Question: What are the airlines whose hub is San Francisco International Airport?
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 ?uri WHERE {?uri prop:hubs <http://dbpedia.org/resource/San_Francisco_International_Airport>  . ?uri rdf:type onto:Airline}