如果想在已经建好的表上进行分区,如果使用alter添加分区的话,mysql会提示错误: 复制代码 代码如下: ERROR 1505 <HY000> Partition management on a not partitioned table is not possible
正确的方法是新建一个具有分区的表,结构一致,然后用insert into 分区表 select * from 原始表; 测试创建分区表文件 复制代码 代码如下: CREATE TABLE tr (id INT, name VARCHAR(50), purchased DATE) PARTITION BY RANGE(YEAR(purchased)) ( PARTITION p0 VALUES LESS THAN (1990), PARTITION p1 VALUES LESS THAN (1995), PARTITION p2 VALUES LESS THAN (2000), PARTITION p3 VALUES LESS THAN (2005) );
查询P2中的数据 复制代码 代码如下: select * from tr where purchased between "1995-01-01′ and "2004-12-31′;
如果删除P2,在删除P2分区的同时,也会将其下的所有数据删除 复制代码 代码如下: alter table tr drop partition p2; show create table tr; CREATE TABLE `tr` ( `id` int(11) DEFAULT NULL, `name` varchar(50) DEFAULT NULL, `purchased` date DEFAULT NULL ) ENGINE=MyISAM DEFAULT CHARSET=utf8 /*!50100 PARTITION BY RANGE (YEAR(purchased)) (PARTITION p0 VALUES LESS THAN (1990) ENGINE = MyISAM, PARTITION p1 VALUES LESS THAN (1995) ENGINE = MyISAM, PARTITION p3 VALUES LESS THAN (2005) ENGINE = MyISAM) */
再次插入数据时,会将原P2的数据插入至P3中 复制代码 代码如下: INSERT INTO tr VALUES (11, "pencil holder", "1995-07-12′); ALTER TABLE tr DROP PARTITION p3; SELECT * FROM tr WHERE purchased BETWEEN "1995-01-01′ AND "2004-12-31′;
创建一个新的测试表 复制代码 代码如下: CREATE TABLE members ( id INT, fname VARCHAR(25), lname VARCHAR(25), dob DATE ) PARTITION BY RANGE(YEAR(dob)) ( PARTITION p0 VALUES LESS THAN (1970), PARTITION p1 VALUES LESS THAN (1980), PARTITION p2 VALUES LESS THAN (1990) );
直接用alter table tablename add partition 方式再最后面添加分区 复制代码 代码如下: ALTER TABLE members ADD PARTITION (PARTITION p3 VALUES LESS THAN (2000));
复制代码 代码如下: ALTER TABLE members reorganize partition p0 into ( partition m0 values less than (1960), partition m1 values less than (1970) ); show create table members; CREATE TABLE `members` ( `id` int(11) DEFAULT NULL, `fname` varchar(25) DEFAULT NULL, `lname` varchar(25) DEFAULT NULL, `dob` date DEFAULT NULL ) ENGINE=MyISAM DEFAULT CHARSET=utf8 /*!50100 PARTITION BY RANGE (YEAR(dob)) (PARTITION m0 VALUES LESS THAN (1960) ENGINE = MyISAM, PARTITION m1 VALUES LESS THAN (1970) ENGINE = MyISAM, PARTITION p1 VALUES LESS THAN (1980) ENGINE = MyISAM, PARTITION p2 VALUES LESS THAN (1990) ENGINE = MyISAM, PARTITION p3 VALUES LESS THAN (2000) ENGINE = MyISAM) */