Peter Eisentraut <peter_e(at)gmx(dot)net> writes:
> Moreover, the unset state shouldn't exist at all. No parameter can behave
> reasonably if unset behaved differently from an empty string. Explicitly
> assigning an unset state doesn't work. So it seems that for all external
> communication, an unset string parameter should simply display the empty
> string.
I wouldn't object to that, but my recollection is that that was once the
behavior, and somebody insisted it was bad.
regards, tom lane