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Howdy!

NULL as used in relational databases still carries semantic ambiguity.

It could indicate that the value is absent, or it could indicate that the value is unknown. Or it could mean either. If I recall correctly, Codd called for multiple flavors of NULL.

yours,
Michael

In reply to Re^2: "undef" is not NULL and what to do about it by herveus
in thread "undef" is not NULL and what to do about it by Ovid

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