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Re: Useless memoize path generated for unique join on primary keys - Mailing list pgsql-performance

From David Rowley
Subject Re: Useless memoize path generated for unique join on primary keys
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Msg-id CAApHDvrjwrmnxe__Xhz0NyxKL6d1wW7i=2_p+d5oj2QfmTCnhA@mail.gmail.com
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In response to Re: Useless memoize path generated for unique join on primary keys  (Benjamin Coutu <ben.coutu@zeyos.com>)
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On Wed, 4 May 2022 at 00:21, Benjamin Coutu <ben.coutu@zeyos.com> wrote:
> Thanks David, using extended statistics for both (and only for both) tables solved this problem.

Oh, whoops. I did get that backwards.  The estimate used by the
Memoize costing code is from the outer side of the join, which is the
extdataempty in this case. I don't think the
extdataregular_field_index_stats will do anything. It'll be the ones
you added on extdataempty that are making it work.

> BTW, thank you for all your work on performance in recent releases.

Thanks for the feedback :)

David

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