MySql数据分区操作之新增分区操作

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) */
 

使用 reorganize partition进行数据的合并与拆分，数据是没有丢失的。
(详细出处参考：)
如果用此方式在之前添加会报错，只能用另一种合并拆分分区的方式操作。