https://school.programmers.co.kr/learn/courses/30/lessons/144853 SELECT BOOK_ID, SUBSTRING_INDEX(PUBLISHED_DATE, 1, 10) FROM BOOK WHERE CATEGORY = '인문' AND SUBSTRING_INDEX(PUBLISHED_DATE, 1, 4) = 2021 ORDER BY PUBLISHED_DATE https://school.programmers.co.kr/learn/courses/30/lessons/151136 SELECT ROUND(AVG(DAILY_FEE), 0) AS AVERAGE_FEE FROM CAR_RENTAL_COMPANY_CAR WHERE CAR_TYPE = 'SUV' https://sc..