Hi,
On Thu, 2008-08-28 at 14:20 -0400, Tom Lane wrote:
> > If the table is in fact empty, why is it a bad idea to let the
> > statistics reflect that?
>
> I think that this thinking is at least partially obsolete now that
> autovacuum/autoanalyze and plan invalidation are in place. It used to
> be that if you truncated a table and then filled it again, any cached
> plans that were made while the table was really small would tend to
> suck when used with the re-filled table. But now, autovac will launch
> (at least) an ANALYZE against any table that's grown materially, and
> the commit of the new analyze stats will result in invalidating any
> cached plans. So the system should be capable of auto-tuning its
> plans to changes in table size ... not instantaneously of course, but
> then you can't fill a big table instantaneously either.
Good point.
--
Devrim GÜNDÜZ, RHCE
devrim~gunduz.org, devrim~PostgreSQL.org, devrim.gunduz~linux.org.tr
http://www.gunduz.org