재구매가 일어난 상품과 회원 리스트 구하기

https://school.programmers.co.kr/learn/courses/30/lessons/131536

• 문제 풀이

SELECT USER_ID, PRODUCT_ID
FROM ONLINE_SALE
GROUP BY USER_ID, PRODUCT_ID
HAVING COUNT(*) > 1
ORDER BY USER_ID, PRODUCT_ID DESC;

SELECT USER_ID, PRODUCT_ID
FROM ONLINE_SALE
GROUP BY USER_ID, PRODUCT_ID
HAVING COUNT(PRODUCT_ID) > 1
ORDER BY USER_ID, PRODUCT_ID DESC;

• 실행 결과