Database: train_station
Question: Show all train names and times in stations in London in descending order by train time.
SQL: select t3.name ,  t3.time from train_station as t1 join station as t2 on t1.station_id  =  t2.station_id join train as t3 on t3.train_id  =  t1.train_id where t2.location  =  'london' order by t3.time desc