I've been asked to make a script or cron job that will backup a database we access through php admin. I can physically go there and choose to export a copy of the database and that is what I would want the script or cron job to do?

Can anyone give me something to work with. If I could find out the syntax for opening a program and manipulating elements inside the program, I can probably put something together.
If someone can help me or point me in a direction of getting information to accomplish this task I would really appreciate the help!