|Lesson 10||Perform database recovery with interactive RMAN|
|Objective|| Use Recovery Manager (GUI tool) to recover a failed database. |
Recover Failed Database
Orcle Recovery Wizard
The Recovery Wizard guides you through the process of specifying what you want to restore and recover and submits a recovery job through the Enterprise Manager to complete the operation.
As you already know, RMAN is available in two modes, the line mode and the GUI Mode. Typing RMAN at the DOS prompt of the host machine that has the OEM accesses the command line mode.
The GUI mode is embedded within the Oracle Enterprise Manager (GUI). The GUI mode of RMAN offers the following advantages over the line mode:
- All the defaults are specified one time only, such as:
- Log into RMAN
- Name of the default channels
- Name of the target database and its userid/password
- Location of the backup sets
- The user need not remember all the commands to either back up or recover a database.
- The user need not worry whether any of the steps or commands has been missed during backup or recovery, because both backup and recovery are available in the form of wizards.
- The utilities of OEM are available to RMAN, such as the creation of jobs.
- The endpoint of the wizards can be stored as reusable code.
Recovery Wizard: Recovery Selection
The Recovery Selection page of the Recovery Wizard allows you to select from types of recovery operations that you will see in the SlideShow below. The SlideShow explains the recovery selection process by using the Recovery Wizard for recovering tablespaces and datafiles.
If the database is mounted, but not open, all three options are available. If the database is open and within ARCHIVELOG MODE, only tablespaces and datafiles are available.
The type of recovery you select determines the procedure that the Restore Wizard guides you through.
Perform recovery without restoring the datafiles
A checkbox "Perform recovery without restoring the datafiles" is available. By default, the checkbox is deselected.
If you select the checkbox, a recovery is performed without a restore. The Rename page will not appear if you have selected this option.
Use the "Perform recovery without restoring the datafiles" option if the datafile exists and is not corrupted and the database only requires applying the redo logs to the datafile.
If you want to restore to a point previous to now, you must check the "Until" checkbox and enter a date and time when the date and time fields are activated.
Using Recovery Wizard
The following SlideShow explains the recovery selection process by using the Recovery Wizard for recovering tablespaces and datafiles.
In the following simulation, we will recover a tablespace by using RMAN.
The next lesson concludes this module.