/* 틀린 풀이 */ 
SELECT CAR_ID, ROUND(AVERAGE_DURATION, 1) AS AVERAGE_DURATION
FROM (
    SELECT CAR_ID, AVG(DATEDIFF(START_DATE, END_DATE)) AS AVERAGE_DURATION
    FROM CAR_RENTAL_COMPANY_RENTAL_HISTORY
    GROUP BY CAR_ID
) AS AVG_DURATIONS
WHERE AVERAGE_DURATION >= 7
ORDER BY AVERAGE_DURATION DESC, CAR_ID DESC;

/* 틀린 풀이 */ 
SELECT CATEGORY, MAX(PRICE) AS MAX_PRICE, PRODUCT_NAME
FROM FOOD_PRODUCT
WHERE CATEGORY IN ('과자', '국', '김치', '식용유')
GROUP BY CATEGORY
ORDER BY PRICE DESC;

/* 틀린 풀이 */ 
SELECT A.TITLE,A.BOARD_ID,B.REPLY_ID,B.WRITER_ID,B.CONTENTS,
        DATE_FORMAT(B.CREATED_DATE, '%Y-%m-%d') AS CREATED_DATE
FROM USED_GOODS_BOARD AS A, USED_GOODS_REPLY AS B
WHERE DATE_FORMAT(A.CREATED_DATE, '%Y-%m') = '2022-10' AND B.CREATED_DATE LIKE '2022-10%' AND A.BOARD_ID = B.BOARD_ID
ORDER BY B.CREATED_DATE,A.TITLE;

SELECT
    A.TITLE,
    A.BOARD_ID,
    B.REPLY_ID,
    B.WRITER_ID,
    B.CONTENTS,
    DATE_FORMAT(B.CREATED_DATE, '%Y-%m-%d') AS CREATED_DATE
FROM
    USED_GOODS_BOARD A
JOIN
    USED_GOODS_REPLY B ON
    A.BOARD_ID = B.BOARD_ID
WHERE
    A.CREATED_DATE like '2022-10%'
ORDER BY
    CREATED_DATE,
    A.TITLE