What are the names of parties with 2 events
SELECT T2.party_name FROM party_events AS T1 JOIN party AS T2 ON T1.party_id   =   T2.party_id GROUP BY T1.party_id HAVING count ( * )   =   2
names of parties with 2 events refers to party_name; condition of having 2 events is expressed by HAVING COUNT(*) = 2; JOIN is used to combine rows from two or more tables based on a related column between them.