I've created a new shared catalog table pg_shdescription to store

comments on cluster global objects like databases, tablespaces, and
roles.

It touches a lot of places, but not much in the way of big changes.  The
only design decision I made was to duplicate the query and manipulation
functions rather than to try and have them handle both shared and local
comments.  I believe this is simpler for the code and not an issue for
callers because they know what type of object they are dealing with.
This has resulted in a shobj_description function analagous to
obj_description and backend functions [Create/Delete]SharedComments
mirroring the existing [Create/Delete]Comments functions.

pg_shdescription.h goes into src/include/catalog/

Kris Jurka

src/backend/parser/gram.y

@@ -11,7 +11,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/parser/gram.y,v 2.527 2006/02/11 22:17:18 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/parser/gram.y,v 2.528 2006/02/12 03:22:17 momjian Exp $
  *
  * HISTORY
  *	  AUTHOR			DATE			MAJOR EVENT
@@ -2953,11 +2953,12 @@ TruncateStmt:
  *
  *	COMMENT ON [ [ DATABASE | DOMAIN | INDEX | SEQUENCE | TABLE | TYPE | VIEW |
  *				   CONVERSION | LANGUAGE | OPERATOR CLASS | LARGE OBJECT |
- *				   CAST ] <objname> |
+ *				   CAST | COLUMN | SCHEMA | TABLESPACE | ROLE ] <objname> |
  *				 AGGREGATE <aggname> (<aggtype>) |
  *				 FUNCTION <funcname> (arg1, arg2, ...) |
  *				 OPERATOR <op> (leftoperand_typ, rightoperand_typ) |
  *				 TRIGGER <triggername> ON <relname> |
+ *				 CONSTRAINT <constraintname> ON <relname> |
  *				 RULE <rulename> ON <relname> ]
  *			   IS 'text'
  *
@@ -3088,6 +3089,8 @@ comment_type:
 			| TYPE_P							{ $$ = OBJECT_TYPE; }
 			| VIEW								{ $$ = OBJECT_VIEW; }
 			| CONVERSION_P						{ $$ = OBJECT_CONVERSION; }
+			| TABLESPACE						{ $$ = OBJECT_TABLESPACE; }
+			| ROLE								{ $$ = OBJECT_ROLE; }
 		;
 
 comment_text: