คณะกรรมการชุดไหนมีผู้แทนจากทั้งพรรคประชาธิปัตย์และพรรคเสรีนิยม?ไม่จำเป็นต้องใช้ตารางทั้งหมด
Which committees have delegates from both democratic party and liberal party?It is not neccessary to use all the tables.
 election:  (Committee [ VARCHAR ] Party [ VARCHAR) ]
SELECT T1.Committee FROM election AS T1 JOIN party AS T2 ON T1.Party = T2.Party_ID WHERE T2.Party = "Democratic" INTERSECT SELECT T1.Committee FROM election AS T1 JOIN party AS T2 ON T1.Party = T2.Party_ID WHERE T2.Party = "Liberal"