Repair MDF File in SQL with Best How to Tutorial (2023)

Mohit Jha ~ Modified: May 23rd, 2023 ~ SQL Server ~ 10 Minutes Reading

Repair MDF File in SQL with Best How to Tutorial (1)

MDF File which is the master database file is the primary data source of the SQL Server. Now, users often come up with queries & asks to repair MDF file in SQL Server. When we look deeper into this scenario, we can find out that there could be several reasons for the corruption. Moreover, various solutions for the same are there as well.

In this guide, we are going to explore manual & modern solutions along with their respective benefits & drawbacks. Before we step in, let’s go through some of the user queries explaining their miseries about this issue.

Hey there, I was trying to run some operations in a running SQL Server. I don’t know how but my MDF files are now corrupted & I don’t have any NDF file or backup data. Please suggest any solution for the damaged MDF repair task to me. I’ll appreciate any help in this case.
James Shelby, USA

I just realized my MDF files are corrupted & I don’t even know what’s wrong. Please help me fix the database anyhow. I just want to know how to repair SQL MDF file in the easiest manner possible. I’m ready to purchase any tool but all I need is my database back in a healthy state.
Henry Clark, USA

Table of Content

  • Reasons for MDF Corruption
  • All Manual Solutions
  • DBCC CHECKDB Command
  • DBCC Command Drawbacks
  • Experts-Rated Solution
  • Automated Features of Tool
  • Software Specifications
  • Tips to Eliminate Errors
  • Conclusion

Need to Repair SQL MDF File – Reasons for Corrupted MDF

First of all, let’s understand what an MDF file is. It will make things easier for us further. So, the MDF file in SQL Server is the primary or master database file that contains both data & database schema. Therefore, it is so valuable. It holds all the SQL objects like tables, triggers, views, rules, functions, stored procedures, etc.

(Video) How to import(Restore) an mdf file into SQL Server

There can be several reasons being a damaged MDF file. We can classify the reasons into Logical & Technical parts as shown below:

Logical Reasons for Corruption of MDF File

  • Using SQL Database with a compressed file is a common reason.
  • Improper upgrade of the server also results in corruption of files.
  • The MDF file gets corrupted in case the file header is damaged.
  • Damages to the storage medium where the MDF file is stored.
  • Network errors occur in the middle of a running SQL Server.
  • Hard drive failure, sudden power failures, virus attacks, etc.

Learn How to Repair MDF File Due to Technical Reasons

  • Not enough space in the drive where MDF file is stored. Without the NDF file, the primary database will get no space to store data & will surely get corrupted.
  • If a user tries to copy data in a running SQL Server, the MDF file might get corrupted. Moreover, the commencement of any operation in a running SQL server is risky.
  • In case the LOG file or the LDF file is already corrupted, it will affect in damaging the MDF file as well. This is due to the inter-relations of both these files.
  • In the 2000s, when the Jet engine crashes issues were quite common. Similarly, when the SQL Server search engine crashes, the MDF files also get corrupted.
  • Change of Service Account password but not updated in the SQL Server is also a major reason for damage in the master database file of the SQL server.
  • When startup parameters have incorrect file path locations, it is likely to result in a corrupt master database file of the SQL Server.

Also Read: How to Check Database Corruption in SQL Server Safely?

Repair MDF File with Manual Solutions – All the Options We Have

Most of the users often try to get a manual solution as in their opinion, it’s a free as well as an easy way. However, this is just the tip of the iceberg. There is a lot more that users need to know about the manual solution.

First of all, there are two manual solutions available for users:

  • DBCC CHCEKDB Command
  • Recovery from Backup File

Now, most users do not have any backup files & this is why they often get stressed. if hey have backup, they can restore SQL Server database from MDF files easily. In case, users are equipped with a backup file, they can imply restore their database using that backup.

On the other hand, if users do not possess the backup file, they need to learn how to repair SQL MDF file using the DBCC command. Let’s explore this solution along with its drawbacks followed by the experts’ trusted automated solution.

