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Reply-To: <wweng@kencast.com>
From: "Wei Weng" <wweng@kencast.com>
To: <pgsql-sql@postgresql.org>
Subject: Re: NULL values or not?
Date: Fri, 21 Dec 2001 16:37:52 -0500
Message-ID: <NEBBLAIMPMNDAPBMNGJNCEHKCCAA.wweng@kencast.com>
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Forgive my ignorance, but what exactly is a "multi-column" join?
<snip>
>  gb_accessions, the clones who are missing GB will not show up with a
>  blank GB, instead they will not show up at all! You can get around this
>  with OUTER JOINS, but OUTER JOINs are not dependable for multi-column
>  joins.
<snip>

I also used a lot of NULLs in my table schemas though never in the
primary(foreign) keys. Is that bad?

Thank you.

==========
Wei Weng
Network Software Engineer
KenCast Inc.