MYSQL用户权限管理(Grant,Revoke)

授权表使用举例
grant用于给增加用户和创建权限，revoke用于删除用户权限。

grant 语法

GRANT priv_type [(column_list)] [, priv_type [(column_list)]] ...
    ON [object_type] {tbl_name | * | *.* | db_name.*}
    TO user [IDENTIFIED BY [PASSWORD] 'password']
        [, user [IDENTIFIED BY [PASSWORD] 'password']] ...
    [REQUIRE
        NONE |
        [{SSL| X509}]
        [CIPHER 'cipher' [AND]]
        [ISSUER 'issuer' [AND]]
        [SUBJECT 'subject']]
    [WITH with_option [with_option] ...]

object_type =
    TABLE
  | FUNCTION
  | PROCEDURE

with_option =
    GRANT OPTION
  | MAX_QUERIES_PER_HOUR count
  | MAX_UPDATES_PER_HOUR count
  | MAX_CONNECTIONS_PER_HOUR count
  | MAX_USER_CONNECTIONS count

REVOKE priv_type [(column_list)] [, priv_type [(column_list)]] ...
    ON [object_type] {tbl_name | * | *.* | db_name.*}
    FROM user [, user] ...

下面是一些用grant增加用户和创建权限的例子：

mysql> grant all privileges on *.* to test@localhost identified by 'test' with grant option;

这句增加一个本地具有所有权限的test用户（超级用户），密码是test。ON子句中的*.*意味着" 所有数据库、所有表"。with grant option表示它具有grant权限。

mysql> grant select,insert,update,delete,create,drop  on test.* to test1@'192.168.1.0/255.255.255.0' identified by 'test';

这句是增加了一个 test1用户，口令是test，但是它只能从C类子网192.168.1连接，对test库有 select,insert,update,delete,create,drop操作权限。
用grant语句创建权限是不需要再手工刷新授权表的，因为它已经自动刷新了。
给用户创建权限还可以通过直接修改授权表：

mysql> insert into user values("localhost","test",password("test"),"Y","Y","Y","Y","Y","Y","Y","Y","Y","Y","Y","Y","Y","Y");
mysql> flush privileges;

这两句和上面第一句grant的效果是一样的，也是增加了一个本地的test超级用户。我们看到用grant方便多了，而且还不需flush privileges
。
mysql> insert into user (host,user,password) values("192.168.1.0/255.255.255.0","test1",PASSWORD("test"));
mysql> insert into db values("192.168.1.0/255.255.255.0","test","test1","Y","Y","Y","Y","Y","Y","N","N","N","N")
mysql> flush privileges;

这 三句和上面第二句grant的效果也是一样的，也是增加了一个只能从C类子网192.168.1连接，对test库有 select,insert,update,delete,create,drop操作权限的test1用户，口令是test。要取消一个用户的权限，使 用revoke语句。revoke的语法非常类似于grant语句，除了to用from取代并且没有identified by和with grant
option子句，下面是用revoke删除用户权限的例子：

mysql> revoke all on test.* from test1@'192.168.1.0/255.255.255.0';

这句revoke就撤消了上面第二句 grant创建的权限，但是test1用户并没有被删除，必须手工从user表删除：

mysql> delete from user where user='test1';
mysql> flush privileges;

这样，test1用户就彻底删除了。

这些只是MySQL授权表的简单使用，更多详细的资料请见MySQL提供的手册。