For forcefully purging the package.
Since removing packages can be destructive, print the list of the package that will be removed:
dpkg -l | awk '{print $2}' | grep -i mysql | grep -v lib
Check if any important package is being removed. If everything seems fine, proceed to step 2.
Purge the packages:
sudo dpkg -P --force-all $(dpkg -l | awk '{print $2}' | grep -i mysql | grep -v lib)