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

Fujii Masao <masao.fujii@gmail.com> writes:
> Do we really need to store the settings in a system table?
> Since WAL would be generated when storing the settings
> in a system table, this approach seems to prevent us from
> changing the settings in the standby.

That's a really good point: if we try to move all GUCs into a system
table, there's no way for a standby to have different values; and for
some of them different values are *necessary*.

I think that shoots down this line of thought entirely.  Can we go
back to the plain "write a file" approach now?  I think a "SET
PERSISTENT" command that's disallowed in transaction blocks and just
writes the file immediately is perfectly sensible.
        regards, tom lane