mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| test |
+--------------------+
mysql> use mysql
Database changed
mysql> show tables;
+---------------------------+
| Tables_in_mysql |
+---------------------------+
| columns_priv |
| db |
| event |
| func |
| general_log |
| help_category |
| help_keyword |
| help_relation |
| help_topic |
| host |
| ndb_binlog_index |
| plugin |
| proc |
| procs_priv |
| servers |
| slow_log |
| tables_priv |
| time_zone |
| time_zone_leap_second |
| time_zone_name |
| time_zone_transition |
| time_zone_transition_type |
| user |
+---------------------------+
23 rows in set (0.00 sec)
mysql> create user allen identified by 'allen' ;
Query OK, 0 rows affected (0.39 sec) <span style="font-family: 微软雅黑;"> </span>
mysql> select user,host,super_priv from user;
+------+-----------------------+------------+
| user | host | super_priv |
+------+-----------------------+------------+
| root | localhost | Y |
| root | localhost.localdomain | Y |
| root | 127.0.0.1 | Y |
| | localhost | N |
| | localhost.localdomain | N |
| allen | % | N |
+------+-----------------------+------------+
6 rows in set (0.00 sec)
mysql>
mysql> drop user allen;
Query OK, 0 rows affected (0.00 sec)
mysql> select user,host,super_priv from user;
+------+-----------------------+------------+
| user | host | super_priv |
+------+-----------------------+------------+
| root | localhost | Y |
| root | localhost.localdomain | Y |
| root | 127.0.0.1 | Y |
| | localhost | N |
| | localhost.localdomain | N |
+------+-----------------------+------------+
5 rows in set (0.00 sec)
[root@localhost ~]# mysql -u allen -p -h 172.27.35.8
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
......
mysql>
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| db_users |
| mysql |
| test |
+--------------------+
4 rows in set (0.00 sec)
mysql> usse db_users;
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'usse db_users' at line 1
发现用户allen无法使用db_users数据库,退出登陆后使用root用户给allen赋予所有权限。mysql> grant all privileges on *.* to allen@localhost;
[root@localhost ~]# mysql -u allen -p -h 172.27.35.8
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
......
mysql> use db_users;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql>
[root@localhost ~]# mysql -u allen -p -h 172.27.35.8
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
......
mysql> create user allen_test1 identified by 'allen_test';
Query OK, 0 rows affected (0.00 sec)
mysql> grant select on *.* to allen_test1@localhost;
ERROR 1045 (28000): Access denied for user 'allen'@'%' (using password: YES)
mysql>
[root@localhost ~]# mysql -u root -p
Enter password:
......
mysql> grant all privileges on *.* to allen@'%' with grant option;
Query OK, 0 rows affected (0.00 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)
mysql> quit
[root@localhost ~]# mysql -u allen -p -h 172.27.35.8
Enter password:
......
mysql> grant select on *.* to allen_test1@localhost;
Query OK, 0 rows affected (0.00 sec)
发现现在allen用户给allen_test授权成功。[root@localhost ~]# mysql -u root -p
Enter password:
......
mysql> grant all privileges on db_users.* to allen_test2@'%' identified by 'allen';
Query OK, 0 rows affected (0.01 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)
mysql> quit
Bye
然后使用allen_test2用户登录:[root@localhost ~]# mysql -u allen_test2 -p -h 192.168.65.30
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
......
