Making that change in phpmyadmin wont stay after a reboot. If you add the line as SUDO to your my.cnf, you should only ever have to restart it once, aside from regular server reboots, but it will always stay
add to the bottom of my.cnf by editing it using sudo nano /etc/mysql/my.cnf
Code:
[mysqld]
sql_mode=NO_ENGINE_SUBSTITUTION
restart mysql server
Code:
sudo service mysql restart