mysql 添加分区（分区增删改）

      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： 
        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

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)
);

        插入测试数据

INSERT INTO tr VALUES
(1, 'desk organiser', '2003-10-15'),
(2, 'CD player', '1993-11-05'),
(3, 'TV set', '1996-03-10'),
(4, 'bookcase', '1982-01-10'),
(5, 'exercise bike', '2004-05-09'),
(6, 'sofa', '1987-06-05'),
(7, 'popcorn maker', '2001-11-22'),
(8, 'aquarium', '1992-08-04'),
(9, 'study desk', '1984-09-16'),
(10, 'lava lamp', '1998-12-25');

        查询P2中的数据

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

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 

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 

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 

ALTER TABLE members ADD PARTITION (PARTITION p3 VALUES LESS THAN (2000));

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) */