DBCC CHECKDB Command for Damaged MDF Repair

If users are very well proficient with the commands of SQL Server, they can simply use the DBCC command line method. Follow the below-mentioned steps to learn this method in-depth. Also, this solution has several disadvantages, so go through them as well before opting for this.

Step-1. First of all, users need to set their database in a single-user mode. For that they can use the below command:


Step-2. Run the DBCC CHECKDB command on the server.

(Video) part ONE how to fix damaged or corrupted mdf file in sql server

DBCC CHECKDB ('database_name')

Step-3. Verify the Index ID based on these two scenarios:

  • Index ID greater than 1 – Drop it & create it again.
  • Index ID is 0 or 1 – run the command again to repair MDF file easily.

Step-4. Select the Repair type from the following commands:


This command is basically meant to repair the database in detail but there is a high risk of data loss. That is because it deletes the entire damaged section in spite of repairing it. Thus, it is risky to opt for this solution.


The repair rebuild is the solution for users who try to repair the entire database files without any data loss. However, this is the exact reason why this command is slow like a snail. It takes quite a long to & does not guarantee 100% results to repair SQL MDF file safely.

DBCC CHECKDB ('database_name', REPAIR_FAST);

Last but not least, the repair fast command is to quickly repair the damaged MDF file. It is only meant to repair the files that are not highly corrupted. This can only fix small corruption issues but very fast.

Step-5. Set the database in Multi-user mode.


Drawbacks of the Manual Solution – Why DBCC CHECKDB Is Not Ideal

The manual solution comes with several drawbacks that users need to be aware of. Make sure to know these shortcomings before adopting this method to get the database files back in a healthy state.

  • The manual solution is quite complex & involves multiple steps that are enough for users to make any mistakes in the process.
  • New users won’t be able to execute the entire manual solution as they are not technically proficient in the commands.
  • The DBCC solution does not guarantee any results which means users can fail to repair MDF file in the SQL Server.
  • When it comes to the estimated time, the manual solution can take longer durations to repair the files. This also depends on the file size & the repair type command.

How to Repair SQL MDF File Using An Advanced Tool

In order to counter the drawbacks of the manual method & execute the entire damaged MDF repair task safely, an automated solution is reliable. SysTools SQL Recovery Tool is the most refined solution for users to easily repair MDF file in SQL Server.

Download Now Purchase Now

After downloading the tool, simply follow the below steps & repair your data without any error within the deadline.

Step-1. Launch the Automated Tool in your system & activate the license.

(Video) Repair Corrupt MDF and NDF SQL Database Files

Repair MDF File in SQL with Best How to Tutorial (2)

Step-2. Click on the Open button & then Add the damaged MDF files.

Repair MDF File in SQL with Best How to Tutorial (3)

Step-3. Set the Quick or Advance Scan mode to repair SQL MDF file.

Repair MDF File in SQL with Best How to Tutorial (4)

Step-4. Enter Destination database & Server to export healthy files.

Repair MDF File in SQL with Best How to Tutorial (5)

Step-5. Hit the Export button for damaged MDF repair & export.

Repair MDF File in SQL with Best How to Tutorial (6)

Modern Tool Features to Repair Corrupted MDF File

We just saw how easy it is to fix damaged or corrupted MDF files with this tool. It’s time for us to explore the features of this tool in depth.

  • Easily repairs MDF & NDF files with high-level corruption in them.
  • It is possible to repair & recover the deleted records in the SQL table.
  • Repairs tables, triggers, stored procedures, rules, functions, views, etc.
  • Export MDFs to a new or existing database in SQL after repairing them.
  • Export the MDF file to SQL Server, CSV file, or SQL-compatible scripts.
  • Possess various advanced features like date filter, generating reports, etc.
  • Supports SQL Server 2022, 2019, 2017, 2016, 2014, 2012, 2008, 2008 R2, 20058, & 2000 versions.

Also Read: SQL Server Error 3414 Solution in Easy Steps

(Video) How to repair corrupted MDF File?

