[SQL 고득점 Kit / GROUP BY ] Level 3 - 카테고리 별 도서 판매량 집계하기

문제

성공 코드

SELECT B.CATEGORY, SUM(S.SALES) AS TOTAL_SALES
FROM BOOK B JOIN BOOK_SALES S ON B.BOOK_ID = S.BOOK_ID
WHERE YEAR(S.SALES_DATE) = 2022 AND MONTH(S.SALES_DATE) = 1
GROUP BY B.CATEGORY
ORDER BY B.CATEGORY