执行计划中各字段各模块描述(三)

2014-11-24 08:53:45 · 作者: · 浏览: 1
on | Name | Starts | E-Rows | A-Rows | A-Time | Buffers | Reads |
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| 1 | NESTED LOOPS | | 1 | 1 | 1 |00:00:00.01 | 10 | 1 |
|* 2 | TABLE ACCESS FULL | EMP | 1 | 1 | 1 |00:00:00.01 | 8 | 0 |
| 3 | TABLE ACCESS BY INDEX ROWID| DEPT | 1 | 1 | 1 |00:00:00.01 | 2 | 1 |
|* 4 | INDEX UNIQUE SCAN | PK_DEPT | 1 | 1 | 1 |00:00:00.01 | 1 | 1 |
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Predicate Information (identified by operation id):
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2 - filter("E"."ENAME"='SMITH')
4 - access("E"."DEPTNO"="D"."DEPTNO")

Note
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- dynamic sampling used for this statement


26 rows selected.
三、总结
由上可知,在不同的情形下可以获得执行计划的不同信息,而不同信息则展现了SQL语句对应的不同情况,因此应根据具体的情形具体分析。