kenny@kenny-OptiPlex-790:/etc/apt/sources.list.d$ sudo dpkg --remove --force-depends mysql-community-server
dpkg: mysql-community-server: dependency problems, but removing anyway as you requested:
 mysql-server depends on mysql-community-server (= 5.7.12-1ubuntu15.10).
 akonadi-backend-mysql depends on mysql-server-core-5.6 | virtual-mysql-server-core; however:
  Package mysql-server-core-5.6 is not installed.
  Package virtual-mysql-server-core is not installed.
  Package mysql-community-server which provides virtual-mysql-server-core is to be removed.

(Reading database ... 260163 files and directories currently installed.)
Removing mysql-community-server (5.7.11-1ubuntu15.10) ...
update-alternatives: using /etc/mysql/my.cnf.fallback to provide /etc/mysql/my.cnf (my.cnf) in auto mode
Processing triggers for man-db (2.7.4-1) ...
kenny@kenny-OptiPlex-790:/etc/apt/sources.list.d$