Subject | RE: [firebird-support] FK's and NULL |
---|---|
Author | Daniel Jimenez |
Post date | 2004-10-28T02:43:57Z |
> Even if there is a parent key that is NULL (which is allowedHi Helen
> on one row in the parent table if the referenced key is a
> UNIQUE constraint), the nulled child rows still have no
> parent, since (NULL==NULL) can never be true.
>
> ./heLen
>
Is it "legal" to define a table which contains FK's and these FK fields
accept NULL? (the FK's are not part of the PK).
As I am getting no errors from FB when I do this, as well as having unique
constraints for the FK fields. I have also defined FK_Constraints so that on
delete and update the result is cascade.
Thanks
danieL
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