How to Repair MDF Files in SQL Server Database

Introduction

SQL database has two major files: MDF, NDF, and LDF file. MDF file is the main database file that contains tables, indexes, stored procedures, views, etc. The NDF file is the secondary database file. Along with these database files, there is another file type called an LDF file. It is of utmost importance because it stores every modification made in the database. It contains all transactions.

When your database gets corrupted, you become unable to access the information available on the server. So, it becomes necessary to repair these files so that you can restore your database and access all the information available. Now, the question is, ‘how to repair MDF files in SQL server databases’?

Before learning the techniques, let us first take a look at some prominent reasons why MDF files get corrupted.

Also Read: Manual Method to Restore SQL Database without Transaction Log File

Why Need to Repair Corrupt SQL MDF File?

• Virus attack is one of the major reasons for database file corruption.
• If there is some hardware issue like hard disk crash or memory issue, MDF files are more likely to get corrupted.
• Abrupt shutdown of the system affects the running processes which ultimately leads to database file corruption.
• Sometimes, human errors like unnecessary command execution also cause MDF file corruption.

There are even more reasons for the SQL database MDF file corruption. However, these are some of the most common causes. Now, it is time to check how to fix the database MDF files.

How to Repair MDF Files in SQL Server Database?

Manual Way to Repair Corrupted MDF File

• Open SQL Server Management Studio (SSMS).
• Execute the following command, replacing YourDatabaseName with your database’s name and specifying the path to your backup file:
  • RESTORE DATABASE YourDatabaseName
  • FROM DISK = ‘FULL_PATH_OF_BACKUPFILE’
  • WITH REPLACE;

Use the DBCC CHECKDB Command:

The DBCC CHECKDB command is designed to check the integrity of SQL Server databases and can repair minor corruptions. Here are the steps to repair MDF file manually:

• Set the database to emergency mode:
  • ALTER DATABASE YourDatabaseName SET EMERGENCY;
• Execute the DBCC CHECKDB command to identify issues:
  • DBCC CHECKDB (YourDatabaseName);
• If errors are found, set the database to single-user mode:
  • ALTER DATABASE YourDatabaseName SET SINGLE_USER;
• Run the repair command, choosing the appropriate repair level (e.g., REPAIR_REBUILD or REPAIR_ALLOW_DATA_LOSS):
  • DBCC CHECKDB (‘YourDatabaseName’, REPAIR_REBUILD); or
  • DBCC CHECKDB (‘YourDatabaseName’, REPAIR_ALLOW_DATA_LOSS);

• Set the database back to multi-user mode:
  • ALTER DATABASE YourDatabaseName SET MULTI_USER;
• Run DBCC CHECKDB again to ensure all issues are resolved:
  • DBCC CHECKDB (YourDatabaseName);

Professional Solution to Repair MDF Files in SQL Server Database

DRS SQL Database Recovery Tool is the most reliable and effective solution to repair corrupt SQL MDF files and restore maximum data. This application provides all the required functionalities that help users easily recover their data. Also, you can manually select what item you want to recover. So, you can exclude all the unnecessary items. Moreover, the application is compatible with all versions of Windows OS.

Steps to Repair MDF Files

• Download and run the DRS SQL Database Recovery Tool as administrator.
• Click on the Open button and then the Browse button. Choose the corrupted MDF file.
• After that, select the Recovery mode and other options as per your need. Press OK.

• Check the preview of the recovered items and hit the Save button to save the data.
• Opt for the mode of Authentication: Windows Authentication or Server Authentication.
• Choose the other migration options and click on the OK button.

Also Read: Repair Access Database – Compact & Repair Utility

Conclusion

I hope after reading this article, you have learned how to repair MDF files in SQL server databases. We have discussed the manual method as well as a professional tool to repair the corrupted file. The manual method is effective to fix minor file corruption. Whereas, for major issues, we recommend you opt for automated software for complete database file recovery.

About The Author:

Shivam Rathore

Shivam is a digital marketer and technical content writer at DRS Solution®, specializing in topics like databases, email recovery, and migration solutions. He enjoys researching and crafting content that assists database administrators, businesses, and beginners in resolving various issues related to MS SQL, MySQL, and Microsoft Exchange.