前两天在windows的command命令行下，用mysqladmin导入过一些站上数据
结果悲催了，mysql.user的内容被改了，root上不了了，权限也变了。
结合了网络上的集中方法，终于成了。
步骤如下：
一、先把mysql停了，
win:net stop mysql
linux:service mysqld stop
以下以windows 为例
二、用mysqld hold住mysql
#mysqld --skip-grant-tables 执行后cmd窗口会Hold住，别关闭，新开一个cmd窗口
三、进入mysql
在新开的cmd窗口里，输入
#mysql -hlocalhost -uroot
没有输入密码就进入了哦，亲
四、两种操作：
A、更改密码：
UPDATE user SET Password=PASSWORD('xxx') WHERE user='root';
B、如果更改密码了还不行，那估计和我一样，权限都被导入的库冲掉了。
还需要授权，以下sql适用于mysql5.5
update user set Select_priv = "Y",Insert_priv = "Y",Update_priv = "Y",Delete_priv = "Y",Create_priv = "Y",Drop_priv = "Y",Reload_priv = "Y",Shutdown_priv = "Y",Process_priv = "Y",File_priv = "Y",Grant_priv = "Y",References_priv = "Y",Index_priv = "Y",Alter_priv = "Y",Show_db_priv = "Y",Super_priv = "Y",Create_tmp_table_priv = "Y",Lock_tables_priv = "Y",Execute_priv = "Y",Repl_slave_priv = "Y",Repl_client_priv = "Y",Create_view_priv = "Y",Show_view_priv = "Y",Create_routine_priv = "Y",Alter_routine_priv = "Y",Create_user_priv = "Y" where user="root";
五、最后别忘了刷新权限
flush privileges;
OK了，关闭一切命令行，启动mysql服务，用mysql管理工具登录看看吧。