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Re: How to change order sort of table in HashJoin - Mailing list pgsql-hackers

From Tom Lane
Subject Re: How to change order sort of table in HashJoin
Date
Msg-id 18388.1479659979@sss.pgh.pa.us
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In response to Re: How to change order sort of table in HashJoin  (Man <man.trieu@gmail.com>)
Responses Re: How to change order sort of table in HashJoin  (Man <man.trieu@gmail.com>)
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Man <man.trieu@gmail.com> writes:
> Additional information.
> In 9.6 the second table (lesser tuple) was choosen (the same testdata).
> There are something (cost estimation?) different  in previous versions.

I'd bet on different statistics in the two installations (either you
forgot to ANALYZE, or the random sample came up quite a bit different).
And I'm a little suspicious that these tests weren't all done with the
same work_mem setting.

            regards, tom lane

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