首页 / 数据库 / MySQL / Oracle 11g虚拟列上建分区
在Oracle 11g上,可以在虚拟列上做分区,这个特性还比较有用,下面来做一个测试:SQL> select * from v$version;BANNER
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Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
PL/SQL Release 11.2.0.1.0 - Production
CORE 11.2.0.1.0 Production
TNS for Linux: Version 11.2.0.1.0 - ProductionNLSRTL Version 11.2.0.1.0 - ProductionSQL> drop table test purge;
SQL> create table test
(bureau_code varchar2(20) not null,
province_code as (CAST(SUBSTR(bureau_code,0,2) AS VARCHAR2(2)))
)
partition by list (province_code)
(
partition p1 values ("01"),
partition p2 values ("02"),
partition p3 values ("03"),
partition p4 values ("04"),
partition p5 values ("05")
);SQL> insert into test(bureau_code) values("0101");
SQL> insert into test(bureau_code) values("0102");
SQL> insert into test(bureau_code) values("0202");
SQL> insert into test(bureau_code) values("0202");
SQL> insert into test(bureau_code) values("0302");
SQL> insert into test(bureau_code) values("0302");
SQL> insert into test(bureau_code) values("0402");
SQL> insert into test(bureau_code) values("0502");
SQL> commit;SQL> select * from test partition(p1);
BUREAU_CODE PR
-------------------- --
0101 01
0102 01SQL> set autotrace traceonly
SQL> select * from test partition(p1);
执行计划
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Plan hash value: 213508695
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| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time | Pstart| Pstop |
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| 0 | SELECT STATEMENT | | 2 | 30 | 4 (0)| 00:00:01 | | |
| 1 | PARTITION LIST SINGLE| | 2 | 30 | 4 (0)| 00:00:01 | 1 | 1 |
| 2 | TABLE ACCESS FULL | TEST | 2 | 30 | 4 (0)| 00:00:01 | 1 | 1 |--证明是走了分区的
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Note
-----
- dynamic sampling used for this statement (level=2)
统计信息
----------------------------------------------------------
0 recursive calls
0 db block gets
8 consistent gets
0 physical reads
0 redo size
434 bytes sent via SQL*Net to client
338 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
0 sorts (memory)
0 sorts (disk)
2 rows processed更多Oracle相关信息见Oracle 专题页面 http://www.linuxidc.com/topicnews.aspx?tid=12本文永久更新链接地址