Question: Count the units garrisoned at Arlington County, Virginia.
SPARQL query:
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX res: <http://dbpedia.org/resource/>
PREFIX onto: <http://dbpedia.org/ontology/>
SELECT DISTINCT COUNT(?uri) WHERE {?uri onto:garrison <http://dbpedia.org/resource/Arlington_County,_Virginia> . ?uri rdf:type onto:MilitaryUnit}