MySQL是一種流行的關系型數據庫管理系統，在數據管理中使用廣泛。在MySQL中，一個用戶需要授權才能訪問和操作數據庫中的數據。當需要了解哪些用戶具有哪些權限時，可以通過查詢MySQL數據庫獲取。本文將介紹如何查詢MySQL用戶權限。

查看MySQL中所有用戶：
mysql>select user,host from mysql.user;
+------------------+-----------+
| user             | host      |
+------------------+-----------+
| root             | localhost |
| mysql.session    | localhost |
| mysql.sys        | localhost |
| debian-sys-maint | localhost |
+------------------+-----------+
查看用戶的權限：
mysql>show grants for 'user'@'localhost';
+------------------------------------------------------------------------------------------------------+
| Grants for user@localhost                                                                            |
+------------------------------------------------------------------------------------------------------+
| GRANT USAGE ON *.* TO 'user'@'localhost' IDENTIFIED BY PASSWORD 'password_hash'                       |
| GRANT SELECT, INSERT, UPDATE ON `database`.`table` TO 'user'@'localhost'                              |
+------------------------------------------------------------------------------------------------------+
查詢MySQL中特定用戶權限：
mysql>SELECT Db, User, Host, Select_priv, Insert_priv, Update_priv, Delete_priv from mysql.db where User = 'user'; 
+-----------+------+-----------+-------------+--------------+--------------+-------------+
| Db        | User | Host      | Select_priv | Insert_priv  | Update_priv | Delete_priv |
+-----------+------+-----------+-------------+--------------+--------------+-------------+
| database1 | user | localhost | Y           | Y            | Y            | Y           |
| database2 | user | localhost | Y           | N            | N            | N           |
+-----------+------+-----------+-------------+--------------+--------------+-------------+

通過上述查詢方法，您可以獲取MySQL用戶的權限信息。這對于數據庫管理和安全性評估非常重要。希望本文能為您帶來幫助。