[SQL]프로그래머스 Lv3. 카테고리 별 도서 판매량 집계하기

SELECT A.CATEGORY,
        SUM(B.SALES) "TOTAL_SALES"
FROM BOOK A INNER JOIN BOOK_SALES B ON A.BOOK_ID = B.BOOK_ID
WHERE B.SALES_DATE LIKE '%2022-01%'
GROUP BY 1
ORDER BY 1