- From: James Howison <james@howison.name>
- Date: Tue, 18 Aug 2009 19:15:46 -0400
- To: public-sparql-dev@w3.org
There really isn't any concept of "nesting" in RDF, that's just a consequence of the particular XML serialization that you are looking at. To grasp this better convert that RDF/XML data to Turtle, then think of SPARQL as filters on those triples. You'll quickly see the path to get the results you want. On 18 Aug 2009, at 6:32 PM, On Lee wrote: > http://danbri.org/foaf.rdf has the following nested info: > > <knows> > > <Person> > > <name>Aaron Swartz</name> > > <made> > > <rss:channel rdf:about="http://www.blogspace.com/rss/rss10"> > > <rss:title>RSS Info</rss:title> > > <rdfs:seeAlso > rdf:resource="http://www.blogspace.com/rss/rss10"/> > > </rss:channel> > > </made> > > <rdfs:seeAlso rdf:resource="http://www.aaronsw.com/ > about.xrdf"/> > > </Person> > > </knows> > > > > http://sparql.org/sparql.html executed the following SPARQL: > > REFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> > > PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> > > PREFIX foaf: <http://xmlns.com/foaf/0.1/> > > > > SELECT * > > WHERE > > { > > <http://danbri.org/foaf.rdf#danbri> foaf:knows ?known . > > ?known ?predicate ?object . > > } > > > > It produced the first level info. For example, > > ?known = _:b19 > > ?predicate = <http://xmlns.com/foaf/0.1/made> > > ?object = <http://www.blogspace.com/rss/rss10> > > > > Based on the above info, I could then get the next level info by the > following SPARQL: "SELECT * WHERE { <http://www.blogspace.com/rss/rss10 > > > ?predicate ?object .}". > > > > How to write a single SPARQL so I could retrieve the nested level > info even > it has 10 levels deep? > > > > Thanks in advance for your help. > > > > Best, > > -- On Lee > > >
Received on Tuesday, 18 August 2009 23:16:34 UTC