From: Tom Lane <tgl@sss.pgh.pa.us>
To: zyake.mk4@gmail.com
cc: pgsql-docs@lists.postgresql.org
Subject: Re: Required locks for ANALYZE
In-reply-to: <156628723253.1296.7377373462603881976@wrigleys.postgresql.org>
References: <156628723253.1296.7377373462603881976@wrigleys.postgresql.org>
Comments: In-reply-to PG Doc comments form <noreply@postgresql.org>
	message dated "Tue, 20 Aug 2019 07:47:12 -0000"
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Date: Tue, 20 Aug 2019 10:12:24 -0400
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PG Doc comments form <noreply@postgresql.org> writes:
> Therefore, in my opinion, the below paragraph should be amended as below.

> * Before
> -----
> ANALYZE requires only a read lock on the target table, so it can run in
> parallel with other activity on the table.
> -----

> * After
> -----
> ANALYZE requires only a SHARE UPDATE EXCLUSIVE lock on the target table, so
> it can run in parallel with queries requiring ACCESS SHARE/ROW SHARE/ROW
> EXCLUSIVE locks such as SELECT, UPDATE, DELETE, INSERT on the table.
> -----

This does not really seem like an improvement.  The second formulation is
pedantically correct, but also unintelligible.

Maybe we could make it say "run in parallel with non-DDL activity" ?

			regards, tom lane