The three basic kinds of recovery are:
1. Recover database - here you use the recover database command and the database
must be closed and mounted. Oracle will recover all datafiles that
are online.
2. Recover tablespace - use the recover tablespace command. The database can be
open but the tablespace must be offline.
3. Recover datafile - use the recover datafile command. The database can be open but
the specified datafile must be offline.
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