Query is slow...need tuning

Question

Hi all
I am using 11g database and this query is a part of a cursor declaration...Is there any scope for optimisation in this query? I appreciate your answers
WITH
         ESN_GENEALOGY AS
        (SELECT DISTINCT G.SerialNo FROM  GENEALOGY G
                                    INNER JOIN PRODUCT P ON G.PRODUCTID=P.ID
                                    WHERE G.LASTARCHIVEDBY=I_SerialNo AND G.ACTIVE=1 AND P.PRODUCTINVENTORYTYPE=102 UNION SELECT I_SerialNo AS SerialNo FROM DUAL)
        SELECT ListParentProductID, ListCompProductNo, ListCompProductID, ListCompQuantity AS SBQty,SERIALNO,WOPRODUCTID,WORKORDERNO
        FROM
        SELECT BM.PARENTPRODUCTID ListParentProductID,BM.PRODUCTNO ListCompProductNo,BM.PRODUCTID ListCompProductID,
        BM.QUANTITY ListCompQuantity,BM.SERIALNO,SN.PRODUCTID WOPRODUCTID,SN.WORKORDERNO,I_SerialNo SN
        FROM
        (SELECT PARENTPRODUCTID,PRODUCTNO,PRODUCTID,SUM(QUANTITY) AS QUANTITY,SERIALNO
        FROM
        SELECT PARENTPRODUCTID,PRODUCTNO,PRODUCTID,QUANTITY,SERIALNO
        FROM
        SELECT
        (CASE WHEN PC1.LASTARCHIVEDBY IS NULL THEN P1.ID ELSE P3.ID END) AS  PARENTPRODUCTID,
        P2.PRODUCTNO AS PRODUCTNO,
        P2.ID AS PRODUCTID,
        SUM(C1.QUANTITY) AS QUANTITY,
        (CASE WHEN PC1.LASTARCHIVEDBY IS NULL THEN I_SerialNo ELSE CG.SERIALNO END) AS  SERIALNO
        FROM WIP_ORDER WO
        INNER JOIN PRODUCT_COMPONENT PC ON (
        PC.PRODUCTID = WO.PRODUCTID
        AND wo.wiporderno =I_WipOrderNo
        INNER JOIN COMPONENT C on C.ID = PC.COMPONENTID
        INNER JOIN PRODUCT P1 on (
        P1.ID = C.PRODUCTID
        AND C.EFFECTIVEDATE <= WO.SCHEDULEDSTARTDATE
        AND (C.DISCONTINUEDATE > WO.SCHEDULEDSTARTDATE or C.DISCONTINUEDATE is null)
        INNER JOIN PRODUCT P on WO.PRODUCTID = P.ID
        INNER JOIN PRODUCT_COMPONENT PC1 on  PC1.PRODUCTID = C.PRODUCTID
        INNER JOIN COMPONENT C1 on ( C1.ID = PC1.COMPONENTID
        AND C1.EFFECTIVEDATE <= WO.SCHEDULEDSTARTDATE
        AND (C1.DISCONTINUEDATE > WO.SCHEDULEDSTARTDATE OR C1.DISCONTINUEDATE is null)
        INNER JOIN PRODUCT P2 on P2.ID = C1.PRODUCTID
        LEFT JOIN PRODUCT P3 ON PC1.LASTARCHIVEDBY=P3.PRODUCTNO
        LEFT JOIN  (SELECT DISTINCT G.SERIALNO, G.PRODUCTID FROM  GENEALOGY G
                                    INNER JOIN PRODUCT P ON G.PRODUCTID=P.ID
                                    WHERE G.LASTARCHIVEDBY=I_SerialNo AND G.ACTIVE=1 AND P.PRODUCTINVENTORYTYPE=102) CG ON  P3.ID=CG.PRODUCTID
        WHERE  (CASE WHEN PC1.LASTARCHIVEDBY IS NULL THEN I_SerialNo ELSE CG.SERIALNO END) IS NOT NULL
        GROUP BY   (CASE WHEN PC1.LASTARCHIVEDBY IS NULL THEN P1.ID ELSE P3.ID END) , P2.PRODUCTNO, P2.ID,
                        (CASE WHEN PC1.LASTARCHIVEDBY IS NULL THEN I_SerialNo ELSE CG.SERIALNO END)
        ) set1
        UNION ALL
        SELECT PARENTPRODUCTID,PRODUCTNO,PRODUCTID,QUANTITY*(-1) AS QUANTITY,SERIALNO
        FROM
        SELECT   A.ParentProductID,
        A.ProductNO,
        A.ProductID,
        SUM(A.Quantity) AS Quantity,
        A.SERIALNO
        FROM (
        SELECT  G.PARENTPRODUCTID,
        P.PRODUCTNO,
        G.PRODUCTID,
        G.QUANTITY,
        G.ID,
        G.LASTARCHIVEDBY AS SERIALNO
        FROM GENEALOGY G
        INNER JOIN PRODUCT P ON G.PRODUCTID=P.ID
        WHERE   G.LASTARCHIVEDBY IN(SELECT SERIALNO FROM  ESN_GENEALOGY) AND G.ACTIVE=1
        UNION
        SELECT
        ParentPartID PARENTPRODUCTID,
        P.PRODUCTNO,
        ORIGINALPARTID PRODUCTID,
        QUANTITY QUANTITY,
        P.ID,
        BDH.SERIALNO AS SERIALNO
        FROM COB_T_BOM_DEVIATION_HISTORY BDH
        INNER JOIN PRODUCT p ON P.id = BDH.ORIGINALPARTID
        WHERE BDH.SERIALNO IN(SELECT SERIALNO FROM  ESN_GENEALOGY)
        UNION           
        SELECT
        ParentPartID PARENTPRODUCTID,
        P.PRODUCTNO,
        DEVIATIONPARTID PRODUCTID,
        -1 * QUANTITY QUANTITY,
        P.ID,
        BDH.SERIALNO AS SERIALNO
        FROM COB_T_BOM_DEVIATION_HISTORY BDH
        INNER JOIN PRODUCT p ON P.id = BDH.DEVIATIONPARTID
        WHERE BDH.SERIALNO IN(SELECT SERIALNO FROM  ESN_GENEALOGY)
        union
        SELECT ESB.PARENTPRODUCTID PARENTPRODUCTID,
        COMPONENTPARTNUMBER PRODUCTNO,
        COMPONENTPRODUCTID PRODUCTID,
        QUANTITY,
        ESB.ID,
        ESB.SERIALNO AS SERIALNO
        FROM COB_T_ENGINE_SHORT_BUILD ESB
        where  ESB.SERIALNO IN(SELECT SERIALNO FROM  ESN_GENEALOGY)
        ) A
        WHERE QUANTITY <> 0 AND SERIALNO IS NOT NULL
        GROUP BY  PARENTPRODUCTID, PRODUCTNO, PRODUCTID,SERIALNO   
        ) set2
        ) GROUP BY PARENTPRODUCTID,PRODUCTNO,PRODUCTID,SERIALNO
        ) BM
        LEFT JOIN  COB_T_SERIAL_NO SN  ON  BM.SERIALNO=SN.SERIALNO
        )BOM
        WHERE ListCompQuantity <> 0;

Answer 1

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