Feedback-ID: ia2694551:Fastmail
Date: Tue, 13 Aug 2024 14:18:58 -0400
From: Alvaro Herrera from 2ndQuadrant <alvherre@alvh.no-ip.org>
To: Kuntal Ghosh <kuntalghosh.2007@gmail.com>
Cc: Junwang Zhao <zhjwpku@gmail.com>, Tender Wang <tndrwang@gmail.com>,
	pgsql-bugs@lists.postgresql.org
Subject: Re: BUG #18559: Crash after detaching a partition concurrently from
 another session
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On 2024-Aug-13, Kuntal Ghosh wrote:

> That means - after getting the live partitions from
> prune_append_rel_partitions(), by the time the code tries to lock a
> child, it's already dropped.

Right.

> However, similar check is not there in expand_partitioned_rtentry().
> Introducing the same check will fix the issue. But, I don't know how
> it affects the pruning part as this partition couldn't be pruned
> earlier and that's why we're opening the child partition.

Hmm, we could just remove the partition from the set of live partitions
-- then it should behave the same as if the partition had been pruned.
Something like the attached, perhaps.

-- 
Álvaro Herrera         PostgreSQL Developer  —  https://www.EnterpriseDB.com/
"In fact, the basic problem with Perl 5's subroutines is that they're not
crufty enough, so the cruft leaks out into user-defined code instead, by
the Conservation of Cruft Principle."  (Larry Wall, Apocalypse 6)

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