Database: club_leader
Question: Show the names of club leaders that joined their club before 2018.
SQL:
SELECT T3.Name ,  T2.Club_Name FROM club_leader AS T1 JOIN club AS T2 ON T1.Club_ID  =  T2.Club_ID JOIN member AS T3 ON T1.Member_ID  =  T3.Member_ID WHERE T1.Year_Join  <  2018