Fix longstanding bug found by Atsushi Ogawa: _bt_check_unique would mark

the wrong buffer dirty when trying to kill a dead index entry that's on
a page after the one it started on.  No risk of data corruption, just
inefficiency, but still a bug.

diff --git a/src/backend/access/nbtree/nbtinsert.c b/src/backend/access/nbtree/nbtinsert.c
index 6e0b059ae136906c0484b3e2732232b9897351db..c73ba358ec14891cb5a774b4ab4baddabc34b649 100644 (file)
--- a/src/backend/access/nbtree/nbtinsert.c
+++ b/src/backend/access/nbtree/nbtinsert.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *       $PostgreSQL: pgsql/src/backend/access/nbtree/nbtinsert.c,v 1.125 2005/09/24 22:54:35 tgl Exp $
+ *       $PostgreSQL: pgsql/src/backend/access/nbtree/nbtinsert.c,v 1.126 2005/10/12 17:18:03 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -261,7 +261,10 @@ _bt_check_unique(Relation rel, BTItem btitem, Relation heapRel,
                                                                                                 hbuffer) == HEAPTUPLE_DEAD)
                                        {
                                                curitemid->lp_flags |= LP_DELETE;
-                                               SetBufferCommitInfoNeedsSave(buf);
+                                               if (nbuf != InvalidBuffer)
+                                                       SetBufferCommitInfoNeedsSave(nbuf);
+                                               else
+                                                       SetBufferCommitInfoNeedsSave(buf);
                                        }
                                        LockBuffer(hbuffer, BUFFER_LOCK_UNLOCK);
                                }