Re: SET NULL / SET NOT NULL

>   ALTER TABLE tab ALTER COLUMN col DROP NOT NULL
>
> which does not seem particularly good; preserving the syntax from
table
> creation has to be TWTG. Do we really allow:
>
> CREATE TABLE FOO(BAR INT NULL)

Certainly does.  I depend on that ability to override the standard
NULL / NOT NULL constraint that the domain may have to account for the
exception to the rule.

Actually, is that proper?  Equally easy to disallow overrides, but
(since the books I have don't say) it seemed useful for people with
funny circumstances (like wanting to log a miss as well a hit).