From: Germán Gutiérrez <germangutierrezg@entelchile.net>
To: pgsql-sql@postgresql.org
Subject: Re: Delete duplicates
Date: Sun, 22 Jun 2003 14:33:06 -0400
Message-ID: <000a01c338ec$b9635d00$eaf1fea9@german> (raw)
In-Reply-To: <20030622091522.M37248@oasis.net.au>
Hi,
you need find duplicates and then you remove them
delete from aap where id not in ( select max(id) from aap b where
aap.keyword = b.keyword );
Germán
Sorry about my english
-----Mensaje original-----
De: pgsql-sql-owner@postgresql.org
[mailto:pgsql-sql-owner@postgresql.org] En nombre de Rudi Starcevic
Enviado el: Domingo, 22 de Junio de 2003 5:15
Para: pgsql-sql@postgresql.org
Asunto: [SQL] Delete duplicates
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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To: pgsql-sql@postgresql.org
Cc: germangutierrezg@entelchile.net
Subject: Re: Delete duplicates
In-Reply-To: <000a01c338ec$b9635d00$eaf1fea9@german>
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