Tool Specs & System Requirements

Before we proceed further, it’s quite crucial for us to understand the system requirements for this tool. In addition, the tool specs are equally important for users to understand.

Software Specification:

  • .exe File Size – 7.01 MB
  • Latest Version – 13.2

System Requirements:

  • RAM – 4GB
  • Disk Space – 100GB
  • Processor/CPU – 1GHz Minimum (2.4 GHz Recommended)

Trial Version Restrictions:

The software’s trial version only allows users to learn how to repair SQL MDF file for just 25 records from each table or 5 other objects as well.


  • Microsoft .NET Framework 5.0 or above than that.
  • Run Tool as an administrator.

Also Read: Fix SQL Server Error 945 without Hassles

Best Tips to Counter All Errors in the Repair Task

Now, we are all aware of the possible solutions, as well as their advantages & shortcomings for damaged MDF repair tasks. Before we conclude this article, knowing some tips & tricks to eliminate all the errors can be helpful.

Below are some of the tips for users to get rid of all the issues & errors while repairing their SQL MDF files.

  • Keep track of your MDF file & its storage location to make sure it’s healthy.
  • Diverse tools in use for storing & accessing data files is one major key point.
  • Make sure you create the NDF files to back up your database in emergencies.
  • Disable the data transfer parameters while you repair SQL MDF file in your system.
  • Try to avoid the Non-Unicode data type. However, go for the Uni-code type for sure.
  • Make it a habit to store the data in a binary file type in order to avoid any errors later.

In A Nutshell

Finally, now, users can easily repair MDF file without any hassles using the mentioned stated above. Both manual and automated solutions work fine but there’s a massive difference between these two. For 100% guaranteed error-free results, the SysTools automated solution is what users need. It just makes the entire process smooth & eliminates the risks present in the automated solution.


How to repair corrupt MDF file in SQL Server? ›

Repair Corrupt MDF File in 5 Steps
  1. Launch SQL Recovery Utility in System.
  2. Click the Open button to Add MDF files.
  3. Now Select Quick or Advance Scan Mode.
  4. Set the Destination SQL Server Database.
  5. Hit the Export Button to Get Final Results.
Apr 3, 2023

How to restore MDF file in SQL? ›

Method 1. Using SQL Server Management Studio
  1. Open SSMS and go to "Object Explorer".
  2. Right-click the database you need to restore and select "Attach". Click the "Add" button when "Attach Database" Windows appears.
  3. Browse the location of MDF file and select it. Then, click "OK".
Feb 22, 2023

How to clear MDF file in SQL Server? ›

Using SQL Server Management Studio

Expand Databases, right-click the database from which to delete the file, and then click Properties. Select the Files page. In the Database files grid, select the file to delete and then click Remove. Click OK.

How do I recover a corrupted SQL file? ›

How To Repair a Corrupted SQL Database
  1. Step 1 – Attempt Repair with SQL Server Management Studio (Optional) ...
  2. Step 2 – Choose a Good Database Repair Tool (Recommended) ...
  3. Step 3 – Download Your SQL Repair Tool. ...
  4. Step 4 – Run Your SQL Database Repair Tool. ...
  5. Step 5 – Scan the Corrupted SQL Database.

What is the SQL MDF file repair tool? ›

EaseUS SQL Recovery is a professional MS SQL repair tool that allows you to repair MDF/NDF files and all corrupted SQL server database components. Generally, SQL database failure is due to the corruption of its primary data file, the MDF file, or its secondary data file, the NDF file.

How do I fix a corrupt master database in SQL Server? ›

Launch the SQL Server in single user mode and follow the steps below for recovering SQL server from a backup file. Now, On the SQL Server Properties Window, select the Advanced tab. Now, Go to the startup parameters tab and prefix '-m' in the startup parameters text box. Remove the prefix after the process is complete.

How to restore MDF file without LDF? ›

Attach MDF File Without LDF file by using T-SQL script: You can also run a TSQL Script on SQL Query to restore MDF database in SQL Server and recreate your transaction log file. Where, testdb is the name of your database. Now you can check your database in the database folder.

