From: Tom Lane <tgl@sss.pgh.pa.us>
To: Peter Geoghegan <pg@bowt.ie>
cc: Robert Haas <robertmhaas@gmail.com>,
        Mark Dilger <mark.dilger@enterprisedb.com>,
        Noah Misch <noah@leadboat.com>, Thomas Munro <thomas.munro@gmail.com>,
        "Andrey M. Borodin" <x4mmm@yandex-team.ru>,
        Stephen Frost <sfrost@snowman.net>,
        Michael Paquier <michael@paquier.xyz>, Amul Sul <sulamul@gmail.com>,
        Dilip Kumar <dilipbalaut@gmail.com>,
        Andres Freund <andres@anarazel.de>,
        PostgreSQL-development <pgsql-hackers@postgresql.org>
Subject: Re: pg_amcheck contrib application
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Comments: In-reply-to Peter Geoghegan <pg@bowt.ie>
	message dated "Tue, 23 Mar 2021 12:41:54 -0700"
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Date: Tue, 23 Mar 2021 15:44:48 -0400
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Peter Geoghegan <pg@bowt.ie> writes:
> That being said, I should make _bt_lock_subtree_parent() return false
> and back out of page deletion without raising an error in the case
> where we really cannot locate a valid downlink. We really ought to
> soldier on when that happens, since we'll do that for a bunch of other
> reasons already. I believe that the only reason we throw an error
> today is for parity with the page split case (the main
> _bt_getstackbuf() call). But this isn't the same situation at all --
> this is VACUUM.

> I will make this change to HEAD soon, barring objections.

+1.  Not deleting the upper page seems better than the alternatives.

			regards, tom lane