What is {friends} of {key event} of {Hamburg} ?
Whose friends were at the event in Hamburg?
Who are the friends of a key event in Hamburg?
SELECT ?a WHERE { resource:Hamburg property:significant_event ?z . ?z property:significant_person ?a }
SELECT ?answer WHERE { ?statement1 <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q1055> . ?statement1 <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P793>. ?statement1 <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> ?X . ?statement2 <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> ?X. ?statement2 <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P3342> . ?statement2 <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> ?answer . }
SELECT ?answer WHERE { wd:Q1055 wdt:P793 ?X . ?X wdt:P3342 ?answer}