From: Tom Lane <tgl@sss.pgh.pa.us>
To: Julien Rouhaud <rjuju123@gmail.com>
cc: Thomas Munro <thomas.munro@gmail.com>, Marc Cousin <cousinmarc@gmail.com>,
        Alexander Korotkov <a.korotkov@postgrespro.ru>,
        Tomas Vondra <tomas.vondra@2ndquadrant.com>,
        Nikita Glukhov <n.gluhov@postgrespro.ru>,
        PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: Avoid full GIN index scan when possible
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Comments: In-reply-to Julien Rouhaud <rjuju123@gmail.com>
	message dated "Thu, 01 Aug 2019 12:13:24 +0200"
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Date: Thu, 01 Aug 2019 10:37:06 -0400
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Julien Rouhaud <rjuju123@gmail.com> writes:
> Attached v4 that should address all comments.

Eyeing this a bit further ... doesn't scanPendingInsert also need
to honor so->forcedRecheck?  Something along the lines of

-			tbm_add_tuples(tbm, &pos.item, 1, recheck);
+			tbm_add_tuples(tbm, &pos.item, 1, recheck | so->forcedRecheck);

at line 1837?  (Obviously, there's more than one way you could
write that.)

I'm also not exactly satisfied with the new comments --- they aren't
conveying much, and the XXX in one of them is confusing; does that
mean you're unsure that the comment is correct?

The added test case seems a bit unsatisfying as well, in that it
fails to retrieve any rows.  It's not very clear what it's
trying to test.

			regards, tom lane