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Re: RDF graphs SPARQL does not query

From: Seaborne, Andy <andy.seaborne@hp.com>
Date: Mon, 12 Mar 2007 15:00:23 +0000
Message-ID: <45F56B07.1070600@hp.com>
To: Eric Prud'hommeaux <eric@w3.org>
CC: public-rdf-dawg@w3.org



Eric Prud'hommeaux wrote:
> 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. 

Andy is mainly opposed to putting this in the introduction section called 
"Document Terminology".  It seems to be getting into the fine details at the 
wrong point.

The text could go in A.5:

[[
URI references containing "<", ">", '"', space, "{", "}", "|", "\", "^",
and "`" are not IRIs. The behavor of a SPARQL query against RDF
statements composed of such URI references is not defined.
]]

Tweak:
s/URI references/RDF URI references/  (URI references are the non-absolute 
form)  RDF graphs, nor SPARQL ever have URI/IRI references which are not 
URIs/IRIs  (RFC 3986/86 kind) except for surface syntax in the query string.




> 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.

Woudln't SPARQL would be handling the %-encoded form of RDF URI references, 
not the abstract form?

RU then says:
[[
Note: this section anticipates an RFC on Internationalized Resource 
Identifiers. Implementations may issue warnings concerning the use of RDF URI 
References that do not conform with [IRI draft] or its successors.
]]
so I think we can refer the reader to RU, not repeat the text in our spec.

	Andy


> 
> 
> [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
Received on Monday, 12 March 2007 15:00:38 GMT

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