
** See also: Found, NotFound, SeekLt, SeekGt, SeekLe
*/
/* Opcode: SeekGT P1 P2 P3 P4 *
** Synopsis: key=r[P3@P4]
**

** P4>0 then register P3 is the first of P4 registers that form an unpacked
** record.
**
** Cursor P1 is on an index btree.  If the record identified by P3 and P4
** is a prefix of any entry in P1 then a jump is made to P2 and
** P1 is left pointing at the matching entry.
**
** This operation leaves the cursor in a state where it cannot be
** advanced in either direction.  In other words, the Next and Prev
** opcodes do not work after this operation.
** This operation leaves the cursor in a state where it can be
** advanced in the forward direction.  The Next instruction will work,
** but not the Prev instruction.
**
** See also: NotFound, NoConflict, NotExists. SeekGe
*/
/* Opcode: NotFound P1 P2 P3 P4 *
** Synopsis: key=r[P3@P4]
**
** If P4==0 then register P3 holds a blob constructed by MakeRecord.  If

#endif

  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  assert( pOp->p4type==P4_INT32 );
  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );
#ifdef SQLITE_DEBUG
  pC->seekOp = 0;
  pC->seekOp = pOp->opcode;
#endif
  pIn3 = &aMem[pOp->p3];
  assert( pC->pCursor!=0 );
  assert( pC->isTable==0 );
  pFree = 0;  /* Not needed.  Only used to suppress a compiler warning. */
  if( pOp->p4.i>0 ){
    r.pKeyInfo = pC->pKeyInfo;

/* Opcode: Delete P1 P2 P3 P4 *
**
** Delete the record at which the P1 cursor is currently pointing.
**
** The cursor will be left pointing at either the next or the previous
** record in the table. If it is left pointing at the next record, then
** the next Next instruction will be a no-op.  Hence it is OK to delete
** a record from within an Next loop.
** a record from within a Next loop.
**
** If the OPFLAG_NCHANGE flag of P2 is set, then the row change count is
** incremented (otherwise not).
**
** P1 must not be pseudo-table.  It has to be a real table with
** multiple rows.
**

  break;
}

/* Opcode: SorterCompare P1 P2 P3 P4
** Synopsis:  if key(P1)!=trim(r[P3],P4) goto P2
**
** P1 is a sorter cursor. This instruction compares a prefix of the
** the record blob in register P3 against a prefix of the entry that 
** record blob in register P3 against a prefix of the entry that 
** the sorter cursor currently points to.  Only the first P4 fields
** of r[P3] and the sorter record are compared.
**
** If either P3 or the sorter contains a NULL in one of their significant
** fields (not counting the P4 fields at the end which are ignored) then
** the comparison is assumed to be equal.
**

  assert( pOp->opcode!=OP_NextIfOpen || pOp->p4.xAdvance==sqlite3BtreeNext );
  assert( pOp->opcode!=OP_PrevIfOpen || pOp->p4.xAdvance==sqlite3BtreePrevious);

  /* The Next opcode is only used after SeekGT, SeekGE, and Rewind.
  ** The Prev opcode is only used after SeekLT, SeekLE, and Last. */
  assert( pOp->opcode!=OP_Next || pOp->opcode!=OP_NextIfOpen
       || pC->seekOp==OP_SeekGT || pC->seekOp==OP_SeekGE
       || pC->seekOp==OP_Rewind );
       || pC->seekOp==OP_Rewind || pC->seekOp==OP_Found);
  assert( pOp->opcode!=OP_Prev || pOp->opcode!=OP_PrevIfOpen
       || pC->seekOp==OP_SeekLT || pC->seekOp==OP_SeekLE
       || pC->seekOp==OP_Last );

  rc = pOp->p4.xAdvance(pC->pCursor, &res);
next_tail:
  pC->cacheStatus = CACHE_STALE;

  VdbeBranchTaken( pIn1->u.i>0, 2);
  if( pIn1->u.i>0 ){
     pc = pOp->p2 - 1;
  }
  break;
}

/* Opcode: IfNeg P1 P2 * * *
** Synopsis: if r[P1]<0 goto P2
/* Opcode: IfNeg P1 P2 P3 * *
** Synopsis: r[P1]+=P3, if r[P1]<0 goto P2
**
** Register P1 must contain an integer.  Add literal P3 to the value in
** If the value of register P1 is less than zero, jump to P2. 
** register P1 then if the value of register P1 is less than zero, jump to P2. 
**
** It is illegal to use this instruction on a register that does
** not contain an integer.  An assertion fault will result if you try.
*/
case OP_IfNeg: {        /* jump, in1 */
  pIn1 = &aMem[pOp->p1];
  assert( pIn1->flags&MEM_Int );
  pIn1->u.i += pOp->p3;
  VdbeBranchTaken(pIn1->u.i<0, 2);
  if( pIn1->u.i<0 ){
     pc = pOp->p2 - 1;
  }
  break;
}

