Question: When did Metro Manila have a population of 794,839?
Paraphrase: Name the date the city of Manila has a population of 794,839.
SPARQL (Wikidata): SELECT ?value WHERE { wd:Q13580 p:P1082 ?s . ?s ps:P1082 ?x filter(contains(?x , '7.94839e+06')) . ?s pq:P585 ?value}