Question: List the total number of executive producer of TV show which have one of the executiive producer as Steven Moffat ?
SPARQL:
 SELECT DISTINCT COUNT(?uri) WHERE { ?x <http://dbpedia.org/ontology/executiveProducer> <http://dbpedia.org/resource/Steven_Moffat> . ?x <http://dbpedia.org/property/executiveProducer> ?uri }