/* Opcode: IfZero P1 P2 P3 * *
** Synopsis: r[P1]+=P3, if r[P1]==0 goto P2
**
** The register P1 must contain an integer.  Add literal P3 to the
** value in register P1.  If the result is exactly 0, jump to P2. 
**
** It is illegal to use this instruction on a register that does
** not contain an integer.  An assertion fault will result if you try.
*/
case OP_IfZero: {        /* jump, in1 */
  pIn1 = &aMem[pOp->p1];
  assert( pIn1->flags&MEM_Int );
  pIn1->u.i += pOp->p3;
  VdbeBranchTaken(pIn1->u.i==0, 2);
  if( pIn1->u.i==0 ){

  **      where X is a constant value. The collation sequences of the
  **      comparison and select-list expressions must match those of the index.
  **
  **   3. All of those index columns for which the WHERE clause does not
  **      contain a "col=X" term are subject to a NOT NULL constraint.
  */
  for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
    if( pIdx->onError==OE_None ) continue;
    if( !IsUniqueIndex(pIdx) ) continue;
    for(i=0; i<pIdx->nKeyCol; i++){
      i16 iCol = pIdx->aiColumn[i];
      if( 0==findTerm(pWC, iBase, iCol, ~(Bitmask)0, WO_EQ, pIdx) ){
        int iIdxCol = findIndexCol(pParse, pDistinct, iBase, pIdx, i);
        if( iIdxCol<0 || pTab->aCol[iCol].notNull==0 ){
          break;
        }

    ){
      testcase( iEq==0 );
      testcase( bRev );
      bRev = !bRev;
    }
    assert( pX->op==TK_IN );
    iReg = iTarget;
    eType = sqlite3FindInIndex(pParse, pX, 0);
    eType = sqlite3FindInIndex(pParse, pX, IN_INDEX_LOOP, 0);
    if( eType==IN_INDEX_INDEX_DESC ){
      testcase( bRev );
      bRev = !bRev;
    }
    iTab = pX->iTable;
    sqlite3VdbeAddOp2(v, bRev ? OP_Last : OP_Rewind, iTab, 0);
    VdbeCoverageIf(v, bRev);

      }
      assert( nIn>0 );  /* RHS always has 2 or more terms...  The parser
                        ** changes "x IN (?)" into "x=?". */

    }else if( eOp & (WO_EQ) ){
      pNew->wsFlags |= WHERE_COLUMN_EQ;
      if( iCol<0 || (nInMul==0 && pNew->u.btree.nEq==pProbe->nKeyCol-1) ){
        if( iCol>=0 && pProbe->onError==OE_None ){
        if( iCol>=0 && !IsUniqueIndex(pProbe) ){
          pNew->wsFlags |= WHERE_UNQ_WANTED;
        }else{
          pNew->wsFlags |= WHERE_ONEROW;
        }
      }
    }else if( eOp & WO_ISNULL ){
      pNew->wsFlags |= WHERE_COLUMN_NULL;

      }else if( (pIndex = pLoop->u.btree.pIndex)==0 || pIndex->bUnordered ){
        return 0;
      }else{
        nKeyCol = pIndex->nKeyCol;
        nColumn = pIndex->nColumn;
        assert( nColumn==nKeyCol+1 || !HasRowid(pIndex->pTable) );
        assert( pIndex->aiColumn[nColumn-1]==(-1) || !HasRowid(pIndex->pTable));
        isOrderDistinct = pIndex->onError!=OE_None;
        isOrderDistinct = IsUniqueIndex(pIndex);
      }

      /* Loop through all columns of the index and deal with the ones
      ** that are not constrained by == or IN.
      */
      rev = revSet = 0;
      distinctColumns = 0;

    pLoop->u.btree.nEq = 1;
    /* TUNING: Cost of a rowid lookup is 10 */
    pLoop->rRun = 33;  /* 33==sqlite3LogEst(10) */
  }else{
    for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
      assert( pLoop->aLTermSpace==pLoop->aLTerm );
      assert( ArraySize(pLoop->aLTermSpace)==4 );
      if( pIdx->onError==OE_None 
      if( !IsUniqueIndex(pIdx)
       || pIdx->pPartIdxWhere!=0 
       || pIdx->nKeyCol>ArraySize(pLoop->aLTermSpace) 
      ) continue;
      for(j=0; j<pIdx->nKeyCol; j++){
        pTerm = findTerm(pWC, iCur, pIdx->aiColumn[j], 0, WO_EQ, pIdx);
        if( pTerm==0 ) break;
        pLoop->aLTerm[j] = pTerm;

