Re: allowed user/db variables

Andreas Pflug <Andreas(dot)Pflug(at)web(dot)de> writes:
> I wonder if there's a way to read all allowed user/database variables
> that can be set/reset.
> I'd like to have this self-configured in pgAdmin3 instead of hard-coded.

Look at SHOW ALL, maybe? Or the pg_settings system view?

If you're willing to think about a solution that would only exist
starting in 7.4 --- some of my cohorts at Red Hat are about to submit
patches that create a separate "pg_guc" executable that contains
another copy of the backend's GUC variable table, and can be used to
obtain the set of known variables, their wired-in default values, min
and max values, etc. So you could imagine executing this program to
get the info. However, this would only work on the machine where the
stuff is installed, not necessarily on a remote client, so maybe it
wouldn't help pgAdmin.

If anyone's wondering why the RH guys want such an executable instead
of adding functionality to SHOW, it's because they want to be able to
get the info even when the postmaster isn't running; it's for a tool
that will help people set up postgresql.conf, so it seems essential that
the knowledge be available before starting the postmaster.

It occurs to me that we could consider adding columns to pg_settings
to make more info available to remote clients, too. The current value
of a setting is far from its only interesting property ...

regards, tom lane