How to shrink MDF file in SQL Server by query? ›

How to Shrink . mdf File in SQL Server
  1. Connect to the SQL Server Management Studio, Go to Databases.
  2. Select the desired database that needs to be shrunk.
  3. Right-click on the database, Select Tasks >> Shrink >> Files.
  4. Make sure that you choose Data File type for shrinking MDF File.
  5. The options of Shrink Option are as follows:
Mar 1, 2023

Can we restore database with only .MDF file? ›

Note: SQL Server uses an MDF file to restore data from a database and a transaction log file to restore the database logs. However, if you don?t have a log file, you can use the primary data file alone to perform the restore process.

What is the best practice to purge data in SQL Server? ›

To do a fast data purge we will utilize a little used feature in SQL Server, Partition Switching. Every table in SQL Server has at least 1 partition. In SQL Server you can quickly move an entire table from one table to another using the Alter Table Switch command. This leaves the original table fully intact, but empty.

How to restore MDF and LDF files in SQL Server 2016? ›

Using Enterprise Manager
  1. Expand the registered SQL server.
  2. Right-click Databases, select All Tasks -> Attach Database…
  3. Click the “…” button to browse for the . mdf file.
  4. Highlight the necessary . mdf file and click OK.
  5. Click OK again.

How do I manually DELETE MDF and LDF files? ›

Manually delete mdf and ldf files. Right click on database in SSMS and click 'Delete'.

How do I manually fix corrupted files? ›

How to Fix Corrupted Files
  1. Perform a check disk on the hard drive. Running this tool scans the hard drive and attempts to recover bad sectors. ...
  2. Use the CHKDSK command. This is the command version of the tool we looked at above. ...
  3. Use the SFC /scannow command. ...
  4. Change the file format. ...
  5. Use file repair software.
Feb 25, 2022

What is the command for fixing corrupt files? ›

In the command prompt window, type SFC /scannow and press Enter . System file checker utility checks the integrity of Windows system files and repairs them if required.

What command cleans corrupted files? ›

The sfc /scannow command will scan all protected system files, and replace corrupted files with a cached copy that is located in a compressed folder at %WinDir%\System32\dllcache. The %WinDir% placeholder represents the Windows operating system folder. For example, C:\Windows.

What is the best MySQL repair software? ›

Aryson MySQL Database recovery tool is one of the best and easiest tools to repair corrupted or missing SQL files. Aryson has expertise in repairing MySQL databases from both InnoDB and MyISAM tables. Aryson offers easy and fast conversion to its users.

What is the MDF file in SQL? ›

mdf file stands for Master Database File and is a SQL database packaged into a file. These files have an associated . ldf (Log Database File) that contains the logs for that database. You can create new databases that are stored in . mdf files by adding a Service-based Database item to your project.

How do I view a SQL MDF file? ›

Method 1: Open MDF File Using SQL Server Management Studio (SSMS)
  1. Launch SQL Server Management Studio (SSMS) and Connect to the SQL Server Instance.
  2. Here, you can view the SQL Server Instance.
  3. In the Object Explorer, right-click on the Databases and then click on Attach.
  4. Now an Attach Databases window is opened.
Apr 28, 2023

How to rebuild master database in SQL Server using CMD? ›

Use the SQL Backup Pro command line interface ( SQLBackupC.exe ) to restore the master database. For example, at the command prompt, type: SQLBackupC.exe -SQL "RESTORE DATABASE master FROM DISK = 'C:\Backups\master 20070101. sqb'"

How to rebuild master database in SQL Server without backup? ›

How to Restore Master Database in SQL Server Without Backup
  1. Launch SQL Server Configuration Manager.
  2. Choose the SQL Server Services option to check the currently running services.
  3. Select a running service and right-click on it. ...
  4. Repeat the process for all running services that you want to stop.
May 19, 2022

How do I repair SQL Server? ›

Launch the SQL Server Setup program (setup.exe) from SQL Server installation media. After prerequisites and system verification, the Setup program will display the SQL Server Installation Center page. Click Maintenance in the left-hand navigation area, and then click Repair to start the repair operation.