  SELECT * FROM t3 WHERE x IN (10);
} {10 10 10}
do_execsql_test in4-3.44 {
  EXPLAIN
  SELECT * FROM t3 WHERE x IN (10);
} {~/OpenEphemeral/}
do_execsql_test in4-3.45 {
  SELECT * FROM t3 WHERE x NOT IN (10,11);
  SELECT * FROM t3 WHERE x NOT IN (10,11,99999);
} {1 1 1}
do_execsql_test in4-3.46 {
  EXPLAIN
  SELECT * FROM t3 WHERE x NOT IN (10,11);
  SELECT * FROM t3 WHERE x NOT IN (10,11,99999);
} {/OpenEphemeral/}
do_execsql_test in4-3.47 {
  SELECT * FROM t3 WHERE x NOT IN (10);
} {1 1 1}
do_execsql_test in4-3.48 {
  EXPLAIN
  SELECT * FROM t3 WHERE x NOT IN (10);

    forcedelete [multiplex_name $name $i]
    forcedelete [multiplex_name $name-journal $i]
    forcedelete [multiplex_name $name-wal $i]
  }
}

db close
sqlite3_shutdown
test_sqlite3_log xLog
proc xLog {error_code msg} {
  lappend ::log $error_code $msg 
}
unset -nocomplain log

multiplex_delete test.db
multiplex_delete test2.db

#-------------------------------------------------------------------------
#   multiplex-1.1.*: Test initialize and shutdown.

do_test multiplex-2.3.1 {
  sqlite3 db2 test2.x
  db2 close
} {}


unset -nocomplain ::log
do_test multiplex-2.4.1 {
  sqlite3_multiplex_shutdown
} {SQLITE_MISUSE}
do_test multiplex-2.4.2 {
  execsql { INSERT INTO t1 VALUES(3, randomblob(1100)) }
} {}
do_test multiplex-2.4.3 {
  set ::log
} {SQLITE_MISUSE {sqlite3_multiplex_shutdown() called while database connections are still open}}
do_test multiplex-2.4.4 { file size [multiplex_name test.x 0] } {7168}
do_test multiplex-2.4.5 {
  db close
  sqlite3 db test.x
  db eval vacuum
  db close
  glob test.x*

  multiplex_delete test.x
  sqlite3_multiplex_shutdown
} {SQLITE_OK}

}


catch { db close }
catch { sqlite3_multiplex_shutdown }
sqlite3_shutdown
test_sqlite3_log 
sqlite3_initialize
finish_test

  do_test pragma-3.19 {
    catch {db close}
    forcedelete test.db test.db-journal
    sqlite3 db test.db
    db eval {PRAGMA integrity_check}
  } {ok}
}
#exit

# Verify that PRAGMA integrity_check catches UNIQUE and NOT NULL
# constraint violations.
#
do_execsql_test pragma-3.20 {
  CREATE TABLE t1(a,b);
  CREATE INDEX t1a ON t1(a);
  INSERT INTO t1 VALUES(1,1),(2,2),(3,3),(2,4),(NULL,5),(NULL,6);
  PRAGMA writable_schema=ON;
  UPDATE sqlite_master SET sql='CREATE UNIQUE INDEX t1a ON t1(a)'
   WHERE name='t1a';
  UPDATE sqlite_master SET sql='CREATE TABLE t1(a NOT NULL,b)'
   WHERE name='t1';
  PRAGMA writable_schema=OFF;
  ALTER TABLE t1 RENAME TO t1x;
  PRAGMA integrity_check;
} {{non-unique entry in index t1a} {NULL value in t1x.a} {non-unique entry in index t1a} {NULL value in t1x.a}}
do_execsql_test pragma-3.21 {
  PRAGMA integrity_check(3);
} {{non-unique entry in index t1a} {NULL value in t1x.a} {non-unique entry in index t1a}}
do_execsql_test pragma-3.22 {
  PRAGMA integrity_check(2);
} {{non-unique entry in index t1a} {NULL value in t1x.a}}
do_execsql_test pragma-3.21 {
  PRAGMA integrity_check(1);
} {{non-unique entry in index t1a}}

