Fix portal management code to support non-default command completion tags for

portals using PORTAL_UTIL_SELECT strategy.  This is currently significant only
for FETCH queries, which are supposed to include a count in the tag.  Seems
it's been broken since 7.4, but nobody noticed before Knut Lehre.

diff --git a/src/backend/tcop/pquery.c b/src/backend/tcop/pquery.c
index 26ef0542696acaa938065fb4326411cd49a59e17..372b722d8ab93665318b60f374808d62706ace4d 100644 (file)
--- a/src/backend/tcop/pquery.c
+++ b/src/backend/tcop/pquery.c
@@ -37,6 +37,7 @@ static void ProcessQuery(Query *parsetree,
                         ParamListInfo params,
                         DestReceiver *dest,
                         char *completionTag);
+static void FillPortalStore(Portal portal);
 static uint32 RunFromStore(Portal portal, ScanDirection direction, long count,
                         DestReceiver *dest);
 static long PortalRunSelect(Portal portal, bool forward, long count,
@@ -580,16 +581,7 @@ PortalRun(Portal portal, long count,
                                 * storing its results in the portal's tuplestore.
                                 */
                                if (!portal->portalUtilReady)
-                               {
-                                       DestReceiver *treceiver;
-
-                                       PortalCreateHoldStore(portal);
-                                       treceiver = CreateDestReceiver(Tuplestore, portal);
-                                       PortalRunUtility(portal, linitial(portal->parseTrees),
-                                                                        treceiver, NULL);
-                                       (*treceiver->rDestroy) (treceiver);
-                                       portal->portalUtilReady = true;
-                               }
+                                       FillPortalStore(portal);
 
                                /*
                                 * Now fetch desired portion of results.
@@ -819,6 +811,35 @@ PortalRunSelect(Portal portal,
        return nprocessed;
 }
 
+/*
+ * FillPortalStore
+ *             Run the query and load result tuples into the portal's tuple store.
+ *
+ * This is used for PORTAL_UTIL_SELECT cases only.
+ */
+static void
+FillPortalStore(Portal portal)
+{
+       DestReceiver *treceiver;
+       char            completionTag[COMPLETION_TAG_BUFSIZE];
+
+       PortalCreateHoldStore(portal);
+       treceiver = CreateDestReceiver(Tuplestore, portal);
+
+       completionTag[0] = '\0';
+
+       PortalRunUtility(portal, linitial(portal->parseTrees),
+                                        treceiver, completionTag);
+
+       /* Override default completion tag with actual command result */
+       if (completionTag[0] != '\0')
+               portal->commandTag = pstrdup(completionTag);
+
+       (*treceiver->rDestroy) (treceiver);
+
+       portal->portalUtilReady = true;
+}
+
 /*
  * RunFromStore
  *             Fetch tuples from the portal's tuple store.
@@ -1033,7 +1054,7 @@ PortalRunMulti(Portal portal,
                 * Increment command counter between queries, but not after the
                 * last one.
                 */
-               if (planlist_item != NULL)
+               if (lnext(planlist_item) != NULL)
                        CommandCounterIncrement();
 
                /*
@@ -1120,6 +1141,21 @@ PortalRunFetch(Portal portal,
                                result = DoPortalRunFetch(portal, fdirection, count, dest);
                                break;
 
+                       case PORTAL_UTIL_SELECT:
+
+                               /*
+                                * If we have not yet run the utility statement, do so,
+                                * storing its results in the portal's tuplestore.
+                                */
+                               if (!portal->portalUtilReady)
+                                       FillPortalStore(portal);
+
+                               /*
+                                * Now fetch desired portion of results.
+                                */
+                               result = DoPortalRunFetch(portal, fdirection, count, dest);
+                               break;
+
                        default:
                                elog(ERROR, "unsupported portal strategy");
                                result = 0;             /* keep compiler quiet */
@@ -1170,7 +1206,8 @@ DoPortalRunFetch(Portal portal,
 {
        bool            forward;
 
-       Assert(portal->strategy == PORTAL_ONE_SELECT);
+       Assert(portal->strategy == PORTAL_ONE_SELECT ||
+                  portal->strategy == PORTAL_UTIL_SELECT);
 
        switch (fdirection)
        {