SELECT
checkup_date AS CK_DATE,
member_code AS CODE,
last_name || first_name AS NAME,
CHG_WT
FROM (
    SELECT
        member_code,
        checkup_date,
        weight,
        -- RANK() OVER(PARTITION BY member_code ORDER BY checkup_date DESC) AS checkup_date_rank
        ROUND(weight - LAG(weight, 1) OVER(PARTITION BY member_code ORDER BY checkup_date), 1) AS CHG_WT
    FROM health_checkup
)
LEFT JOIN member_mst USING(member_code)
WHERE CHG_WT IS NOT NULL AND ABS(CHG_WT) >= 5
ORDER BY CHG_WT DESC, CODE DESC