From: Octavio Alvarez <alvarezp@alvarezp.ods.org>
To: pgsql-sql@postgresql.org
Subject: LEFT JOIN on one and/or another column
Date: Wed, 28 Jan 2004 20:27:00 -0800 (PST)
Message-ID: <1533.63.84.67.25.1075350420.squirrel@alvarezp.ods.org> (raw)
Hi. I have a table with two foreign keys (1 field each), like in
id | serial
ext_key_original | integer
ext_key_exception | integer
They mean different things, as one refers to a typical value, and the
other one refers to an exception that applies for that tuple.
Each key references a different table, one with typical data, and one with
exception data.
I'd like to join on the original, except when exception <> NULL, but I
can't quite figure out how to do so.
Can anyone help?
Thanks you. :-)
Octavio.
--
Octavio Alvarez.
E-mail: alvarezp@alvarezp.ods.org.
Agradezco que sus correos sean enviados siempre a esta dirección.
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To: pgsql-sql@postgresql.org
Cc: alvarezp@alvarezp.ods.org
Subject: Re: LEFT JOIN on one and/or another column
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