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Date: Wed, 23 Jun 2010 15:14:41 -0400
Message-ID: <AANLkTikJ2Z8BInqKg5k9hnSeT6hScJGQ7wr-4mW_yNjR@mail.gmail.com>
Subject: Re: hot standby documentation
From: Robert Haas <robertmhaas@gmail.com>
To: Simon Riggs <simon@2ndquadrant.com>
Cc: Joshua Tolley <eggyknap@gmail.com>, pgsql-docs <pgsql-docs@postgresql.org>
Content-Type: text/plain; charset=ISO-8859-1

On Wed, Jun 23, 2010 at 3:05 PM, Robert Haas <robertmhaas@gmail.com> wrote:
>> We could also allow SELECT ... FOR SHARE during Hot Standby, simply by
>> making it same as normal SELECT, without any ill effects.
>
> True.

Actually, wait a minute.  Why wouldn't we need to lock the tuples on
the standby just as we do on the primary?  Sure, there can't be
another user transaction modifying those tuples, but WAL replay could
still modify them.

Anyhow, I think that's beside the point.  The documentation just says
what Hot Standby does, not what it might do in a future release.  And
I don't think this patch changes that very much at all.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise Postgres Company