Perguntas query para somar um campo texto

WITH ValList AS(
        SELECT  E4_CODIGO,
                CAST(LEFT(RTRIM(E4_COND),CASE WHEN PATINDEX('%,%', RTRIM(E4_COND)) = 0 THEN 50 ELSE PATINDEX('%,%', RTRIM(E4_COND)) - 1 END) AS FLOAT) Val,
                RIGHT(RTRIM(E4_COND),LEN(RTRIM(E4_COND)) - PATINDEX('%,%', RTRIM(E4_COND))) Remainder--, RTRIM(E4_COND), LEN(RTRIM(E4_COND)), PATINDEX('%,%', RTRIM(E4_COND)), RIGHT(RTRIM(E4_COND),5)
        FROM    SE4010 --WHERE RTRIM(E4_COND) LIKE '%,%'
        UNION ALL
        SELECT  E4_CODIGO,
                CAST(LEFT(Remainder,CASE WHEN PATINDEX('%,%', Remainder) = 0 THEN LEN(Remainder) ELSE PATINDEX('%,%', Remainder) - 1 END) AS FLOAT) Val,
                RIGHT(Remainder,CASE WHEN PATINDEX('%,%', Remainder) = 0 THEN 0 ELSE LEN(Remainder) - PATINDEX('%,%', Remainder) END) Remainder
        FROM    ValList
        WHERE   LEN(Remainder) > 0

)
SELECT  E4_CODIGO,
        SUM(Val)
FROM    ValList
GROUP BY E4_CODIGO

WITH ValList AS(
SELECT E4_CODIGO,
CAST(LEFT(RTRIM(E4_COND),CASE WHEN PATINDEX('%,%', RTRIM(E4_COND)) = 0 THEN 50 ELSE PATINDEX('%,%', RTRIM(E4_COND)) - 1 END) AS FLOAT) Val,
RIGHT(RTRIM(E4_COND),LEN(RTRIM(E4_COND)) - PATINDEX('%,%', RTRIM(E4_COND))) Remainder--, RTRIM(E4_COND), LEN(RTRIM(E4_COND)), PATINDEX('%,%', RTRIM(E4_COND)), RIGHT(RTRIM(E4_COND),5)
FROM SE4010 --WHERE RTRIM(E4_COND) LIKE '%,%'
UNION ALL
SELECT E4_CODIGO,
CAST(LEFT(Remainder,CASE WHEN PATINDEX('%,%', Remainder) = 0 THEN LEN(Remainder) ELSE PATINDEX('%,%', Remainder) - 1 END) AS FLOAT) Val,
RIGHT(Remainder,CASE WHEN PATINDEX('%,%', Remainder) = 0 THEN 0 ELSE LEN(Remainder) - PATINDEX('%,%', Remainder) END) Remainder
FROM ValList
WHERE LEN(Remainder) > 0

)
UPDATE SE4010 SET E4_MITDIAS = TOTAL
FROM SE4010 E4 INNER JOIN 
(SELECT E4_CODIGO,
SUM(Val) AS TOTAL
FROM ValList  
GROUP BY E4_CODIGO) VL ON VL.E4_CODIGO = E4.E4_CODIGO AND D_E_L_E_T_ <> '*' AND E4.E4_FILIAL ='01'