Your database is very important for you as it stores all your important records. Instances may occur when you fail to access them, or they become corrupt. Sometimes, you may get an error message indicating database corruption in SQL Server. This can occur due to several reasons like server crash, any hardware or software issue, virus or malware attack, etc. Whatever is the reason for such corruption in SQL servers, it is very important to fix them. Otherwise, you can no longer access your database. Here, in this article, we have mentioned how to repair System database corruption in SQL Server along with some probable causes of the issue.
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What Causes Database Corruption in SQL Server?
There are several reasons why the Microsoft SQL database gets corrupted. In most cases, SQL Server database corruption occurs due to issues at the Input/Output subsystem level. This includes the failure or misbehaving of drivers, drives, and controllers. Before using any SQL database repair tool to repair your DB files, it is important to find the exact cause of the issue. Some other causes of this issue are given below:
- SQL Server database is misbehaving because of any bug in itself.
- Virus Injection or any Malware.
- Updating MS SQL Server to its latest version may also cause database corruption.
- Problems while attaching/detaching SQL MDF file.
- Outdated software or hardware in your system.
How to Repair Database Corruption in MS SQL Server?
Whenever corruption occurs in the SQL Server database, you should perform some simple methods and steps to cure such situations. There are several methods that a system administrator can use to repair or fix master database corruption. Some popular SQL repairing methods are:
Method 01: Restart the SQL Server
Restarting the SQL server can easily fix system database corruption issue in it. For this, you have to apply the following steps:
- Open a terminal in your computer and enter the following command to stop the SQL Server:
- systemctl mysql stop
- Type the following command to check the status of the SQL Server and press Enter:
- status mysql.service
- Once you are done with both the above commands, you can restart the SQL Server by the following command:
- restart mysql.service
Method 02: Use Microsoft SQL Server Management Studio Express
Microsoft has its own Management platform for SQL Server Administration. It helps users in recovering a corrupt master database file. You need Microsoft Web Platform installed on your system in order to use this management tool. After that, install the MS SQL Management Studio Express as per the latest SQL Server version. After that, all you have to do is:
- Step 1: Go to the following path: C:/Program files/Microsoft SQL Server / SQL Server Management Studio Express. This will launch the Management Studio Express on your device.
- Step 2: Now, enter the Windows Authentication login credentials, like your username and password.
- Step 3: Expand databases and then locate and right-click on the wt_shed file. Go to Properties >> Options.
- Step 4: Scroll to the bottom of the page and change Restrict Access to SINGLE_USER.
- Step 5: Tap the OK button and repeat step#2 for the wtMaster part of the database.
- Step 6: Now, select New Query from the toolbar and then copy and paste the following commands in the query pane.
- dbcc checkdb(‘wtMaster’,REPAIR_REBUILD)
- dbcc checkdb(‘wt_sched’,REPAIR_REBUILD)
- Step 7: Now, select Execute to start the SQL Server repairing process.
- Step 8: At last, follow steps 4 and 5 and revert the changes from SINGLE_USER to MULTIPLE_USER.
Method 03: Run DBCC CHECKDB REPAIR_REBUILD
Repair_REBUILD is the most secure manual method to repair your corrupted database. Well, this can help you only if the corruption level is not so high. You need to run “DBCC CHECKDB with Repair_REBUILD” as the following command:
DBCC CHECKDB (‘Database_name’, REPAIR_REBUILD);
Method 04: Run DBCC CHECKDB REPAIR_ALLOW_DATA_LOSS
The above method can help you only if there is minor corruption in a SQL database. In case of severely corrupted database, you can use ‘REPAIR_ALLOW_DATA_LOSS’. This command detects the corrupted part of the selected database file and then completely removes it. It must be noted that the REPAIR_ALLOW_DATA_LOSS command is not recommended to perform as it causes huge data loss.
Method 05: Use Third-Party Tool
If the above manual solutions fail to recover your SQL files, you can use the SQL database repair tool. There are several SQL repair software available in the market, but we recommend using Stellar Repair for MS SQL. It is the best tool to restore SQL database with minimal downtime. The software repairs corrupt SQL database (MDF and NDF) files and restore all the objects.
Some Amazing Features of Stellar Repair for MS SQL
Given below are some amazing features of this Stellar product that makes it unique and different from others:
- The software uses robust scanning algorithms to recover data from damaged or corrupt MDF and NDF files.
- You can easily recover all the database objects, including Tables, Keys, Indexes, Stored Procedures, Views, Triggers, Rules, User Defined Functions, etc.
- Stellar SQL repair tool fixes the corrupt SQL database without affecting the existing table data and original hierarchy.
- The SQL Server recovery software scans the corrupt databases and allows you to preview all recoverable items in a tree-like structure.
Tips to Avoid SQL Database Corruption
Given below are some important tips that you should never do if you have problems with the SQL database corruption:
- Never reboot the SQL server
- Do not shutdown SQL Server
- Always keep a proper backup before upgrading SQL Server
- Do not connect/re-connect database
Conclusion:
SQL Server crash is one of the common issues that can bother you while accessing the database files on your device. It is not possible to know whether a database has turned corrupt or not until it becomes inaccessible. Fortunately, you can apply the methods discussed in this blog to fix system database corruption in SQL Server. Some third-party SQL database repair software like Stellar Repair for MS SQL can help you to restore your database and all its data. You can restore all the files with integrity and precision. Must give it a try!
