Back-patch fix for VACUUM being confused by SELECT FOR UPDATE of tuple

that was previously outdated by a transaction that later aborted.
Also, prevent VACUUM from being called inside function.

diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 5def52a9a2513ff5293193c188b102ec5b744e67..75f4c189e323693cb2e0e39832dde3f7fc0c3c39 100644 (file)
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -13,7 +13,7 @@
  *
  *
  * IDENTIFICATION
- *       $Header: /cvsroot/pgsql/src/backend/commands/vacuum.c,v 1.213.2.2 2002/09/30 19:45:57 tgl Exp $
+ *       $Header: /cvsroot/pgsql/src/backend/commands/vacuum.c,v 1.213.2.3 2003/01/21 19:38:21 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -187,6 +187,10 @@ vacuum(VacuumStmt *vacstmt)
        if (IsTransactionBlock())
                elog(ERROR, "%s cannot run inside a BEGIN/END block", stmttype);
 
+       /* Running VACUUM from a function would free the function context */
+       if (!MemoryContextContains(QueryContext, vacstmt))
+               elog(ERROR, "%s cannot be executed from a function", stmttype);
+                        
        /*
         * Send info about dead objects to the statistics collector
         */
@@ -1320,7 +1324,8 @@ scan_heap(VRelStats *vacrelstats, Relation onerel,
                usable_free_size = 0;
        }
 
-       if (usable_free_size > 0 && num_vtlinks > 0)
+       /* don't bother to save vtlinks if we will not call repair_frag */
+       if (fraged_pages->num_pages > 0 && num_vtlinks > 0)
        {
                qsort((char *) vtlinks, num_vtlinks, sizeof(VTupleLinkData),
                          vac_cmp_vtlinks);
@@ -1602,7 +1607,8 @@ repair_frag(VRelStats *vacrelstats, Relation onerel,
                         */
                        if ((tuple.t_data->t_infomask & HEAP_UPDATED &&
                         !TransactionIdPrecedes(tuple.t_data->t_xmin, OldestXmin)) ||
-                               (!(tuple.t_data->t_infomask & HEAP_XMAX_INVALID) &&
+                               (!(tuple.t_data->t_infomask & (HEAP_XMAX_INVALID |
+                                                                                          HEAP_MARKED_FOR_UPDATE)) &&
                                 !(ItemPointerEquals(&(tuple.t_self),
                                                                         &(tuple.t_data->t_ctid)))))
                        {
@@ -1633,7 +1639,8 @@ repair_frag(VRelStats *vacrelstats, Relation onerel,
                                 * If this tuple is in the begin/middle of the chain then
                                 * we have to move to the end of chain.
                                 */
-                               while (!(tp.t_data->t_infomask & HEAP_XMAX_INVALID) &&
+                               while (!(tp.t_data->t_infomask & (HEAP_XMAX_INVALID |
+                                                                                                 HEAP_MARKED_FOR_UPDATE)) &&
                                           !(ItemPointerEquals(&(tp.t_self),
                                                                                   &(tp.t_data->t_ctid))))
                                {