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;
来源: https://www.php1.cn/detail/php-ad4aeab7c3.html