Re: Possible to improve query plan?

2011/1/25 Kevin Grittner <Kevin.Grittner@wicourts.gov>:
> Jeremy Palmer <JPalmer@linz.govt.nz> wrote:
>
>> Kevin I've now clustered the table. And the performance did
>> increase quite a bit.
>
> Yeah, that's enough to notice the difference.
>
>> My only question is how often will I need to re-cluster the table,
>> because it comes at quite a cost. The setup I'm running will mean
>> that 10,000 new rows will be inserted, and 2,500 rows will be
>> updated on this table each day.
>
> You're going to see performance drop off as the data fragments.
> You'll need to balance the performance against maintenance
> down-time.  I would guess, though, that if you have a weekly
> maintenance window big enough to handle the CLUSTER, it might be
> worth doing it that often.

Was FILLFACTOR already suggested regarding the INSERT vs UPDATE per day ?

http://www.postgresql.org/docs/9.0/static/sql-altertable.html (and
index too, but they already have a default at 90% for btree)

>
> -Kevin
>
> --
> Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org)
> To make changes to your subscription:
> http://www.postgresql.org/mailpref/pgsql-performance
>



--
Cédric Villemain               2ndQuadrant
http://2ndQuadrant.fr/     PostgreSQL : Expertise, Formation et Support