Re: Can FK be nullable/optional by design?

From: Bruce Lewis <>
Date: 01 Dec 2003 09:35:24 -0500
Message-ID: <> (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.

"Notwithstanding fervent argument that patent protection is essential
 for the growth of the software industry, commentators have noted
 that `this industry is growing by leaps and bounds without it.'"
        -- US Supreme Court Justice John Paul Stevens, March 3, 1981.
Received on Mon Dec 01 2003 - 15:35:24 CET

Original text of this message