All columns of a primary key constraint are, by definition, not null. One
option is to define a unique index on those columns instead of a primary key
constraint. A unique index does accept nulls.
Tong Zhai wrote in message ...
>Hi, all:
> we are setting up a db, one of the table is works_on, and the primary key
>for that table are composite of project_number and Employee_ssn, so by
>definition they can't be null, but if I do want to insert a record with
>null project_number, how can I do that ?
>
>tong.
>
>
Received on Thu Mar 05 1998 - 00:00:00 CST
