D2K, optional foreign key on intersection tables?

Hi,

[Quoted] I have a many to many relationship between two entities (FIRST with PK of FIRST_KEY and SECOND with a PK of SECOND_KEY).

I want the intersection table generated to support this relationship to have an optional foreign key to support the SECOND key.

In other words, I want the following to appear FIRST
        FIRST_KEY NOT NULL
SECOND
        SECOND_KEY NOT NULL
FIRSTS_SECONDS

        FIRST_KEY NOT NULL
        SECOND_KEY NULL

so that an entry in FIRSTS_SECONDS if not null must reference a value in SECONDS. This is easy in standard Oracle, but I don't seem to be able to get D2K to generate the required intersection table from the ERD? I've tried making the relationships optional...

Does what I'm attempting make sense? The intersection table will eventually have all the attributes filled and must be valid but during the 'load' process the details of SECOND are unknown.

Any ideas?

Andy

-- 
Andy Hardy
Senior IT Systems Engineer
Cegelec AEG
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