Database: student_club (difficulty: simple)
Question: Calculate the total amount spent on Club T-Shirts and list the name of the event they were spent on.
SQL: SELECT SUM(T1.spent), T2.event_name FROM budget AS T1 INNER JOIN event AS T2 ON T1.link_to_event = T2.event_id WHERE T1.category = 'Club T-Shirts' GROUP BY T2.event_name