Why and when should I backup my database? (for DBA

Why and when should I backup my database? (for DBA
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1 Answer

Answer :

Backup and recovery is one of the most important aspects of a DBAs
job. If you lose your company's data, you could very well lose your job.
Hardware and software can always be replaced, but your data may be
irreplaceable!
Normally one would schedule a hierarchy of daily, weekly and monthly
backups, however consult with your users before deciding on a backup
schedule. Backup frequency normally depends on the following factors:
. Rate of data change/ transaction rate
. Database availability/ Can you shutdown for cold backups?
. Criticality of the data/ Value of the data to the company
. Read-only tablespace needs backing up just once right after you
make it read-only
. If you are running in archivelog mode you can backup parts of a
database over an extended cycle of days
. If archive logging is enabled one needs to backup archived log files
timeously to prevent database freezes
. Etc.
Carefully plan backup retention periods. Ensure enough backup media
(tapes) are available and that old backups are expired in-time to make
media available for new backups. Off-site vaulting is also highly
recommended.
Frequently test your ability to recover and document all possible
scenarios. Remember, it's the little things that will get you. Most failed
recoveries are a result of organizational errors and
miscommunications.
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