년, 월, 성별 별 상품 구매 회원 수 구하기

문제

코드

SELECT 
    YEAR(ONLINE_SALE.SALES_DATE) AS YEAR, 
    MONTH(ONLINE_SALE.SALES_DATE) AS MONTH, 
    USER_INFO.GENDER, 
    COUNT(DISTINCT ONLINE_SALE.USER_ID) AS USERS
FROM 
    USER_INFO
JOIN 
    ONLINE_SALE ON USER_INFO.USER_ID = ONLINE_SALE.USER_ID
WHERE 
    USER_INFO.GENDER IS NOT NULL
GROUP BY 
    YEAR(ONLINE_SALE.SALES_DATE), 
    MONTH(ONLINE_SALE.SALES_DATE), 
    USER_INFO.GENDER
ORDER BY 
    YEAR(ONLINE_SALE.SALES_DATE) ASC, 
    MONTH(ONLINE_SALE.SALES_DATE) ASC, 
    USER_INFO.GENDER ASC;

 

출처: 프로그래머스 코딩 테스트 연습, https://school.programmers.co.kr/learn/courses/30/lessons/131532