Thursday, March 17, 2011

SQL Recovery to Handle Transaction Log Corruption in SQL Server

Microsoft SQL Server records all the database transactions in transaction log. Transaction is an operation that you perform on the database that can be read, write, modify, or delete. However, in some situations, an SQL Server operation that requires to process or read transaction log may fail due to corruption. The corruption usually leads to data loss and put you in need of SQL database recovery solutions.

When the operation fails, you may encounter the below error message that indicates that transaction log is damaged-

Error: 9004, Severity: 21, State: 1.
An error occurred while processing the log for database 'mydb'. If possible, restore from backup. If a backup is not available, it might be necessary to rebuild the log.


The State number of the error may vary for the error and indicates what is the type of corruption. To sort out this problem and perform SQL recovery, you must find the cause of this issue.

Root of the problem-

Error 9004 usually occurs due to corruption to the transaction log of Microsoft SQL Server database. The causes for the transaction log inconsistency are similar to the database corruption issue detected in MDF (Microsoft Database File) by DBCC CHECKDB command or SQL Server Engine. In order to identify y the actual reason of the corruption, you must follow similar techniques for the database corruption including file system and hardware analysis.

Resolution-

As stated above in the error message, you are required to restore the database from the most recent backup to recover SQL Server database. This is the most efficient and easiest SQL Server recovery solution.

If you do not have an updated backup in place, then you should run DBCC CHECKDB command on the database. It is an inbuilt tool of SQL Server that checks and fixes database inconsistency issues.

In case none of the above methods work, SQL recovery software come for your rescue. Third-party SQL database recovery applications are totally safe and easy to use with read-only conduct and simple graphical user interface.

Such applications effectively handle all database corruption issues. They work with all sizes of the database of Microsoft SQL Server 2008, 2005, and 2000. In order to ensure absolute SQL repair, you are highly recommended to use an advanced tool, such as Stellar Phoenix SQL Server Recovery.