In this article, we will first discuss why regular backups are so important for SQL Server database disaster recovery. Then we will introduce the way to keep backups in good conditions and how to respond to database corruptions.
SQL Server Database Disaster
One should know that disasters related to SQL database management are highly unpredictable. What’s more, you cannot avoid them from happening. The best you can do is stay prepared for the worst situations. That’s why the best measure any admin can take to mitigate the damage caused by sudden unexpected surprises is to keep backing-up the data.
Why Create Backups?
We already established that the best defense mechanism against data corruptions and critical errors is to keep backing-up the database. It’s true that there are certain errors/problems that can easily be fixed even if you don’t have back-ups handy. But, backups are your safety net and one should always have them as part of precautionary measures. Also, the problems that are easily fixable have nothing to do with I/O subsystem. Those problems mostly involve meta-data getting out of sync or becoming outdated.
Reason why database administrators should create backups is because the way data is stored is a highly complex mechanism. And, one should remain prepared for the all sorts of problems. The only way to achieve that is to have copies of data stored somewhere else to use as backup in case of emergencies.
Backups – Integral to Disaster Recovery Plans
Disasters can happen without any previous warnings. So, you must prepare for them beforehand. The same logic applies to disasters that can happen with an SQL server database. Part of this disaster recovery plan is to have backups. It is also worth noting that many users confuse High Availability as a replacement of backup.
One may assume that a backup is all he/she needs. But, that’s not enough. Other than creating them from time to time, it’s equally important that you verify them. Verification helps make sure that they are valid, functional, and actually helpful in restoring the data.
Respond to Database Corruptions
There are certain corrective measures one can take as a way to bring down the possibility of data loss. The steps are also helpful in reducing the downtime that happens due to corruptions. Also, not all disasters carry the same magnitude and level of impact on data.
Some corruptions happen within data page that store the data required for database to keep running. Others happen to indexes or simple structures. These kinds of errors are easily fixable in steps as simple as dropping and recreating the index. Fixing these problems doesn’t result in any major downtime except for few minor disruptions.
However, some corruptions happen within key pages that database uses to MAP the data, indexes, and find key structures. So, if something bad happens with some critical pages, those corruptions can be fatal. The only solution in these situations is to resort to backups.
Database Recovery Software
In case your backups fail to offer you any real help, you can always use SQL Server recovery software. Be sure to go through full-fledged details of the software to make sure it matches you particular requirements.
Peter Song is a data recovery expert in DataNumen, Inc., which is the world leader in data recovery technologies, including outlook recovery and PDF recovery software products. For more information, visit www.datanumen.com.