mysql修改表

表的结构如下:

mysql> show create table person;
| person | CREATE TABLE `person` (
  `number` int(11) DEFAULT NULL,
  `name` varchar(255) DEFAULT NULL,
  `birthday` date DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=utf8 |

删除列:

ALTER TABLE person DROP COLUMN birthday; 

添加列:

ALTER TABLE person ADD COLUMN birthday datetime;

修改列,把number修改为bigint:

ALTER TABLE person MODIFY number BIGINT NOT NULL;

或者是把number修改为id,类型为bigint:

ALTER TABLE person CHANGE number id BIGINT;

添加主键:

ALTER TABLE person ADD PRIMARY KEY (id);

删除主键:

ALTER TABLE person DROP PRIMARY KEY;

添加唯一索引:

ALTER TABLE person ADD UNIQUE name_unique_index (`name`);

为name这一列创建了唯一索引,索引的名字是name_unique_index.

添加普通索引:

ALTER TABLE person ADD INDEX birthday_index (`birthday`);

删除索引:

ALTER TABLE person DROP INDEX birthday_index;
ALTER TABLE person DROP INDEX name_unique_index;

禁用非唯一索引

ALTER TABLE person DISABLE KEYS;

ALTER TABLE...DISABLE KEYS让MySQL停止更新MyISAM表中的非唯一索引。

激活非唯一索引

ALTER TABLE person ENABLE KEYS;

ALTER TABLE ... ENABLE KEYS重新创建丢失的索引。

把表默认的字符集和所有字符列（CHAR, VARCHAR, TEXT）改为新的字符集:

ALTER TABLE person CONVERT TO CHARACTER SET utf8;

修改表某一列的编码

ALTER TABLE person CHANGE name name varchar(255) CHARACTER SET utf8;

仅仅改变一个表的默认字符集

ALTER TABLE person DEFAULT CHARACTER SET utf8;

 修改表名

RENAME TABLE person TO person_other;

移动表到其他数据库

RENAME TABLE current_db.tbl_name TO other_db.tbl_name;