What is the difference between MDF and LDF file? ›

MDF file is the primary data file of a SQL database. The . LDF file is the transaction log file of a SQL database. The transaction log is used to guarantee the data integrity of the database and for data recovery.

How to convert MDF and LDF to bak? ›

2 Answers
  1. right-click on 'user databases', 'attach' then select your MDF file.
  2. right-click on the attached database and 'tasks', 'back up'; use 'remove' and 'add' in the destination box if you want to change the filename.
Apr 25, 2012

How do I find MDF and LDF files? ›

The mdf and ldf can be set for each Microsoft SQL database, by right-clicking on the database, in Microsoft SQL Server Management Studio and selecting Properties. In the Database Properties Select Files. In this window, the current settings for the mdf and ldf are displayed.

How to open MDF file in SQL Server without LDF? ›

Ways To Attach MDF Without LDF File
  1. Launch the Microsoft SQL Server Management Studio. Right-click on the SQL Server directory node and select New Query option from the list.
  2. The SQL query box will get open. Use this T-SQL script to attach MDF without LDF file in SQL Server.
  3. The output results would be shown like this.
Jan 16, 2020

Can we split MDF file in SQL Server? ›

It is not possible to split a large database . mdf from one single file to multiple .

How do I rebuild all indexes in SQL Server? ›

SQL Server Management Studio
  1. In Object Explorer, Expand the database that contains the table on which you want to reorganize an index.
  2. Expand the Tables folder.
  3. Expand the table on which you want to reorganize an index.
  4. Expand the Indexes folder.
  5. Right-click the index you want to reorganize and select Rebuild.

Can a database have multiple MDF files? ›

While it is not recommended in the best practices, it is totally possible to have a single database with two MDF files. Here is how you can do it. The script above will create a database with two MDF files and it will work just fine.

How to restore database without backup? ›

Manual Methods to Recover SQL Database without Backup
  1. DBCC CHECKDB (DATABASE_NAME): Check the entire database for repair in command line or query.
  2. REPAIR_ALLOW_DATA_LOSS: Repair data by allocating and deallocating rows. ...
  3. REPAIR_FAST: Repair the data in a fast process, but it makes only minor changes.
Feb 22, 2023

How do I restore my full database? ›

A. Restore a full database backup
  1. In Object Explorer, connect to an instance of the SQL Server Database Engine and then expand that instance.
  2. Right-click Databases and select Restore Database...
  3. On the General page, use the Source section to specify the source and location of the backup sets to restore.
Mar 3, 2023

How to clean dirty data in SQL? ›

How do you clean data in SQL?
  1. Remove irrelevant data. What's considered irrelevant data will vary based on the dataset. ...
  2. Remove duplicate data. ...
  3. Fix structural errors. ...
  4. Do type Conversions. ...
  5. Handle missing data. ...
  6. Deal with outliers. ...
  7. Standardize/Normalize data. ...
  8. Validate data.
Mar 19, 2023

Which is the fastest way to purge data from a table? ›

By far, the fastest way to delete a bunch of records is to use the TRUNCATE TABLE statement. This is much faster than the DELETE statement because it does not log any of the row-level delete operations. However, you can only use TRUNCATE TABLE : To delete ALL the records in the table.

How to clean buffer in SQL Server? ›

To clear SQL Server's cache, run DBCC DROPCLEANBUFFERS , which clears all data from the cache. Then run DBCC FREEPROCCACHE , which clears the stored procedure cache.

How to access MDF file without installing SQL Server? ›

Open and View MDF File in 5 Steps
  1. Launch Software in your Windows system.
  2. Click on Open button & add MDF data files.
  3. Select the Quick or Advanced Scan option.
  4. Enable Preview Deleted Records checkbox.
  5. Now view all your data files after completion.
Apr 7, 2023

How to restore database in SQL Server? ›

Log in to the computer on which you want to restore the database. Open Microsoft SQL Server Management Studio. In the left navigation bar, right-click on Databases and then click Restore Database.

