Reply to Unique constraint for the columns does not work when one of values is null.
Posted by Pugi! on 09/14/07 10:55
I have a table with a unique constraint on two integer columns.
Works fine, but one of the two columns can be null and then the
constraint does not work.
1 2 : OK
1 3 : OK
1 2 : error
2 null : OK
2 null : OK -> I want this to result in an error