Hey Rob,
> I've noticed a couple of examples where there seem to be entries at > http://dbpedia.org/page/ but when performing a SPARQL query against the > dataset I get no results returned e.g. > > http://dbpedia.org/page/iPhone > > returns a page with data but running : > > SELECT ?predicate ?object WHERE { <http://dbpedia.org/resource/iPhone> > ?predicate ?object . } > > at the SPARQL interface returns no results. Interesting one... > > Could someone explain why ? Yes, I can. There simply are no triples matching the pattern {dbpedia:iPhone ?p ?o . } The output pages (dbpedia.org/page/ and dbpedia.org/data/) are generated on-the-fly via a "DESCRIBE <x>" query, which is equivalent (in Virtuoso's implementation, no necessarily by spec) to SELECT * where { <x> ?p ?o . } UNION SELECT * where { ?s ?p <x> . } In your example, there are only S P dbpedia:iPhone triples available. If you look at dbpedia.org/page/iPhone you will see, that the properties are named "is blabla of", which indicates that those triples match to { ?s ?p dbpedia:iPhone .} Apple's mobile phone you are looking for has the URI http://dbpedia.org/resource/IPhone (with an upper case "I"). That's really an interesting example, because the URI does not match the article's title in Wikipedia (which has a lower case "i"). Best, Georgi -- Georgi Kobilarov Freie Universität Berlin www.georgikobilarov.com ------------------------------------------------------------------------- This SF.net email is sponsored by the 2008 JavaOne(SM) Conference Don't miss this year's exciting event. There's still time to save $100. Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone _______________________________________________ Dbpedia-discussion mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/dbpedia-discussion
