mysql user权限表

默认安装的mysql数据中存在数据库mysql，其中有表user，主要是进行权限控制，查询user表，内容如下:

mysql> select host,user from mysql.user;
+---------------------------------+------+
| host | user |
+---------------------------------+------+
| % | root |
| 127.0.0.1 | root |
| ::1 | root |
| cp01-rdqa-dev419.cp01 | |
| cp01-rdqa-dev419.cp01 | root |
| localhost | |
| localhost | root |
+---------------------------------+------+
7 rows in set (0.00 sec)

机器的域名为cp01-rdqa-dev419.cp01

mysql中权限的控制是通过user表进行的，其中host，user两个字段来确定一种权限，例如 root@localhost和root@cp01-rdqa-dev419.cp01代表不同的权限

默认存在一个匿名用户，user为空，查询该匿名用户的权限信息，命令如下：

mysql> show grants for ''@'localhost';
+--------------------------------------+
| Grants for @localhost |
+--------------------------------------+
| GRANT USAGE ON *.* TO ''@'localhost' |
+--------------------------------------+
1 row in set (0.00 sec)

USAGE权限是表示“无权限”，就是一个没有任何权限的用户

通过下面的命令进行授权

grant all privileges on *.* to ''@'localhost' identified by 'root' with grant option;
或者
grant all privileges on *.* to ''@'localhost';

mysql> grant all privileges on *.* to ''@'localhost';
Query OK, 0 rows affected (0.00 sec)

mysql> show grants for ''@'localhost';
+-----------------------------------------------+
| Grants for @localhost |
+-----------------------------------------------+
| GRANT ALL PRIVILEGES ON *.* TO ''@'localhost' |
+-----------------------------------------------+
1 row in set (0.00 sec)

//查询用户:root，host:localhost 的授权信息
mysql> SHOW GRANTS FOR 'root'@'localhost';
+----------------------------------------------------------------------------------------------------------------------------------------+
| Grants for root@localhost |
+----------------------------------------------------------------------------------------------------------------------------------------+
| GRANT ALL PRIVILEGES ON *.* TO 'root'@'localhost' IDENTIFIED BY PASSWORD '*81F5E21E35407D884A6CD4A731AEBFB6AF209E1B' WITH GRANT OPTION |
| GRANT PROXY ON ''@'' TO 'root'@'localhost' WITH GRANT OPTION |
+----------------------------------------------------------------------------------------------------------------------------------------+
2 rows in set (0.00 sec)

参考
http://www.cnblogs.com/fslnet/p/3143344.html
mysql 用户管理和权限设置