Re: Missing Information & Empty Sets.
Date: Tue, 2 Sep 2003 21:21:56 -0400
Message-ID: <kOc5b.407$dR2.42576018_at_mantis.golden.net>
"byrmol" <member27348_at_dbforums.com> wrote in message
news:3321409.1062542731_at_dbforums.com...
>
> Thanks Bob for succint reply..
>
> I added harsh because I see some atrocious ad hominem attacks in
> this forum...
>
> In rugby terms.. Play the Ball not the man....
>
> In reference to question 1..
>
> If we extend every Domain to be a set domain would this allow us to use
> an empty set as the Missing Information marker?
>
> ie.. The INT Domain now becomes this {{1}, {2}...{n}}
>
> instead of {1,2 .....n}
The INT domain would become {{},{0],{0,1},{0,2}...{n,n,n,n,n...}} if we arbitrarily allow a set of INT where we now allow INT. It does not seem like a sufficiently cautious proposal to me.
Relation-valued attributes already allow us to represent optional data as a constrained set where we can enforce a maximum cardinality of 1 by specifying a nullary key. Received on Wed Sep 03 2003 - 03:21:56 CEST