Home Database Mysql Tutorial MySQL修改表结构操作命令总结

MySQL修改表结构操作命令总结

Jun 07, 2016 pm 04:27 PM
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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 perso

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;

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