RMAN question

Oracle says that an rman "FULL" backup and an incremental "LEVEL-0" backup are the same except that the "FULL" backup is not part of your Incremental backup strategy. What does this mean when you want to perform a complete database restore and recovery? Will rman ignore a "FULL" backup in favor of the Incremental Level-0 backup? Will it NOT apply other incremental backups (1,2,3..) after restoring a "Full" backup? For example: If I do a Level-0 backup, then a "Full" backup, and then perform a complete database restore and recovery, will rman use the Level-0 or the "Full" backup for the restore? I would like to more clearly understand the purpose of the "Full" backup, when you should use it, and how rman differentiates one from the other when performing a restore. Do you have to employ a "tag" in each of your database backups so you can tell it which to restore? Can someone shed some light on this?

Along the same lines; when you are going to do a database restore & recovery Oracle says you should backup the database in its current form first. If I back it up with rman first and then perform a restore & recovery, won't rman just restore the last backup which is the one I just performed? How do you accomplish this using rman? What are the ramifications given that rman will never backup online redo log files (one could get trashed in a failed recovery)? Do you have to use an O/S tool to back it up before an rman restore/recovery? If so I have to wonder why anyone would bother with rman if you have to setup O/S backups too. Isn't one of the objectives in using rman to eliminate the need for O/S backups (file copies to tape)?

Oracle can't seem to answer these questions for me and they never, ever, manage to find someone internal that knows Recovery Manager. Pretty sad that they can't support their own product. That also is cause for concern in using rman.

Thanks, rwp Received on Sun Dec 12 1999 - 22:38:13 CST