Subject RE: [firebird-support] FK's and NULL
Author Daniel Jimenez
> Even if there is a parent key that is NULL (which is allowed
> 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
Hi 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.



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