- From: Yves Raimond <Yves.Raimond@bbc.co.uk>
- Date: Mon, 22 Aug 2011 16:36:43 +0100
- To: Pierre-Antoine Champin <pierre-antoine.champin@liris.cnrs.fr>
- Cc: Richard Cyganiak <richard@cyganiak.de>, RDF Working Group WG <public-rdf-wg@w3.org>
Hello! > As I promissed to Richard during the last TC, I'm reactivating the > thread on his proposal to "lift" the definition of RDF datasets into > from SPARQL to RDF concepts [1] > > My main concern with this proposal is that it defines a somewhat complex > structure (the dataset) as a primitive concept in RDF. My gut feeling is > that we could instead define more basic concepts, on top of which SPARQL > datasets, SPARQL graph stores, and possibly other structures, could be > defined. In my understanding, this is what the g-* terminology was > aiming at. > > In this perspective, back in June, I made an alternate proposal [2] for > which I got almost no feedback. In a nutshell, it provides a minimal > vocabulary for reifying RDF graphs into standard RDF, and sketches the > semantics of such a reification. From there, it illustrates how > multi-graphs syntaxes (such as Trig) and models (such as SPARQL > datasets) can be defined on top of it. > One concern I have with that proposal is that instructions modifying the parsing behavior are embedded within certain URIs (rdf:xml-serialization). Does that mean, when writing an RDF parser, you'd need to manually check for those specific predicates (which would need to be added as soon as there's a new serialisation for RDF ; rdf:jsonld-serialization, rdf:binaryrdf-serialization, rdf:ntriples-utf8-serialization...). Also, the relationship between the holding graphs and the contained graphs would need to be specified exactly - are the prefixes and the base URI shared? On a different note, it might be very difficult to read if you have a graph g quoting a graph g2 quoting a graph g3? Best, y > I know that Richard was concerned about several multi-graph models had > slight differences (e.g. can a BNode be used as a graph name), and his > solution was to endorse one of them and wait for the others to converge. > My proposal is rather to provide the building blocks for everyone to > describe their model in RDF itself, and leave it open for different > models to coexist, which is ok as long as they can all be expressed in > plain RDF. > > pa > > > [1] http://www.w3.org/2011/rdf-wg/wiki/TF-Graphs/RDF-Datasets-Proposal > [2] http://www.w3.org/2011/rdf-wg/wiki/TF-Graphs/RDF-Quadless-Proposal >
Received on Monday, 22 August 2011 15:37:21 UTC