Re: Can FK be nullable/optional by design?

net__space_at_hotmail.com (Andy) writes:

> General statement: FK should not be nullabe to avoid orphans in DB.

I don't see the reasoning behind this statement. Any column that references keys to another table should be explicitly specified as such to avoid orphans.

If that column may sometimes be unknown/unspecified for perfectly valid records, I see no reason not to make it nullable.

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