Table Of Contents
- Consequences of a corrupted Database file
- Best ways to recover a corrupt SQL database
- Using Server Management Studio (Optional) to fix corrupted SQL server database
- 1. Set the Database to Emergency Mode
- 2. Analyze the database for errors
- 3. Repair the database
- Using SQL repair tool to repair database
- Which use cases necessitate the use of Stellar Repair for MS SQL?
Best Way To Recover A Corrupt SQL Database
Last Updated on: November 15th, 2024
The SQL server uses the Master Database File (MDF) format to store its data, with the file header page being the first page of this file. It includes details about various file attributes, such as database size, file signature, and so on.
While trying to link the MDF file, it often becomes damaged. This causes the users of SQL Server to encounter several header errors.
Consequences of a corrupted Database file
Any of these errors result in a mismatch of header information, making the database inaccessible to the users. All these signs indicate a corrupted database file. Unless you find ways to recover the SQL database, you cannot access the database.
At worst, a corrupt database can result in data inconsistency, loss of data, and operational inefficiencies. The need of the hour is therefore to solve the issue at the earliest and get back to work. Experts prefer to troubleshoot the problem themselves, but manual ways are often time-consuming.
Moreover, despite investing excess time, they may not get the desired result. In such cases, having data recovery software on your PC would do the needful. Stellar Repair for MS SQL is a widely embraced tool in this line.
Right here, we will discuss more about these manual ways to recover corrupt SQL databases. In addition to this, you will also get to know about using an SQL database repair software to get even with the corrupted SQL server database. Let?s begin.
Best ways to recover a corrupt SQL database
You may try to fix a problematic SQL database manually. Alternatively, using an SQL repair tool such as Stellar Repair for MS SQL can prove more effective.
Using Server Management Studio (Optional) to fix corrupted SQL server database
If the problem is minor, you can fix the corrupt database with the help of SQL Server Management Studio (SSMS). The basic steps to get away with any such minor corruption issue are as follows:
1. Set the Database to Emergency Mode
Putting the database in Emergency mode will allow the admin only read-only access to the database.
Here is how to do it.
- Open SQL Server Management Studio.
- In the Object Explorer, double-click Databases
- Right-click the database that has gone corrupted
- Click New Query.
- Run the query as shown below:
ALTER DATABASE [DBname] SET EMERGENCY.
e.g. ALTER DATABASE [SQL_DB_ATF] SET EMERGENCY;
2. Analyze the database for errors
Use the DBCC CHECKDB command to analyze the corrupted database and find out the errors. Here is the command syntax:
DBCC CHECKDB (DBname) WITH ALL_ERRORMSGS, NO_INFOMSGS
e.g., DBCC CHECKDB (SQL_DB_ATF) WITH ALL_ERRORMSGS, NO_INFOMSGS
3. Repair the database
You may try a few command options to fix your corrupted database and recover the data.
REPAIR_REBUILD: This command helps to repair missing rows or rebuild corrupt pages. You should use it to repair a database that has no possibility of data loss. The screenshot below shows how to run this command in SSMS.
e.g. DBCC CHECKDB (?SQL_DB_ATF?, REPAIR_REBUILD) WITH NO_INFOMSGS;
REPAIR_ALLOW_DATA_LOSS: This command can repair your database. But during the process, it may delete several pages of the database. Therefore, run this command only if you cannot do without it.
Before proceeding with this repair command, you will have to put the DB in SINGLE_USER mode. This will ensure that no other user can change the data during the database restoration.
For this, run the below command:
USE master;
GO
ALTER DATABASE SQL_DB_ATF
SET SINGLE_USER
WITH ROLLBACK IMMEDIATE;
Here, the ROLLBACK IMMEDIATE option will roll back all the incomplete transactions and disconnect any connection with the database. The message shown below will confirm the same.
Nonqualified transactions are being rolled back. Estimated rollback completion: 0%.
Nonqualified transactions are being rolled back. Estimated rollback completion: 100%.
Set SINGLE_USER Mode using SSMS
Alternatively, you may also go for the option to set SINGLE_USER mode by using MS SQL Server Management Studio. Here are the steps for the same.
- Open the object explorer on the left pane of the SQL Server Studio home screen
- Find the corrupt database that you want to recover and double-click it.
- Click Properties ????Options ???? State (The last section on the right side of the window when you click Options)
- Look for Restrict Access and select the drop-down button corresponding to it.
- Select SINGLE_USER and click OK.
- This will switch your database to SINGLE_USER mode.
Now let?s move back to REPAIR_ALLOW_DATA_LOSS command. Run the following.
DBCC CHECKDB (‘SQL_DB_ATF’, REPAIR_ALLOW_DATA_LOSS) WITH NO_INFOMSGS;
If this command succeeds in the repair and recovery of your database, change the SINGLE_USER Mode to MULTI_USER.
Here are all the commands together.
USE master;
ALTER DATABASE [SQL_DB_ATF] SET SINGLE_USER WITH ROLLBACK IMMEDIATE;
GO
DBCC CHECKDB (SQL_DB_ATF) WITH ALL_ERRORMSGS, NO_INFOMSGS;
GO
DBCC CHECKDB (‘SQL_DB_ATF’, REPAIR_ALLOW_DATA_LOSS) WITH NO_INFOMSGS;
GO
ALTER DATABASE [SQL_DB_ATF] SET MULTI_USER;
GO
Using SQL repair tool to repair database
If all your ways to recover a corrupt SQL database fail and your data remains inaccessible, an SQL repair tool can help you out. Stellar Repair for MS SQL is the ultimate software to assist your cause in this context.
The tool is instrumental in repairing corrupt databases and restoring their components. In the process, it ensures to maintain the integrity of the database. It requires the least possible manual effort to reinstate database access through this software. Here are some of the prominent features that altogether make it the best way to recover a corrupt SQL database.
- Repairs Next Data File (NDF), a user-defined MS SQL Server secondary database file with .ndf extension
- Repairs Master Data File (MDF), which consists of the main information of the SQL Server database
- Repairs keys, tables, stored procedures tables, and all the other database components
- Recovers the SQL Server database that falls victim to Ransomware
- Allow you to delete records from the database
- Allows selective recovery of the database objects
- Shows the database objects that are possible to recover
- The Technician version of the SQL repair tool extracts the data from the corrupted backup file
Related: Data Lineage Simplified: Transforming Data Management For Better Operational Insights
Which use cases necessitate the use of Stellar Repair for MS SQL?
In several instances where SQL Server commands fail to recover the corrupted SQL server database, this SQL repair tool becomes beneficial.
- Your SQL Database goes into SUSPECT mode
- You want to recover your database from a corrupt or damaged backup file
- When the options associated with the DBCC CHECKDB Command do not deliver the expected results.
Stellar Repair for MS SQL is undoubtedly, one of the best ways to recover corrupt a SQL database.
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