Fix SQL Corrupt Transaction Log

Microsoft SQL Server is one of the most popular database client applications that is widely used by individuals as well as organizations. But it is vulnerable to corruption that may be the result of logical as well as physical reasons. Sometimes problems arise due to SQL corrupt transaction log which makes the entire data stored in the database inaccessible leading to severe data loss situations.

The SQL corrupt transaction log can be rebuilt to recover the database with the help of the SP_ATTACH_DB_SINGLE_FILE_DB command. This command can help in the following ways:

  • Use SP_ATTACH_DB_SINGLE_FILE_DB command on the MDF file that were detached previously from the server through the SP_DETACH_DB command.
  • Use SP_ATTACH_DB_SINGLE_FILE_DB command on the MDF file that has only one log file.

But when the command does not help you to recover the inaccessible data stored in the database you need to follow the steps mentioned below:

  • Create backup of the file.
  • Separate the corrupt database from the server with the help of the SP_DETACH_DB command.
  • Create new database file that has the same name as the corrupt database file. Ensure that the file has the path where the log files are stored.
  • Stop the SQL Server services.
  • Rename the new database file without mdf extension.
  • Rename the corrupt database file as the new database file.
  • Start the SQL Server services.
  • Open Query Analyzer, run SP_CONFIGURE 'allow updates',1
  • When allow updates is set to 1 using sp_configure system stored procedure, then you need to use RECONFIGURE WITH OVERRIDE statement.
  • Update SYSDATABASES system table.
  • Restart the SQL server services.


However, it must be noted that the aforementioned steps are tricky which could lead to the permanent loss of data. To avoid such a situation you can make use of an efficient and reliable third party MDF repair software that can perform complete SQL recovery by repairing the SQL database and all its objects and get rid of the data loss situation caused due to SQL corrupt transaction log.