# Test modifying the cache_size of an attached database.
ifcapable pager_pragmas&&attach {
do_test pragma-4.1 {
  execsql {
    ATTACH 'test2.db' AS aux;
    pragma aux.cache_size;

do_test table-15.2 {
  execsql {BEGIN}
  for {set i 0} {$i<2000} {incr i} {
    execsql "DROP TABLE tbl$i"
  }
  execsql {COMMIT}
} {}

# Ticket 3a88d85f36704eebe134f7f48aebf00cd6438c1a (2014-08-05)
# The following SQL script segfaults while running the INSERT statement:
#
#    CREATE TABLE t1(x DEFAULT(max(1)));
#    INSERT INTO t1(rowid) VALUES(1);
#
# The problem appears to be the use of an aggregate function as part of
# the default value for a column. This problem has been in the code since
# at least 2006-01-01 and probably before that. This problem was detected
# and reported on the sqlite-users@sqlite.org mailing list by Zsbán Ambrus. 
#
do_execsql_test table-16.1 {
  CREATE TABLE t16(x DEFAULT(max(1)));
  INSERT INTO t16(x) VALUES(123);
  SELECT rowid, x FROM t16;
} {1 123}
do_catchsql_test table-16.2 {
  INSERT INTO t16(rowid) VALUES(4);
} {1 {unknown function: max()}}
do_execsql_test table-16.3 {
  DROP TABLE t16;
  CREATE TABLE t16(x DEFAULT(abs(1)));
  INSERT INTO t16(rowid) VALUES(4);
  SELECT rowid, x FROM t16;
} {4 1}
do_catchsql_test table-16.4 {
  DROP TABLE t16;
  CREATE TABLE t16(x DEFAULT(avg(1)));
  INSERT INTO t16(rowid) VALUES(123);
  SELECT rowid, x FROM t16;
} {1 {unknown function: avg()}}
do_catchsql_test table-16.5 {
  DROP TABLE t16;
  CREATE TABLE t16(x DEFAULT(count()));
  INSERT INTO t16(rowid) VALUES(123);
  SELECT rowid, x FROM t16;
} {1 {unknown function: count()}}
do_catchsql_test table-16.6 {
  DROP TABLE t16;
  CREATE TABLE t16(x DEFAULT(group_concat('x',',')));
  INSERT INTO t16(rowid) VALUES(123);
  SELECT rowid, x FROM t16;
} {1 {unknown function: group_concat()}}
do_catchsql_test table-16.7 {
  INSERT INTO t16 DEFAULT VALUES;
} {1 {unknown function: group_concat()}}

finish_test

  }
}

# Run this routine last
#
proc finish_test {} {
  catch {db close}
  catch {db1 close}
  catch {db2 close}
  catch {db3 close}
  if {0==[info exists ::SLAVE]} { finalize_testing }
}
proc finalize_testing {} {
  global sqlite_open_file_count

do_execsql_test tkt-80e031a00f.319 {SELECT 'c' NOT IN t7} 0
do_execsql_test tkt-80e031a00f.320 {SELECT 'c' IN t7n} 1
do_execsql_test tkt-80e031a00f.321 {SELECT 'd' NOT IN t7n} 0
do_execsql_test tkt-80e031a00f.322 {SELECT 'b' IN t8} 1
do_execsql_test tkt-80e031a00f.323 {SELECT 'c' NOT IN t8} 0
do_execsql_test tkt-80e031a00f.324 {SELECT 'c' IN t8n} 1
do_execsql_test tkt-80e031a00f.325 {SELECT 'd' NOT IN t8n} 0
do_execsql_test tkt-80e031a00f.326 {SELECT 'a' IN (NULL,'a')} 1
do_execsql_test tkt-80e031a00f.327 {SELECT 'a' IN (NULL,'b')} {{}}
do_execsql_test tkt-80e031a00f.328 {SELECT 'a' NOT IN (NULL,'a')} 0
do_execsql_test tkt-80e031a00f.329 {SELECT 'a' NOT IN (NULL,'b')} {{}}
#
# Row 4:
do_execsql_test tkt-80e031a00f.400 {SELECT 1 IN (2,3,4,null)} {{}}
do_execsql_test tkt-80e031a00f.401 {SELECT 1 NOT IN (2,3,4,null)} {{}}
do_execsql_test tkt-80e031a00f.402 {SELECT 'a' IN ('b','c',null,'d')} {{}}
do_execsql_test tkt-80e031a00f.403 {SELECT 'a' NOT IN (null,'b','c','d')} {{}}
do_execsql_test tkt-80e031a00f.404 {SELECT 1 IN t4n} {{}}