Further enhancements to the min/max optimization of

[/info/b8ba2f17f938c035|check-in b8ba2f17f938c035] to fix the performance
regression identified by
[forum:/forumpost/623f571482|forum post 623f571482].

FossilOrigin-Name: 188772a1dbaf066fbddd39c718fdd87478b19a920622f4640bcb79d4ef065331

3 files changed, 27 insertions, 5 deletions

diff --git a/src/select.c b/src/select.c
index f00a3acd8..76806b66e 100644
--- a/src/select.c
+++ b/src/select.c
@@ -6773,7 +6773,7 @@ int sqlite3Select(
       /* End of the loop
       */
       if( groupBySort ){
-        sqlite3VdbeAddOp2(v, OP_SorterNext, pAggInfo->sortingIdx, addrTopOfLoop);
+        sqlite3VdbeAddOp2(v, OP_SorterNext, pAggInfo->sortingIdx,addrTopOfLoop);
         VdbeCoverage(v);
       }else{
         sqlite3WhereEnd(pWInfo);
@@ -6885,7 +6885,6 @@ int sqlite3Select(
         explainSimpleCount(pParse, pTab, pBest);
       }else{
         int regAcc = 0;           /* "populate accumulators" flag */
-        int addrSkip;
 
         /* If there are accumulator registers but no min() or max() functions
         ** without FILTER clauses, allocate register regAcc. Register regAcc
@@ -6934,9 +6933,8 @@ int sqlite3Select(
         }
         updateAccumulator(pParse, regAcc, pAggInfo);
         if( regAcc ) sqlite3VdbeAddOp2(v, OP_Integer, 1, regAcc);
-        addrSkip = sqlite3WhereOrderByLimitOptLabel(pWInfo);
-        if( addrSkip!=sqlite3WhereContinueLabel(pWInfo) ){
-          sqlite3VdbeGoto(v, addrSkip);
+        if( minMaxFlag ){
+          sqlite3WhereMinMaxOptEarlyOut(v, pWInfo);
         }
         sqlite3WhereEnd(pWInfo);
         finalizeAggFunctions(pParse, pAggInfo);
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 6d1e598d9..8432fe20c 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -4341,6 +4341,7 @@ LogEst sqlite3WhereOutputRowCount(WhereInfo*);
 int sqlite3WhereIsDistinct(WhereInfo*);
 int sqlite3WhereIsOrdered(WhereInfo*);
 int sqlite3WhereOrderByLimitOptLabel(WhereInfo*);
+void sqlite3WhereMinMaxOptEarlyOut(Vdbe*,WhereInfo*);
 int sqlite3WhereIsSorted(WhereInfo*);
 int sqlite3WhereContinueLabel(WhereInfo*);
 int sqlite3WhereBreakLabel(WhereInfo*);
diff --git a/src/where.c b/src/where.c
index 0f219d439..adc688b4b 100644
--- a/src/where.c
+++ b/src/where.c
@@ -100,6 +100,29 @@ int sqlite3WhereOrderByLimitOptLabel(WhereInfo *pWInfo){
 }
 
 /*
+** While generating code for the min/max optimization, after handling
+** the aggregate-step call to min() or max(), check to see if any
+** additional looping is required.  If the output order is such that
+** we are certain that the correct answer has already been found, then
+** code an OP_Goto to by pass subsequent processing.
+**
+** Any extra OP_Goto that is coded here is an optimization.  The
+** correct answer should be obtained regardless.  This OP_Goto just
+** makes the answer appear faster.
+*/
+void sqlite3WhereMinMaxOptEarlyOut(Vdbe *v, WhereInfo *pWInfo){
+  WhereLevel *pInner;
+  if( !pWInfo->bOrderedInnerLoop ) return;
+  if( pWInfo->nOBSat==0 ) return;
+  pInner = &pWInfo->a[pWInfo->nLevel-1];
+  if( (pInner->pWLoop->wsFlags & WHERE_COLUMN_IN)==0 ){
+    sqlite3VdbeGoto(v, pWInfo->iBreak);
+  }else if( pInner->addrNxt!=pWInfo->iContinue ){
+    sqlite3VdbeGoto(v, pInner->addrNxt);
+  }
+}
+
+/*
 ** Return the VDBE address or label to jump to in order to continue
 ** immediately with the next row of a WHERE clause.
 */