CREATE TABLE performance (performance_id NUMBER, date CLOB, host CLOB, location CLOB, attendance NUMBER)
CREATE TABLE member (member_id CLOB, name CLOB, nationality CLOB, role CLOB)
CREATE TABLE member_attendance (member_id NUMBER, performance_id NUMBER, num_of_pieces NUMBER)

Show the locations that have at least two performances.
SELECT location FROM performance GROUP BY location HAVING COUNT(*) >= 2
SELECT "location" FROM "performance" GROUP BY "location" HAVING COUNT(*) >= 2