SQL> desc emp_Atn_03;
 Name                            Null?    Type
 ------------------------------- -------- ----
 TRN_IDE                         NOT NULL NUMBER
 BAS_COD                         NOT NULL NUMBER
 ATN_DTE                         NOT NULL DATE
 UNT_COD                         NOT NULL NUMBER
 DPT_COD                         NOT NULL NUMBER
 SFT_COD                         NOT NULL NUMBER
 ATN_TYP                                  NUMBER
 INN_TIM                                  DATE
 CR_ID                                    NUMBER
 CR_DT                                    DATE
 AP_ID                                    NUMBER
 AP_DT                                    DATE

SQL> desc emp_Atn_04
 Name                            Null?    Type
 ------------------------------- -------- ----
 TRN_IDE                         NOT NULL NUMBER
 BAS_COD                         NOT NULL NUMBER
 EMP_COD                         NOT NULL NUMBER
 DSG_COD                                  NUMBER
 EMP_ATN                         NOT NULL CHAR(3)
 EMP_LEV                                  CHAR(10)
 TOT_ATN                         NOT NULL CHAR(3)
 CHG_DSG                                  NUMBER
 CHG_SFT                                  NUMBER
 ORD_COD                                  NUMBER
 LIN_NUM                                  NUMBER
 SRL_NUM                                  NUMBER

INDEXES ON EMP_ATN_03
 	Index Name	Unique?	Column Name	Order	Position	Index Owner

	EMP_ATN_03_PK	Y	TRN_IDE	Asc	1	SAL
	EMP_ATN_03_PK	Y	BAS_COD	Asc	2	SAL
	EMP_ATN_03_UK	Y	ATN_DTE	Asc	1	SAL
	EMP_ATN_03_UK	Y	ATN_TYP	Asc	2	SAL
	EMP_ATN_03_UK	Y	UNT_COD	Asc	3	SAL
	EMP_ATN_03_UK	Y	DPT_COD	Asc	4	SAL
	EMP_ATN_03_UK	Y	SFT_COD	Asc	5	SAL

INSEXES OF EMP_ATN_04

 	Index Name	Unique?	Column Name	Order	Position	Index Owner

	EMP_ATN_04_PK	Y	TRN_IDE	Asc	1	SAL
	EMP_ATN_04_PK	Y	BAS_COD	Asc	2	SAL
	EMP_ATN_04_PK	Y	EMP_COD	Asc	3	SAL

SELECT DISTINCT TO_CHAR (atn_dte, 'dd') atn_dte, a4.emp_cod, emp_nam, emp_fnm,
                dsg_des, tot_atn, a4.ord_cod, a4.lin_num, a3.unt_cod, unt_des,
                dpt_des,
                DECODE (sft_cod,
                        1, 'A',
                        2, 'B',
                        3, 'C',
                        4, 'G',
                        5, 'R'
                       ) sft_des,
                apt_dte, a4.bas_cod, sft_cod,
                DECODE (RTRIM (tot_atn),
                        'P', 1,
                        'G', sal.val_guz_pay (a4.emp_cod,
                                              a4.bas_cod,
                                              a3.atn_dte,
                                              a4.tot_atn
                                             ),
                        'P/2', 0.50,
                        'ML', 1,
                        'CL', 1,
                        'AL', 1,
                        0
                       ) pay_dys,
                DECODE (NVL (chg_dsg, 0), 0, 0, 1) chg_dsg, a3.dpt_cod
           FROM sal.emp_atn_03 a3,
                sal.emp_atn_04 a4,
                sal.emp_fil_01 emp_fil,
                sal.emp_dsg_01 emp_dsg,
                sal.dsg_00_01 dsg,
                sal.unt_00_01 u,
                sal.dpt_00_01 d
          WHERE a3.trn_ide = a4.trn_ide
            AND a3.bas_cod = a4.bas_cod
            AND emp_fil.emp_cod = a4.emp_cod
            AND emp_fil.bas_cod = a4.bas_cod
            AND emp_dsg.emp_cod = a4.emp_cod
            AND emp_dsg.bas_cod = a4.bas_cod
            AND emp_fil.cat_cod =1
            AND dsg.dsg_cod = emp_dsg.dsg_cod
            AND u.unt_cod = a3.unt_cod
            AND d.dpt_cod = a3.dpt_cod
            AND atn_dte BETWEEN emp_dsg.frm_dte
                            AND DECODE (emp_dsg.too_dte,
                                        NULL, TRUNC (SYSDATE),
                                        too_dte
                                       )
            AND a3.unt_cod BETWEEN 8 AND 40
            AND a4.emp_cod BETWEEN 0 AND 99999999
            AND atn_dte BETWEEN '01-DEC-2008' AND '31-DEC-2008'
       ORDER BY a3.unt_cod,
                sft_cod,
                atn_dte,
                dpt_cod,
                a4.lin_num,
                a4.ord_cod,
                apt_dte

Select lpad(' ',2*(level-1))||operation||' '||options||' '||object_name 
     ||' '||decode(id,0,'Cost = '||position) "Query Plan" 
   From plan_table 
   Start with id = 0  
   connect by prior id = parent_id 

Query Plan

SELECT STATEMENT   Cost = 
  SORT GROUP BY  
    NESTED LOOPS   
      TABLE ACCESS BY INDEX ROWID EMP_ATN_03 
        INDEX RANGE SCAN EMP_ATN_03_UK 
      TABLE ACCESS BY INDEX ROWID EMP_ATN_04 
        INDEX RANGE SCAN EMP_ATN_04_PK