MySQL用户管理

1. MySQL用户管理

'user'@'host';
 host:IP、主机名、NETWORK、%(任意长字符),_(任意单个字符)    
skip_name_resolve={ON|OFF} 跳过主机名解析
 [root@node2 ~]# vim /etc/my.cnf
 skip_name_resolve=ON

 

2.查看用户
示例：

MariaDB [mysql]> SELECT User,Host,Password FROM user;

 

3.创建用户
CREATE USER  'user'@'host' [IDENTIFIED BY [PASSWORD] 'password'] [,'user'@'host' [IDENTIFIED BY [PASSWORD] 'password']...]
示例：

MariaDB [(none)]> CREATE USER 'tom'@'127.0.0.1' IDENTIFIED BY 'liumanlin' , 'jerry'@'%' IDENTIFIED BY 'liumanlin';

 

4.重命名：RENAME USER
RENAME USER old_user TO new_user[, old_user TO new_user] ...
示例：

MariaDB [mysql]> RENAME USER 'tom'@'127.0.0.1' TO 'jerry'@'172.18.%.%';

 

5.删除用户
DROP USER 'user'@'host' [, 'user'@'host'] ...
示例：

MariaDB [mysql]> DROP USER 'jerry'@'%';
MariaDB [mysql]> DROP USER ''@'localhost';

 

6.让MySQL重新加载授权列表
FLUSH PRIVILEGES;
示例：

MariaDB [mysql]> FLUSH PRIVILEGES;

 

7.修改用户密码
(1) SET PASSWORD [FOR 'user'@'host'] = PASSWORD('cleartext password'); PASSWORD是MySQL内建加密函数
示例：

MariaDB [mysql]> SET PASSWORD FOR 'root'@'localhost' = PASSWORD('liumanlin');
MariaDB [mysql]> FLUSH PRIVILEGES;

(2) UPDATE mysql.user SET Password=PASSWORD('cleartext password')  WHERE User='USERNAME' AND Host='HOST';
示例：

MariaDB [mysql]> UPDATE user SET Password=PASSWORD('liumanlin') WHERE User='root' AND Host='127.0.0.1';
MariaDB [mysql]> FLUSH PRIVILEGES;

(3) mysqladmin -uUSERNAME -hHOST -p  password 'NEW_PASS'
示例：

[root@node2 ~]# mysqladmin -h127.0.0.1 -uroot -p password 'liumanlin';

 

8.忘记管理员密码的解决办法
(1) 启动mysqld进程时，使用--skip-grant-tables和--skip-networking选项
示例：
CentOS 7：

[root@node2 ~]# vim /usr/lib/systemd/system/mariadb.service
 ExecStart=/usr/bin/mysqld_safe --basedir=/usr --skip-grant-tables --skip-networking
[root@node2 ~]# systemctl daemon-reload
[root@node2 ~]# systemctl restart mariadb.service

CentOS 6：

[root@node2 ~]# vim /etc/init.d/mysqld 同理

(2) 通过UPDATE命令修改管理员密码
示例：

MariaDB [mysql]> UPDATE user SET Password=PASSWORD('liumanlin') WHERE User='root' AND Host='127.0.0.1';
[root@node2 ~]# vim /usr/lib/systemd/system/mariadb.service
ExecStart=/usr/bin/mysqld_safe --basedir=/usr

(3) 以正常方式启动mysqld进程；
示例：

[root@node2 ~]# systemctl daemon-reload
[root@node2 ~]# systemctl restart mariadb.service

 

9.授权：GRANT

GRANT priv_type [(column_list)] [, priv_type [(column_list)]] ...
ON [object_type] priv_level 
TO user_specification [, user_specification] ...
[REQUIRE {NONE | ssl_option [[AND] ssl_option] ...}]
[WITH with_option ...]

object_type(对象类型):
 TABLE
 | FUNCTION
 | PROCEDURE
priv_level:
 *
 | *.*(所有库的所有表)
 | db_name.*(指定库的所有表)
 | db_name.tbl_name(指定库的指定表)
 | tbl_name(指定表)
 | db_name.routine_name(指定库的指定函数)
ssl_option:
 SSL
 | X509
 | CIPHER 'cipher'
 | ISSUER 'issuer'
 | SUBJECT 'subject'    
with_option:
 GRANT OPTION
 | MAX_QUERIES_PER_HOUR count
 | MAX_UPDATES_PER_HOUR count
 | MAX_CONNECTIONS_PER_HOUR count
 | MAX_USER_CONNECTIONS count
示例1：

MariaDB [mysql]> GRANT CREATE ON hidb.* TO 'jerry'@'172.18.%.%';
[root@node2 ~]# mysql -ujerry -h172.18.67.12 -p
MariaDB [(none)]> CREATE DATABASE hidb;
MariaDB [(none)]> use hidb;
MariaDB [hidb]> CREATE TABLE tbl1 (name CHAR(20));
MariaDB [hidb]> CREATE INDEX test ON tbl1(name);
ERROR 1142 (42000): INDEX command denied to user 'jerry'@'172.18.67.12' for table 'tbl1' (无权创建索引，用以下方法)
MariaDB [mysql]> GRANT INDEX ON hidb.* TO 'jerry'@'172.18.%.%';
MariaDB [mysql]> SHOW GRANTS  FOR 'jerry'@'172.18.%.%';
MariaDB [hidb]> CREATE INDEX test ON tbl1(name); (授权成功)

示例2：

MariaDB [mysql]> CREATE USER 'tom'@'172.18.%.%' IDENTIFIED BY 'liumanlin';
[root@node2 ~]# mysql -utom -h172.18.67.12 -p (可正常登录)
MariaDB [mysql]> GRANT ALL ON hidb.* TO 'tom'@'172.18.%.%' REQUIRE SSL; (使用ssl授权登录)
MariaDB [mysql]> SHOW GRANTS FOR 'tom'@'172.18.%.%';
MariaDB [mysql]> FLUSH PRIVILEGES;
[root@node2 ~]# mysql -utom -h172.18.67.12 -p
Enter password: 
ERROR 1045 (28000): Access denied for user 'tom'@'172.18.67.12' (using password: YES) (无法连接，需指明ssl证书)

示例3：

MariaDB [mysql]> SHOW GLOBAL VARIABLES LIKE '%ssl%';
+---------------+----------+
| Variable_name | Value    |
+---------------+----------+
| have_openssl  | DISABLED |
| have_ssl      | DISABLED |
| ssl_ca        |          |
| ssl_capath    |          |
| ssl_cert      |          |
| ssl_cipher    |          |
| ssl_key       |          |
+---------------+----------+

 

10.查看授权：SHOW GRANTS
SHOW GRANTS [FOR 'user'@'host']
示例：

MariaDB [mysql]> SHOW GRANTS FOR 'tom'@'172.18.%.%';

 

11.取消授权：REVOKE

REVOKE  priv_type [(column_list)][, priv_type [(column_list)]] ...
ON [object_type] priv_level
FROM  'user'@'host' [,  'user'@'host'] ...
REVOKE ALL PRIVILEGES, GRANT OPTION
FROM user [, user] ...

示例：

MariaDB [mysql]> REVOKE CREATE VIEW ON hidb.* FROM 'tom'@'172.18.%.%';
MariaDB [mysql]> SHOW GRANTS FOR 'tom'@'172.18.%.%';
MariaDB [mysql]> FLUSH PRIVILEGES;