http://demo.phpmyadmin.net/STABLE/?pma_username=root. This is an online phpMyAdmin installation that allows you to create databases and practice the administration of the phpMyAdmin system online for free. if you want to practice MySQL queries and do not want the hassle of installing a huge package like SQL server 2012 or MySQl; then this is perfect. MySQL underpins nearly all online websites so practicing and understanding how to create a simple database and tables is very useful. This will help you. Especially if you are on an Internet cafe computer and it does not allow you to install any SQL software. The SQL DROP TABLE query is disabled; so you can not go on a deleting spree. But the ability to practice SQL on any computer connected to the Internet is a bonus. So give this a try and see if you like phpMyAdmin or not.
The username is root and the password is blank. Just login and start practicing SQL queries right away.