Question: Give me the total number of employer of the engineers whose one of the employer is McDonnell Aircraft?
SPARQL query:
PREFIX res: <http://dbpedia.org/resource/>
PREFIX onto: <http://dbpedia.org/ontology/>
SELECT DISTINCT COUNT(?uri) WHERE { ?x onto:employer <http://dbpedia.org/resource/McDonnell_Aircraft> . ?x onto:employer ?uri }