1. Stop MySQL using the following command:
    sudo /etc/init.d/mysql stop
  2. Copy the existing data directory (default located in /var/lib/mysql) using the following command:
    sudo cp -R -p /var/lib/mysql /newpath
  3. edit the MySQL configuration file with the following command:
    sudo gedit /etc/mysql/my.cnf # or perhaps /etc/mysql/mysql.conf.d/mysqld.cnf
  4. Look for the entry for datadir, and change the path (which should be /var/lib/mysql) to the new data directory.
  5. In the terminal, enter the command:
    sudo gedit /etc/apparmor.d/usr.sbin.mysqld
  6. Look for lines beginning with /var/lib/mysql. Change /var/lib/mysql in the lines with the new path.
  7. Save and close the file.
  8. Restart the AppArmor profiles with the command:
    sudo /etc/init.d/apparmor reload
  9. Restart MySQL with the command:
    sudo /etc/init.d/mysql restart
  10. Now login to MySQL and you can access the same databases you had before.