>>>Hi,
>>>
>>>I am still getting a "conflict" message when trying to create a foreign key constraint. I checked that the table with the foreign key has only those entries in the key column that are present in the unique column of the parent table. The only thing is that the foreign key table has some records with empty value in the foreign key field. Could this be the problem? (I thought that empty column records are not counted in the constraint but maybe I am mistaken).
>>>
>>>TIA.
>>
>>You can add NOCHECK when creating a constraint.
>
>I know. But I wanted to see what was causing the conflict.

Well, obviously empty values are not allowed (and NULLs are allowed).