From 475cb157b9c79464b707b8b9f68455c8311936b0 Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Fri, 12 May 2000 16:10:09 +0000
Subject: [PATCH] Squash some more CLUSTER bugs. Never has worked on
multiple-column indexes, apparently, nor on functional indexes with more than
one input column (force of natts = 1 was in the wrong branch of IF
statement). Coredumped if source relation contained any uncommitted tuples,
due to failure to test for success return from heap_fetch. Fetched tuple was
passed directly to heap_insert, which clobbers the TID and commit status in
the tuple header it's given, which meant that the source relation's tuples
all got trashed as the copy proceeded. Abort partway through, and you're
left with a lot of missing tuples. I wonder what else is lurking here ...
---
src/backend/commands/cluster.c | 23 ++++++++++++++++++-----
1 file changed, 18 insertions(+), 5 deletions(-)
diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c
index 688bd5148f6..15218cd6ce8 100644
--- a/src/backend/commands/cluster.c
+++ b/src/backend/commands/cluster.c
@@ -15,7 +15,7 @@
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/commands/cluster.c,v 1.52 2000/05/11 03:54:17 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/backend/commands/cluster.c,v 1.53 2000/05/12 16:10:09 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -258,11 +258,11 @@ copy_index(Oid OIDOldIndex, Oid OIDNewHeap)
Assert(pg_proc_Tuple);
pg_proc_Form = (Form_pg_proc) GETSTRUCT(pg_proc_Tuple);
namecpy(&(finfo->funcName), &(pg_proc_Form->proname));
+ natts = 1; /* function result is a single column */
}
else
{
finfo = (FuncIndexInfo *) NULL;
- natts = 1;
}
index_create(RelationGetRelationName(NewHeap),
@@ -273,7 +273,8 @@ copy_index(Oid OIDOldIndex, Oid OIDNewHeap)
natts,
Old_pg_index_Form->indkey,
Old_pg_index_Form->indclass,
- (uint16) 0, (Datum) NULL, NULL,
+ (uint16) 0, (Datum *) NULL,
+ (Node *) NULL, /* XXX where's the predicate? */
Old_pg_index_Form->indislossy,
Old_pg_index_Form->indisunique,
Old_pg_index_Form->indisprimary);
@@ -313,8 +314,20 @@ rebuildheap(Oid OIDNewHeap, Oid OIDOldHeap, Oid OIDOldIndex)
LocalHeapTuple.t_datamcxt = NULL;
LocalHeapTuple.t_data = NULL;
heap_fetch(LocalOldHeap, SnapshotNow, &LocalHeapTuple, &LocalBuffer);
- heap_insert(LocalNewHeap, &LocalHeapTuple);
- ReleaseBuffer(LocalBuffer);
+ if (LocalHeapTuple.t_data != NULL) {
+ /*
+ * We must copy the tuple because heap_insert() will overwrite
+ * the commit-status fields of the tuple it's handed, and the
+ * retrieved tuple will actually be in a disk buffer! Thus,
+ * the source relation would get trashed, which is bad news
+ * if we abort later on. (This was a bug in releases thru 7.0)
+ */
+ HeapTuple copiedTuple = heap_copytuple(&LocalHeapTuple);
+
+ ReleaseBuffer(LocalBuffer);
+ heap_insert(LocalNewHeap, copiedTuple);
+ heap_freetuple(copiedTuple);
+ }
pfree(ScanResult);
}
--
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