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Question about literals in subject position

From: Birte Glimm <birte.glimm@comlab.ox.ac.uk>
Date: Tue, 22 Sep 2009 11:44:30 +0100
Message-ID: <492f2b0b0909220344l22213b5brab8aa7a3c1e70def@mail.gmail.com>
To: SPARQL Working Group <public-rdf-dawg@w3.org>
Hi all,
I just wanted to confirm that I understand the specs correctly...
As I read the SPARQL query grammar, I understand it that literals are
allowed in subject position. Thus, a query such as
SELECT ?x WHERE { ?x rdf:type rdf:XMLLiteral }
under say RDF or RDFS entailment would have to return all valid RDF
XML literals (if not sufficently restricted) of which there are
infinitely many. Although RDF itself does not allow literals in
subject position, SPARQL queries do allow it and in fact according to
the RDF(S) semantics (under RDF(S) entailment) the statement XXX
rdf:type rdf:XMLLiteral is entailed by any graph for XXX a valid XML
Literal lexical form. All correct?
Birte


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Received on Tuesday, 22 September 2009 10:45:07 GMT

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