Virtuoso DBpedia“英语以外的其他语言”图表

Question

I'm trying to use Virtuoso with ita-Dbpedia dumps. These are the steps i've done using the guide:

1: Installed virtuoso and made a Service (called "Nostromo"). 2: Downloaded Dumps 3: Bulkloaded dumps 4: registered graph iri with (SQL> ld_dir ('tmp', ' . ', ' http://dbpedia.org ') 5: Inserted the graph file in the 6: started the loader Run: SQL> rdf_loader_run (); (5 hours wait...)

Than all seems good but when i try to sparql something it results empty...

with the SQL command:

SELECT ll_graph, ll_file FROM DB.DBA.LOAD_LIST;

it comes: Query result:

> ll_graph VARCHAR  ll_file VARCHAR  http://it.dbpedia. org 
> tmp/itwiki-20140302-article-categories.ttl  http:// it.dbpedia. org   
> tmp/itwiki-20140302-article-templates.ttl  http:// it.dbpedia. org    
> tmp/itwiki-20140302-available_interlanguage-links.ttl 
> http:// it.dbpedia. org    tmp/itwiki-20140302-category-labels.ttl 
> http:// it.dbpedia. org    tmp/itwiki-20140302-disambiguations.ttl 
> http:// it.dbpedia. org    tmp/itwiki-20140302-external-links.ttl 
> http:// it.dbpedia. org    tmp/itwiki-20140302-geo-coordinates.ttl 
> http:// it.dbpedia. org    tmp/itwiki-20140302-images.ttl 
> http:// it.dbpedia. org    tmp/itwiki-20140302-infobox-properties.ttl 
> http:// it.dbpedia. org   
> tmp/itwiki-20140302-infobox-property-definitions.ttl 
> http:// it.dbpedia. org    tmp/itwiki-20140302-infobox-test.ttl 
> http:// it.dbpedia. org    tmp/itwiki-20140302-instance-types.ttl 
> http:// it.dbpedia. org    tmp/itwiki-20140302-interlanguage-links.ttl 
> http:// it.dbpedia. org    tmp/itwiki-20140302-labels.ttl 
> http:// it.dbpedia. org   
> tmp/itwiki-20140302-mappingbased-properties.ttl  http://it.dbpedia.
> org    tmp/itwiki-20140302-page-ids.ttl  http://it.dbpedia. org   
> tmp/itwiki-20140302-page-links.ttl  http://it.dbpedia. org    
> tmp/itwiki-20140302-redirects.ttl  http://it.dbpedia. org 
> tmp/itwiki-20140302-revision-ids.ttl  http://it.dbpedia. org  
> tmp/itwiki-20140302-revision-uris.ttl

and with:

SELECT ?g COUNT(*) { GRAPH ?g {?s ?p ?o.} };

it comes:

g   callret-1
http://www.w3. org/2002/07/owl# 160
http://it.dbpedia. org  86712483
http://www.openlinksw. com/schemas/virtrdf# 2639
http://local.host:8890/sparql   14
http://local.host:8890/DAV/ 2939

pratically i know that there are the triples, but i can't query them...

PS: for example i use a query that works fine in another ita-sparql endpoint, but it's not good for mine...

SELECT ?museum, ?artwork WHERE {
?museum a <http://dbpedia.org/ontology/Museum>. 
?museum <http://dbpedia.org/ontology/address> ?address.
?artwork <http://dbpedia.org/ontology/location> ?museum.
 FILTER contains(?address, "Firenze")
}

I think it's a quite stupid mistake i've done, but i can't find it...

UPDATE 07/01/2014

With this query i got a result:

select ?museum where {
  graph <http://it.dbpedia.org> {
    ?museum a <http://dbpedia.org/ontology/Museum>. 

  }
}

But no news with the other query I think it's about ontology...

are there some query/interrogation i can do for help you understand this problem? (Thanks in advance)

UPDATE 11/01/2014

Ok, i have found the problem... that was not about owl but about type of dumps. I resolved installing a VAD for faceted browsing and take the info about triple from local.host:8890/fct search engine. Just a few modifies in the queries and all works good... :D Thanks all, expecially to mr.Taylor

Answer 1

The result

http://it.dbpedia.org    86712483

in your original query means that there are 86712483 in the graph named http://it.dbpedia.org. Your second query:

select ?museum, ?artwork where {
  ?museum a <http://dbpedia.org/ontology/Museum>. 
  ?museum <http://dbpedia.org/ontology/address> ?address.
  ?artwork <http://dbpedia.org/ontology/location> ?museum.
  filter contains(?address, "Firenze")
}

is a query over the default graph . Some SPARQL endpoints make the default graph a union of all the other graphs, but this isn't universal, and it appears that it is not what Virtuoso does (or at least not by default). You need to specify the actual named graph. Eg, the following query will probably get you some results:

select ?museum, ?artwork where {
  graph <http://it.dbpedia.org> {
    ?museum a <http://dbpedia.org/ontology/Museum>. 
    ?museum <http://dbpedia.org/ontology/address> ?address.
    ?artwork <http://dbpedia.org/ontology/location> ?museum.
    filter contains(?address, "Firenze")
  }
}