diff options
Diffstat (limited to 'src/backend/optimizer/plan/createplan.c')
| -rw-r--r-- | src/backend/optimizer/plan/createplan.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/src/backend/optimizer/plan/createplan.c b/src/backend/optimizer/plan/createplan.c index 185f0625a78..bd19f43d586 100644 --- a/src/backend/optimizer/plan/createplan.c +++ b/src/backend/optimizer/plan/createplan.c @@ -787,10 +787,14 @@ use_physical_tlist(PlannerInfo *root, Path *path, int flags) * to emit any sort/group columns that are not simple Vars. (If they are * simple Vars, they should appear in the physical tlist, and * apply_pathtarget_labeling_to_tlist will take care of getting them - * labeled again.) + * labeled again.) We also have to check that no two sort/group columns + * are the same Var, else that element of the physical tlist would need + * conflicting ressortgroupref labels. */ if ((flags & CP_LABEL_TLIST) && path->pathtarget->sortgrouprefs) { + Bitmapset *sortgroupatts = NULL; + i = 0; foreach(lc, path->pathtarget->exprs) { @@ -799,7 +803,14 @@ use_physical_tlist(PlannerInfo *root, Path *path, int flags) if (path->pathtarget->sortgrouprefs[i]) { if (expr && IsA(expr, Var)) - /* okay */ ; + { + int attno = ((Var *) expr)->varattno; + + attno -= FirstLowInvalidHeapAttributeNumber; + if (bms_is_member(attno, sortgroupatts)) + return false; + sortgroupatts = bms_add_member(sortgroupatts, attno); + } else return false; } |