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Re: Nulls, integrity, the closed world assumption and events

From: Cimode <cimode_at_hotmail.com>
Date: 8 Jan 2007 02:09:31 -0800
Message-ID: <1168250971.134073.316120@i15g2000cwa.googlegroups.com> 






David wrote:


> Consider the following relation

>

>     person(P,M,F) :-  person P has mother M, father F.

>

> By induction a non-empty

> database would have to be infinite.



A false premise makes all deductions coming from it false.  Closed
World Assumption does not say anything about the number of element that
belong to a domain of values from which one attribute values are
derived.  In the case of a *person* domain, the number of elements in
the set is certainly finite.  Therefore, the number of propositions
involving person as an attribute is limited as well.
Received on Mon Jan 08 2007 - 04:09:31 CST












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