Use of backing up a single tablespace or datafile

Hello,
I am reading the RMAN manual and I'm quite familiar with backup up a tablespace or datafile, but I can find very few uses for that. Backup up a tablespace is useful for TPITR, but since that needs another instance its of very little use in most production environments. I think you cannot restore an old version of tablespace in a normal database, unless the tablespace has long been made read-only, in which case RMAN's optimizations will do the trick.
Even less use I can find for datafile backup. I have absolutely no idea what you can do with a single datafile.
Can you please clarify me on the uses of these RMAN features?
Thank you.

Dear Albi!
Think of the following scenario:
You have a very large (let's say 1 Terabyte) production database that is split into n tablespaces. This database is in archivelog mode and a full backup of the hole database would take more than 10 hours.
scenario end.
In such a scenario I think you will not take a full database backup very often. Therfore you can backup portions (tablespaces and datafiles) of your database. This will take less time then a hole DBbackup.
If you have to restore your DB then RMAN will take all the files it needs from all your backup. RMAN uses always the most actual version of your datafiles. After the restore RMAN will take the archivelogs to recover all datafiles to the most actual point in time. And that's the point why partial backups of your db are not only usefull for TSPITR.
I hope I could make clear what the operative point is with partial backups.
Yours sincerely
Florian W.

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EdStevens wrote:
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Edited by: user496996 on Apr 18, 2011 9:25 AM

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