Re: Neither column can be NULL if the column is part of the combination of primary key columns?

>
> To allow *col2* to be NULL and make record combination (col1, col2)
> unique, I should setup
> unique (col1, col2) ?
>
> Thanks,
> Emi
>

no, you must create a partial unique index...

create unique index indice_col2 on table(col1, col2) where col2 is not null;

--
Atentamente,
Jaime Casanova
(DBA: DataBase Aniquilator ;)