select
 chg.date2 as ck_date,
 mst.member_code as code,
 mst.last_name || mst.first_name as name,
 chg.CHG_WT as chg_wt
from member_mst as mst
left join (
select 
tb1.CHECKUP_DATE date1
, tb2.CHECKUP_DATE date2
, tb1.MEMBER_CODE
, round(tb2.WEIGHT - tb1.WEIGHT, 1) as CHG_WT
from health_checkup as tb1
left join health_checkup as tb2
on tb1.member_code = tb2.member_code 
and tb1.checkup_date < tb2.checkup_date
where date2 is not null
) chg
on mst.member_code = chg.member_code
where chg.CHG_WT >= 5 or chg.CHG_WT <= -5