Question: How many people have trained the wrestlers who were billed in Wisconsin?
SPARQL:
SELECT DISTINCT COUNT(?uri) WHERE { ?x <http://dbpedia.org/ontology/billed> <http://dbpedia.org/resource/Wisconsin> . ?x <http://dbpedia.org/ontology/trainer> ?uri  . ?uri <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dbpedia.org/ontology/Person>}