MySQL 查看用户授予的权限

 

在MySQL中，如何查看一个用户被授予了那些权限呢？ 授予用户的权限可能分全局层级权限、数据库层级权限、表层级别权限、列层级别权限、子程序层级权限。具体分类如下：

全局层级

全局权限适用于一个给定服务器中的所有数据库。这些权限存储在mysql.user表中。GRANT ALL ON *.*和REVOKE ALL ON *.*只授予和撤销全局权限。

 

数据库层级

数据库权限适用于一个给定数据库中的所有目标。这些权限存储在mysql.db和mysql.host表中。GRANT ALL ON db_name.*和REVOKE ALL ON db_name.*只授予和撤销数据库权限。

表层级

 

表权限适用于一个给定表中的所有列。这些权限存储在mysql.tables_priv表中。GRANT ALL ON db_name.tbl_name和REVOKE ALL ON db_name.tbl_name只授予和撤销表权限。

列层级

 

列权限适用于一个给定表中的单一列。这些权限存储在mysql.columns_priv表中。当使用REVOKE时，您必须指定与被授权列相同的列。

子程序层级

CREATE ROUTINE, ALTER ROUTINE, EXECUTE和GRANT权限适用于已存储的子程序。这些权限可以被授予为全局层级和数据库层级。而且，除了CREATE ROUTINE外，这些权限可以被授予为子程序层级，并存储在mysql.procs_priv表中。

1：那么我们来创建一个测试账号test，授予全局层级的权限。如下所示：

mysql> grant select,insert on *.* to test@'%' identified by 'test';

Query OK, 0 rows affected (0.01 sec)

mysql> flush privileges;

Query OK, 0 rows affected (0.00 sec)

mysql> 

那么可以用下面两种方式查询授予test的权限。如下所示：

mysql> show grants for test;

+--------------------------------------------------------------------------------------------------------------+

| Grants for test@%                                                                                            |

+--------------------------------------------------------------------------------------------------------------+

| GRANT SELECT, INSERT ON *.* TO 'test'@'%' IDENTIFIED BY PASSWORD '*94BDCEBE19083CE2A1F959FD02F964C7AF4CFC29' |

+--------------------------------------------------------------------------------------------------------------+

1 row in set (0.00 sec)

mysql> select * from mysql.user where user='test'\G;

*************************** 1. row ***************************

                  Host: %

                  User: test

              Password: *94BDCEBE19083CE2A1F959FD02F964C7AF4CFC29

           Select_priv: Y

           Insert_priv: Y

           Update_priv: N

           Delete_priv: N

           Create_priv: N

             Drop_priv: N

           Reload_priv: N

         Shutdown_priv: N

          Process_priv: N

             File_priv: N

            Grant_priv: N

       References_priv: N

            Index_priv: N

            Alter_priv: N

          Show_db_priv: N

            Super_priv: N

 Create_tmp_table_priv: N

      Lock_tables_priv: N

          Execute_priv: N

       Repl_slave_priv: N

      Repl_client_priv: N

      Create_view_priv: N

        Show_view_priv: N

   Create_routine_priv: N

    Alter_routine_priv: N

      Create_user_priv: N

            Event_priv: N

          Trigger_priv: N

Create_tablespace_priv: N

              ssl_type: 

            ssl_cipher: 

           x509_issuer: 

          x509_subject: 

         max_questions: 0

           max_updates: 0

       max_connections: 0

  max_user_connections: 0

                plugin: mysql_native_password

 authentication_string: 

      password_expired: N

1 row in set (0.04 sec)

ERROR: 

No query specified

mysql> 

2：那么我们来创建一个测试账号test，授予数据库层级的权限。如下所示：

mysql> drop user test;

Query OK, 0 rows affected (0.00 sec)

mysql> grant select,insert,update,delete on MyDB.* to test@'%' identified by 'test';

Query OK, 0 rows affected (0.01 sec)

mysql> 

mysql> select * from mysql.user where user='test'\G; --可以看到无任何授权。

mysql> select * from mysql.db where user='test'\G;

*************************** 1. row ***************************

                 Host: %

                   Db: MyDB

                 User: test

          Select_priv: Y

          Insert_priv: Y

          Update_priv: Y

          Delete_priv: Y

          Create_priv: N

            Drop_priv: N

           Grant_priv: N

      References_priv: N

           Index_priv: N

           Alter_priv: N

Create_tmp_table_priv: N

     Lock_tables_priv: N

     Create_view_priv: N

       Show_view_priv: N

  Create_routine_priv: N

   Alter_routine_priv: N

         Execute_priv: N

           Event_priv: N

         Trigger_priv: N

1 row in set (0.04 sec)

ERROR: 

No query specified

mysql> 

mysql> show grants for test;

+-----------------------------------------------------------------------------------------------------+

| Grants for test@%                                                                                   |

+-----------------------------------------------------------------------------------------------------+

| GRANT USAGE ON *.* TO 'test'@'%' IDENTIFIED BY PASSWORD '*94BDCEBE19083CE2A1F959FD02F964C7AF4CFC29' |

| GRANT SELECT, INSERT, UPDATE, DELETE ON `MyDB`.* TO 'test'@'%'                                      |

+-----------------------------------------------------------------------------------------------------+

