Add a new system view, pg_cursors, that displays the currently available

cursors. Patch from Joachim Wieland, review and ediorialization by Neil
Conway. The view lists cursors defined by DECLARE CURSOR, using SPI, or
via the Bind message of the frontend/backend protocol. This means the
view does not list the unnamed portal or the portal created to implement
EXECUTE. Because we do list SPI portals, there might be more rows in
this view than you might expect if you are using SPI implicitly (e.g.
via a procedural language).

Per recent discussion on -hackers, the query string included in the
view for cursors defined by DECLARE CURSOR is based on
debug_query_string. That means it is not accurate if multiple queries
separated by semicolons are submitted as one query string. However,
there doesn't seem a trivial fix for that: debug_query_string
is better than nothing. I also changed SPI_cursor_open() to include
the source text for the portal it creates: AFAICS there is no reason
not to do this.

Update the documentation and regression tests, bump the catversion.

1 files changed, 5 insertions, 5 deletions

diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index f523984e5a8..f0afdbba367 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -10,7 +10,7 @@
  * Copyright (c) 2002-2005, PostgreSQL Global Development Group
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/prepare.c,v 1.46 2006/01/16 18:15:30 neilc Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/prepare.c,v 1.47 2006/01/18 06:49:26 neilc Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -162,11 +162,11 @@ ExecuteQuery(ExecuteStmt *stmt, ParamListInfo params,
 		paramLI = EvaluateParams(estate, stmt->params, entry->argtype_list);
 	}
 
-	/*
-	 * Create a new portal to run the query in
-	 */
+	/* Create a new portal to run the query in */
 	portal = CreateNewPortal();
-
+	/* Don't display the portal in pg_cursors, it is for internal use only */
+	portal->visible = false;
+	
 	/*
 	 * For CREATE TABLE / AS EXECUTE, make a copy of the stored query so that
 	 * we can modify its destination (yech, but this has always been ugly).