[thelist] Foreign Key constraints

Andrew Kamm akamm at demicooper.com
Fri Jun 9 10:42:37 CDT 2006

> You could put a DELETE TRIGGER on your state table, to go through your
> customer table, find any references to the state IDs being deleted and
> set them to NULL. Something like (I haven't tested this):
>   CREATE TRIGGER trNullifyStateReferences ON states FOR DELETE
>   AS
>   UPDATE customers SET customers.state_id = NULL
> WHERE customers.state_id IN (SELECT state_id FROM deleted)

Excellent -- my deadline won't allow for it on this one, but I'll keep this
on file for future projects.


Andrew Kamm

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