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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Tomas Vondra <tomas.vondra@2ndquadrant.com>
Cc: David Steele <david@pgmasters.net>
Cc: Stephen Frost <sfrost@snowman.net>
Cc: Michael Paquier <michael.paquier@gmail.com>
Cc: Haribabu Kommi <kommi.haribabu@gmail.com>
Cc: pgsql-hackers@postgresql.org <pgsql-hackers@postgresql.org>
Subject: Re: [HACKERS] VACUUM and ANALYZE disagreeing on what reltuples means
Date: Thu, 22 Mar 2018 13:28:52 -0400
Message-ID: <14503.1521739732@sss.pgh.pa.us> (raw)
In-Reply-To: <3b3d8eac-c709-0d25-088e-b98339a1b28a@2ndquadrant.com>
References: <16db4468-edfa-830a-f921-39a50498e77e@2ndquadrant.com>
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Tomas Vondra <tomas.vondra@2ndquadrant.com> writes:
> 0001 fixes this by tracking the number of actually indexed rows in the
> build states, just like in the other index AMs.
> A VACUUM or ANALYZE will fix the estimate, of course, but for tables
> that are not changing very much it may take quite a while. So I think
> this is something we definitely need to back-patch.

Agreed, and done.  I noticed a second bug in contrib/bloom, too: it'd
forget to write out the last index page if that contained only one
tuple, because the new-page code path in bloomBuildCallback failed to
increment the "count" field after clearing it.

> The 0002 part is the main part, unifying the definition of reltuples on
> three main places:

On to this part ...

			regards, tom lane




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  Cc: tgl@sss.pgh.pa.us, tomas.vondra@2ndquadrant.com, david@pgmasters.net, sfrost@snowman.net, michael.paquier@gmail.com, kommi.haribabu@gmail.com
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