
Backup and Recovery
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STARTUP MOUNT
Mounts the database (identified by dbname) but does not open it.
Strictly speaking, STARTUP MOUNT is not a SQL statement, but
it is issued from SQL*Plus.
STARTUP MOUNT dbname
You must use this command to perform a user-managed recovery
operation.
Recovery Manager
RMAN is a facility provided by Oracle to manage hot and
cold backups and the associated archive files.
WARNING
RMAN provides support only for hot and cold backups.
It does not support exports or imports.
RMAN maintains a separate recovery database of all files
necessary to recreate the Oracle database as it was at a partic-
ular point in time. It also maintains information about the
location of the files. RMAN also allows you to perform incre-
mental hot backups. It is able to look at each data block,
determine whether it has changed since the time of the last
backup, and write out only those blocks that have changed.
This feature can significantly reduce the amount of time and
storage required to back up a large database.
While RMAN helps automate the recovery process, you are
not required to use it. DBAs have been successfully backing
up and restoring databases without RMAN for years. There
are also several third-party tools available that provide sup-
port for backing up databases.