SQL> select t1.* from t1,t2 where t1.object_id=t2.object_id;
99 rows selected.
Execution Plan
----------------------------------------------------------
Plan hash value: 1506669289
--------------------------------------------------------------------------------
-------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Tim
e |
--------------------------------------------------------------------------------
-------
| 0 | SELECT STATEMENT | | 99 | 16929 | 201 (0)| 00:
00:03 |
| 1 | NESTED LOOPS | | 99 | 16929 | 201 (0)| 00:
00:03 |
| 2 | NESTED LOOPS | | 99 | 16929 | 201 (0)| 00:
00:03 |
| 3 | TABLE ACCESS FULL | T2 | 99 | 1287 | 3 (0)| 00:
00:01 |
|* 4 | INDEX RANGE SCAN | IDX_T1 | 1 | | 1 (0)| 00:
00:01 |
| 5 | TABLE ACCESS BY INDEX ROWID| T1 | 1 | 158 | 2 (0)| 00:
00:01 |
--------------------------------------------------------------------------------
-------
Predicate Information (identified by operation id):
---------------------------------------------------
4 - access("T1"."OBJECT_ID"="T2"."OBJECT_ID")
Note
-----
- dynamic sampling used for this statement (level=2)
Statistics
----------------------------------------------------------
8 recursive calls
0 db block gets
135 consistent gets
4 physical reads
0 redo size
6108 bytes sent via SQL*Net to client
589 bytes received via SQL*Net from client
8 SQL*Net roundtrips to/from client
0 sorts (memory)
0 sorts (disk)
99 rows processed
【测试】在hr用户下自行创建T1和T2表写一条SQL语句,(NL连接)
原文:http://www.cnblogs.com/tomatoes-/p/5971009.html