Question: What is the longest river in China?
SPARQL:
SELECT DISTINCT ?uri WHERE { ?uri a <http://dbpedia.org/ontology/River> . ?uri <http://dbpedia.org/ontology/country> <http://dbpedia.org/resource/China> . ?uri <http://dbpedia.org/property/length> ?l . } ORDER BY DESC(?l) OFFSET 0 LIMIT 1