Re: Speedier count(*)

On Thu, 11 Aug 2005, Tino Wildenhain wrote:

> Am Donnerstag, den 11.08.2005, 00:40 -0400 schrieb Mark Cotner:
> > Here's a trigger I wrote to perform essentially the same purpose.  The nice
> > thing about this is it keeps the number up to date for you, but you do incur
> > slight overhead.
> ...
> >
> > CREATE TRIGGER del_rowcount_tr BEFORE DELETE ON test FOR EACH ROW EXECUTE
> >    PROCEDURE del_rowcount();
> > CREATE TRIGGER add_rowcount_tr BEFORE INSERT ON test FOR EACH ROW EXECUTE
> >    PROCEDURE add_rowcount();
> >
> > INSERT INTO rowcount (tablename) VALUES ('test');
> ...
>
> beware of problems with concurrency and even what happens
> if transactions roll back. Maybe you can "fix" it a bit
> by regulary correcting the count via cronjob or so.

What problems? MVCC takes care of this.

Gavin