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From: Franco Bruno Borghesi <franco@akyasociados.com.ar>
To: rudi@oasis.net.au
Cc: pgsql-sql@postgresql.org
Subject: Re: Delete duplicates
Date: Sun, 22 Jun 2003 18:17:16 -0300 (ART)
Message-ID: <2976.200.59.66.253.1056316636.squirrel@webmail.akyasociados.com.ar> (raw)
In-Reply-To: <20030622091522.M37248@oasis.net.au>
References: <20030622091522.M37248@oasis.net.au>

try this

DELETE FROM aap WHERE  id NOT IN (
   SELECT max(id)
   FROM aap
   GROUP BY keyword
);

>
>
> Hi,
>
> I have a table with duplicates and trouble with my SQL.
> I'd like to keep a single record and remove older duplicates.
> For example below of the 6 recods I'd like to keep records
> 4 and 6.
>
> TABLE: aap
> id |     keyword
> ----+-----------------
>  1 | LEAGUE PANTHERS
>  2 | LEAGUE PANTHERS
>  3 | LEAGUE PANTHERS
>  4 | LEAGUE PANTHERS
>  5 | LEAGUE BRONCOS
>  6 | LEAGUE BRONCOS
>
> Here is my SQL so far, it will select records 1 to 5 instead
> of 1,2,3 and 5 only.
>
> Any help greatly appreciated. I think I need a Group By somewhere in
> there.
>
> select a1.id
> from aap a1
> where id < ( SELECT max(id) FROM aap AS a2 )
> AND EXISTS
> (
> SELECT *
> FROM aap AS a2
> WHERE a1.keyword = a2.keyword
> )
>
> Regards
> Rudi.
>
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