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

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