Re: keeping last 30 entries of a log table

On Wed, 21 Jun 2006, Ben K. wrote:

> Just for the sake of alternatives -
>
> create sequence cy30 maxvalue 30 cycle;
>
> insert into log values(select generate_series(1,30), 'dummy');
> INSERT 0 30
>
> update log set des='....' where account_id=(select nextval('cy30'));
> UPDATE 1
>
>
> There are details to consider I guess. For example what if an update fails
> and the sequence already advanced... Also, since we cycle the id, for
> sorting, we'll need to add timestamp or something similar.
>

Only problem with this approach is that I need to be able to keep track of the
last 30 items per each account_id...so each account_id will have his last 30
messages in the table.

--
Jeff Frost, Owner <jeff(at)frostconsultingllc(dot)com>
Frost Consulting, LLC http://www.frostconsultingllc.com/
Phone: 650-780-7908 FAX: 650-649-1954