Re: How to delete the oldest X number of rows? - Mailing list pgsql-novice

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
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Andreas Kretschmer    (Kontakt: siehe Header)
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