Re: How to delete the oldest X number of rows?

Thank you! That works beautifully!

John

-----Original Message-----
From: pgsql-novice-owner(at)postgresql(dot)org
[mailto:pgsql-novice-owner(at)postgresql(dot)org] On Behalf Of A. Kretschmer
Sent: Monday, December 12, 2005 11:47 AM
To: pgsql-novice(at)postgresql(dot)org
Subject: Re: [NOVICE] How to delete the oldest X number of rows?
Importance: High

am 12.12.2005, um 11:29:58 -0500 mailte John Roberts folgendes:
> Hi,
>
> I have a table that logs the performance of a system. I get an entry in
> this table each time the system does something.
>
> I want to keep the last 50,000 rows in the table. I'd like to run a cron
> job every 5 minutes that will delete all rows > 50,000, oldest first.
> What's the most efficient way to do this query/delete?
>
> DELETE FROM log WHERE timestamp < ????

Something like:

select timestamp from log order by timestamp limit 1 offset 49999;

to get the oldest timestamp to keep and delete the early rows?

*untestet*

delete from fol where timestamp < (select timestamp from log order by
timestamp limit 1 offset 49999);

HTH, Andreas
--
Andreas Kretschmer (Kontakt: siehe Header)
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