在MySQL中，如何查看一個用戶被授予了那些權限呢？ 授予用戶的權限可能分全局層級權限、數據庫層級權限、表層級別權限、列層級別權限、子程序層級權限。具體分類如下：
全局層級
全局權限適用于一個給定服務器中的所有數據庫。這些權限存儲在mysql.user表中。GRANT ALL ON *.*和REVOKE ALL ON *.*只授予和撤銷全局權限。
數據庫層級
數據庫權限適用于一個給定數據庫中的所有目標。這些權限存儲在mysql.db和mysql.host表中。GRANT ALL ON db_name.*和REVOKE ALL ON db_name.*只授予和撤銷數據庫權限。
表層級
表權限適用于一個給定表中的所有列。這些權限存儲在mysql.tables_priv表中。GRANT ALL ON db_name.tbl_name和REVOKE ALL ON db_name.tbl_name只授予和撤銷表權限。
列層級
列權限適用于一個給定表中的單一列。這些權限存儲在mysql.columns_priv表中。當使用REVOKE時，您必須指定與被授權列相同的列。
子程序層級
CREATE ROUTINE, ALTER ROUTINE, EXECUTE和GRANT權限適用于已存儲的子程序。這些權限可以被授予為全局層級和數據庫層級。而且，除了CREATE ROUTINE外，這些權限可以被授予為子程序層級，并存儲在mysql.procs_priv表中。
1：那么我們來創建一個測試賬號test，授予全局層級的權限。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>
那么可以用下面兩種方式查詢授予test的權限。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：那么我們來創建一個測試賬號test，授予數據庫層級的權限。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; --可以看到無任何授權。
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：那么我們來創建一個測試賬號test，授予表層級的權限。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：那么我們來創建一個測試賬號test，授予列層級的權限。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：那么我們來創建一個測試賬號test，授子程序層級的權限。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，如果需要查看用戶被授予的權限，就需要從這五個層級來查看被授予的權限。從上到下或從小到上，逐一檢查各個層級被授予的權限。
以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支持腳本之家。
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