1. Vacuum is updated for MVCC.

2. Much faster btree tuples deletion in the case when first on page
   index tuple is deleted (no movement to the left page(s)).
3. Remember blkno of new root page in BTPageOpaque of
   left/right siblings when root page is splitted.

1 files changed, 7 insertions, 11 deletions

diff --git a/src/backend/access/nbtree/nbtsearch.c b/src/backend/access/nbtree/nbtsearch.c
index 9d9cc0f9aa..593a5453bc 100644
--- a/src/backend/access/nbtree/nbtsearch.c
+++ b/src/backend/access/nbtree/nbtsearch.c
@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtsearch.c,v 1.41 1999/02/21 03:48:27 scrappy Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtsearch.c,v 1.42 1999/03/28 20:31:58 vadim Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -706,15 +706,7 @@ _bt_next(IndexScanDesc scan, ScanDirection dir)
 	so = (BTScanOpaque) scan->opaque;
 	current = &(scan->currentItemData);
 
-	/*
-	 * XXX 10 may 91:  somewhere there's a bug in our management of the
-	 * cached buffer for this scan.  wei discovered it.  the following is
-	 * a workaround so he can work until i figure out what's going on.
-	 */
-
-	if (!BufferIsValid(so->btso_curbuf))
-		so->btso_curbuf = _bt_getbuf(rel, ItemPointerGetBlockNumber(current),
-									 BT_READ);
+	Assert (BufferIsValid(so->btso_curbuf));
 
 	/* we still have the buffer pinned and locked */
 	buf = so->btso_curbuf;
@@ -1069,7 +1061,11 @@ _bt_step(IndexScanDesc scan, Buffer *bufP, ScanDirection dir)
 
 	rel = scan->relation;
 	current = &(scan->currentItemData);
-	offnum = ItemPointerGetOffsetNumber(current);
+	/*
+	 * Don't use ItemPointerGetOffsetNumber or you risk to get
+	 * assertion due to ability of ip_posid to be equal 0.
+	 */
+	offnum = current->ip_posid;
 	page = BufferGetPage(*bufP);
 	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
 	so = (BTScanOpaque) scan->opaque;