Which courses were taught by a professor who is not a faculty member?
courses refers to taughtBy.course_id; professor refers to professor = 1; is not a faculty member refers to hasPosition = 0
SELECT DISTINCT T2.course_id FROM person AS T1 INNER JOIN taughtBy AS T2 ON T1.p_id = T2.p_id WHERE T1.professor = 1 AND T1.hasPosition = 0