- From: Nathan <nathan@webr3.org>
- Date: Tue, 19 Apr 2011 12:11:24 +0100
- To: Mischa Tuffield <mischa.tuffield@garlik.com>
- CC: public-rdf-wg Group WG <public-rdf-wg@w3.org>, Andy Seaborne <andy.seaborne@epimorphics.com>
Mischa Tuffield wrote: > Hi All, > > <snip/> > > On 18 Apr 2011, at 20:08, Andy Seaborne wrote: > >> Dan, >> >> Good example. >> >> There are various ways the SPARQL dataset notion can be used. IRI for each g-snap of the same g-box is certainly one of them. >> >> The whole concept of RDF datasets was a recognition that quad usage existed. "RDF dataset" is a compromise from various existing practices, from systems using the word "context" (usually collection of triples as subset of the graph) to multi-graph usages as you describe and variations in between. >> >> On 18/04/11 15:27, Dan Brickley wrote: >>> [snip] >>> >>> Let me offer a practical use case: the evolving RDF graphs served from >>> FOAF and Dublin Core namespace URIs. >>> >>> For the FOAF case xmlns="http://xmlns.com/foaf/0.1/", the RDF >>> available (via conneg, link rel or sometimes embedded in HTML) can be >>> found in our Subversion server at >>> http://svn.foaf-project.org/foaf/trunk/xmlns.com/htdocs/foaf/0.1/index.rdf >>> ... you can fetch any version going back to ~2002 via public SVN. >>> >>> For the Dublin Core case, xmlns="http://purl.org/dc/elements/1.1/" and >>> others nearby are documented in http://dublincore.org/schemas/rdfs/ >>> including links to each version of the schema file, and with >>> social/process documentation of those changes at >>> http://dublincore.org/usage/terms/history/ >>> >>> Consider a SPARQL service devoted to keeping record of what key >>> namespaces have said about themselves over the years. They could take >>> each of these snapshot RDF files and put the corresponding triples in >>> a different named graph. (Maybe we should prepare N-Quads/Trig dumps >>> of the data for testing?). >> and reserve the N-Quads and Trig as a syntax for RDF datasets. > > +1 to this. > > I find it important that the quad based serialisations are kept separate from the various triple-based RDF syntaxes . Ideally, the RDF will continue talking about triples (i.e. a minimum amount of change to the RDF Semantics), and the quad based serialisation will be standardised in order to allow interoperability between SPARQL stores. Couldn't have expressed that better myself, +1
Received on Tuesday, 19 April 2011 11:12:12 UTC