| From: | Bruce Momjian <bruce(at)momjian(dot)us> |
|---|---|
| To: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
| Cc: | Volker Grabsch <vog(at)notjusthosting(dot)com>, pgsql-hackers(at)postgresql(dot)org |
| Subject: | Re: Missing optimization when filters are applied after window functions |
| Date: | 2012-05-24 19:55:21 |
| Message-ID: | 20120524195521.GI10306@momjian.us |
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| Lists: | pgsql-hackers |
On Wed, May 16, 2012 at 09:25:13AM -0400, Tom Lane wrote:
> Volker Grabsch <vog(at)notjusthosting(dot)com> writes:
> > I propose the following general optimization: If all window
> > functions are partitioned by the same first field (here: id),
> > then any filter on that field should be executed before
> > WindowAgg.
>
> I'm not sure if that rule is correct in detail, but in any case the
> short answer is that window aggregates are a new feature in Postgres
> and we basically haven't done any optimization work on them yet.
> Feel free to work in that area if it interests you...
Is this a TODO?
--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://enterprisedb.com
+ It's impossible for everything to be true. +
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