Received: from fep02-svc.tin.it (mta02-acc.tin.it [212.216.176.33])
	by hub.org (8.9.2/8.9.1) with ESMTP id DAA43765
	for <pgsql-interfaces@postgreSQL.org>;
	Mon, 8 Mar 1999 03:05:23 -0500 (EST)
	(envelope-from sbragion.denis@usa.net)
Received: from Server.InfoTecna.com ([212.216.18.44]) by fep02-svc.tin.it
	(InterMail v4.0 201-221-105) with ESMTP
	id <19990308080450.XDIG6870.fep02-svc@Server.InfoTecna.com>;
	Mon, 8 Mar 1999 09:04:50 +0100
Received: from tm3 (Tm3.InfoTecna.com [192.168.1.3])
	by Server.InfoTecna.com (8.8.5/8.8.5) with SMTP id JAA21849;
	Mon, 8 Mar 1999 09:02:24 +0100
Message-Id: <3.0.6.32.19990308090221.00b3bb10@MBox.InfoTecna.com>
X-Sender: denis@MBox.InfoTecna.com
X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.6 (32)
Date: Mon, 08 Mar 1999 09:02:21 +0100
To: "Ken J. Wright" <ken@ori-ind.com>, pgsql-interfaces@postgreSQL.org
From: Denis Sbragion <sbragion.denis@usa.net>
Subject: Re: [INTERFACES] outer joins
In-Reply-To: <3.0.32.19990307190027.00889d20@ren.cncware.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"

Hello,

At 19.00 07/03/99 -0800, you wrote:
>So, is there an eloquent (or not) way to fake an outer join in PostgreSQL?

yes! Example of a workaround using unions:

select
	X.a, X.b,
	Y.a, Y.b
from
	X left outer join Y on X.a = Y.a

becomes

select 
	X.a, X.b,
	Y.a, Y.b
from
	X,Y
where
	X.a = Y.a
union
select 
	X.a, X.b,
	null, null
from
	X
where
	not exists (select * from Y where Y.a = X.a)

Little cumbersome but it works.

Bye!

	Sbragion Denis
	InfoTecna
	Tel, Fax: +39 039 2324054
	URL: http://space.tin.it/internet/dsbragio