Thinking further, it seems we had better also copy down resorigtbl/resorigcol

to ensure that SubqueryScan elimination doesn't change the behavior of
reporting of original column sources.

diff --git a/src/backend/optimizer/plan/setrefs.c b/src/backend/optimizer/plan/setrefs.c
index 9f078924c2533b5cd824492fde52068caddaea62..e6f97fa0815216e1fe99dca20be021a22eec4edb 100644 (file)
--- a/src/backend/optimizer/plan/setrefs.c
+++ b/src/backend/optimizer/plan/setrefs.c
@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *   $PostgreSQL: pgsql/src/backend/optimizer/plan/setrefs.c,v 1.116 2005/11/03 17:34:03 tgl Exp $
+ *   $PostgreSQL: pgsql/src/backend/optimizer/plan/setrefs.c,v 1.117 2005/11/03 17:45:29 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -382,9 +382,10 @@ set_subqueryscan_references(SubqueryScan *plan, List *rtable)
                                       result->initPlan);
 
        /*
-        * we also have to transfer the SubqueryScan's result-column names
+        * We also have to transfer the SubqueryScan's result-column names
         * into the subplan, else columns sent to client will be improperly
-        * labeled if this is the topmost plan level.
+        * labeled if this is the topmost plan level.  Copy the "source
+        * column" information too.
         */
        forboth(lp, plan->scan.plan.targetlist, lc, result->targetlist)
        {
@@ -392,6 +393,8 @@ set_subqueryscan_references(SubqueryScan *plan, List *rtable)
            TargetEntry *ctle = (TargetEntry *) lfirst(lc);
 
            ctle->resname = ptle->resname;
+           ctle->resorigtbl = ptle->resorigtbl;
+           ctle->resorigcol = ptle->resorigcol;
        }
    }
    else