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Re: Classes in OWL

From: Richard Newman <r.newman@reading.ac.uk>
Date: Tue, 31 Aug 2004 09:37:20 +0100
Message-Id: <F95F4009-FB28-11D8-BBE5-000A957D9564@reading.ac.uk>
To: rdf-interest <www-rdf-interest@w3.org>

I think what you're trying to say is

C subClassOf B
B subClassOf A
X type C

is X type A?

Theoretically, yes: RDFS says that X can be inferred to be of type A. 
However, in practice you will need either (a) a query language that 
does subclass navigation or inference (a "smart" query language), or 
(b) an inferencing store.

If you have a store or query language that only looks at the raw 
triples (a structural query language), then unless 'X type A' appears 
directly in the data, then you won't get the answer.

Your two options would be:
1. use a store/query language capable of doing this kind of inference
2. use an inferencing store such as Racer to do the processing.

Hope that helps,
-Rich

On 30 Aug 2004, at 04:07, Prajakta Nivargi wrote:

> Well, basically what I am trying to do is create policies. So when I 
> have class A ,B,C where C is subclass of B and B is subclass of A. Now 
> I have a policy defined for objects of type A. So I need to check if 
> my instance of class C is of type class A. That is why I needed to use 
> that predicate. So can I do the check that if - instanceOfC is of 
> rdf;type classA
>
>  That is what I am not sure of.
>
> Thanks,
>
> Prajakta
Received on Tuesday, 31 August 2004 08:38:16 UTC

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