풀이 코드
SELECT USER_ID, PRODUCT_ID
FROM ONLINE_SALE
GROUP BY USER_ID, PRODUCT_ID
HAVING COUNT(USER_ID) >= 2
ORDER BY USER_ID, PRODUCT_ID DESC
항상 성장하는 개발자 최동혁입니다.
SELECT USER_ID, PRODUCT_ID
FROM ONLINE_SALE
GROUP BY USER_ID, PRODUCT_ID
HAVING COUNT(USER_ID) >= 2
ORDER BY USER_ID, PRODUCT_ID DESC