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Re: Pull up aggregate subquery - Mailing list pgsql-hackers

From Tom Lane
Subject Re: Pull up aggregate subquery
Date
Msg-id 5744.1306335790@sss.pgh.pa.us
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In response to Re: Pull up aggregate subquery  (Hitoshi Harada <umi.tanuki@gmail.com>)
Responses Re: Pull up aggregate subquery  (Hitoshi Harada <umi.tanuki@gmail.com>)
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Hitoshi Harada <umi.tanuki@gmail.com> writes:
> 2011/5/25 Hitoshi Harada <umi.tanuki@gmail.com>:
>> So I'm still
>> thinking which of pulling up and parameterized scan is better.

> After more investigation I came up with third idea, pushing down
> RangeTblEntry to aggregate subquery. This sounds like a crazy idea,

Yes, it sure does.  Won't that typically change the number of rows
produced by the subquery's jointree?  And thus possibly change the
aggregate's result?
        regards, tom lane

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