the roller coaster with an accident after 08/14/1979 was designed by whom?
Entity Entity Entity Entity Entity
m.027lfxy m.04gvyp m.06vnh2 m.0dpmr9 m.046k63
Tony Baxter Walt Disney Imagineering Werner Stengel William Cobb Arrow Dynamics
class class class literal
amusement_parks.ride_designer amusement_parks.roller_coaster amusement_parks.accident 1979-08-14^^http://www.w3.org/2001/XMLSchema#date
amusement_parks.ride_designer amusement_parks.roller_coaster amusement_parks.accident type.datetime
Amusement Ride Designer Roller Coaster Amusement Ride Accident 08/14/1979
none none none >=
amusement_parks.ride_designer.rides amusement_parks.accident.ride amusement_parks.accident.date
Rides Designed Ride Date
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> PREFIX : <http://rdf.freebase.com/ns/> 
SELECT (?x0 AS ?value) WHERE {
SELECT DISTINCT ?x0  WHERE { 
?x0 :type.object.type :amusement_parks.ride_designer . 
?x1 :type.object.type :amusement_parks.roller_coaster . 
?x2 :type.object.type :amusement_parks.accident . 
FILTER (?x3 >= "1979-08-14-08:00"^^<http://www.w3.org/2001/XMLSchema#date>)
?x0 :amusement_parks.ride_designer.rides ?x1 . 
?x2 :amusement_parks.accident.ride ?x1 . 
?x2 :amusement_parks.accident.date ?x3 . 
FILTER ( ?x0 != ?x1 && ?x0 != ?x2 && ?x0 != ?x3 && ?x1 != ?x2 && ?x1 != ?x3 && ?x2 != ?x3  )
}
}
(AND amusement_parks.ride_designer (JOIN amusement_parks.ride_designer.rides (JOIN (R amusement_parks.accident.ride) (ge amusement_parks.accident.date 1979-08-14^^http://www.w3.org/2001/XMLSchema#date))))