2 rows in set (0.00 sec)

mysql> 

3：那么我们来创建一个测试账号test，授予表层级的权限。如下所示：

mysql> drop user test;

Query OK, 0 rows affected (0.00 sec)

mysql> flush privileges;

Query OK, 0 rows affected (0.00 sec)

mysql> grant all on MyDB.kkk to test@'%' identified by 'test';

Query OK, 0 rows affected (0.01 sec)

mysql> 

mysql> show grants for test;

+-----------------------------------------------------------------------------------------------------+

| Grants for test@%                                                                                   |

+-----------------------------------------------------------------------------------------------------+

| GRANT USAGE ON *.* TO 'test'@'%' IDENTIFIED BY PASSWORD '*94BDCEBE19083CE2A1F959FD02F964C7AF4CFC29' |

| GRANT ALL PRIVILEGES ON `MyDB`.`kkk` TO 'test'@'%'                                                  |

+-----------------------------------------------------------------------------------------------------+

2 rows in set (0.00 sec)

mysql> select * from mysql.tables_priv\G;

*************************** 1. row ***************************

       Host: %

         Db: MyDB

       User: test

 Table_name: kkk

    Grantor: root@localhost

  Timestamp: 0000-00-00 00:00:00

 Table_priv: Select,Insert,Update,Delete,Create,Drop,References,Index,Alter,Create View,Show view,Trigger

Column_priv: 

1 row in set (0.01 sec)

ERROR: 

No query specified

mysql> 

4：那么我们来创建一个测试账号test，授予列层级的权限。如下所示：

mysql> drop user test;

Query OK, 0 rows affected (0.00 sec)

mysql> flush privileges;

Query OK, 0 rows affected (0.00 sec)

mysql> grant select (id, col1) on MyDB.TEST1 to test@'%' identified by 'test';

Query OK, 0 rows affected (0.01 sec)

mysql> flush privileges;

Query OK, 0 rows affected (0.00 sec)

mysql> 

mysql> select * from mysql.columns_priv;

+------+------+------+------------+-------------+---------------------+-------------+

| Host | Db   | User | Table_name | Column_name | Timestamp           | Column_priv |

+------+------+------+------------+-------------+---------------------+-------------+

| %    | MyDB | test | TEST1      | id          | 0000-00-00 00:00:00 | Select      |

| %    | MyDB | test | TEST1      | col1        | 0000-00-00 00:00:00 | Select      |

+------+------+------+------------+-------------+---------------------+-------------+

2 rows in set (0.00 sec)

mysql> show grants for test;

+-----------------------------------------------------------------------------------------------------+

| Grants for test@%                                                                                   |

+-----------------------------------------------------------------------------------------------------+

| GRANT USAGE ON *.* TO 'test'@'%' IDENTIFIED BY PASSWORD '*94BDCEBE19083CE2A1F959FD02F964C7AF4CFC29' |

| GRANT SELECT (id, col1) ON `MyDB`.`TEST1` TO 'test'@'%'                                             |

+-----------------------------------------------------------------------------------------------------+

2 rows in set (0.00 sec)

mysql> 

5：那么我们来创建一个测试账号test，授子程序层级的权限。如下所示：

mysql> DROP PROCEDURE IF EXISTS PRC_TEST;

Query OK, 0 rows affected (0.00 sec)

mysql> DELIMITER //

mysql> CREATE PROCEDURE PRC_TEST()

    -> BEGIN

    ->    SELECT * FROM kkk;

    -> END //

Query OK, 0 rows affected (0.00 sec)

mysql> DELIMITER ;

mysql> grant execute on procedure MyDB.PRC_TEST to test@'%' identified by 'test';

Query OK, 0 rows affected (0.01 sec)

mysql> flush privileges;

Query OK, 0 rows affected (0.00 sec)

mysql> 

mysql> show grants for test;

+-----------------------------------------------------------------------------------------------------+

| Grants for test@%                                                                                   |

+-----------------------------------------------------------------------------------------------------+

| GRANT USAGE ON *.* TO 'test'@'%' IDENTIFIED BY PASSWORD '*94BDCEBE19083CE2A1F959FD02F964C7AF4CFC29' |

| GRANT EXECUTE ON PROCEDURE `MyDB`.`prc_test` TO 'test'@'%'                                          |

+-----------------------------------------------------------------------------------------------------+

2 rows in set (0.00 sec)

mysql> select * from mysql.procs_priv where User='test';

+------+------+------+--------------+--------------+----------------+-----------+---------------------+

| Host | Db   | User | Routine_name | Routine_type | Grantor        | Proc_priv | Timestamp           |

+------+------+------+--------------+--------------+----------------+-----------+---------------------+

| %    | MyDB | test | PRC_TEST     | PROCEDURE    | root@localhost | Execute   | 0000-00-00 00:00:00 |

+------+------+------+--------------+--------------+----------------+-----------+---------------------+

1 row in set (0.00 sec)

mysql> 

所以，如果需要查看用户被授予的权限，就需要从这五个层级来查看被授予的权限。从上到下或从小到上，逐一检查各个层级被授予的权限。