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Re: V. odd example

From: Seaborne, Andy <andy.seaborne@hp.com>
Date: Wed, 13 Apr 2005 09:14:47 +0100
Message-ID: <425CD4F7.5080609@hp.com>
To: Bijan Parsia <bparsia@isr.umd.edu>
CC: DAWG Mailing List <public-rdf-dawg@w3.org>



Bijan Parsia wrote:
> http://www.w3.org/2001/sw/DataAccess/rq23/#GraphPatternMatching
> 
> I find the example:
> 
> 	SELECT ?x ?v WHERE ( ?x ?x ?v )
> 
> against
> 	rdf:type rdf:type rdf:Property .
> 
> and
> 	rdfs:seeAlso rdf:type rdf:Property .
> 
> To be a bit abstruse, involving reflection on the rdf syntax. Perhaps 
> the following would do just as well, and be more in the spirit of the 
> other examples:
> 
> 	SELECT ?x ?v WHERE ( ?x ?v ?x)
> 
> against:
> 	:bob ns:loves :bob
> 
> and
> 	:bob ns:loves :mary

I will see about a new example.

> 
> (Actually, I don't know how this query would behave/ought to behave in 
> the presense of equivalentTos and other OWLisms)

Is there an example you woudl provide to illusrate the problems?

As an RDF query language, all that matters is the appearance of the graph to 
graph pattern matching.  How that graph came about is outside pattern matching.

> 
> In any case, something a bit more concrete seems to be in order.
> 
> Actually, you could just have
> 
> 	SELECT ?x ?v WHERE ( ?x foaf:knows :mary)
> 
> against
> 	:bob foaf:knows :mary.

That is a bit odd because FOAF is typically bNodes for people, not URIs. 
Generally, we have tried to use FOAF in "the usual way" (an undefined term :-).

> 
> and
> 	:bob foaf:knows :george.
> 
> or
> 	:bob dc:creator "Foo".
> 
> I really think this example should be as simple and concrete as 
> possible.
> 
> Cheers,
> Bijan.
> 
> 

	Thanks
	Andy
Received on Wednesday, 13 April 2005 08:15:01 GMT

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