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What Is Database Disaster Oracle

Recovery?

Created by Larry Ellison, Ed Oates and Bob Miner, the Software Development Laboratories in 1977 developed the original Oracle DBMS (or Database Management System.) The name Oracle is derived from the code of a project that they worked on at Ampex.

Software Development Laboratories was then renamed to

Relational Software Inc. (or RSI) in 1979 D which was later named Oracle Corporation in the year 1984.

The two major components of an Oracle DBMS are Database and Instance. The Database contains all the control files; redo logs (that contain your data and Oracle metadata), and physical data files. The control files contain Oracle metadata which are very important and contain all the information that is needed to access the database. The redo log holds records for any changes that have been done.

An Instance, however, is a combination of the background processes and the pool of physical memory called RAM allocated to Oracle. The RAM is also called System Global Area (or SGA.) The RAM is employed to cache data (since the RAM is a thousand times faster than I/O.)

There are different types of backups, namely: whole Database Backup, Consistent Whole Database Backup, Inconsistent

Whole Database, Inconsistent Closed Backups, Tablespace Backups, Datafile Backups, and Control File Backups. Each backup differs the others, and knowing which backup method should be used is essential.

RMAN (or recovery manager) is a component that establishes a connection with a particular server process. The RMAN

automates the flow of data for recovery operations and backup.

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The OS (or Operating System) is another process but one where the database is backed up manually by a specific command execution to certain user specifications.

The Oracle export Utility, however, makes backup logical by writing data from the Oracle database to OS files. The Oracle Enterprise Manager, on the other hand, runs with a GUI interface that brings Recovery Manager to work.

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How to Survive Data Recovery Disaster

Sometimes, even with a team of Data Recovery Disaster specialists on your side helping out, it may not be possible to foresee when Data Recovery Disaster will strike. Sometimes, it may seem like fate is playing a cruel joke on you and Data Recovery Disaster occurs despite your best efforts. Can you survive a Data Recovery Disaster event?

If you are a business organization hit by a Data Recovery Disaster event, one thing you do not need is unwarranted publicity.

This is because you need clients to think that they can trust you with their data and their business. This is why many corporations hire PR firms to ward off nosy reporters who only see the value of a potential story and do not see why corporations would want to shield themselves from publicity. Until you have found out what caused the a Data Recovery Disaster event to occur, it would be wise to keep the media at bay D once you know why the event happened and how you can prevent it and other threats from occurring, then you can safely talk to the press (but definitely not beforehand.)

This means you have to exert all efforts to find out the true causes of the event. For instance, if your data storage facility was hit by a fire, you should always get an investigating team that specializes in fire damage to assess what the cause was. You might be unpleasantly surprised that arson could have been a factor D

possibly motivated by business competition. Or, if it seems like someone downloaded a virus into the IT system accidentally, you may want to investigate the background and work records of that employee D there are cases when disgruntled employees sabotage

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their employer and the organizational IT systems deliberately. It is not paranoia if they are really after you.

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