Re: Not Null Constraint vs Query Planning

On 02/03/2020 18:09, Don Seiler wrote:
> The REAL reason for this is that I'm wondering if I created a NOT NULL
> check constraint with "NOT VALID" would that then NOT be considered in such
> a "short-circuit" case until I ran the VALIDATE CONSTRAINT on it? Perhaps I
> should have just asked this in its own thread but I started diving into the
> query plan thing.

You cannot do this because NOT NULL isn't a real constraint (meaning it
does not appear in pg_constraint).  There have been several attempts to
make it a real constraint over the years but so far nothing has come of
them