Repair MDF File of SQL Server

SQL Server DBMS and its Importance:

SQL Server is a relational database management system. The product is developed by Microsoft. It is widely used to store huge amount of data. Objects like tables, indexes, views, etc. are used to store data. The MDF file format is used to store SQL database files. Details of any alteration made in the server are stored in the transaction log file. These files are not immune to corruption. It can get corrupted which makes the files inaccessible. A database file of SQL Server may also get damaged if transaction log file gets large and exceeds the size capacity of hard disk.

Other reasons for the corruption include:

• Abrupt system shutdown due to power failure
• To access files when the server is active/running
• Server problems or failure of hard drive
• Exceeds the size limit of the database file
• Accidental removal of log or accidental removal of database files. 

All these reasons lead to corrupted tables, indexes, triggers, views and other objects. 

Steps to Repair MDF File:

A manual approach to repair MDF file is to execute DBCC CHECKDB statements:

1. Dbcc checkdb ('database_name') with no_infomsgs

You do not need to repair file if the above statement is executed without any errors. Before executing the repair operation, you need to set the database in single user mode by executing:

2. Alter database 'database_name' set SINGLE_USER
You can now start repairing process by using Repair_Rebuild model by executing:

3. Dbcc checkdb('database_name', REPAIR_REBUILD)
If this statement executes successfully, then execute 5.5 else execute:

4. Dbcc checkdb('database_name', REPAIR_ALLOW_DATA_LOSS)
This statement may lead to data loss. If it is executed properly then execute 5.5 else execute:

5. 5.1 Alter database 'database_name' set EMERGENCY
5.2 Alter database 'database_name' set SINGLE_USER

5.3 Dbcc checkdb ('database_name', REPAIR_ALLOW_DATA_LOSS) with no_infomsgs, all_errormsgs

5.4 Alter database 'database_name' set ONLINE
5.5 Alter database 'database_name' set MULTI_USER

This manual solution is helpful if the file has minor corruptions and technical knowledge is required to execute this process. One more solution to repair MDF file is third-party recovery software which helps you to recover data from corrupted MDF file. Recovery software is very effective as it repairs highly corrupted file. There are many third-party tools available in the market. These tools are compatible with all the versions of SQL Server application. Effectiveness is the most striking feature of third-party software. Highly corrupted file can be repaired in no time. It is also one of the best reliable solutions.

MS SQL Server Recovery program from SysInfoTools helps you to recover your inaccessible data. It is supported by all the Windows operating systems. It is compatible with all the versions of SQL Server application. You can download and install a free trial version for evaluating the performance of the software.