Oracle 分区索引介绍和实例演示(4)
INDEX_NAME INDEX_TYPE TABLESPACE_NAME GLO PAR
------------------------------ --------------------------- ------------------------------ --- ---
BIG_TABLE_PK NORMAL TBS_TMP YES NO
SQL> set autot trace exp;
SQL> select * from big_table where id=1412;
Execution Plan
----------------------------------------------------------
Plan hash value: 2662411593
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| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time | Pstart| Pstop |
-------------------------------------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | 62 | 2 (0)| 00:00:01 | | |
| 1 | TABLE ACCESS BY GLOBAL INDEX ROWID| BIG_TABLE | 1 | 62 | 2 (0)| 00:00:01 | ROWID | ROWID |
|* 2 | INDEX UNIQUE SCAN | BIG_TABLE_PK | 1 | | 1 (0)| 00:00:01 | | |
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--如上，在其执行计划中，Pstart与Pstop都为ROWID
--出现了GLOBAL INDEX ROWID，我们添加主键时并未指定Global，但其执行计划表明执行了全局索引访问
--这个地方有待证实，对于分区表，非分区键上的主键或唯一索引是否一定是全局索引
SQL> drop index bita_created_date_i;
