Given a stop from which connections departure, return a list of following stops

next_stops.sql

-- Query GTFS tables
SELECT DISTINCT
  x.stop_id,
  next_stop,
  stops.stop_name
FROM 
  (
  SELECT
    stop_id,
    stop_sequence,
    LEAD (stop_id) OVER (PARTITION BY trip_id ORDER BY CAST(stop_sequence AS INTEGER)) next_stop
  FROM stop_times
  ) AS x
JOIN
  stops on next_stop = stops.stop_id
WHERE                    -- comment these lines
  x.stop_id = "U100Z1P"  -- to get a complete set of pairs
ORDER BY
  x.stop_id, next_stop