WITH QRY_BASE AS
(
    SELECT 'P1'PRODUCT,'T1'TYPE_PROD,120 WEIGHT FROM DUAL
    UNION 
    SELECT 'P2'PRODUCT,'T2'TYPE_PROD,120 WEIGHT FROM DUAL
    UNION 
    SELECT 'P3'PRODUCT,'T2'TYPE_PROD,120 WEIGHT FROM DUAL
    UNION 
    SELECT 'P4'PRODUCT,'T1'TYPE_PROD,120 WEIGHT FROM DUAL
    UNION 
    SELECT 'P5'PRODUCT,'T2'TYPE_PROD,120 WEIGHT FROM DUAL
    UNION 
    SELECT 'P6'PRODUCT,'T2'TYPE_PROD,120 WEIGHT FROM DUAL
    UNION 
    SELECT 'P7'PRODUCT,'T2'TYPE_PROD,120 WEIGHT FROM DUAL
    UNION 
    SELECT 'P8'PRODUCT,'T1'TYPE_PROD,120 WEIGHT FROM DUAL
    UNION 
    SELECT 'P9'PRODUCT,'T2'TYPE_PROD,120 WEIGHT FROM DUAL
    UNION 
    SELECT 'P10'PRODUCT,'T2'TYPE_PROD,120 WEIGHT FROM DUAL
)
SELECT SUM(WEIGHT),
       SUM(WEIGHT)/(SELECT SUM(Q.WEIGHT) FROM QRY_BASE Q)*100 PERCENT_WEI
FROM QRY_BASE B WHERE B.TYPE_PROD='T1'

group by B.TYPE_PROD