Received: from malur.postgresql.org ([217.196.149.56])
	by arkaria.postgresql.org with esmtps
 (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256)
	(Exim 4.92)
	(envelope-from <pgsql-hackers-owner+archive@lists.postgresql.org>)
	id 1kzni1-0007SD-18
	for pgsql-hackers@arkaria.postgresql.org; Wed, 13 Jan 2021 21:29:41 +0000
Received: from localhost ([127.0.0.1] helo=malur.postgresql.org)
	by malur.postgresql.org with esmtp (Exim 4.92)
	(envelope-from <pgsql-hackers-owner+archive@lists.postgresql.org>)
	id 1kznhy-00009e-U3
	for pgsql-hackers@arkaria.postgresql.org; Wed, 13 Jan 2021 21:29:38 +0000
Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29])
	by malur.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256)
	(Exim 4.92)
	(envelope-from <tgl@sss.pgh.pa.us>)
	id 1kznhy-00009X-N8
	for pgsql-hackers@lists.postgresql.org; Wed, 13 Jan 2021 21:29:38 +0000
Received: from sss.pgh.pa.us ([66.207.139.130])
	by magus.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256)
	(Exim 4.92)
	(envelope-from <tgl@sss.pgh.pa.us>)
	id 1kznhw-0005p7-Pj
	for pgsql-hackers@lists.postgresql.org; Wed, 13 Jan 2021 21:29:38 +0000
Received: from sss1.sss.pgh.pa.us (localhost [127.0.0.1])
	by sss.pgh.pa.us (8.15.2/8.15.2) with ESMTP id 10DLTVnj1337020;
	Wed, 13 Jan 2021 16:29:31 -0500
From: Tom Lane <tgl@sss.pgh.pa.us>
To: Alvaro Herrera <alvherre@alvh.no-ip.org>
cc: James Coleman <jtc331@gmail.com>, Michael Paquier <michael@paquier.xyz>,
        David Johnston <david.g.johnston@gmail.com>,
        PostgreSQL Developers <pgsql-hackers@lists.postgresql.org>,
        Andres Freund <andres@anarazel.de>
Subject: Re: [DOC] Document concurrent index builds waiting on each other
In-reply-to: <20210113211604.GA16584@alvherre.pgsql>
References: <20210113211604.GA16584@alvherre.pgsql>
Comments: In-reply-to Alvaro Herrera <alvherre@alvh.no-ip.org>
	message dated "Wed, 13 Jan 2021 18:16:04 -0300"
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-ID: <1337018.1610573371.1@sss.pgh.pa.us>
Content-Transfer-Encoding: quoted-printable
Date: Wed, 13 Jan 2021 16:29:31 -0500
Message-ID: <1337019.1610573371@sss.pgh.pa.us>
List-Id: <pgsql-hackers.lists.postgresql.org>
List-Help: <https://lists.postgresql.org/manage/>
List-Subscribe: <https://lists.postgresql.org/manage/>
List-Post: <mailto:pgsql-hackers@lists.postgresql.org>
List-Owner: <mailto:pgsql-hackers-owner@lists.postgresql.org>
List-Archive: <https://www.postgresql.org/list/pgsql-hackers>
Precedence: bulk

Alvaro Herrera <alvherre@alvh.no-ip.org> writes:
> On 2021-Jan-13, James Coleman wrote:
>>>> This is true.  So I propose
>>>> Like any long-running transaction, <command>REINDEX</command> can
>>>> affect which tuples can be removed by concurrent <command>VACUUM</com=
mand>
>>>> on any table.

>> Looks like what got committed is "REINDEX on a table" not "on any",
>> but I'm not sure that matters too much.

> Ouch.  The difference seems slight enough that it doesn't matter; is it
> ungrammatical?

I'd personally have written "on other tables" or "on another table",
or left out that clause altogether and just said "concurrent
<command>VACUUM</command>".  I'm not sure it's ungrammatical exactly,
but the antecedent of "a table" is a bit unclear; people might
wonder if it means the table being reindexed.

			regards, tom lane