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。
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