From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Wed, 12 Oct 2005 17:18:45 +0000 (+0000)
Subject: Fix longstanding bug found by Atsushi Ogawa: _bt_check_unique would mark
X-Git-Tag: REL7_3_12~8
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=10f14e6e0dfbc5a82d3dc8be7f6be4a4f1bdd72d;p=postgresql

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 ad52b0d3fa..230b96422c 100644
--- a/src/backend/access/nbtree/nbtinsert.c
+++ b/src/backend/access/nbtree/nbtinsert.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtinsert.c,v 1.96.2.1 2003/02/21 18:24:54 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtinsert.c,v 1.96.2.2 2005/10/12 17:18:45 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -266,7 +266,10 @@ _bt_check_unique(Relation rel, BTItem btitem, Relation heapRel,
 						HEAPTUPLE_DEAD)
 					{
 						curitemid->lp_flags |= LP_DELETE;
-						SetBufferCommitInfoNeedsSave(buf);
+						if (nbuf != InvalidBuffer)
+							SetBufferCommitInfoNeedsSave(nbuf);
+						else
+							SetBufferCommitInfoNeedsSave(buf);
 					}
 					if (sv_infomask != htup.t_data->t_infomask)
 						SetBufferCommitInfoNeedsSave(hbuffer);