Where is the MDF file located? ›

mdf file from default in c:\users\username - Microsoft Q&A.

What happens if I delete LDF files? ›

You can't delete the ldf as long as SQL server is running. If you stop SQL Server and delete the ldf, then you will get into below state: "Recovery pending". This means that recovery failed and it is time to perform a restore.

How do I change the location of MDF and LDF in SQL Server? ›

Change the file locations with an ALTER DATABASE command:

USE master; --do this all from the master ALTER DATABASE foo MODIFY FILE (name='DB_Data1',filename='X:\NewDBFile\DB_Data1. mdf'); --Filename is new location ALTER DATABASE foo MODIFY FILE (name='DB_Data1_log',filename='X:\NewDBFile\DB_Data1_log. ldf');

Can you delete .MDF file? ›

It would not be okay to delete just the MDF file but you could drop the database which would delete the files. You are then committed to performing the restore as your only course of action.

How do I fix a corrupt master file table? ›

How to Fix Corrupt Master File Table Error
  1. Step 1: Stop Using the Drive. To avoid permanent data loss, do not attempt any further fix via Disk Management or any third-party partition manager tool after you see the CHKDSK error.
  2. Step 2: Use Error Checking Tool. ...
  3. Step 3: Restore Data. ...
  4. Step 3: Format the Drive.

How to encrypt MDF file in SQL Server? ›

mdf> file and go to Properties > General > Advanced Attributes. Select the Encrypt contents to secure data check box and click OK. Note: If the folder is not encrypted yet, select Apply changes to this folder, subfolders and files when prompted.

How to connect MDF file in SQL Server? ›

Run SQL Server management studio as an administrator and attach the database. Explicitly grant full control access to the MDF file and LDF file of the database. To do that, Right-click the database files Select the security tab select the appropriate user and grant full control to the user.

How to fix MBR with command prompt? ›

Fix the MBR in Windows 10
  1. Boot from the original installation DVD (or the recovery USB)
  2. At the Welcome screen, click Repair your computer.
  3. Choose Troubleshoot.
  4. Choose Command Prompt.
  5. When the Command Prompt loads, type the following commands: bootrec /FixMbr bootrec /FixBoot bootrec /ScanOs bootrec /RebuildBcd.

How do I make a corrupt file uncorrupt? ›

The Open and Repair command might be able to recover your file. Click File > Open > Browse and then go to the location or folder where the document (Word), workbook (Excel), or presentation (PowerPoint) is stored. Don't try to open the file from the Recent section as this won't go into the Open dialog box.

How do I attach an MDF file to an existing database? ›

To attach the database, right click on Databases and select Attach... on the SQL Server instance where you want to attach the database. The following screen opens. Click on the Add button to find the mdf file that you want to attach, select the file and click OK.

Where are SQL MDF files stored? ›

Default Location of MDF File in SQL Server. Files that are common and used by all instances on a single system are installed inside the folder :\Program Files\Microsoft SQL Server\nnn\.

How to restore MDF file in SQL Server 2005? ›

Using Enterprise Manager
  1. Expand the registered SQL server.
  2. Right-click Databases, select All Tasks -> Attach Database…
  3. Click the “…” button to browse for the . mdf file.
  4. Highlight the necessary . mdf file and click OK.
  5. Click OK again.

How do I find the SQL Server version of an MDF file? ›

the version of the MDF will be the DWORD value at offset 0×12064 in the file. Save this answer. Show activity on this post. Files are not versiones by express or not - only by file version / sql server version.


1. How to open an .MDF file? (Attach a Database in SQL Server)
2. Repairing a Corrupt MDF File with Stellar Phoenix SQL Database Repair
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3. Repair MDF File After DBCC CHECKDB Failed | SQL Recovery
4. Want To Repair MDF and NDF Files Easily
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5. How to repair corrupt SQL Database MDF File with SysInfo SQL Database Recovery software
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6. Restoring SQL Server database using just the MDF file
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