[SQL 문제 풀이] 조건에 맞는 사원 정보 조회하기

SELECT 
    A.AUTHOR_ID,
    A.AUTHOR_NAME,
    B.CATEGORY,
    SUM(S.SALES * B.PRICE) AS TOTAL_SALES
FROM 
    AUTHOR A
JOIN 
    BOOK B ON A.AUTHOR_ID = B.AUTHOR_ID
JOIN 
    BOOK_SALES S ON B.BOOK_ID = S.BOOK_ID
WHERE 
    S.SALES_DATE BETWEEN '2022-01-01' AND '2022-01-31'
GROUP BY 
    A.AUTHOR_ID, A.AUTHOR_NAME, B.CATEGORY
ORDER BY 
    A.AUTHOR_ID ASC,
    B.CATEGORY DESC;