mysql> use db_users;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> create table tb_test(name varchar(32), sex bool);
Query OK, 0 rows affected (0.06 sec)
mysql> insert into tb_test values ('allen', 1);
Query OK, 1 row affected (0.00 sec)
mysql> create database db_test;
ERROR 1044 (42000): Access denied for user 'allen_test2'@'%' to database 'db_test'
mysql>
可以看到,如果执行db_users数据库内操作是可以的,但创建一个新的数据库就会出错。说明数据库级权限已经生效 。3.数据表级权限范围是在给定的一个数据表中所有的目标的操作权限,这些权限会存储在mysql.tables_priv中,通常一个数据表所拥有的权限有select、insert、delete、update等。下面为一个用户创建一个只有select的权限:
[root@localhost ~]# mysql -uroot -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
mysql> grant select on db_users.* to allen_test3@'%' identified by 'allen';
Query OK, 0 rows affected (0.00 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)
mysql> quit
Bye
使用用户allen_test3用户登录:[root@localhost ~]# mysql -u allen_test3 -p -h 192.168.65.30
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
mysql> select * from tb_test;
+-------+------+
| name | sex |
+-------+------+
| allen | 1 |
+-------+------+
1 row in set (0.00 sec)
mysql> insert into tb_test values ('Lily', 0);
ERROR 1142 (42000): INSERT command denied to user 'allen_test3'@'192.168.65.30' for table 'tb_test'
mysql>
可见执行查询操作是可以的,但是执行插入操作出错。4.字段级是在字段一级对用户进行全线管理,设定用户只有若干字段的某些操作权限,字段的权限信息存储在mysql.columns_priv表中。下例对一个新用户赋予db_users数据库中tb_test表的sex字段查看和更新的权限。
[root@localhost ~]# mysql -u root -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
mysql> grant select,update(sex) on db_users.tb_test to allen_test4@'%' identified by 'allen';
Query OK, 0 rows affected (0.01 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.01 sec)
mysql> quit
Bye
allen_test4用户登录验证权限授予是否成功:[root@localhost ~]# mysql -u allen_test4 -p -h 192.168.65.26
Enter password:
......
mysql> use db_users;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> select * from tb_test;
+-------+------+
| name | sex |
+-------+------+
| allen | 1 |
+-------+------+
1 row in set (0.00 sec)
mysql> update tb_test set sex=0 where name='allen';
Query OK, 1 row affected (0.01 sec)
Rows matched: 1 Changed: 1 Warnings: 0
mysql> select * from tb_test;
+-------+------+
| name | sex |
+-------+------+
| allen | 0 |
+-------+------+
1 row in set (0.00 sec)
mysql> update tb_test set name='allen_new';
ERROR 1143 (42000): UPDATE command denied to user 'allen_test4'@'192.168.65.26' for column 'name' in table 'tb_test'
mysql>
可以看到select权限没有问题,也可以对sex字段进行更新操作。但是更新name字段报错,因为没有授予其权限。使用show grants可以查看用户已经获得的权限,查看自己的操作权限使用show grants命令可以查看自身权限,使用show grants for username可以查看用户username的权限。下例为查看root用户自身和查看allen_test4的操作权限:
[root@localhost ~]# mysql -u root -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
......
mysql> show grants;
+----------------------------------------------------------------------------------------------------------------------------------------+
| Grants for root@localhost |
+----------------------------------------------------------------------------------------------------------------------------------------+
| GRANT ALL PRIVILEGES ON *.* TO 'root'@'localhost' IDENTIFIED BY PASSWORD '*6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9' WITH GRANT OPTION |
+----------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)
mysql> show grants for allen_test4;
+------------------------------------------------------------------------------------------------------------+
| Grants for allen_test4@% |
+------------------------------------------------------------------------------------------------------------+
| GRANT USAGE ON *.* TO 'allen_test4'@'%' IDENTIFIED BY PASSWORD '*C94FD2FCBF408CBBFAAB9C07FF4221D265AFB18F' |
| GRANT SELECT, UPDATE (sex) ON `db_users`.`tb_test` TO 'allen_test4'@'%' |
+------------------------------------------------------------------------------------------------------------+
2 rows in set (0.00 sec)
和grant相反的操作时使用revoke操作,revoke作用是回收或者取消权限。1.撤销全部权限,
mysql> show grants for allen_test2;
+------------------------------------------------------------------------------------------------------------+
