Michael Paquier <michael@paquier.xyz> writes:
> Is there a reason why we don't just use islower() or is that just to
> get something entirely local independent?
islower() and related functions are not to be trusted for this
purpose. They will certainly give locale-dependent results,
and they might give entirely wrong ones if there's any inconsistency
between the database encoding and what libc thinks the locale is.
regards, tom lane