From: Richard Huxton <dev@archonet.com>
To: Jodi Kanter <jkanter@virginia.edu>,
	Postgres SQL List <pgsql-sql@postgresql.org>
Subject: Re: query assistance
Date: Tue, 4 Nov 2003 15:43:35 +0000
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On Tuesday 04 November 2003 15:16, Jodi Kanter wrote:
> Is there a straight forward way to pull out duplicates in a particular
> field given a value in another field?
> For example, I have a table that lists users and study names associated
> with those users. Each user can have one or more study names. My goal is
> to determine if any of these people have duplicate study names. There
> are duplicated study names across the system and that is ok. I just want
> to see if any users have duplicate study names among their studies.

Something like:

SELECT
  created_by, study_name, count(sty_pk)
FROM
  study
GROUP BY
  created_by, study_name
HAVING
  count(sty_pk) > 1;

-- 
  Richard Huxton
  Archonet Ltd