Question: Show me hiking trails in the Grand Canyon where there's no danger of flash floods.
SPARQL:
SELECT DISTINCT ?uri WHERE { ?uri <http://dbpedia.org/property/trailheads> <http://dbpedia.org/resource/Grand_Canyon> . FILTER NOT EXISTS { ?uri <http://dbpedia.org/property/hazards> <http://dbpedia.org/resource/Flash_flood> . } }