From: Adam Rosi-Kessel <adam@rosi-kessel.org>
To: Michael Glaesemann <grzm@myrealbox.com>
Cc: pgsql-sql@postgresql.org
Subject: Re: ORDER BY does not work as expected with multiple joins
Date: Fri, 13 Jan 2006 10:22:57 -0500
Message-ID: <43C7C5D1.9030600@rosi-kessel.org> (raw)
In-Reply-To: <3AA68074-D959-442F-8329-79D09D5F9129@myrealbox.com>
References: <43C7BA12.90103@rosi-kessel.org>
<3AA68074-D959-442F-8329-79D09D5F9129@myrealbox.com>
Thanks for your helpful response.
Michael Glaesemann wrote:
> I don't seem to have a problem with the ordering given your data. I'm
> not sure why you're doing right and left joins, though. You might want
> to use left joins if you have NULL id1 or id2, but otherwise just plain
> JOIN should work fine. I've included both your SELECT (slightly modified
> to avoid using key words) and how I'd probably right the statement.
id1 will always have a value but id2 can be NULL. So should I do a left JOIN
on id2 but a plain JOIN on id1? Is there a disadvantage to using a left JOIN
where it is not necessary?
Adam
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To: pgsql-sql@postgresql.org
Cc: adam@rosi-kessel.org, grzm@myrealbox.com
Subject: Re: ORDER BY does not work as expected with multiple joins
In-Reply-To: <43C7C5D1.9030600@rosi-kessel.org>
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