I couldn't find any solutions how to install mysql-5.6 in a docker container non-interactively. I found the following commands but they need user input:
# Update the repo list, execute :
wget http://repo.mysql.com/mysql-apt-config_0.2.1-1debian7_all.deb
dpkg -i mysql-apt-config_0.2.1-1debian7_all.deb
# Install
apt-get update
apt-get install mysql-server-5.6
Is there a better solution for non-interactive installation?