Received: from localhost (postgresql.org [64.49.215.8])
	by postgresql.org (Postfix) with ESMTP id 9871B4770BD
	for <pgsql-sql@postgresql.org>; Fri, 13 Dec 2002 13:21:48 -0500 (EST)
Received: from sss.pgh.pa.us (unknown [192.204.191.242])
	by postgresql.org (Postfix) with ESMTP id 6064547703D
	for <pgsql-sql@postgresql.org>; Fri, 13 Dec 2002 13:20:50 -0500 (EST)
Received: from sss2.sss.pgh.pa.us (tgl@localhost [127.0.0.1])
	by sss.pgh.pa.us (8.12.6/8.12.6) with ESMTP id gBDIKopd006049;
	Fri, 13 Dec 2002 13:20:50 -0500 (EST)
To: cgg007@yahoo.com
Cc: pgsql-sql@postgresql.org
Subject: Re: A Costly function + LIMIT 
In-reply-to: <20021213181435.31771.qmail@web13804.mail.yahoo.com> 
References: <20021213181435.31771.qmail@web13804.mail.yahoo.com>
Comments: In-reply-to Chris Gamache <cgg007@yahoo.com>
	message dated "Fri, 13 Dec 2002 10:14:35 -0800"
Date: Fri, 13 Dec 2002 13:20:49 -0500
Message-ID: <6048.1039803649@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
X-Virus-Scanned: by AMaViS new-20020517
X-Archive-Number: 200212/182
X-Sequence-Number: 10770

Chris Gamache <cgg007@yahoo.com> writes:
> It runs "widget" on 10000 records. The damage would be negligible if it could
> run on the 100... 

So do the function calculation outside the UNION/ORDER BY.

SELECT name, address, city, state, zip, widget(name, address, city, state,
zip)
FROM
((SELECT * FROM eastern_usa 
  ORDER BY state, city, zip, name 
  LIMIT 5000
 UNION ALL
  SELECT * FROM western_usa 
  ORDER BY state, city, zip, name 
  LIMIT 5000)
 ORDER BY 4, 3, 5, 1 LIMIT 100 OFFSET 0) ss;

You might have to fool with the parenthesization a little to get it
to parse ...

			regards, tom lane