RMAN Backup recovery and DATA PUMP

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RMAN
Backing up all or part of your database is accomplished by using the BACKUP command from within the RMAN client.
RMAN uses the configured settings and channels for your database, the record of previous backups in the RMAN repository and the control file's record of the structure of your database to determine an efficient set of specific steps to perform in response to a BACKUP command.
RMAN's BACKUP command supports backing up the following types of files:
• Database files, including datafiles, control files, and the server parameter file (SPFILE)
• Archived redo logs
• Other backups created by RMAN, including such as datafile and control file image copies, and backup sets containing SPFILEs, control files, datafiles and archived logs.
RMAN backups of datafiles can be either full datafile backups, or incremental backups.
A full backup of a datafile is a backup that includes every used data block in the file. If a full datafile backup is created as an image copy, the entire file contents are reproduced exactly. (If backing the datafile up to a backup set, then unused blocks may be skipped.
An incremental backup of a datafile captures images of blocks in the datafile changed since a specific point in time, usually the time of a previous incremental backup. Incremental backups are always stored as backup sets. The resulting backup sets are generally smaller than full datafile backups, unless every block in the datafile is changed. RMAN can only create incremental backups of datafiles, not of archived redo log files or other files.



DATA PUMP
Oracle claims Data Pump offers a transfer of data and metadata at twice the speed of export and twenty to thirty times the speed of the import utility that DBAs have been using for years. Data Pump manages this speed with multiple parallel streams of data to achieve maximum throughput.
Data Pump consists of two components: the Data Pump export utility called “expdp,” to Export the objects from a database, and the Data Pump Import utility called “impdp,” to load the objects into database. Just like traditional export and import utilities, the DBA can control these jobs with several parameters.

SYSTEM REQUIREMENTS
System Requirements
The successful running of any project primarily depends upon hardware and software used in its compilation. The hardware used in the machine should be such that it supports the software that is to be mounted for assembling the project. This project deals with the hardware and software, which is available readily and easy on each and every machine given to the user.



Advantages

You might come across so much blah-blah on RMAN from ever so many DBAs and sysadmins who are just as exuberant with the new discovery. However, as the official recovery tool recommended by Oracle Corporation, RMAN has its place among the forefront of recovery and backup tools for the Oracle database. Personally I feel these are the advantages::
1. Direct backup to tape is possible.
2. Flexibility to first backup to disk and then use a DVD writer.
3. Speed. It's the second quickest after OS file copy. In the examples shown, the speed was close to 4.5 MB per sec. The whole database was backed up in 2'01" flat!
4. Flexibility to use multiple channels (in Enterprise version only). Even without, RMAN is very quick.
5. Very clean procedure, no nagging details such as in export.