From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Wed, 12 Oct 2005 17:18:15 +0000 (+0000)
Subject: Fix longstanding bug found by Atsushi Ogawa: _bt_check_unique would mark
X-Git-Url: http://git.postgresql.org/gitweb/static/gitweb.js?a=commitdiff_plain;h=f729a79d1bac1a211be0582c8dec706d5f8bac07;p=users%2Fbernd%2Fpostgres.git

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 c14d554752..2f3edc3043 100644
--- a/src/backend/access/nbtree/nbtinsert.c
+++ b/src/backend/access/nbtree/nbtinsert.c
@@ -266,7 +266,10 @@ _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);
 				}