I know that osb backup software is faster than other vendor software especially oracle database backup area.
There are two special method (Unused block compression and Undo backup compression)
But, normally in case of comparable product using same RMAN API(Veritas/Legato etc...), they only backup used block and skip unused block, right?
I'm confused, what is different from used block only backup and unused block compression.
Please explain detail about unused block compression and Undo backup compression.