what is the {start time} for {Alexandra Fyodorovna} has {spouse} as {Nicholas II of Russia} ?
What was the date that Alexandra Fyodorvna marry when he was Nicholas II of Russia?
When did Alexandra Fyodorovna marry when he was Nicholas II of Russia?
SELECT ?k WHERE { resource:Alexandra_Feodorovna property:spouse ?e . ?e property:spouse resource:Nicholas_II_of_Russia . ?e property:start_time ?k }
select distinct ?value  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q152094> .
?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/Q40787> .
?statement <http://www.wikidata.org/entity/P580> ?value. 
} 

SELECT ?value WHERE { wd:Q152094 p:P26 ?s . ?s ps:P26 wd:Q40787 . ?s pq:P580 ?value}