下载mysql deb包并解压，
sudo dpkg -i mysql-common_8.0.26-1ubuntu18.04_amd64.deb
1、mysql-common_8.0.26-1ubuntu18.04_amd64.deb
2、mysql-community-client-plugins_8.0.26-1ubuntu18.04_amd64.deb
3、libmysqlclient21_8.0.26-1ubuntu18.04_amd64.deb
4、libmysqlclient-dev_8.0.26-1ubuntu18.04_amd64.deb
5、mysql-community-client-core_8.0.26-1ubuntu18.04_amd64.deb
6、mysql-community-client-core_8.0.26-1ubuntu18.04_amd64.deb
7、mysql-community-client_8.0.26-1ubuntu18.04_amd64.deb
8、mysql-client_8.0.26-1ubuntu18.04_amd64.deb
9、mysql-community-server_8.0.26-1ubuntu18.04_amd64.deb
安装报错提示没有Package mysql-community-server-core is not installed安装包的依赖关系。
安装mysql-community-server-core，提示没有libmecab2，安装依赖包
10、mysql-server_8.0.26-1ubuntu18.04_amd64.deb
安装完成
