SELECT 
A.max_date as CK_DATE,
A.m_code as CODE,
MEM.LAST_NAME || MEM.FIRST_NAME as NAME,
ROUND(A.weight - B.weight,1) as CHG_WT

FROM 
(SELECT MEMBER_CODE as m_code,
        MAX(CHECKUP_DATE) as max_date,
        WEIGHT as weight
    FROM HEALTH_CHECKUP 
    GROUP BY MEMBER_CODE)
A INNER JOIN
(SELECT MEMBER_CODE as m_code,
        MIN(CHECKUP_DATE) as min_date,
        WEIGHT as weight
    FROM HEALTH_CHECKUP
    GROUP BY MEMBER_CODE)
B ON A.m_code = B.m_code

INNER JOIN MEMBER_MST MEM
ON A.m_code = MEM.MEMBER_CODE

WHERE ABS(ROUND(A.weight - B.weight,1) ) >= 5
ORDER BY CHG_WT DESC,CODE DESC