Question: Who is the winner of the 2015 WGC Cadillac Championship dating?
Answer(s):
answer: Paulina Gretzky

SPARQL query:
PREFIX ns: <http://rdf.freebase.com/ns/>
SELECT DISTINCT ?x
WHERE {
FILTER (?x != ?c)
FILTER (!isLiteral(?x) OR lang(?x) = '' OR langMatches(lang(?x), 'en'))
?c ns:award.competitor.competitions_won ns:m.012bnxnq . 
?c ns:celebrities.celebrity.sexual_relationships ?y .
?y ns:celebrities.romantic_relationship.celebrity ?x .
?y ns:celebrities.romantic_relationship.relationship_type ns:m.02_99rl .
FILTER(NOT EXISTS {?y ns:celebrities.romantic_relationship.start_date ?sk0} || 
EXISTS {?y ns:celebrities.romantic_relationship.start_date ?sk1 . 
FILTER(xsd:datetime(?sk1) <= "2015-08-10"^^xsd:dateTime) })
FILTER(NOT EXISTS {?y ns:celebrities.romantic_relationship.end_date ?sk2} || 
EXISTS {?y ns:celebrities.romantic_relationship.end_date ?sk3 . 
FILTER(xsd:datetime(?sk3) >= "2015-08-10"^^xsd:dateTime) })
}