MySQL的 安装、配置、卸载

Mysql的安装配置(基于Centos7)

安装mysql数据库

[root@master ~]# wget https://dev.mysql.com/get/mysql57-community-release-el7-9.noarch.rpm
[root@master ~]# yum -y install mysql57-community-release-el7-9.noarch.rpm
[root@master ~]# cd /etc/yum.repos.d/
[root@master ~]# yum -y install mysql-server

启动数据库

[root@master ~]# systemctil start mysqld

查询初始化数据库密码

[root@master ~]# grep 'passowrd' /var/log/mysql.log

--显示的 root@localhost: ***就是初始化的数据库登录密码

登录到数据库

[root@master ~]# mysql -uroot -p
[root@master ~]# password:

设置密码

mysql> set password for 用户名@localhost = password('新密码');

查看密码设置

mysql> show variables like 'validate_password%';

修改密码等级为低

mysql> set global validate_password_policy=LOW;

改密码长度最小为6位

mysql> set global validate_password_length=6;

设置数据库新密码

mysql> set password for 'root'@'localhost' = password('bigdata');

开启远程访问数据库

mysql> grant all privileges on *.* to 'root'@'%' identified by 'bigdata' with grant option;

mysql> flush privileges;

Mysql的完全卸载(基于Centos7)

查询与mysql有关的rpm包

[root@master ~]# rpm -qa |grep -i mysql
mysql57-community-release-el7-9.noarch
mysql-community-client-5.7.32-1.el7.x86_64
mysql-community-libs-5.7.32-1.el7.x86_64
mysql-community-libs-compat-5.7.32-1.el7.x86_64
mysql-community-common-5.7.32-1.el7.x86_64
mysql-community-server-5.7.32-1.el7.x86_64

使用yum remove命令卸载这些包

[root@master ~]# yum remove mysql57-community-release-el7-9.noarch
[root@master ~]# yum remove mysql-community-client-5.7.32-1.el7.x86_64
[root@master ~]# yum remove mysql-community-libs-5.7.32-1.el7.x86_64
[root@master ~]# yum remove mysql-community-libs-compat-5.7.32-1.el7.x86_64
[root@master ~]# yum remove mysql-community-common-5.7.32-1.el7.x86_64
[root@master ~]# yum remove mysql-community-server-5.7.32-1.el7.x86_64

查找mysql的相关目录残留并删除

[root@master ~]# find / -name mysql
/etc/selinux/targeted/active/modules/100/mysql
/var/lib/mysql
/var/lib/mysql/mysql
/usr/share/mysql

删除残留

[root@master ~]# rm -rf /etc/selinux/targeted/active/modules/100/mysql
[root@master ~]# rm -rf /var/lib/mysql
[root@master ~]# rm -rf /var/lib/mysql/mysql
[root@master ~]# rm -rf /usr/share/mysql

删除/var/log/mysqld.log

[root@master ~]# rm -rf /var/log/mysqld.log
--如果不删除这个文件，会导致新安装的mysql无法生存新密码，造成无法登陆mysql

Done~