What is {date of first performance} of {La traviata} that is {musical conductor} is {Gaetano Mares} ?
When did Gaetano Mares first conduct La Traviata?
When was the first performance of La Traviata held with Conductor Gaetano Mares?
SELECT ?o WHERE { resource:La_traviata property:date_of_first_performance ?k . ?k property:musical_conductor resource:Gaetano_Mares . ?k property:date_of_first_performance ?o }
select distinct ?obj  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q186162> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P1191> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> ?obj .
?statement <http://www.wikidata.org/entity/P3300> <http://wikidata.dbpedia.org/resource/Q5516697>
} 

SELECT ?obj WHERE { wd:Q186162 p:P1191 ?s . ?s ps:P1191 ?obj . ?s pq:P3300 wd:Q5516697 }