centos7.6安装mysql5.7.xx

 # 检查

    
 rpm -qa | grep mysql
    
  
    
 # 如果有，则删除
    
 rpm -e --nodeps xxx已安装的程序
    
  
    
 # 检查并卸载
    
 yum list installed | grep mariadb
    
  
    
 # 卸载
    
 yum -y remove mariadb-libs.x86_64

 # wget方式下载

    
 wget https://dev.mysql.com/get/mysql57-community-release-el7-9.noarch.rpm
    
  
    
 mysql安装包官网：https://dev.mysql.com/downloads/mysql/
    
  
    
 # 准备的安装包
    
 mysql57-community-release-el7-9.noarch.rpm
    
 mysql-community-common-5.7.18-1.el7.x86_64.rpm
    
 mysql-community-libs-5.7.18-1.el7.x86_64.rpm 
    
 mysql-community-client-5.7.18-1.el7.x86_64.rpm  
    
 mysql-community-server-5.7.18-1.el7.x86_64.rpm
    
 mysql-community-devel-5.7.18-1.el7.x86_64.rpm
    
  
    
 # 按顺序依次安装以上准备的rpm安装包
    
 rpm -ivh mysql57-community-release-el7-9.noarch.rpm
    
 rpm -ivh mysql-community-common-5.7.18-1.el7.x86_64.rpm
    
 rpm -ivh mysql-community-libs-5.7.18-1.el7.x86_64.rpm 
    
 rpm -ivh mysql-community-client-5.7.18-1.el7.x86_64.rpm 
    
 rpm -ivh mysql-community-server-5.7.18-1.el7.x86_64.rpm
    
 rpm -ivh mysql-community-devel-5.7.18-1.el7.x86_64.rpm

 # 安装完毕启动mysql服务

    
 systemctl status mysqld.service
    
 systemctl start mysqld.service
    
  
    
 # 查看初始密码
    
 grep "password" /var/log/mysqld.log
    
 输出：
    
 A temporary password is generated for root@localhost: gbHCws;J+2k,
    
  
    
 # 登录mysql
    
 mysql -uroot -p
    
 gbHCws;J+2k,
    
  
    
 # 重新设置root密码
    
 alter user 'root'@'localhost' identified by 'Dd@2020'
    
  
    
  
    
 # 设置MYSQL允许远程用户登录
    
 show databases;
    
 use mysql;
    
 show tables;
    
 select host,user from user;
    
  
    
 执行设置远程登录信息命令
    
 grant all privileges on *.* to 'root'@'%' identified by '123456' with grant option;
    
  
    
 # 删除用户信息，只保留 host='%'
    
 delete from user where host='localhost';
    
 delete from user where host='127.0.0.1';
    
 delete from user where host='主机名';
    
  
    
 # 刷新信息
    
 flush privileges;
    
  
    
 # 退出mysql并重启mysql服务
    
 service mysqld restart;