From: Tomasz Myrta <jasiek@klaster.net>
To: Dan Langille <dan@langille.org>
To: pgsql-sql@postgresql.org
Subject: Re: DELETE FROM t WHERE EXISTS
Date: Fri, 28 Feb 2003 21:28:27 +0800
Message-ID: <20030228212827.M96860@klaster.net> (raw)
In-Reply-To: <3E5F530B.1649.424D34C1@localhost>
References: <3E5F530B.1649.424D34C1@localhost>
> Hi folks,
>
> I wanted to delete "old" rows from a table. These are the rows I
> want to keep:
>
> SELECT *
> FROM clp
> ORDER BY commit_date
> LIMIT 100
>
> So I tried this:
>
> DELETE FROM clp
> WHERE NOT EXISTS (
> SELECT *
> FROM clp
> ORDER BY commit_date
> LIMIT 100);
>
> Uhh uhh, nothing deleted. I don't understand why.
>
> OK, I can do this instead:
>
> DELETE from clp
> where commit_log_id NOT in (
> SELECT commit_log_id
> FROM clp
> ORDER BY commit_date
> LIMIT 100);
>
> Can you think of a better way?
delete from clp where commit_date < (select commit_date from clp order by
commit_date limit 1 offset 100);
Regards,
Tomasz Myrta
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To: pgsql-sql@postgresql.org
Cc: jasiek@klaster.net, dan@langille.org
Subject: Re: DELETE FROM t WHERE EXISTS
In-Reply-To: <20030228212827.M96860@klaster.net>
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