thanks alot - DISTINCT ON has exactly the behaviour i was looking for!
- thomas
----- Original Message -----
From: "Bruno Wolff III" <bruno@wolff.to>
To: <me@alternize.com>
Cc: <pgsql-novice@postgresql.org>
Sent: Sunday, March 26, 2006 1:59 AM
Subject: Re: [NOVICE] help with a view (join-query)
> On Fri, Mar 24, 2006 at 19:36:34 +0100,
> me@alternize.com wrote:
>> hi list
>>
>> currently in our database, a "person" contains a relation to one or more
>> "events". i now need a view where each person is listed exactly once, and
>> to each person only one (of possible more) events is listed. it does not
>> matter which ones of the events are shown. when doing a normal JOIN, the
>> resultset might return more than one record per person (for each event
>> one line).
>> is there an easy way to build a query that fullfills my needs? i'd rather
>> not check programmatically if i already listed the person or not.
>
> You could use the Postgres specific extension DISTINCT ON to do this. You
> can
> even use ORDER BY to make which row you grab deterministic.
>
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