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Null Foreign Key

I'm having an argument with an incumbent self-taught programmer that
it is OK to use null foreign keys in database design.

My take is the whole point of a foreign key is that it's not supposed
to be optional, it's very definition is it's a necessary link to the
parent table and part of the definition. If it's optional it shouldn't
be part of the definition of a table and should be in a linking table

Jul 20 '05
10 42432
Erland Sommarskog <so****@algonet .se> wrote:
In the end, if you really want to know which of two alternatives that
are best from performance, you have to benchmark them.

Agreed. Amen to that.
Jul 20 '05 #11

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