Re: Strange explain on partitioned tables - Mailing list pgsql-performance

From Joshua D. Drake
Subject Re: Strange explain on partitioned tables
Date
Msg-id 1279923370.9866.37.camel@jd-desktop.unknown.charter.com
Whole thread Raw
In response to Re: Strange explain on partitioned tables  (Gerald Fontenay <gvfontenay@lbl.gov>)
Responses Re: Strange explain on partitioned tables
Re: Strange explain on partitioned tables
List pgsql-performance
On Fri, 2010-07-23 at 15:03 -0700, Gerald Fontenay wrote:
> > The PostgreSQL partitioning system is aimed to support perhaps a
> > hundred inherited tables.  You can expect to get poor performance on
> > queries if you create 1000 of them.
>
> Hi,
>
> Why is that you would expect poor performance for say 1000 or more? I
> have a ~1000 inherited tables and I don't see any significant slowdowns.
> I only ever access a single inherited table at a time though in this
> situation. I suppose I am using inheritance only for organization in
> this case...

It is variable based on workload and as I recall has to do with the
planning time. As the number of children increases, so does the planning
time.

Joshua D. Drake


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