MySQL授权问题总结
我用localhost的root帐号不能连 最后请教DBA组新建用户搞定!
现弄些受权用户的资料 以备不时之需
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。
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 privileges 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。

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