| From: | Daniel Farina <drfarina(at)acm(dot)org> |
|---|---|
| To: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
| Cc: | Hitoshi Harada <umi(dot)tanuki(at)gmail(dot)com>, pgsql-hackers(at)postgresql(dot)org |
| Subject: | Re: Windowing Qual Pushdown |
| Date: | 2010-03-23 16:46:43 |
| Message-ID: | 7b97c5a41003230946x6338583ar882c5c0df097976a@mail.gmail.com |
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| Lists: | pgsql-hackers |
On Tue, Mar 23, 2010 at 8:23 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> The real question is what benefit you expect to get. If the filter
> condition can't be pushed below the window functions (which AFAICS
Even on the partition key?
Right now if you define a view with a windowing + PARTITION BY clause
in it and people write a lot of queries to interrogate one partition
or the other, you end up computing results for the entire relation,
and then filtering all but one partition out, in my understanding.
Since it seems on the surface there is no context sensitivity(?)
between partitions in this kind of a case it would seem a qual
pushdown on the partition key would help rather intensely.
fdr
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