Recover without updating
The control file autobackup has a default file name that allows RMAN to restore it even if the control file and recovery catalog are lost. corrupt block An Oracle block that is not in a recognized Oracle format, or whose contents are not internally consistent.Typically, corruptions are caused by faulty hardware or operating system problems.When block change tracking is enabled, RMAN uses the record of changed blocks from the change tracking file to improve incremental backup performance by only reading those blocks known to have changed, instead of reading data files in their entirety.initialization parameter is enabled, then the database calculates the checksum for every data file or online redo log block and stores it in the block header when writing to disk.Crash recovery only requires redo from the online logs: archived redo logs are not required.
crash recovery The automatic application of online redo records to a database after either a single-instance database crashes or all instances of an Oracle Real Applications Cluster configuration crash.The closed backup A backup of one or more database files taken while the database is closed.Typically, closed backups are whole database backups. You do not need to apply redo to this backup to make it consistent.For example, if you back up logs in the fast recovery area that RMAN determines are corrupt, RMAN can search for logs in other archiving locations and back them up instead if they are intact.asynchronous I/O A server process can begin an I/O and then perform other work while waiting for the I/O to complete while RMAN is either reading or writing data.