...php/mysql knowledge to use it? am quite a novice in database driven web design, and i want to try out joomla. i have no knowledge on php or mysql

Well most of the PHP/MySql CMS systems will need you to have some experience with PHP and MySql to be highly effective, but not to just use one. Once installed and running you really don't need that unless the site errors for some reason.

Since you want to learn why don't you download it and run it locally. You can easily install your own web server on your computer and then learn locally.

Or download it and install it on your web server in a sub directory and play. learn, design away!

The best way is DIG IN! Joomla is not too hard to learn. The setup is fairly easy and in some cases even automated so just install it and see. You will surprise yourself.