Question: How many politicians are in the US Senate?
SPARQL query:
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX prop: <http://dbpedia.org/property/>
PREFIX onto: <http://dbpedia.org/ontology/>
SELECT DISTINCT COUNT(?uri) WHERE {?uri prop:order <http://dbpedia.org/resource/United_States_Senate>  . ?uri rdf:type onto:OfficeHolder}