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hasKey axioms allowed for the empty set of properties

From: Michael Schneider <schneid@fzi.de>
Date: Sat, 4 Jul 2009 19:09:16 +0200
Message-ID: <0EF30CAA69519C4CB91D01481AEA06A0014C65FA@judith.fzi.de>
To: "W3C OWL Working Group" <public-owl-wg@w3.org>
Hi!

In the reverse RDF-Mapping of owl:hasKey, there is no constraint on the size of the argument list. This means that a key axiom may be defined for the empty set of properties. Also, it looks to me that the empty set is allowed in the Structural Specification (Functional Syntax), either. 

I don't think that empty key axioms are particularly useful, and I can see that they have peculiar semantic ramifications.

So I propose to require at least one property for key axioms in both the Structural Spec and the reverse RDF-Mapping.

Cheers,
Michael

--
Dipl.-Inform. Michael Schneider
Research Scientist, Dept. Information Process Engineering (IPE)
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Received on Saturday, 4 July 2009 17:09:56 GMT

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