WITH ranked_checkups AS (
  SELECT 
    MEMBER_CODE,
    CHECKUP_DATE,
    WEIGHT,
    ROW_NUMBER() OVER (PARTITION BY MEMBER_CODE ORDER BY CHECKUP_DATE DESC) AS rank
  FROM 
    HEALTH_CHECKUP
)
SELECT 
  c2.CHECKUP_DATE AS CK_DATE,
  c2.MEMBER_CODE AS CODE,
  m.LAST_NAME || ' ' || m.FIRST_NAME AS NAME,
  ROUND(c2.WEIGHT - c1.WEIGHT, 1) AS CHG_WT
FROM 
  ranked_checkups c1
  JOIN ranked_checkups c2 ON c1.MEMBER_CODE = c2.MEMBER_CODE AND c1.rank = 2 AND c2.rank = 1
  JOIN MEMBER_MST m ON c2.MEMBER_CODE = m.MEMBER_CODE
WHERE 
  ROUND(c2.WEIGHT - c1.WEIGHT, 1) >= 5
ORDER BY 
  CHG_WT DESC,
  CODE DESC;