SQL statement taking a long time

Question

Hi friends,
The below query is taking a very long time to execute. Please give some advise to optimise it.
INSERT INTO AFMS_ATT_DETL
    ATT_NUM,
    ATT_REF_CD,
    ATT_REF_TYP_CD,
    ATT_DOC_CD,
    ATT_FILE_NAM,
    ATT_FILE_VER_NUM_TXT,
    ATT_DOC_LIB_NAM,
    ATT_DESC_TXT,
    ATT_TYP_CD,
    ACTIVE_IND,
    CRT_BY_USR_NUM,
    CRT_DTTM,
    UPD_BY_USR_NUM,
    UPD_DTTM ,
    APP_ACC_CD,
    ARCH_CRT_BTCH_NUM,
        ARCH_CRT_DTTM,
    ARCH_UPD_BTCH_NUM ,
        ARCH_UPD_DTTM
  (SELECT
    K.ATT_NUM,
    K.ATT_REF_CD,
    K.ATT_REF_TYP_CD,
    K.ATT_DOC_CD,
    K.ATT_FILE_NAM,
    K.ATT_FILE_VER_NUM_TXT,
    K.ATT_DOC_LIB_NAM,
    K.ATT_DESC_TXT,
    K.ATT_TYP_CD,
    K.ACTIVE_IND,
    K.CRT_BY_USR_NUM,
    K.CRT_DTTM,
    K.UPD_BY_USR_NUM,
    K.UPD_DTTM ,
    L_APP_ACC_CD1,
    L_ARCH_BTCH_NUM,
    SYSDATE ,
    L_ARCH_BTCH_NUM ,
    SYSDATE
    FROM
        FMS_ATT_DETL K
    WHERE
     ( K.ATT_REF_CD IN
         (SELECT CSE_CD FROM T_AFMS_CSE_DETL  )  AND
        K.ATT_REF_TYP_CD ='ATTREF03'
     ) OR
         ATT_REF_CD IN
         (SELECT TO_CHAR(CMNT_PROC_NUM) FROM AFMS_CMNT_PROC ) AND
              ATT_REF_TYP_CD = 'ATTREF02'
         )    OR
         ATT_REF_CD IN
         (SELECT TO_CHAR(CSE_RPLY_NUM) FROM AFMS_CSE_RPLY ) AND
              ATT_REF_TYP_CD = 'ATTREF01'
    AND NOT EXISTS (SELECT ATT_NUM FROM (
      SELECT B.CSE_RPLY_NUM CSE_RPLY_NUM,B.ATT_NUM ATT_NUM FROM
        FMS_CSE_RPLY_ATT_MAP B
      WHERE
      NOT EXISTS
         (SELECT A.CSE_RPLY_NUM CSE_RPLY_NUM FROM AFMS_CSE_RPLY A WHERE A.CSE_RPLY_NUM  = B.CSE_RPLY_NUM)
    ) X WHERE X.ATT_NUM = K.ATT_NUM)
   ) ;

Answer 1

The explain plan for above query is as below:
PLAN_TABLE_OUTPUT
Plan hash value: 871385851
| Id  | Operation                | Name                    | Rows  | Bytes | Cos
t (%CPU)| Time     |
|   0 | INSERT STATEMENT         |                         |     9 |  1188 | 6  (17)| 00:00:01 |
|   1 |  LOAD TABLE CONVENTIONAL | AFMS_ATT_DETL           |       |       |        |          |
|*  2 |   FILTER                 |                         |       |       |        |          |
|*  3 |    HASH JOIN RIGHT ANTI  |                         |   167 | 22044 | 6  (17)| 00:00:01 |
|   4 |     VIEW                 | VW_SQ_1                 |     1 |    13 | 1   (0)| 00:00:01 |
|   5 |      NESTED LOOPS ANTI   |                         |     1 |    12 | 1   (0)| 00:00:01 |
|   6 |       INDEX FULL SCAN    | FMS_CSE_RPLY_ATT_MAP_PK |    25 |   200 | 1   (0)| 00:00:01 |
|*  7 |       INDEX UNIQUE SCAN  | AFMS_CSE_RPLY_PK        |   162 |   648 | 0   (0)| 00:00:01 |
|   8 |     TABLE ACCESS FULL    | FMS_ATT_DETL            |   167 | 19873 | 4   (0)| 00:00:01 |
|*  9 |    INDEX UNIQUE SCAN     | T_AFMS_CSE_DETL_PK      |     1 |     9 | 0   (0)| 00:00:01 |
|* 10 |    INDEX FULL SCAN       | AFMS_CSE_RPLY_PK        |     1 |     4 | 1   (0)| 00:00:01 |
|* 11 |    INDEX FULL SCAN       | AFMS_CMNT_PROC_PK       |     1 |     5 | 1   (0)| 00:00:01 |
Predicate Information (identified by operation id):
   2 - filter("K"."ATT_REF_TYP_CD"='ATTREF03' AND  EXISTS (SELECT 0 FROM "T_AFMS_CSE_DETL"
              "T_AFMS_CSE_DETL" WHERE "CSE_CD"=:B1) OR "ATT_REF_TYP_CD"='ATTREF01' AND  EXISTS (SELECT 0
              FROM "AFMS_CSE_RPLY" "AFMS_CSE_RPLY" WHERE TO_CHAR("CSE_RPLY_NUM")=:B2) OR
              "ATT_REF_TYP_CD"='ATTREF02' AND  EXISTS (SELECT 0 FROM "AFMS_CMNT_PROC" "AFMS_CMNT_PROC"
              WHERE TO_CHAR("CMNT_PROC_NUM")=:B3))
   3 - access("ITEM_1"="K"."ATT_NUM")
   7 - access("A"."CSE_RPLY_NUM"="B"."CSE_RPLY_NUM")
   9 - access("CSE_CD"=:B1)
  10 - filter(TO_CHAR("CSE_RPLY_NUM")=:B1)
  11 - filter(TO_CHAR("CMNT_PROC_NUM")=:B1)