Re: [PATCH] Stop ALTER SYSTEM from making bad assumptions

On Mon, Jun 17, 2019 at 8:20 PM Ian Barwick <ian(dot)barwick(at)2ndquadrant(dot)com> wrote:
> On 6/15/19 1:08 AM, Stephen Frost wrote:
> > * Amit Kapila (amit(dot)kapila16(at)gmail(dot)com) wrote:
> >> Right. I think if possible, it should use existing infrastructure to
> >> write to postgresql.auto.conf rather than inventing a new way to
> >> change it. Apart from this issue, if we support multiple ways to edit
> >> postgresql.auto.conf, we might end up with more problems like this in
> >> the future where one system is not aware of the way file being edited
> >> by another system.
> >
> > I agere that there should have been some effort put into making the way
> > ALTER SYSTEM is modified be consistent between the backend and utilities
> > like pg_basebackup (which would also help third party tools understand
> > how a non-backend application should be modifying the file).
>
> Did you mean to say "the way postgresql.auto.conf is modified"?
>

Yes, that is what we are discussing here. I think what we can do here
is to extract the functionality to set the parameter in .auto.conf
from AlterSystemSetConfigFile and expose it via a function that takes
(option_name, value) as a parameter. Then we can expose it via some
SQL function like set_auto_config (similar to what we have now for
set_config/set_config_by_name). I think if we have something like
that then pg_basebackup or any other utility can use it in a
consistent way.

--
With Regards,
Amit Kapila.
EnterpriseDB: http://www.enterprisedb.com