phpMyAdmin is a wonderful tool to work with mySQL and whenever I am developing with mySQL I find that I am using it all the time. Now I would not advise to use phpMyAdmin on your production server but for development it sure is very convenient.
For developing I have set up a virtual machine running Ubuntu Linux 14.04 and this is where the mySQL server and phpMyAdmin lives. While phpMyAdmin is very handy the session time out (by default it is 30 minutes) is a bit short and so you will find you have to login all the time because your session expired.
The way to fix this is to add the following line to config.inc.php which you can find in the phpmyadmin directory (on my machine this is /etc/phpmyadmin/ ):
$cfg['LoginCookieValidity'] = 28800;
The number 28800 is the new timeout in seconds. This will set the session time out to 8 hours. So no more of those pesky timeouts in phpMyAdmin.