Originally posted by kris123

I just thought RMAN output would be a compressed one like export.
I get 2.5gb when i exported the whole db. but rman got 15gb.

of course. rman is a backup. it includes data, indexes, free space, etc. exp is a dump of your data only.


does it copy the whole file systems?

yes


how about large temp and rbs
tablespaces that doesnt have data contents or data tablespaces that
have few or no tables yet.
temp, maybe yes maybe no. depends on how you have created it.

rbs, absolutely. This is crucial for a valid recovery.

empty tablespaces, maybe yes maybe no. rman doesn't backup blocks that were never used, but does backup blocks that were used at one time but are empty now.