Fix possible duplicate tuples while GiST scan. Now page is processed

at once and ItemPointers are collected in memory.

Remove tuple's killing by killtuple() if tuple was moved to another
page - it could produce unaceptable overhead.

Backpatch up to 8.1 because the bug was introduced by GiST's concurrency support.

1 files changed, 8 insertions, 1 deletions

diff --git a/src/include/access/gist_private.h b/src/include/access/gist_private.h
index e6ca50a702f..e823928c3e2 100644
--- a/src/include/access/gist_private.h
+++ b/src/include/access/gist_private.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/access/gist_private.h,v 1.28 2008/01/01 19:45:56 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/access/gist_private.h,v 1.28.2.1 2008/08/23 10:40:03 teodor Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -75,6 +75,13 @@ typedef struct GISTScanOpaqueData
 	ItemPointerData curpos;
 	Buffer		markbuf;
 	ItemPointerData markpos;
+
+	ItemPointerData	pageData[BLCKSZ/sizeof(IndexTupleData)];
+	OffsetNumber	nPageData;
+	OffsetNumber	curPageData;
+	ItemPointerData	markPageData[BLCKSZ/sizeof(IndexTupleData)];
+	OffsetNumber	markNPageData;
+	OffsetNumber	markCurPageData;
 } GISTScanOpaqueData;
 
 typedef GISTScanOpaqueData *GISTScanOpaque;