如何知道可以访问数据库（MySQL）的所有用户？

Question

如何知道所有可以访问数据库的用户？

Answer 1

以管理员用户身份（通常以 root 用户身份）连接到 mysql 实例并给出以下命令...

select user from mysql.db where db='DB_NAME';

Answer 2

user79644 的回答获取具有数据库级权限的用户，但会错过只有表级、列级或过程级权限的用户。要找到所有这些，请使用以下语句：

SELECT user,host FROM db WHERE db='name';
SELECT user,host FROM tables_priv WHERE db='name';
SELECT user,host FROM columns_priv WHERE db='name';
SELECT user,host FROM procs_priv WHERE db='name';

至少在 MySQL 5.5 中，似乎拥有列级权限意味着您拥有表级权限。拥有表级权限并不意味着您拥有数据库级权限。不确定过程级权限。

Answer 3

# current users that access the db
mysql> show processlist;
+-----+------+-----------+------+---------+------+-------+------------------+
| Id  | User | Host      | db   | Command | Time | State | Info             |
+-----+------+-----------+------+---------+------+-------+------------------+
| 214 | root | localhost | NULL | Query   |    0 | NULL  | show processlist |
+-----+------+-----------+------+---------+------+-------+------------------+

# who can access what at anytime and his privilege level
mysql> show grants;
+---------------------------------------------------------------------+
| Grants for root@localhost                                           |
+---------------------------------------------------------------------+
| GRANT ALL PRIVILEGES ON *.* TO 'root'@'localhost' WITH GRANT OPTION |
+---------------------------------------------------------------------+

# what privileges are available
mysql> show privileges;