On Thu, Oct 6, 2011 at 4:16 PM, Florian Pflug <f...@phlo.org> wrote: > Sure, but there are still a lot of cases where the database could deduce > (quite easily) that a result column cannot be null. Other databases do > that - for example, I believe to remember that Microsoft SQL Server preserves > NOT NULL constraints if you do > > CREATE TABLE bar AS SELECT * from foo; > > So the question makes perfect sense, and the answer is: No, postgres currently > doesn't support that, i.e. doesn't deduce the nullability of result columns, > not even in the simplest cases.
hm, good point. not sure how it's useful though. I suppose an application could leverage that for validation purposes, but that's a stretch I think. merlin -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers