with st as (select 
max(checkup_date) as m1_cd
, MEMBER_CODE as CODE
, WEIGHT as we
from 
HEALTH_CHECKUP as h1
group by MEMBER_CODE)
, st2 as (
select 
max(h.checkup_date) as m2_cd
, CODE
, h.WEIGHT as we2
from HEALTH_CHECKUP as h join st on st.CODE = h.MEMBER_CODE
where st.m1_cd != h.checkup_date
group by st.CODE
)
-- select * from st2
-- select * from st
select 
m1_cd as CK_DATE
, st.CODE
, mm.LAST_NAME || mm.FIRST_NAME as NAME
, ROUND(st.we - st2.we2, 2) as CHG_WT
from st join st2 on st.CODE = st2.CODE join member_mst mm on st.CODE = mm.MEMBER_CODE
where abs(ROUND(st.we * 100) - ROUND(st2.we2 * 100)) >= 500
order by CHG_WT desc, st.CODE desc