Subject: Re: [PATCH] Stop ALTER SYSTEM from making bad assumptions
To: Tom Lane <tgl@sss.pgh.pa.us>, Andres Freund <andres@anarazel.de>
Cc: Stephen Frost <sfrost@snowman.net>, Amit Kapila
 <amit.kapila16@gmail.com>, Robert Haas <robertmhaas@gmail.com>,
 Tomas Vondra <tomas.vondra@2ndquadrant.com>,
 "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
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From: Ian Barwick <ian.barwick@2ndquadrant.com>
Message-ID: <1212f308-8140-32c8-2b5c-110f0f352f2d@2ndquadrant.com>
Date: Sat, 3 Aug 2019 08:18:00 +0900
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On 8/3/19 8:09 AM, Tom Lane wrote:
> I wrote:
>> Andres Freund <andres@anarazel.de> writes:
>>> I think a commandline tool to perform the equivalent of ALTER SYSTEM on
>>> a shutdown cluster would be a great tool.
> 
>> Perhaps, but ...
> 
>>> Obviously this is widely out of scope for v12.
> 
>> ... this.
> 
> Although, there's always
> 
> echo "alter system set work_mem = 4242;" | postgres --single
> 
> Maybe we could recommend that to tools that need to do
> potentially-repetitive modifications?

The slight problem with that, particularly with the use-case
I am concerned with (writing replication configuration), is:

     [2019-08-03 08:14:21 JST]    FATAL:  0A000: standby mode is not supported by single-user servers

(I may be missing something obvious of course)


Regards

Ian Barwick

-- 
  Ian Barwick                   https://www.2ndQuadrant.com/
  PostgreSQL Development, 24x7 Support, Training & Services