BTW, I should have mentioned that partitioning is a very new feature and
that folks probably would like to know about shortcommings you find
while using it.
On Thu, May 04, 2006 at 11:40:51AM -0700, Sriram Dandapani wrote:
> Thanks...looks like partitioning will help.
>
> -----Original Message-----
> From: Jim Nasby [mailto:jnasby@pervasive.com]
> Sent: Thursday, May 04, 2006 11:37 AM
> To: Sriram Dandapani
> Cc: pgsql-admin@postgresql.org
> Subject: RE: [ADMIN] Tale partitioning
>
> Please include the mailing list in your replies so others can provide
> input.
>
> > From: Sriram Dandapani [mailto:sdandapani@counterpane.com]
> > Most of our reports use a order by limit X...The rowcount in
> > some tables
> > are > 200 million. (and the table size is about 50-100gb)
> >
> > Does the fact that constraint_exclusion doesn't deal with order by
> > /limit
> > makes partitioning an unwise choice.
>
> Well, in a worst-case scenario, partitioning will perform no worse than
> if you had one giant table. So it's not hurting you, it may just not be
> helping you.
>
> > What if the main query does just an order by and an outer query wraps
> > the inner query with a limit..
>
> It all depends on if the order-by code is partitioning aware, and I'm
> not sure that it is. But if you index on the appropriate column it
> should hopefully make use of that...
>
> > I am trying to figure out if I should use partitioning or not (my goal
> > is two-fold..purge lots of data in aged tables and make queries
> > partition-aware)
>
> Well, reason #1 sounds like plenty of justification for using
> partitioning to me.
--
Jim C. Nasby, Sr. Engineering Consultant jnasby@pervasive.com
Pervasive Software http://pervasive.com work: 512-231-6117
vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461