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mysql的问题2 我果然对于linux下的开发还很菜啊,继续记录学习mysql中出现的问题。 由于昨天根据网上教程把mysql的root(localhost)密码改了不能登陆了,又根据网上的教程把User=‘’的用户也删掉了,最后当我开始明白mysql关于用户和权限的一些东西的时候,

mysql的问题2

        我果然对于linux下的开发还很菜啊,继续记录学习mysql中出现的问题。

        由于昨天根据网上教程把mysql的root(localhost)密码改了不能登陆了,又根据网上的教程把User=‘’的用户也删掉了,最后当我开始明白mysql关于用户和权限的一些东西的时候,我mysqld_safe --user=mysql --skip-grant-tables --skip-networking &之后进入mysql查看系统的用户,发现已经没有主机名为localhost的用户了。。。

        虽然其他主机名的root用户密码已经都被设置成了“*23AE809DDACAF96AF0FD78ED04B6A265E05AA257”就是加密了的“123”,但是我尝试使用这些用户身份登录发现也没有真正的root权限。自己插入一条主机名为localhost的root用户,发现权限也有问题。。。

        干脆删掉mysql再重装好了。复习一下删除过程:

        删除软件包:rpm -e mysql-server                           //这个命令是有顺序的,一定要先删不依赖于别的软件包的软件包

        删除软件包:rpm -e mysql*******                           //不然系统会提示无法删除,我印象中依次删了4个软件包

        删除软件包:rpm -e l********

        删除软件包:rpm -e mysql*******

        妹子家里网速很好,于是直接 yum install mysql 下载速度600kb~~~~

        噢,还有yum install mysql-devel 和 yum install mysql-server  几十秒全都装好了

        启动mysql:service mysqld start……啊嘞,出现了:Redirecting to /bin/systemctl  start mysqld.service
Job failed. See system journal and 'systemctl status' for details.  好吧去看看日志:/var/log/mysqld.log 日志说:mysqld_safe A mysqld process already exists。。。。

        我真是不懂这是什么东东,只好ps -A|grep mysql  然后再 kill -9 进程号。

        再mysql -u root,嗯,终于又登陆到mysql了,不过还得设置个密码呢。


       刚刚发现之前学习的网上的update user set password = '123456' where user ="root" //这样写是错的,密码其实不是123456
       应该为update user set password = password ('123456') where user = "root";

       restart一下mysql服务,用 root 和密码 123 登陆成功,   再:

   GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' IDENTIFIED BY 'root' WITH GRANT OPTION;

   来赋予所有用户远程连接权限,终于成功了(*^__^*) 

       

  

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