CommentResponse:PF-1

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Philip Fennell wrote:

> I've had a quick look in the archive but have not found anything the immediately answers my questions, which is:
>
>I'm not sure I understand the distinction between Direct Graph Identification and Indirect Graph Identification that uses the graph request parameter to identify a named graph.
>
>With respect to Direct Graph Identification (section 4.1 of the SPARQL 1.1 Graph Store HTTP Protocol) can I deduce from the following statements:
>
>'Per [RFC2616]<http://www.w3.org/TR/sparql11-http-rdf-update/>, the most common usage of a Request-URI is to identify a resource on an origin server or gateway. In our example, the 
>corresponding request URI (http://example.com/rdf-graphs/employees) is meant to identify RDF triples on the example.com server that describe employees. In addition, the request specifies the  
>GET method, which means that a representation of these triples should be returned. In this case, the preferred representation format is application/rdf+xml
>
>In this way, the server would route operations on a named graph in an Graph Store via its Graph IRI. However, in using a URI in this way, we are not directly identifying an RDF graph but rather the RDF graph content that is represented by an RDF document, which is a serialization of that graph. Intuitively, the set of interpetations that satisfy [RDF-MT]<http://www.w3.org/TR/sparql11-http-rdf-update/> the RDF graph that the RDF document is a serialization of can be thought of as this RDF graph content.'
> that by using 'Direct Graph Identification', the graph content that you would be addressing with:
   <http://example.com/rdf-graphs/employees>
> is a 'Named Graph' and an equivalent request would be, for example:
   <http://example.com/rdf-graphs?graph= http%3A%2F%2Fexample.com%2Frdf-graphs%2Femployees>

Philip,

Yes, this is correct, assuming

   http://example.com/rdf-graphs

Identifies a Graph Store managed by an HTTP service that is an implementation of this protocol and

   http://example.com/rdf-graphs/employees

is the graph IRI associated with an RDF graph within that Graph Store

We would be grateful if you would acknowledge that your comments have been answered by sending a reply to this mailing list.

Regards, Chime Ogbuji, on behalf of the SPARQL WG.