| Subject | Re: [firebird-support] unique constraint on a pair, one NOT NULL, one NULL |
|---|---|
| Author | Ann W. Harrison |
| Post date | 2009-05-06T15:06:48Z |
Ivan Prenosil wrote:
think it does) so two rows like this:
c1 c2
===== =====
ABCD <NULL>
ABCD <NULL>
are allowed.
Cheers,
Ann
>Yes, but that constraint follows the SQL rules (at least I
> Firebird _does_ allow Unique Constraint on nullable columns.
> (But of course it does not allow PK Constraint).
>
think it does) so two rows like this:
c1 c2
===== =====
ABCD <NULL>
ABCD <NULL>
are allowed.
Cheers,
Ann