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Re: Integrity Checking vs. Typing [Re: RDFS bug "A property can have at most one range property"]

From: Dan Brickley <danbri@w3.org>
Date: Sun, 18 Nov 2001 12:15:39 -0500 (EST)
To: "Peter F. Patel-Schneider" <pfps@research.bell-labs.com>
cc: <conen@gmx.de>, <www-rdf-interest@w3.org>
Message-ID: <Pine.LNX.4.30.0111181214140.8575-100000@tux.w3.org>
On Sun, 18 Nov 2001, Peter F. Patel-Schneider wrote:

> From: Wolfram Conen <conen@gmx.de>
> Subject: Integrity Checking vs. Typing [Re: RDFS bug "A property can have at most   one range property"]
> Date: Sat, 17 Nov 2001 17:14:42 +0100
>
> > [The context below is RDFS, I briefly discuss two interpretations of
> > domain/range (the old one suggested by the RDFS CR and the newer,
> > DAMLish interpretation) and claim that choosing either of this
> > interpretations has a different impact on deciding the
> > disjunctive/conjunctive question. I also discuss the usefulness of both
> > interpretations with respect to certain application context and show
> > that the newer interpretation is less expressive. Sorry for returning to
> > this issue but, as I briefly discuss below, the discussion has mixed
> > different issues from the beginning and seldom discussed (application)
> > requirements beyond compatibility to DAML/OIL.]
>
> If you are making any claims as to what the RDFS CR suggests, then I think
> that you have to consider the second paragraph of its section on
> constraints:
>
>   RDF Schema provides a mechanism for describing such constraints, but does
>   not say whether or how an application must process the constraint
>   information.  For example, while an RDF schema can assert that an
>   <code>author</code> property is used to indicate resources that are
>   members of the class <code>Person</code>, it does not say whether or how
>   an application should act in processing that class information. We expect
>   that different applications will use these constraints in different ways
>   - e.g., a validator will look for errors, an interactive editor might
>   suggest legal values, and a reasoning application might infer the class
>   and then announce any inconsistencies.
>
> There you have it---the ultimate cop-out.
>
> >From this, I don't see how anyone can claim that the RDFS CR comes down on
> the side of integrity constraints.

If anything, we err by suggesting integrating checking might be done
without bringing additional information to bear, eg. that two classes are
disjoint, or application specific concerns that don't apply to all uses
of some schema.

Dan


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Received on Sunday, 18 November 2001 12:15:44 GMT

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