CREATE TABLE happy_hour_member (hh_id NUMBER, member_id NUMBER, total_amount NUMBER)
CREATE TABLE shop (shop_id NUMBER, address CLOB, num_of_staff CLOB, score NUMBER, open_year CLOB)
CREATE TABLE member (member_id NUMBER, name CLOB, membership_card CLOB, age NUMBER, time_of_purchase NUMBER, level_of_membership NUMBER, address CLOB)
CREATE TABLE happy_hour (hh_id NUMBER, shop_id NUMBER, month CLOB, num_of_shaff_in_charge NUMBER)

Which address has both members younger than 30 and members older than 40?
SELECT address FROM member WHERE age < 30 INTERSECT SELECT address FROM member WHERE age > 40
SELECT "address" FROM "member" WHERE "age" < 30 INTERSECT SELECT "address" FROM "member" WHERE "age" > 40