[프로그래머스/오라클] 년, 월, 성별 별 상품 구매 회원 수 구하기 - Oracle

https://school.programmers.co.kr/learn/courses/30/lessons/131532

프로그래머스

 

 

SELECT to_char(s.sales_date,'yyyy') as year, 
to_char(s.sales_date,'mm')as month,
I.GENDER AS GENDER,
COUNT(DISTINCT I.USER_ID) AS USERS
FROM USER_INFO I join ONLINE_SALE S on i.user_id = s.user_id
WHERE NOT I.GENDER IS NULL
GROUP BY to_char(s.sales_date,'yyyy'), to_char(s.sales_date,'mm'),I.GENDER
order by 1, 2, 3;