On Sun, May 11, 2014 at 11:23 PM, Tom Lane <
tgl@sss.pgh.pa.us> wrote:
> I think it's clearly *necessary* to forbid setting data_directory in
> postgresql.auto.conf. The file is defined to be found in the data
> directory, so any such setting is circular logic by definition;
> no good can come of not rejecting it.
>
> We already have a GUC flag bit about disallowing certain variables
> in the config file (though I don't remember if it's enforced or
> just advisory). It seems to me that we'd better invent one for
> disallowing in ALTER SYSTEM, as well.
I introduced a new flag bit (GUC_DISALLOW_IN_AUTO_FILE) to
disallow parameters by Alter System and disallowed data_directory to
be set by Alter System.