"Matthew T. O'Connor" <matthew(at)zeut(dot)net> writes:
> What I wanted to do was have GUC prevent autovacuum = true
> when the stats collector is not enabled, reguardless of what is in
> postgresql.conf.
GUC can't do that, but I think you can just hack the boolean variable
during startup --- compare what pgstat.c does with
enable_stats_collector. (Not very clean, but I think it is okay within
the context of postmaster start.)
regards, tom lane