Erki Eessaar <erki.eessaar@taltech.ee> writes:
> My question is - is all of this the intended behaviour by the implementers?
Yes, I'd say so. If you are expecting that the is_updatable flag
will check to see if the behavior provided by the view's rules
corresponds to something that a human would call a corresponding
update of the view's output, you're out of luck. There's a little
issue called the halting problem. So the actual check just looks
to see if there's unconditional DO INSTEAD rules of the appropriate
types, and doesn't probe into what those rules do.
regards, tom lane