select  a.itm,  b.wse, c.id,  a.descr_1, a.itm_type,  a.ed_date, b.scode from cnum a, ariscode b, dmf c where a.itm = b.itm and b.wse = c.wse;

call     count       cpu    elapsed       disk      query    current        rows
------- ------  -------- ---------- ---------- ---------- ----------  ----------
Parse        1      0.01       0.00          0         12          0           0
Execute      1      0.00       0.00          0          0          0           0
Fetch      733      0.15       1.48        856       9245          0       10969
------- ------  -------- ---------- ---------- ---------- ----------  ----------
total      735      0.17       1.48        856       9257          0       10969

Misses in library cache during parse: 1
Optimizer mode: ALL_ROWS
Parsing user id: 75  (TEST)

Rows     Row Source Operation
-------  ---------------------------------------------------
  10969  HASH JOIN  (cr=9245 pr=856 pw=0 time=1127898 us)
  10969   MERGE JOIN  (cr=4076 pr=387 pw=0 time=868260 us)
      4    TABLE ACCESS BY INDEX ROWID dmf (cr=2 pr=0 pw=0 time=67 us)
      4     INDEX FULL SCAN dmf_PK (cr=1 pr=0 pw=0 time=36 us)(object id 67101)
  10969    SORT JOIN (cr=4074 pr=387 pw=0 time=857253 us)
  10969     TABLE ACCESS BY INDEX ROWID ARISCODE (cr=4074 pr=387 pw=0 time=634439 us)
  10969      INDEX FULL SCAN ARISCODE__WSE__IDX (cr=40 pr=38 pw=0 time=5363 us)(object id 65665)
  10205   TABLE ACCESS BY INDEX ROWID CNUM (cr=5169 pr=469 pw=0 time=142954 us)
  10205    INDEX FULL SCAN CNUM_PK (cr=757 pr=25 pw=0 time=24128 us)(object id 65587)


Rows     Execution Plan
-------  ---------------------------------------------------
      0  SELECT STATEMENT   MODE: ALL_ROWS
  10969   HASH JOIN
  10969    MERGE JOIN
      4     TABLE ACCESS   MODE: ANALYZED (BY INDEX ROWID) OF 'dmf' 
                (TABLE)
      4      INDEX   MODE: ANALYZED (FULL SCAN) OF 'dmf_PK' (INDEX 
                 (UNIQUE))
  10969     SORT (JOIN)
  10969      TABLE ACCESS   MODE: ANALYZED (BY INDEX ROWID) OF 'ARISCODE' 
                 (TABLE)
  10969       INDEX   MODE: ANALYZED (FULL SCAN) OF 
                  'ARISCODE__WSE__IDX' (INDEX)
  10205    TABLE ACCESS   MODE: ANALYZED (BY INDEX ROWID) OF 'CNUM' (TABLE)

  10205     INDEX   MODE: ANALYZED (FULL SCAN) OF 'CNUM_PK' (INDEX 
                (UNIQUE))


Elapsed times include waiting on following events:
  Event waited on                             Times   Max. Wait  Total Waited
  ----------------------------------------   Waited  ----------  ------------
  SQL*Net message to client                     733        0.00          0.00
  db file sequential read                       856        0.02          1.29
  SQL*Net message from client                   733        0.12         12.18

SELECT a.itm,
       b.wse,
       c.ID,
       a.descr_1,
       a.itm_type,
       a.ed_date,
       b.scode
FROM   cnum a,
       ariscode b,
       dmf c
WHERE  a.itm = b.itm
       AND b.wse = c.wse;