Re: Does Codd's view of a relational database differ from that ofDate& Darwin? [M.Gittens]

On Tue, 07 Jun 2005 17:42:23 +0200, Alexandr Savinov <savinov_at_host.com> wrote:

[snip]

>To say "if NULL means unknown" is the same as to say "if 0 is equal 1"
>or "if empty set is full set". Unknown and null are two different things
>and deserve to have to special designations.
>
>NULL means absence
>UNKNOWN means presence with unknown identity

     What term would you use for the case of it being unknown whether the value exists?

[snip]

Sincerely,

Gene Wirchenko Received on Wed Jun 08 2005 - 12:04:27 CDT