Provide the directions for all the trains that have 2 or less cars.
2 or less cars refers to trailPosi < = 2
SELECT T1.direction FROM trains AS T1 INNER JOIN ( SELECT train_id, MAX(position) AS trailPosi FROM cars GROUP BY train_id ) AS T2 ON T1.id = T2.train_id WHERE T2.trailPosi <= 2
database name:db_id trains
cars table cars Cols: id dtype integer, train id dtype integer, position dtype integer, shape dtype text, length dtype text, sides dtype text, roof dtype text, wheels dtype integer, load_shape dtype text, load number dtype integer, 
trains table trains Cols: id dtype integer, direction dtype text, 
