From: 8q5tmkyqry@sneakemail.com
To: pgsql-sql@postgresql.org
Subject: selecting rows tagged with "a" but not "b"
Date: Mon, 1 Feb 2010 13:31:38 +0000
Message-ID: <11366-1265031099-334353@sneakemail.com> (raw)
Hi,
I have a two tables:
article
articleID, name, content
tags
articleID, tag
I want to find all articles that are tagged with "a" but not "b"
how do I do this?
what I'd like to do is:
<wishful thinking>
select articleID from tags where tag="a"
SUBTRACT
select articleID from tags where tab="b"
</wishful thinking>
how do I do this in real SQL?
thanks
Darrell
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