Hi!
Inorder to perform a full database backup of the production database to disk and to overwrite it automatically at the end of week(when I backup the file to tape) so that I retain only 1 week's worth of backup on disk, can I use the command,

backup database dbname to devicename with noinit, retaindays = 7

What exactly is the difference between init/noinit, format/noformat? Is is always better to define the media name, description, backup set name,... when backing up to disk?

Thankyou
Praveena