Re: Multiple-Attribute Keys and 1NF

> I have three propositions, and hopefully we'd agree there are two
> roles in these propositions: name and speaks_language. So in FOL I
> could write these propositions as:
> [P1] Name(x, Jim) -> speaks_language(x, English)
> [P2] Name(x, Jim) -> speaks_language(x, German)
> [P3] Name(x, Brian) -> speaks_language(x, English)

In dbd, the above are expressed as:

(new 'speak 'verb)

(new 'english 'language)
(new 'german 'language)

(new 'jim 'person)
(set jim speak english)
(set jim speak german)

(new 'brian 'person)
(set brian speak english)

(; Get persons who speaks english)
(; Gets jim and brian)
(get * speak english)

(; Get persons who speak english and german)
(; Ges jim)
(& (get * speak english)

    (get * speak german)) Received on Thu Aug 30 2007 - 23:18:31 CEST