wget http://repo.mysql.com/mysql-apt-config_0.8.10-1_all.deb
sudo dpkg -i mysql-apt-config_0.8.10-1_all.deb
sudo dpkg-reconfigure mysql-apt-config
sudo apt update
sudo apt-cache policy mysql-server
sudo apt install -f mysql-client=5.7.30-1ubuntu18.04
sudo apt install -f mysql-community-server=5.7.30-1ubuntu18.04
sudo apt install -f mysql-server=5.7.30-1ubuntu18.04
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