"David G. Johnston" <david.g.johnston@gmail.com> writes:
> This is a bit hard to reason about given that our implementation of
> inheritance is non-standard.
Yeah, that's a fairly key point. We've solved those problems with
respect to inherited CHECK constraints, and it seems like what we
ought to do with NOT NULL is make it work the same as CHECK, rather
than invent some new concepts.
regards, tom lane