mysql语句查询用户权限过程详解

Z时代
2024-01-10
分类：IT

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>