CREATE TABLE happy_hour (hh_id NUMBER, shop_id NUMBER, month CLOB, num_of_shaff_in_charge NUMBER)
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 shop (shop_id NUMBER, address CLOB, num_of_staff CLOB, score NUMBER, open_year CLOB)
CREATE TABLE happy_hour_member (hh_id NUMBER, member_id NUMBER, total_amount NUMBER)

Which month has the most happy hours?
SELECT month FROM happy_hour GROUP BY month ORDER BY COUNT(*) DESC LIMIT 1
SELECT "month" FROM "happy_hour" GROUP BY "month" ORDER BY COUNT(*) DESC FETCH FIRST 1 ROWS ONLY