Change the way TK_SELECT_COLUMN is handled so that the subquery is only

generated once even if part of the vector comparison is used for indexing
and the other part is now.  This change also is a pathway to vector assignment
in UPDATE statements.

FossilOrigin-Name: d8feea7dcde83179bff303072426561cfe825e58

1 files changed, 2 insertions, 33 deletions

diff --git a/src/wherecode.c b/src/wherecode.c
index dd15b5893..2ef9a46b5 100644
--- a/src/wherecode.c
+++ b/src/wherecode.c
@@ -377,34 +377,7 @@ static int codeEqualityTerm(
   assert( pLevel->pWLoop->aLTerm[iEq]==pTerm );
   assert( iTarget>0 );
   if( pX->op==TK_EQ || pX->op==TK_IS ){
-    Expr *pRight = pX->pRight;
-#ifndef SQLITE_OMIT_SUBQUERY
-    if( pRight->op==TK_SELECT_COLUMN ){
-      /* This case occurs for expressions like "(a, b) == (SELECT ...)". */
-      WhereLoop *pLoop = pLevel->pWLoop;
-      int i;
-      Expr *pSub = pRight->pLeft;
-      assert( pSub->op==TK_SELECT );
-      for(i=pLoop->nSkip; i<iEq; i++){
-        Expr *pExpr = pLoop->aLTerm[i]->pExpr->pRight;
-        if( pExpr && pExpr->op==TK_SELECT_COLUMN && pExpr->pLeft==pSub ) break;
-      }
-
-      if( i==iEq ){
-        iReg = sqlite3CodeSubselect(pParse, pSub, 0, 0);
-        for(/*no-op*/; i<pLoop->nLTerm; i++){
-          Expr *pExpr = pLoop->aLTerm[i]->pExpr->pRight;
-          if( pExpr && pExpr->op==TK_SELECT_COLUMN && pExpr->pLeft==pSub ){
-            sqlite3VdbeAddOp2(v, OP_Copy, iReg+pExpr->iColumn, iTarget-iEq+i);
-          }
-        }
-      }
-      iReg = iTarget;
-    }else
-#endif
-    {
-      iReg = sqlite3ExprCodeTarget(pParse, pRight, iTarget);
-    }
+    iReg = sqlite3ExprCodeTarget(pParse, pX->pRight, iTarget);
   }else if( pX->op==TK_ISNULL ){
     iReg = iTarget;
     sqlite3VdbeAddOp2(v, OP_Null, 0, iReg);
@@ -1101,11 +1074,7 @@ Bitmask sqlite3WhereCodeOneLoopStart(
         addrNotFound = pLevel->addrNxt;
       }else{
         Expr *pRight = pTerm->pExpr->pRight;
-        if( pRight->op==TK_SELECT_COLUMN ){
-          codeEqualityTerm(pParse, pTerm, pLevel, j, bRev, iTarget);
-        }else{
-          codeExprOrVector(pParse, pRight, iTarget, 1);
-        }
+        codeExprOrVector(pParse, pRight, iTarget, 1);
       }
     }
     sqlite3VdbeAddOp2(v, OP_Integer, pLoop->u.vtab.idxNum, iReg);