Number of incoming link fo each DBpedia resource

问题

I have the SPARQL DBpedia Query below:

PREFIX rdfs:   <http://www.w3.org/2000/01/rdf-schema#>
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
PREFIX vrank:<http://purl.org/voc/vrank#>
PREFIX dbpedia-owl: <http://dbpedia.org/ontology/>
SELECT distinct  ?Nom ?resource ?url (count( (?o) as ?nb))
 WHERE{
   ?resource rdfs:label ?Nom.
   ?resource foaf:isPrimaryTopicOf ?url.
   ?resource dbpedia-owl:wikiPageWikiLink ?o
   ?Nom <bif:contains> "Apple".
   FILTER ( langMatches( lang(?Nom), "EN" )).
MINUS {?resource dbo:wikiPageRedirects|dbo:wikiPageDisambiguates  ?dis}
    }
Group By  ?Nom ?resource ?url

I want to get the number of incoming links of each entitie within wikipedia. How can I proceed? Thanks

回答1:

First of all syntax:

you are missing a dot after ?o, also it should be bif:contains, not <bif:contains>.

i ran this simpler query:

PREFIX rdfs:   <http://www.w3.org/2000/01/rdf-schema#>
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
PREFIX vrank:<http://purl.org/voc/vrank#>
PREFIX dbpedia-owl: <http://dbpedia.org/ontology/>
SELECT distinct  ?Nom ?resource
 WHERE{
   ?resource rdfs:label ?Nom.
   ?Nom bif:contains "Apple".
}

which produced a lot of results.... now i added this triple:

PREFIX rdfs:   <http://www.w3.org/2000/01/rdf-schema#>
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
PREFIX vrank:<http://purl.org/voc/vrank#>
PREFIX dbpedia-owl: <http://dbpedia.org/ontology/>
SELECT distinct  ?Nom ?resource
 WHERE{
   ?resource rdfs:label ?Nom.
   ?resource dbpedia-owl:wikiPageWikiLink ?o.
   ?Nom bif:contains "Apple".
}

which returned no results.

this means there is no triple containing apple in its object literal, where the subject has a wikiPageWikiLink in the whole endpoint.

If this property does exist, its instances are not included in the official endpoint since there is no triple containing this property (I checked). This is probably due to the fact, that the official endpoint does not hold every dbpedia dataset, or it might be deprecated.

来源：https://stackoverflow.com/questions/34810267/number-of-incoming-link-fo-each-dbpedia-resource

标签

sparql

dbpedia