Q3-naive.sparql

PREFIX  dbpp: <http://dbpedia.org/property/>
PREFIX  dbpo: <http://dbpedia.org/ontology/>
PREFIX  rdf:  <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX  yagoinfo: <http://yago-knowledge.org/resource/infobox/en/>
PREFIX  yago: <http://yago-knowledge.org/resource/>
PREFIX  dcterms: <http://purl.org/dc/terms/>
PREFIX  rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX  dbpr: <http://dbpedia.org/resource/>

SELECT  *
WHERE
  { GRAPH <http://dbpedia.org>
      { { SELECT  *
          WHERE
            { { SELECT  *
                WHERE
                  { ?film1  dbpp:starring  ?actor1 }
              }
              { SELECT  *
                WHERE
                  { ?actor1  dbpp:birthPlace  ?actor_country1 }
              }
              { SELECT  *
                WHERE
                  { ?actor1  dbpp:name  ?name }
              }
            }
        }
        FILTER regex(str(?actor_country1), "USA")
      }
    GRAPH <http://yago-knowledge.org/>
      { { SELECT  *
          WHERE
            { { SELECT  *
                WHERE
                  { ?actor2  yago:actedIn  ?film2 }
              }
              { SELECT  *
                WHERE
                  { ?actor2  yago:isCitizenOf  ?actor_country2 }
              }
              { SELECT  *
                WHERE
                  { ?actor2  yagoinfo:name  ?name }
              }
            }
        }
        FILTER ( ?actor_country2 = yago:United_States )
      }
  }