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RDF graphs SPARQL does not query

From: Eric Prud'hommeaux <eric@w3.org>
Date: Mon, 12 Mar 2007 10:34:48 -0400
To: public-rdf-dawg@w3.org
Message-ID: <20070312143448.GC21623@w3.org>
Can users expect
  ASK {?s ?p ?o}
to match
  _:x <uri:example.com |{}> _:y .
?

1.2.4 Terminology [TM] currently has:
[[
RDF Concepts and Abstract Syntax was drafted before the IRI
specification and "anticipates an RFC on Internationalized
Resource Identifiers". SPARQL implementations may issue warnings
concerning the use of RDF URI References that do not conform with
[IRI draft] or its successors.
]]

Warnings aside, I don't know from this how SPARQL behaves when
matching URI reference terms that are not IRIs. I'd prefer to leave
that ouside SPARQL so I propose:

[[
The set of RDF terms defined in RDF Concepts and Abstract Syntax
includes URI references while SPARQL terms include IRIs. URI
references containing "<", ">", '"', space, "{", "}", "|", "\", "^",
and "`" are not IRIs. The behavoir of a SPARQL query against RDF
statements composed of such URI references is not defined.
]]


Andy is opposed to opening the can of non-conformant RDF graphs
box. For example, ones you can't serialize in RDFXML (say, URI that's
an xpointer). I think that we only have to address the non-IRI ones.

Also at issue is the exact set of characters that differ. I got this
list from the WSDL spec which eval'd (- RFC3987 RFC3986) [WS], but I'm
not confident that it's exactly right as i'm not sure that RDF URI
references [RU] line up exactly with 3986.


[TM] http://mouni.local/2001/sw/DataAccess/rq23/rq25#docTerminology
[WS] http://dev.w3.org/cvsweb/~checkout~/2002/ws/desc/wsdl20/wsdl20.html?content-type=text/html;%20charset=utf-8#xmlSchemaAnyURI
[RU] http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/#dfn-URI-reference
-- 
-eric

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Received on Monday, 12 March 2007 14:35:57 GMT

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