WITH latest_two_checkups AS (
    SELECT 
        MEMBER_CODE, 
        CHECKUP_DATE, 
        WEIGHT,
        ROW_NUMBER() OVER (PARTITION BY MEMBER_CODE ORDER BY CHECKUP_DATE DESC) AS row_num
    FROM HEALTH_CHECKUP
),
checkup_diffs AS (
    SELECT
        l1.CHECKUP_DATE AS CK_DATE,
        l1.MEMBER_CODE AS CODE,
        l1.WEIGHT - l2.WEIGHT AS CHG_WT
    FROM
        latest_two_checkups l1
    JOIN
        latest_two_checkups l2
    ON
        l1.MEMBER_CODE = l2.MEMBER_CODE
        AND l1.row_num = 1
        AND l2.row_num = 2
    WHERE
        ABS(l1.WEIGHT - l2.WEIGHT) >= 5
),
member_info AS (
    SELECT
        MEMBER_CODE AS CODE,
        LAST_NAME || FIRST_NAME AS NAME
    FROM MEMBER_MST
)
SELECT
    cd.CK_DATE,
    cd.CODE,
    mi.NAME,
    ROUND(cd.CHG_WT, 1) AS CHG_WT
FROM
    checkup_diffs cd
JOIN
    member_info mi
ON
    cd.CODE = mi.CODE
ORDER BY
    cd.CHG_WT DESC,
    cd.CODE DESC;