[프로그래머스] Lv4. 저자 별 카테고리 별 매출액 집계하기

https://school.programmers.co.kr/learn/courses/30/lessons/144856

프로그래머스

문제

 

정답코드

SELECT A.author_id, A.author_name, B.category,
    SUM(BS.sales * B.price) AS 'TOTAL_SALES'
FROM book B JOIN author A ON B.author_id = A.author_id
    JOIN book_sales BS ON B.book_id = BS.book_id
WHERE sales_date LIKE '2022-01%'
GROUP BY B.author_id, B.category 
ORDER BY A.author_id, B.category DESC