Backup Database Help

Could you tell me how to make my backup files not overwrite each other? Right now I have a job setup to run a backup everyday at 12am, but when I arrive in the morning there is just one file in the folder. I want it to read like this (BUP_Master_12/11/07 12:00am, BUP_Master_12/12/2007 12:00am…). I want to see a file for everyday. Anyone know what to do? (getdate???)

How do you start the backup, from unix cron?

Rename the files before the backup start
or
Have your script dump to different file names

Include date in file name so that file name will not be overwritten