Link : http://amarok.kde.org/wiki/MySQL_HowTo#MySQL_Setup
Create a root password for MySQL, if you have not already done so.
$ mysql -u root
Of course change xxxxxx to the password you want.
Once you have done that, you must create a MySQL database and a user for amarok for through any usual method. You can just use the "mysql" command: (it will ask for your MySQL root password)
$ mysql -p -u root
In the above example, a database called "amarok" and a user called "amarok" were created. This user can access the database from localhost using the password "PASSWORD_CHANGE_ME". To allow access from remote hosts, use amarokuser@'%'.
It is very important that you 'GRANT ALL' privileges to user "amarok". In particular, "amarok" needs ALTER privileges on its database.
Once a database exists, open the Configure Amarok screen (found in the Settings menu), and go to the Collection tab. Change the drop-down menu from SQLite to MySQL. You will have to specify the host ("localhost" if the database is in your local box), port (3306 is the common value), and the name of the database that you have created for it ("amarok" in our example). Additionally, the username and password of a user who has write access to the given database needs to be specified (in our example, the user is "amarok", and the password is "PASSWORD_CHANGE_ME").