1.官网下载mysql-8.0.15-1.el7.x86_64.rpm-bundle.tar，解压到 /usr/local/mysql/ 目录下；
2.依次安装mysql组件：
# rpm -ivh mysql-community-common-8.0.15-1.el7.x86_64.rpm
# rpm -ivh mysql-community-libs-8.0.15-1.el7.x86_64.rpm
# rpm -ivh mysql-community-libs-compat-8.0.15-1.el7.x86_64.rpm
# rpm -ivh mysql-community-client-8.0.15-1.el7.x86_64.rpm
# rpm -ivh mysql-community-server-8.0.15-1.el7.x86_64.rpm
如果有报错如：
依赖检测失败：
mysql-community-common(x86-64) >= 5.7.9 被 mysql-community-libs-5.7.19-1.el7.x86_64 需要
mariadb-libs 被 mysql-community-libs-5.7.19-1.el7.x86_64 取代
则表示该依赖已存在，则删除以前依赖，重新安装，删除命令为：
# rpm -e mysql-libs
3.启动服务：
# systemctl start mysqld.service
查看状态：
# systemctl status mysqld.service
4.修改密码：
5.7版本以后，安装mysql后默认生成密码，密码在/var/log/mysqld.log文件中，
命令搜索：#grep 'temporary password' mysqld.log
然后登陆：#mysql -uroot -p
输入密码后，进入mysql，修改密码：
mysql> use mysql;
mysql> alter user 'root'@'%' identified by 'password_123';
mysql> exit;
4.navicat连接测试：
正确输入连接信息后，可能会出现一下问题：
（1）error 1130-host ‘192.168.*.*’ is not allowed to connect to this MySql server.
解决：该mysql服务不允许远程连接。进入mysql
mysql> use mysql;
mysql> alter user set host='%' where user = 'root';
mysql>select host,user from user;
mysql>flush privileges;
mysql>exit;
（2）error 1251 client does not support authentication protocol requested by server.
解决：root账户默认的加密方式是caching_sha2_password；很多客户端工具不支持这种加密认证方式，连接的时候就会报这种错。
mysql> use mysql;
mysql> alter user 'root'@'%' identified by 'password_123' password expire never;
mysql> alter user 'root'@'%' identified with mysql_native_password by 'password_123';
mysql> flush privileges;
mysql> exit;
重启mysql服务，再次连接，成功。