what is the {start time} for {David Gilmour} has {spouse} as {Polly Samson} ?
During what years were Polly Samson and David Gilmour married?
When was Polly Samson the spouse of David Gilmour?
SELECT ?b WHERE { resource:David_Gilmour property:spouse ?o . ?o property:start_time ?b . ?o property:spouse resource:Polly_Samson }
select distinct ?value  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q178517> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P26> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> <http://wikidata.dbpedia.org/resource/Q281036> .
?statement <http://www.wikidata.org/entity/P580> ?value. 
} 

SELECT ?value WHERE { wd:Q178517 p:P26 ?s . ?s ps:P26 wd:Q281036 . ?s pq:P580 ?value}