select
  MAX(CHECKUP_DATE) AS CK_DATE
  ,SUB2.MEMBER_CODE AS CODE
  ,MMB2.LAST_NAME || MMB2.FIRST_NAME AS NAME
  ,ROUND(MAX(WEIGHT1) - MAX(WEIGHT2),1) AS CHG_WT
from
  (
    select
      MEMBER_CODE
      ,ROWNUM
      ,CHECKUP_DATE
      ,CASE WHEN ROWNUM = 1 THEN WEIGHT ELSE 0 END AS WEIGHT1
      ,CASE WHEN ROWNUM = 2 THEN WEIGHT ELSE 0 END AS WEIGHT2
    from
    (
      select
        ROW_NUMBER() OVER(PARTITION BY MMB.MEMBER_CODE) AS ROWNUM
        ,MMB.MEMBER_CODE AS MEMBER_CODE
        ,HLT.CHECKUP_DATE AS CHECKUP_DATE
        ,HLT.WEIGHT AS WEIGHT
      from
        HEALTH_CHECKUP HLT
        inner join 
          MEMBER_MST MMB
          on MMB.MEMBER_CODE = HLT.MEMBER_CODE
      order by
        MMB.MEMBER_CODE DESC,HLT.CHECKUP_DATE DESC
    ) AS SUB1
    where
     ROWNUM <= 2
  ) AS SUB2
  inner join
    MEMBER_MST MMB2
    on
      SUB2.MEMBER_CODE = MMB2.MEMBER_CODE
group by
  CODE
having
  ABS(CHG_WT) >= 5
order by
  CHG_WT desc,CODE desc