Message-ID: <5C7FC516.10100@lab.ntt.co.jp>
Date: Wed, 06 Mar 2019 22:03:18 +0900
From: Etsuro Fujita <fujita.etsuro@lab.ntt.co.jp>
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Subject: Re: Problems with plan estimates in postgres_fdw
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To: Jeff Janes <jeff.janes@gmail.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Andrew Gierth <andrew@tao11.riddles.org.uk>,
        pgsql-hackers <pgsql-hackers@postgresql.org>
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(2019/02/22 17:17), Etsuro Fujita wrote:
> (2019/02/21 6:19), Jeff Janes wrote:

>> With your tweaks, I'm still not seeing the ORDER-less LIMIT get pushed
>> down when using use_remote_estimate in a simple test case, either with
>> this set of patches, nor in the V4 set. However, without
>> use_remote_estimate, the LIMIT is now getting pushed with these patches
>> when it does not in HEAD.
>
> Good catch! I think the root cause of that is: when using
> use_remote_estimate, remote estimates obtained through remote EXPLAIN
> are rounded off to two decimal places, which I completely overlooked.
> Will fix. I think I can post a new version early next week.

Done.  Please see [1].  Sorry for the delay.

Best regards,
Etsuro Fujita

[1] https://www.postgresql.org/message-id/5C7FC458.4020400%40lab.ntt.co.jp