cygri / void

An RDF schema and associated documentation for expressing metadata about RDF datasets
http://www.w3.org/TR/void/
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Implications of DCAT for VoID and SPARQL-SD #110

Open GoogleCodeExporter opened 9 years ago

GoogleCodeExporter commented 9 years ago
This was raised by Tim Lebo via email. Quoting Tim:

=============
I was having another read of http://www.w3.org/TR/2011/NOTE-void-20110303/ 
which says:

[[
:DBpedia a void:Dataset;
   void:sparqlEndpoint <http://dbpedia.org/sparql>;
   .

Note: In some SPARQL endpoints, named graphs are used to partition the data. 
Currently VoID doesn't provide a dedicated way of stating that a dataset is 
contained in a specific named graph. This kind of information can be provided 
in a SPARQL Service Description, as described below.
]]

and then defers to http://www.w3.org/TR/2011/NOTE-void-20110303/#sparql-sd 
which doesn't mention the ":DBPedia" from the more simple description above.

While I agree with the alignment that you describe between VoID and SD, I find 
that a "pure SD" description loses the "dataset focus" since one needs to dig 
"backwards" through a bit of subgraph structuring to find out where, exactly, 
the dataset resides.

Perhaps the following description would be a more direct way to state, as you 
say, "a dataset is contained in a specific named graph.":

:DBPedia
   a void:Dataset;
   dcterms:title "DBpedia";
   foaf:homepage <http://dbpedia.org/>;
   void:triples 1000000000;

   dcat:distribution [
         a sd:NamedGraph;
         sd:name              <http://dbpedia.org/> ;
         prov:atLocation <http://example.org/geopedia/sparql>;   # Where, the understanding is that there is some [ a sd:Service; sd:endpoint <http://example.org/geopedia/sparql> ]
  ];
.

I was wondering if any of you find objection to this modeling, since I've come 
to like its directness.

Also, since I'm introducing dcat, perhaps void:dataDump should be deprecated in 
favor of dcat:distribution [ dcat:downloadURL ] (which, I guess goes against 
the desire for directness…)
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Original issue reported on code.google.com by richard....@gmail.com on 28 Nov 2013 at 2:38