Overview
As many companies rely on SQL Server Database for the storage of their data, database administrators need to make sure that the database is made available whenever required without failure. In order to ensure that, he/she needs to make sure that the data integrity is maintained all the time and the database files is free from corruption issues. As any other file formats, SQL Server Database files can be corrupted, which may even lead to permanent loss of data. In the content, we will be focusing about the corruption issues and learn ways to prevent Corruption in SQL Server.
About SQL Database Corruption
The top most priority among all the concerns that DBAs needs to be worried are disaster prevention and recovery of SQL Server Database. The SQL Server Database is said to be corrupt state if a problem arises with the improper storage of the actual zeroes and ones required to store data at disk or I/O subsystem. Corruption can also be caused by errors or failures in the storage media or the irregular system shutdown. There can be several reasons behind the database corruption:
Causes of SQL Database Corruption
Following are the database corruption causes:
- Almost all the causes of corruption in SQL Server Database is related to issues at the IO subsystem level i.e., problems related to drives, controllers and even drivers.
- One thing to keep in mind is to use disk-check utility (CHKDSK) available in most of the systems to scan bad sectors, modifies entries or other storage issues that can lead to corruption.
- SQL Server depends on disk system to store/retrieve data, which is why most of the disk related issues leads to corruption.
- Another reason are usage of Anti-virus or Kernel drivers can lead to corruption that is why Experts recommend to exclude SQL Server database files at the time of anti-virus scans.
- Keeping SQL Server Database files in compressed format to conserve disk storage increases the chance of making files corrupted.
It should be kept in mind that the SQL Server Database is going to be corrupted one day or another. It is just the matter of when it is going to happen. So it is better to prepare a plan for preventing SQL Server database from corruption.
How to Prevent Corruption in SQL Server database ?
Though it is not practically possible to prevent corruption in SQL Server Database, we need to know how to deal with them to ensure data availability and uptime of data even when corruption occurs. SQL Server even accepts the disk system errors and provides functionality to address corruption when it occurs. Accordingly, with the help of these functions, it is possible to protect against the consequences that corruption might cause. The best way to deal with database corruption in SQL Server is to be able to detect it at the earliest time possible and address it before it is too late.
In some of the cases, it has been found that corruption that has been encountered go unnoticed for long time if the pages or locations has not been queried that were affected by corruption. Let us create a scenario where a database containing sensitive data is in corrupt state. In this database, user writes data almost every day and the data is not queried regularly, as it done only after every 2 months. It is quite possible that the corruption in this database can go unattended for more than a month. If the organization uses rolling backups, it may hamper the ability to address the corruption problem since backups that could have been used to recover from this problem will have been lost. However, if the problem was noticed earlier in just a few days after its occurrence, the corruption issues are likely to be addressed and resolved soon.
Hence, the most important thing that we need to know while dealing with corruption issues in SQL Server Database is to have possibilities to resolve them, which is available only when the corruption is discovered at the early stage. Otherwise, it may become quite difficult to deal with such issues.
Conclusion
In most of the organizations, corruption cases do not only bring risks to data but also bring negative impact to the business flow and revenues. Database Administrators should be able to find ways preventing Corruption in SQL Server. Even if the database is in corrupt state, they should be able to detect the corruption at the earliest time to take required actions for the prevention of permanent data loss. Regular backups needs to be taken, as it provides one and only way to restore data in case of any disaster. The article has been aimed to focus on the corruption in SQL Server Database and approaches preventing corruption in SQL Server in an efficient manner. However, if despite applying all possible fixes one doesn't succeed in preventing SQL Server corruption then going with SQL database recovery software is best to overcome the data loss.
