角色 ( Role ) 可以用来批量管理用户，同一个角色下的用户，拥有相同的权限。那 MySQL 数据库是否也有这样的功能呢 ?答案是肯定的。MySQL 5.7.X 可以通过 mysql.proxies_priv 来模拟角色 (Role) 的功能。下面让我们来实验一下(测试的版本 MySQL 5.7.28)：
1 配置 proxy
mysql> show variables like "%proxy%"; #查看当前proxy是否开启，OFF 表示没有开启
+-----------------------------------+-------+
| Variable_name | Value |
+-----------------------------------+-------+
| check_proxy_users | OFF |
| mysql_native_password_proxy_users | OFF |
| proxy_user | |
| sha256_password_proxy_users | OFF |
+-----------------------------------+-------+
4 rows in set (0.02 sec)
mysql> set global check_proxy_users =on;
Query OK, 0 rows affected (0.00 sec)
mysql> set global mysql_native_password_proxy_users = on;
Query OK, 0 rows affected (0.01 sec)
mysql> exit
以上设置参数，对当前会话无效，需要退出后重新登录，或直接设置到 my.cnf 中去;
2 创建角色和用户
mysql> create user role_dba;
Query OK, 0 rows affected (1.03 sec)
mysql> create user 'jack';
Query OK, 0 rows affected (0.01 sec)
mysql> create user 'mary';
Query OK, 0 rows affected (0.01 sec)
用户为设置密码，如需密码可以使用 identified by '####' 设置;
3 权限映射
将 role_dba 的权限映射( map )到 jack 、mary
mysql> grant proxy on role_dba to jack;
Query OK, 0 rows affected (0.02 sec)
mysql> grant proxy on role_dba to mary;
Query OK, 0 rows affected (0.01 sec)
4 给用户赋权
给 role_dba 赋权(模拟 role 赋权)
mysql> grant select on *.* to role_dba;
Query OK, 0 rows affected (0.01 sec)
mysql> show grants for role_dba;
+---------------------------------------+
| Grants for role_dba@% |
+---------------------------------------+
| GRANT SELECT ON *.* TO 'role_dba'@'%' |
+---------------------------------------+
1 row in set (0.00 sec)
mysql> show grants for jack;
+---------------------------------------------+
| Grants for jack@% |
+---------------------------------------------+
| GRANT USAGE ON *.* TO 'jack'@'%' |
| GRANT PROXY ON 'role_dba'@'%' TO 'jack'@'%' |
+---------------------------------------------+
2 rows in set (0.00 sec)
mysql> show grants for mary;
+---------------------------------------------+
| Grants for mary@% |
+---------------------------------------------+
| GRANT USAGE ON *.* TO 'mary'@'%' |
| GRANT PROXY ON 'role_dba'@'%' TO 'mary'@'%' |
+---------------------------------------------+
2 rows in set (0.00 sec)
5 查看 mysql.proxies_priv
mysql> select * from mysql.proxies_priv;
+-----------+------+--------------+--------------+------------+----------------------+---------------------+
| Host | User | Proxied_host | Proxied_user | With_grant | Grantor | Timestamp |
+-----------+------+--------------+--------------+------------+----------------------+---------------------+
| localhost | root | | | 1 | boot@connecting host | 0000-00-00 00:00:00 |
| % | will | % | will_dba | 0 | root@localhost | 0000-00-00 00:00:00 |
| % | tom | % | will_dba | 0 | root@localhost | 0000-00-00 00:00:00 |
| % | jack | % | role_dba | 0 | root@localhost | 0000-00-00 00:00:00 |
| % | mary | % | role_dba | 0 | root@localhost | 0000-00-00 00:00:00 |
+-----------+------+--------------+--------------+------------+----------------------+---------------------+
5 rows in set (0.01 sec)
6 验证
$ mysql -h 127.0.0.1 -u jack
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 249
Server version: 5.7.28-log MySQL Community Server (GPL)
Copyright (c) 2000, 2019, Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql> select * from test.ssd limit 1;
+---+------+------+
| a | b | c |
+---+------+------+
| 1 | NULL | NULL |
+---+------+------+
1 row in set (0.01 sec)
mysql.proxies_priv 仅仅是对 Role 的模拟，和 Oracle 的角色还是有所不同的;官方称呼为 Role like。
MySQL 8.0 正式增加了 role 功能，有兴趣的同学可以自行了解。MySQL 5.6.X 模拟 Role 功能需要安装插件，具体方法可参考：https://dev.mysql.com/doc/refman/5.6/en/proxy-users.htmlhttps://dev.mysql.com/doc/refman/5.6/en/pluggable-authentication.html
原文地址：https://mp.weixin.qq.com/s/LMHJ2yMM1m31Zsy_eZmf0w
