Quote:
Originally posted by vinit
Hi modic,
do you mean to say that RMAN will know the size of the datafiles when performing a cold backup and not during a hot backup ?
I thought RMAN could do a backup on raw devices irrespective of the type of backups.( Hot/cold).
No, the datafiles are not a problem, their size remains static (well, at least in most cases) during backup. But when RMAN performs a hot backup, the backup set consists of datafiles, controlfiles and archived redolog files. Controlfiles can grow during backup. But more importantly, when RMAN starts performing hot backup, it doesn't know how many archlogs will be generated during the backup time and what their exact size will be! Archlogs generated while performing the backup *must* be included in the backup set, otherwise the backup set will not be complete.