Allow subqueries on the right-hand side of a LEFT JOIN to be flattened even

if they contain a GROUP BY clause.

FossilOrigin-Name: 816da9a893ae97a21463562479edb419a8b511ae731d86eccee3fa6e3e7dc96e

2 files changed, 23 insertions, 13 deletions

diff --git a/src/expr.c b/src/expr.c
index 876b453f1..c9c7c2e76 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -4670,12 +4670,20 @@ expr_code_doover:
     case TK_IF_NULL_ROW: {
       int addrINR;
       u8 okConstFactor = pParse->okConstFactor;
-      if( pExpr->pAggInfo && !pExpr->pAggInfo->directMode ){
-        struct AggInfo_col *pCol;
-        assert( pExpr->iAgg>=0 && pExpr->iAgg<pExpr->pAggInfo->nColumn );
-        pCol = &pExpr->pAggInfo->aCol[pExpr->iAgg];
-        inReg = pCol->iMem;
-        break;
+      AggInfo *pAggInfo = pExpr->pAggInfo;
+      if( pAggInfo ){
+        assert( pExpr->iAgg>=0 && pExpr->iAgg<pAggInfo->nColumn );
+        if( !pAggInfo->directMode ){
+          inReg = pAggInfo->aCol[pExpr->iAgg].iMem;
+          break;
+        }
+        if( pExpr->pAggInfo->useSortingIdx ){
+          sqlite3VdbeAddOp3(v, OP_Column, pAggInfo->sortingIdxPTab,
+                            pAggInfo->aCol[pExpr->iAgg].iSorterColumn,
+                            target);
+          inReg = target;
+          break;
+        }
       }
       addrINR = sqlite3VdbeAddOp1(v, OP_IfNullRow, pExpr->iTable);
       /* Temporarily disable factoring of constant expressions, since
@@ -6187,6 +6195,7 @@ static int analyzeAggregate(Walker *pWalker, Expr *pExpr){
     case TK_COLUMN: {
       testcase( pExpr->op==TK_AGG_COLUMN );
       testcase( pExpr->op==TK_COLUMN );
+      testcase( pExpr->op==TK_IF_NULL_ROW );
       /* Check to see if the column is in one of the tables in the FROM
       ** clause of the aggregate query */
       if( ALWAYS(pSrcList!=0) ){
@@ -6245,7 +6254,9 @@ static int analyzeAggregate(Walker *pWalker, Expr *pExpr){
             */
             ExprSetVVAProperty(pExpr, EP_NoReduce);
             pExpr->pAggInfo = pAggInfo;
-            if( pExpr->op==TK_COLUMN ) pExpr->op = TK_AGG_COLUMN;
+            if( pExpr->op==TK_COLUMN ){
+              pExpr->op = TK_AGG_COLUMN;
+            }
             pExpr->iAgg = (i16)k;
             break;
           } /* endif pExpr->iTable==pItem->iCursor */
diff --git a/src/select.c b/src/select.c
index 90ba47fa8..672461d44 100644
--- a/src/select.c
+++ b/src/select.c
@@ -4065,8 +4065,8 @@ static void renumberCursors(
 **        (3a) the subquery may not be a join and
 **        (3b) the FROM clause of the subquery may not contain a virtual
 **             table and
-**        (3c) The outer query may not have a GROUP BY.  (This limitation is
-**             due to how TK_IF_NULL_ROW works.  FIX ME!)
+**        (**) Was: "The outer query may not have a GROUP BY." This case
+**             is now managed correctly
 **        (3d) the outer query may not be DISTINCT.
 **        See also (26) for restrictions on RIGHT JOIN.
 **
@@ -4284,7 +4284,6 @@ static int flattenSubquery(
     if( pSubSrc->nSrc>1                        /* (3a) */
      || IsVirtual(pSubSrc->a[0].pTab)          /* (3b) */
      || (p->selFlags & SF_Distinct)!=0         /* (3d) */
-     || (p->pGroupBy!=0)                       /* (3c) */
      || (pSubitem->fg.jointype & JT_RIGHT)!=0  /* (26) */
     ){
       return 0;
@@ -7541,15 +7540,15 @@ int sqlite3Select(
         regBase = sqlite3GetTempRange(pParse, nCol);
         sqlite3ExprCodeExprList(pParse, pGroupBy, regBase, 0, 0);
         j = nGroupBy;
+        pAggInfo->directMode = 1;
         for(i=0; i<pAggInfo->nColumn; i++){
           struct AggInfo_col *pCol = &pAggInfo->aCol[i];
           if( pCol->iSorterColumn>=j ){
-            int r1 = j + regBase;
-            sqlite3ExprCodeGetColumnOfTable(v,
-                               pCol->pTab, pCol->iTable, pCol->iColumn, r1);
+            sqlite3ExprCode(pParse, pCol->pCExpr, j + regBase);
             j++;
           }
         }
+        pAggInfo->directMode = 0;
         regRecord = sqlite3GetTempReg(pParse);
         sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase, nCol, regRecord);
         sqlite3VdbeAddOp2(v, OP_SorterInsert, pAggInfo->sortingIdx, regRecord);