SQL> select count(*) from test;
Execution Plan
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Plan hash value: 1950795681
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| Id | Operation | Name | Rows | Cost (%CPU)| Time |
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| 0 | SELECT STATEMENT | | 1 | 193 (0)| 00:00:03 |
| 1 | SORT AGGREGATE | | 1 | | |
| 2 | TABLE ACCESS FULL| TEST | 1000 | 193 (0)| 00:00:03 |
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与计算的Cost相匹配，从实验种可以得出，在11gR2中，全表扫描计算Cost的方式依然和9i/10g一样，没有变化。