Help! I lost my password!
If you log on as a superuser, you can see all of the usernames and reset any password you do not know. If you do not know the username or password of any superuser then you can find it by looking at the actual Users table in the database (you would most likely need to use a MySQL GUI to do this- Navicat or MySQL Administrator). If you know the password for a non superuser then you can make that user a superuser through the MySQL GUI program by changing the user's permission level to 5.
If you do not know the username or password for any user, there is no way to access the data without using the source code and programing a way around the password requirement. For security purposes, passwords are not stored in the database.