MySQL用户和权限管理

MySQL用户和权限管理

用户和权限管理

Information about account privileges is stored in the user, db, host, tables_priv, columns_priv, and procs_priv tables
in the mysql database. The MySQL server reads the contents of these tables into memory when it
starts and reloads them under the circumstances. Access-control decisions are based on the
in-memory copies of the grant tables.

user: Contains user accounts, global privileges, and other non-privilege columns.
user: 用户帐号、全局权限

db: Contains database-level privileges.
db: 库级别权限

host: Obsolete.
host: 废弃

tables_priv: Contains table-level privileges.
表级别权限

columns_priv: Contains column-level privileges.
列级别权限

procs_priv: Contains stored procedure and function privileges.
存储过程和存储函数相关的权限

proxies_priv: Contains proxy-user privileges.
代理用户权限

用户帐号：
用户名@主机
用户名：16字符以内
主机：
主机名：www.chen.com, mysql
IP: 192.168.0.99
网络地址:
192.168.0.0/255.255.255.0

通配符：%，_
192.168.0.%
%.chen.com

--skip-name-resolve 略过名称解析

权限级别：
全局级别： SUPER、
库
表: DELETE, ALTER, TRIGGER
列: SELECT, INSERT, UPDATE
存储过程和存储函数

临时表：内存表
heap: 16MB
触发器：主动数据库
INSERT, DELETE, UPDATE
user: log

创建用户：
CREATE USER username@host [IDENTIFIED BY 'password']

GRANT ALL PRIVILEGES ON [object_type] priv_level TO username@'%' [WITH with_option ...];

object_type:
TABLE | FUNCTION | PROCEDURE
priv_level:
* | *.* | db_name.* | db_name.tbl_name | tbl_name | db_name.routine_name
with_option:
GRANT OPTION 可以将自己的权限授予给别人
| MAX_QUERIES_PER_HOUR count 每小时最多允许发起多少次查询请求
| MAX_UPDATES_PER_HOUR count 每小时最多允许发起多少次更新请求
| MAX_CONNECTIONS_PER_HOUR count 每小时最多允许发起多少次连接请求
| MAX_USER_CONNECTIONS count 每个用户最多允许同时连接几次

GRANT EXECUTE ON FUNCTION db.abc TO username@'%';

INSERT INTO mysql.user
mysql> FLUSH PRIVILEGES;

查看用户的授权信息：
SHOW GRANTS FOR 'username@host';

删除用户：
DROP USER 'username'@'host'

重命名用户：
RENAME USER old_name TO new_name

回收权限：
REVOKE
priv_type [(column_list)]
[, priv_type [(column_list)]] ...
ON [object_type] priv_level
FROM user [, user] ...
revoke select on chendb.* from chen@'%';

启动mysqld_safe时传递两个参数：
--skip-grant-tables 跳过授权表
--skip-networking 跳过从网络登录

通过更新 授权表方式直接修改其密码，而后移除此两个选项重启服务器。

mysql用户都是保存在mysql.user中的（user表中有user，host，password等列）通过修改mysql.user可以实现用户控制

修改root密码
#mysqladmin -u root -hHOST -p password 'new password'

创建用户
登录:  #mysql -u root -p
创建用户： #create user 'your username'@'localhost' identified by 'your password';

授权：
GRANT privileges ON databasename.tablename TO 'username'@'host'  identified by 'password';

例：

#grant all on *.* to ‘your username’@'%';     *.*表示任意databasename.tablename

为用户设置密码：
1.mysql>SET PASSWORD FOR 'username'@'host' = PASSWORD('newpassword');
FLUSH PRIVILEGES； 重读授权表
例：
mysql>set password for 'your username'@'%'=password("newpassword");
2.mysql>UPDATE user SET password=PASSWORD('newpassword') WHERE user='USERNAME' AND host='HOST';