一、准备环境：

系统版本：

    CentOS Linux release 7.6.1810

数据库包名和数据库版本：

    mysql-community-client-8.0.31-1.el7.x86_64.rpm
    mysql-community-common-8.0.31-1.el7.x86_64.rpm
    mysql-community-libs-8.0.31-1.el7.x86_64.rpm
    mysql-community-server-8.0.31-1.el7.x86_64.rpm

官方下载地址：

    https://downloads.mysql.com/archives/community/

关闭 firewalld&selinux

    sed -i 's/^SELINUX=enforcing/SELINUX=disabled/g' /etc/selinux/config
    #需重启服务器服务器生效
    systemctl stop firewalld && systemctl disable firewalld    

卸载已有mysql&mriadb

    rpm -qa | grep mriadb
    rpm -qa | grep mysql
    rpm -e mriadb****** --nodeps
    rpm -e mysql******* --nodeps

删除系统附带的MySQL文件

    find / -name *mysql* | xargs rm -rf

二、安装MySQL

1、安装MySQL RPM包

    rpm -ivh mysql-community* --nodeps

2、启动mysql服务

    systemctl start mysqld

3、查看临时密码

    [root@localhost ~]# cat /var/log/mysqld.log | grep password
    2023-02-15T08:52:45.705996Z 6 [Note] [MY-010454] [Server] A temporary password is generated for root@localhost: 54E(KmazNZ0u    #临时密码为54E(KmazNZ0u

4、登录MySQL并修改临时密码

  [root@localhost ~]# mysql -uroot -p
  Enter password:    #使用#3得到的临时密码登录
  修改密码：
  mysql> alter user 'root'@'localhost' identified by 'xxxxxxx'; 

5、创建远程访问用户和密码、并赋予权限

   创建用户并指定密码；
       create user 'root'@'%' identified with mysql_native_password by 'xxxxxx';　　
   授权；
       grant all privileges on *.* to 'root'@'%' with grant option;　
   刷新权限；
       flush privileges;