分区裁剪

explain plan for select /*+leading (T6) use_nl( T1 T6)*/ * from T_PM_ACCT_DTL_AF T1,(SELECT 
                *
                 FROM S_PM_MGR_DEPT_RELA A
                WHERE DEPT1_CODE <> '999999999') T6
      where T1.MGR_CODE = T6.MGR_CODE
      and t1.data_date>20130101;
select * from table(dbms_xplan.display());

Plan hash value: 3887218478
 
---------------------------------------------------------------------------------------------------------------
| Id  | Operation                | Name               | Rows  | Bytes | Cost (%CPU)| Time     | Pstart| Pstop |
---------------------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT         |                    |  1173M|   358G|    52G  (2)|999:59:59 |       |       |
|   1 |  NESTED LOOPS            |                    |  1173M|   358G|    52G  (2)|999:59:59 |       |       |
|*  2 |   TABLE ACCESS FULL      | S_PM_MGR_DEPT_RELA |  6303 |   683K|    45   (0)| 00:00:01 |       |       |
|   3 |   PARTITION LIST ITERATOR|                    |   186K|    38M|  8354K  (2)| 27:50:58 |   KEY |   KEY |
|*  4 |    TABLE ACCESS FULL     | T_PM_ACCT_DTL_AF   |   186K|    38M|  8354K  (2)| 27:50:58 |   KEY |   KEY |
---------------------------------------------------------------------------------------------------------------
 
Predicate Information (identified by operation id):
---------------------------------------------------
 
   2 - filter("DEPT1_CODE"<>'999999999')
   4 - filter("T1"."MGR_CODE"="A"."MGR_CODE")

key key  Oracle不知道要扫描那些分区,动态分区裁剪

explain plan for select * from T_PM_ACCT_DTL_AF t1 
where t1.data_date='20130101';
select * from table(dbms_xplan.display());

Plan hash value: 1825735905
 
----------------------------------------------------------------------------------------------------------
| Id  | Operation             | Name             | Rows  | Bytes | Cost (%CPU)| Time     | Pstart| Pstop |
----------------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT      |                  |  1312K|   267M|  9232   (2)| 00:01:51 |       |       |
|   1 |  PARTITION LIST SINGLE|                  |  1312K|   267M|  9232   (2)| 00:01:51 |   KEY |   KEY |
|   2 |   TABLE ACCESS FULL   | T_PM_ACCT_DTL_AF |  1312K|   267M|  9232   (2)| 00:01:51 |   368 |   368 |
----------------------------------------------------------------------------------------------------------

原文地址:https://www.cnblogs.com/hzcya1995/p/13352351.html