SQLite

        ** Generate code to write the results of the select into the temporary
        ** table allocated and opened above.
        */
        Select *pSelect = pExpr->x.pSelect;
        ExprList *pEList = pSelect->pEList;

        assert( !isRowid );
        /* If the LHS and RHS of the IN operator do not match, that
        ** error will have been caught long before we reach this point. */
        if( ALWAYS(pEList->nExpr==nVal) ){


          SelectDest dest;
          int i;
          sqlite3SelectDestInit(&dest, SRT_Set, pExpr->iTable);
          dest.zAffSdst = exprINAffinity(pParse, pExpr);
          assert( (pExpr->iTable&0x0000FFFF)==pExpr->iTable );
          pSelect->iLimit = 0;
          testcase( pSelect->selFlags & SF_Distinct );

**
**   CREATE INDEX ... ON (a, b, c, d, e)
**
** then this function would be invoked with nEq=1. The value returned in
** this case is 3.
*/
int whereRangeVectorLen(
  Parse *pParse,       /* Parsing context */
  int iCur,            /* Cursor open on pIdx */
  Index *pIdx,         /* The index to be used for a inequality constraint */
  int nEq,             /* Number of prior equality constraints on same index */
  WhereTerm *pTerm     /* The vector inequality constraint */
){
  int nCmp = sqlite3ExprVectorSize(pTerm->pExpr->pLeft);
  int i;

  nCmp = MIN(nCmp, (pIdx->nColumn - nEq));
  for(i=1; i<nCmp; i++){
    /* Test if comparison i of pTerm is compatible with column (i+nEq) 

    }

    aff = sqlite3CompareAffinity(pRhs, sqlite3ExprAffinity(pLhs));
    idxaff = pIdx->pTable->aCol[pLhs->iColumn].affinity;
    if( aff!=idxaff ) break;

    pColl = sqlite3BinaryCompareCollSeq(pParse, pLhs, pRhs);
    if( NEVER(pColl==0) ) break;
    if( sqlite3StrICmp(pColl->zName, pIdx->azColl[i+nEq]) ) break;
  }
  return i;
}

/*
** Adjust the cost C by the costMult facter T.  This only occurs if
** compiled with -DSQLITE_ENABLE_COSTMULT

          ** considered to match an ORDER BY term.  */
          if( (eOp & eqOpMask)!=0 ){
            if( eOp & WO_ISNULL ){
              testcase( isOrderDistinct );
              isOrderDistinct = 0;
            }
            continue;  
          }else if( ALWAYS(eOp & WO_IN) ){
            /* ALWAYS() justification: eOp is an equality operator due to the
            ** j<pLoop->u.btree.nEq constraint above.  Any equality other
            ** than WO_IN is captured by the previous "if".  So this one
            ** always has to be WO_IN. */
            Expr *pX = pLoop->aLTerm[j]->pExpr;
            for(i=j+1; i<pLoop->u.btree.nEq; i++){
              if( pLoop->aLTerm[i]->pExpr==pX ){
                assert( (pLoop->aLTerm[i]->eOperator & WO_IN) );
                bOnce = 0;
                break;
              }

  int i;
  int iCur;

  /* If this expression is a vector to the left or right of a 
  ** inequality constraint (>, <, >= or <=), perform the processing 
  ** on the first element of the vector.  */
  assert( TK_GT+1==TK_LE && TK_GT+2==TK_LT && TK_GT+3==TK_GE );
  assert( TK_IS<TK_GE && TK_ISNULL<TK_GE && TK_IN<TK_GE );
  assert( op<=TK_GE );
  if( pExpr->op==TK_VECTOR && (op>=TK_GT && ALWAYS(op<=TK_GE)) ){
    pExpr = pExpr->x.pList->a[0].pExpr;
  }

  if( pExpr->op==TK_COLUMN ){
    *piCur = pExpr->iTable;
    *piColumn = pExpr->iColumn;
    return 1;