这句为什么执行特别慢

SQL> select sum ( charges ) from inp_bill_detail where performed_by ='34' and rcpt_no >= '90031714' and rcpt_no <= '90032590' and item_class ='A' and ordered_by ='21'  ;Elapsed: 00:00:24.38Execution Plan
----------------------------------------------------------                                          
Plan hash value: 4038433501                                                                         
                                                                                                    
--------------------------------------------------------------------------------------              
| Id  | Operation          | Name            | Rows  | Bytes | Cost (%CPU)| Time     |              
--------------------------------------------------------------------------------------              
|   0 | SELECT STATEMENT   |                 |     1 |    33 | 49972   (3)| 00:10:00 |              
|   1 |  SORT AGGREGATE    |                 |     1 |    33 |            |          |              
|*  2 |   TABLE ACCESS FULL| INP_BILL_DETAIL |     1 |    33 | 49972   (3)| 00:10:00 |              
--------------------------------------------------------------------------------------              
                                                                                                    
Predicate Information (identified by operation id):                                                 
---------------------------------------------------                                                 
                                                                                                    
   2 - filter("PERFORMED_BY"='34' AND "ITEM_CLASS"='A' AND "ORDERED_BY"='21'                        
              AND "RCPT_NO">='90031714' AND "RCPT_NO"<='90032590')                                  
                                                                                                    
Note                                                                                                
-----                                                                                               
   - dynamic sampling used for this statement                                                       
Statistics
----------------------------------------------------------                                          
          0  recursive calls                                                                        
          0  db block gets                                                                          
     219060  consistent gets                                                                        
     208771  physical reads                                                                         
          0  redo size                                                                              
        417  bytes sent via SQL*Net to client                                                       
        396  bytes received via SQL*Net from client                                                 
          2  SQL*Net roundtrips to/from client                                                      
          0  sorts (memory)                                                                         
          0  sorts (disk)                                                                           
          1  rows processed