Fix ALTER COLUMN TYPE to preserve the tablespace and reloptions of indexes

it affects.  The original coding neglected tablespace entirely (causing
the indexes to move to the database's default tablespace) and for an index
belonging to a UNIQUE or PRIMARY KEY constraint, it would actually try to
assign the parent table's reloptions to the index :-(.  Per bug #3672 and
subsequent investigation.

8.0 and 8.1 did not have reloptions, but the tablespace bug is present.

1 files changed, 30 insertions, 1 deletions

diff --git a/src/backend/utils/cache/lsyscache.c b/src/backend/utils/cache/lsyscache.c
index 096a3cb942b..15b676dd590 100644
--- a/src/backend/utils/cache/lsyscache.c
+++ b/src/backend/utils/cache/lsyscache.c
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/cache/lsyscache.c,v 1.129 2005/10/15 02:49:31 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/cache/lsyscache.c,v 1.129.2.1 2007/10/13 15:55:58 tgl Exp $
  *
  * NOTES
  *	  Eventually, the index information should go through here, too.
@@ -1068,6 +1068,35 @@ get_rel_relkind(Oid relid)
 		return '\0';
 }
 
+/*
+ * get_rel_tablespace
+ *
+ *		Returns the pg_tablespace OID associated with a given relation.
+ *
+ * Note: InvalidOid might mean either that we couldn't find the relation,
+ * or that it is in the database's default tablespace.
+ */
+Oid
+get_rel_tablespace(Oid relid)
+{
+	HeapTuple	tp;
+
+	tp = SearchSysCache(RELOID,
+						ObjectIdGetDatum(relid),
+						0, 0, 0);
+	if (HeapTupleIsValid(tp))
+	{
+		Form_pg_class reltup = (Form_pg_class) GETSTRUCT(tp);
+		Oid			result;
+
+		result = reltup->reltablespace;
+		ReleaseSysCache(tp);
+		return result;
+	}
+	else
+		return InvalidOid;
+}
+
 
 /*				---------- TYPE CACHE ----------						 */