| Grants for allen_test2@% |
+------------------------------------------------------------------------------------------------------------+
| GRANT USAGE ON *.* TO 'allen_test2'@'%' IDENTIFIED BY PASSWORD '*C94FD2FCBF408CBBFAAB9C07FF4221D265AFB18F' |
| GRANT ALL PRIVILEGES ON `db_users`.* TO 'allen_test2'@'%' |
+------------------------------------------------------------------------------------------------------------+
2 rows in set (0.00 sec)
mysql> revoke all privileges, grant option from allen_test2;
Query OK, 0 rows affected (0.00 sec)
mysql> show grants for allen_test2;
+------------------------------------------------------------------------------------------------------------+
| Grants for allen_test2@% |
+------------------------------------------------------------------------------------------------------------+
| GRANT USAGE ON *.* TO 'allen_test2'@'%' IDENTIFIED BY PASSWORD '*C94FD2FCBF408CBBFAAB9C07FF4221D265AFB18F' |
+------------------------------------------------------------------------------------------------------------+
1 row in set (0.01 sec)
mysql>
2.撤销表级某类权限,例如用户allen_test3权限如下:
mysql> show grants for allen_test3;
+------------------------------------------------------------------------------------------------------------+
| Grants for allen_test3@% |
+------------------------------------------------------------------------------------------------------------+
| GRANT USAGE ON *.* TO 'allen_test3'@'%' IDENTIFIED BY PASSWORD '*C94FD2FCBF408CBBFAAB9C07FF4221D265AFB18F' |
| GRANT SELECT ON `db_users`.* TO 'allen_test3'@'%' |
+------------------------------------------------------------------------------------------------------------+
2 rows in set (0.00 sec)
mysql>
执行撤销后权限如下:mysql> revoke select on db_users.* from allen_test3;
Query OK, 0 rows affected (0.00 sec)
mysql> show grants for allen_test3;
+------------------------------------------------------------------------------------------------------------+
| Grants for allen_test3@% |
+------------------------------------------------------------------------------------------------------------+
| GRANT USAGE ON *.* TO 'allen_test3'@'%' IDENTIFIED BY PASSWORD '*C94FD2FCBF408CBBFAAB9C07FF4221D265AFB18F' |
+------------------------------------------------------------------------------------------------------------+
1 row in set (0.01 sec)
mysql>
3.撤销某字段权限,例如allen_test4权限如下:mysql> show grants for allen_test4;
+------------------------------------------------------------------------------------------------------------+
| Grants for allen_test4@% |
+------------------------------------------------------------------------------------------------------------+
| GRANT USAGE ON *.* TO 'allen_test4'@'%' IDENTIFIED BY PASSWORD '*C94FD2FCBF408CBBFAAB9C07FF4221D265AFB18F' |
| GRANT SELECT, UPDATE (sex) ON `db_users`.`tb_test` TO 'allen_test4'@'%' |
+------------------------------------------------------------------------------------------------------------+
2 rows in set (0.00 sec)
可见用户allen_test4拥有select和update 字段sex的权限,现在撤销update的sex字段,如下:mysql> revoke update(sex) on db_users.tb_test from allen_test4;
Query OK, 0 rows affected (0.00 sec)
mysql> show grants for allen_test4;
+------------------------------------------------------------------------------------------------------------+
| Grants for allen_test4@% |
+------------------------------------------------------------------------------------------------------------+
| GRANT USAGE ON *.* TO 'allen_test4'@'%' IDENTIFIED BY PASSWORD '*C94FD2FCBF408CBBFAAB9C07FF4221D265AFB18F' |
| GRANT SELECT ON `db_users`.`tb_test` TO 'allen_test4'@'%' |
+------------------------------------------------------------------------------------------------------------+
2 rows in set (0.00 sec)
mysql>
最后附上查看所有用户的sql语句:mysql> use mysql;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> select user from user;
+-------------+
| user |
+-------------+
| allen_test2 |
| allen_test3 |
| allen_test4 |
| root |
| |
| root |
| |
| root |
+-------------+
权限管理就到此为止了。