From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andrew Perrin <clists@perrin.socsci.unc.edu>
Cc: pgsql-sql@postgresql.org
Subject: Re: LIMIT within UNION?
Date: Thu, 12 Sep 2002 15:34:07 -0400
Message-ID: <9272.1031859247@sss.pgh.pa.us> (raw)
In-Reply-To: <Pine.LNX.4.21.0209121454540.32000-100000@perrin.socsci.unc.edu>
References: <Pine.LNX.4.21.0209121454540.32000-100000@perrin.socsci.unc.edu>
Andrew Perrin <clists@perrin.socsci.unc.edu> writes:
> SELECT ... FROM participants
> WHERE typenr=1 AND <eligibility>
> UNION
> SELECT ... FROM participants
> WHERE typenr=2 LIMIT 172
> ORDER BY zip;
I think you need
SELECT * FROM
(
SELECT ... FROM participants
WHERE typenr=1 AND <eligibility>
UNION
(SELECT ... FROM participants
WHERE typenr=2 LIMIT 172)
) ss
ORDER BY zip;
Not sure if the inner set of parens is essential, but it might be.
The outer SELECT superstructure is definitely necessary to give a
place to hang the ORDER BY on.
regards, tom lane
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-sql@postgresql.org
Cc: tgl@sss.pgh.pa.us, clists@perrin.socsci.unc.edu
Subject: Re: LIMIT within UNION?
In-Reply-To: <9272.1031859247@sss.pgh.pa.us>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox