[MySQL] 년, 월, 성별 별 상품 구매 회원 수 구하기

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