Simplification of the skip-ahead-distinct logic. There is still an issue

with handling COLLATE.

FossilOrigin-Name: 57c5173b6376a76013b0611ce9770100bd8c04e80402e35d821d8614709f4795

1 files changed, 15 insertions, 16 deletions

diff --git a/src/where.c b/src/where.c
index a846e2e82..dbb8111d1 100644
--- a/src/where.c
+++ b/src/where.c
@@ -3437,7 +3437,7 @@ static int whereLoopAddAll(WhereLoopBuilder *pBuilder){
 }
 
 /*
-** Examine a WherePath (with the addition of the extra WhereLoop of the 5th
+** Examine a WherePath (with the addition of the extra WhereLoop of the 6th
 ** parameters) to see if it outputs rows in the requested ORDER BY
 ** (or GROUP BY) without requiring a separate sort operation.  Return N:
 ** 
@@ -4849,6 +4849,7 @@ void sqlite3WhereEnd(WhereInfo *pWInfo){
     pLoop = pLevel->pWLoop;
     if( pLevel->op!=OP_Noop ){
 #ifndef SQLITE_DISABLE_SKIPAHEAD_DISTINCT
+      int addrSeek = 0;
       int n = -1;
       int j, k, op;
       int r1 = pParse->nMem+1;
@@ -4897,25 +4898,23 @@ void sqlite3WhereEnd(WhereInfo *pWInfo){
         }
         pParse->nMem += n;
         op = pLevel->op==OP_Prev ? OP_SeekLT : OP_SeekGT;
-        k = sqlite3VdbeAddOp4Int(v, op, pLevel->iIdxCur, 0, r1, n);
+        addrSeek = sqlite3VdbeAddOp4Int(v, op, pLevel->iIdxCur, 0, r1, n);
         VdbeCoverageIf(v, op==OP_SeekLT);
         VdbeCoverageIf(v, op==OP_SeekGT);
         sqlite3VdbeAddOp2(v, OP_Goto, 1, pLevel->p2);
-        sqlite3VdbeResolveLabel(v, pLevel->addrCont);
-        sqlite3VdbeAddOp3(v, pLevel->op, pLevel->p1, pLevel->p2, pLevel->p3);
-        sqlite3VdbeJumpHere(v, k);
-      }else
-#endif /* SQLITE_DISABLE_SKIPAHEAD_DISTINCT */
-      {
-        /* The common case: Advance to the next row */
-        sqlite3VdbeResolveLabel(v, pLevel->addrCont);
-        sqlite3VdbeAddOp3(v, pLevel->op, pLevel->p1, pLevel->p2, pLevel->p3);
-        sqlite3VdbeChangeP5(v, pLevel->p5);
-        VdbeCoverage(v);
-        VdbeCoverageIf(v, pLevel->op==OP_Next);
-        VdbeCoverageIf(v, pLevel->op==OP_Prev);
-        VdbeCoverageIf(v, pLevel->op==OP_VNext);
       }
+#endif /* SQLITE_DISABLE_SKIPAHEAD_DISTINCT */
+      /* The common case: Advance to the next row */
+      sqlite3VdbeResolveLabel(v, pLevel->addrCont);
+      sqlite3VdbeAddOp3(v, pLevel->op, pLevel->p1, pLevel->p2, pLevel->p3);
+      sqlite3VdbeChangeP5(v, pLevel->p5);
+      VdbeCoverage(v);
+      VdbeCoverageIf(v, pLevel->op==OP_Next);
+      VdbeCoverageIf(v, pLevel->op==OP_Prev);
+      VdbeCoverageIf(v, pLevel->op==OP_VNext);
+#ifndef SQLITE_DISABLE_SKIPAHEAD_DISTINCT
+      if( addrSeek ) sqlite3VdbeJumpHere(v, addrSeek);
+#endif
     }else{
       sqlite3VdbeResolveLabel(v, pLevel->addrCont);
     }