Consider the following typescript:
# export DEBIAN_FRONTEND="noninteractive"
# sudo debconf-set-selections <<< "mysql-community-server mysql-community-server/remove-data-dir boolean true"
# echo GET mysql-community-server/remove-data-dir | debconf-communicate
0 true
# apt purge mysql-*
...
# echo GET mysql-community-server/remove-data-dir | debconf-communicate
10 mysql-community-server/remove-data-dir doesn't exist
# sudo debconf-set-selections <<< "mysql-server mysql-server/root_password password 123456"
# sudo debconf-set-selections <<< "mysql-server mysql-server/root_password_again password 123456"
# echo GET mysql-server/root_password | debconf-communicate
0 123456
# apt install mysql-server-5.6
...
# echo GET mysql-server/root_password | debconf-communicate
0
So, does debconf-set-selections
does this automatically? Or it's install scripts that do this? Any other option?