Re: Proposal for Allow postgresql.conf values to be changed via SQL

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Magnus Hagander <magnus@hagander.net>, Amit Kapila <amit.kapila@huawei.com>, Josh Berkus <josh@agliodbs.com>, Christopher Browne <cbbrowne@gmail.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2012-11-07T18:58:13Z
Lists: pgsql-hackers
Robert Haas <robertmhaas@gmail.com> writes:
> On Wed, Nov 7, 2012 at 12:29 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> ... we don't normally read the config file within-commands,
>> and there are both semantic and implementation problems to overcome
>> if you want to do so.

> Why would you need to?  It seems to me that we ought to be able to
> rewrite a machine-generated configuration file without loading those
> values into the current session.

Well, Magnus' proposed implementation supposed that the existing values
*have* been loaded into the current session.  I agree that with some
locking and yet more code you could implement it without that.  But this
still doesn't seem to offer any detectable benefit over value-per-file.

			regards, tom lane