CTE 를 이용한 BOM 전개

WITH BOM_CTE(P_ITEM_CD, C_ITEM_CD, LEVEL)
AS
(
    SELECT T.P_ITEM_CD, T.C_ITEM_CD, 1 AS LEVEL
 FROM bba020t_2 T
 WHERE T.P_ITEM_CD in ('HU3723-V')

    UNION ALL
 SELECT C.P_ITEM_CD, C.C_ITEM_CD, LEVEL+1
 FROM bba020t_2 C
 INNER JOIN BOM_CTE P
 ON C.P_ITEM_CD = P.C_ITEM_CD
 --WHERE C.P_ITEM_CD in ('HU3723-V')
)
SELECT P_ITEM_CD, C_ITEM_CD, MAX(LEVEL) AS LEVEL
FROM BOM_CTE
--WHERE P_ITEM_CD in ('HU3723-V')
GROUP BY P_ITEM_CD, C_ITEM_CD
ORDER BY P_ITEM_CD ASC
OPTION(MAXRECURSION 3)