Hmm, it seems nodeMaterial has been broken for a good long while;

closing a relcache entry more times than you open it is not cool.

diff --git a/src/backend/executor/nodeMaterial.c b/src/backend/executor/nodeMaterial.c
index ecf33f4c201ba9eccf3ee8d864870f3b5d988aa5..4348f89ccc9746b4a8c0b845fa3c31d001c1fc8e 100644 (file)
--- a/src/backend/executor/nodeMaterial.c
+++ b/src/backend/executor/nodeMaterial.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *   $Header: /cvsroot/pgsql/src/backend/executor/nodeMaterial.c,v 1.29 2000/01/26 05:56:23 momjian Exp $
+ *   $Header: /cvsroot/pgsql/src/backend/executor/nodeMaterial.c,v 1.30 2000/03/02 04:06:39 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -86,7 +86,7 @@ ExecMaterial(Material *node)
        estate->es_direction = ForwardScanDirection;
 
        /* ----------------
-        *   if we couldn't create the temp or current relations then
+        *   if we couldn't create the temp relation then
         *   we print a warning and return NULL.
         * ----------------
         */
@@ -97,13 +97,6 @@ ExecMaterial(Material *node)
            return NULL;
        }
 
-       currentRelation = matstate->csstate.css_currentRelation;
-       if (currentRelation == NULL)
-       {
-           elog(DEBUG, "ExecMaterial: current relation is NULL! aborting...");
-           return NULL;
-       }
-
        /* ----------------
         *   retrieve tuples from the subplan and
         *   insert them in the temporary relation
@@ -121,7 +114,6 @@ ExecMaterial(Material *node)
 
            ExecClearTuple(slot);
        }
-       currentRelation = tempRelation;
 
        /* ----------------
         *   restore to user specified direction
@@ -134,6 +126,7 @@ ExecMaterial(Material *node)
         *   sorted relation and update the sortstate information
         * ----------------
         */
+       currentRelation = tempRelation;
        currentScanDesc = heap_beginscan(currentRelation,       /* relation */
                                         ScanDirectionIsBackward(dir),
                                         SnapshotSelf,  /* seeself */
@@ -265,7 +258,6 @@ ExecInitMaterial(Material *node, EState *estate, Plan *parent)
     *  create the temporary relation
     * ----------------
     */
-/*   len = ExecTargetListLength(node->plan.targetlist); */
    tempDesc = ExecCreatR(tupType, _NONAME_RELATION_ID_);
 
    /* ----------------
@@ -273,7 +265,7 @@ ExecInitMaterial(Material *node, EState *estate, Plan *parent)
     * ----------------
     */
    matstate->mat_TempRelation = tempDesc;
-   matstate->csstate.css_currentRelation = tempDesc;
+   matstate->csstate.css_currentRelation = NULL;
 
    /* ----------------
     *  return relation oid of temporary relation in a list
@@ -312,12 +304,11 @@ ExecEndMaterial(Material *node)
    matstate = node->matstate;
    tempRelation = matstate->mat_TempRelation;
 
-   heap_drop(tempRelation);
-
    /* ----------------
-    *  close the temp relation and shut down the scan.
+    *  shut down the scan, but don't close the temp relation
     * ----------------
     */
+   matstate->csstate.css_currentRelation = NULL;
    ExecCloseR((Plan *) node);
 
    /* ----------------
@@ -332,6 +323,13 @@ ExecEndMaterial(Material *node)
     * ----------------
     */
    ExecClearTuple(matstate->csstate.css_ScanTupleSlot);
+
+   /* ----------------
+    *  delete the temp relation
+    * ----------------
+    */
+   if (tempRelation != NULL)
+       heap_drop(tempRelation);
 }
 
 /* ----------------------------------------------------------------