From: "tjk@tksoft.com" <tjk@tksoft.com>
Message-Id: <200104041422.HAA10925@smtp3.tksoft.com>
Subject: Re: outer joins
To: asakmanas@grafton.lt (=?iso-8859-4?Q?Algirdas_=A9akmanas?=)
Date: Wed, 4 Apr 2001 07:22:43 -0700 (PDT)
Cc: pgsql-sql@postgresql.org
In-Reply-To: <NFBBJHKIMLJDMKFOHEPEEECFCAAA.asakmanas@grafton.lt> from
	"=?iso-8859-4?Q?Algirdas_=A9akmanas?=" at Apr 04, 2001 01:03:11 PM
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Algirdas,

This should do the trick:

SELECT a.id,b.name FROM a,b WHERE a.id=b.id UNION SELECT id,null FROM a WHERE id NOT IN (SELECT id FROM b);


Troy

> 
> Hi all,
> 
> I'm new to postgre, I've changed my work and consequently now i'm moving
> from MS plaform.
> In MS SQL there are such constructs left or right outer join, in postgres
> there are no such thing
> 
> Can You offer me strategy to make query that selects from table (a) and
> joins to it another (b)
> on e.g. a.id=b.aid but joins so that in case there is no value in table b
> NULL is left in result:
> in MS SQL i've used query:
> 
> select a.id, b.name from a left outer join b on a.id=b.aid
> 
> table a          table b
> 
> id |             aid | name
> -----------      ----------------
> 1                1   | Tom
> 2                3   | Sam
> 
> result:
> a.id  |  b.name
> ---------------------
> 1     | Tom
> 2     | NULL
> 
> thank you in advance
> 
> Algirdas Šakmanas
> IT manager
> +370 99 90369
> asakmanas@grafton.lt
> Grafton Entertainment
> http://www.tvnet.lt
> 
> 
> 
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