How to Repair Corrupted SQL Server Database Using Effective Tactics
Are you looking for a way to fix SQL database that is corrupt or damaged? Do you want to repair damaged or corrupted SQL database with a simple and efficient technique? Then this write-up is for you. Here, users will learn multiple methods on how to recover data from corrupted SQL Server database. Before going to resolving workarounds, let’s see some real-life incidents faced by users and want a solution for how to repair SQL database MDF file.
“Help! My SQL Server database has encountered severe corruption. Though I have been using it for several years, I have never faced this type of corruption in my SQL database. I have tried some manual methods suggested by my friends but none of them was able to resolve this issue. I am afraid that all my database data will get lost forever. Please suggest me an effective way to repair corrupted database in SQL Server 2008.”
“Recently, there has been some instability in the power connection of our office. As a result, SQL database faced some damages. To retrieve data from the damaged database in SQL Server 2012, I have tried DBCC CHECKDB command, but it did not succeed to repair corrupted SQL database. Now, I am looking for a solution to this problem that will work for sure. Please share any such sure-shot solution through which I can fix database corruption in SQL Server.”
Let us understand what are the possible reasons that damaging or corrupting the database in Microsoft SQL Server environment.
The factors that cause corruption in SQL database is not restricted to a single one. Various reasons can contribute to the damage of the database and the users need to suffer. In this section, we will learn some of the main reasons:
- Power Cut: Abrupt power cut, sudden shutdown can be the reasons responsible for SQL corruption.
- Bugs: It is possible to have bugs in the SQL database. These bugs can also damage your database.
- File Corruption: Sometimes, a virus or malware can corrupt any file located within the SQL database.
- Hardware Problem: At times, hardware that helps to store and run the database can get damaged badly. In that case, the page level corruption takes place.
Read :- How to Repair SQL Database Page Level Corruption?
How to Fix or Repair Corrupt Microsoft SQL Server Database With Effective Manual Technique?
You can restore database from damaged MDF file in SQL Server with the help of versatile DBCC Check command. It is one and only solution that repair a corrupt database in Microsoft SQL Server effortlessly. Generally, there are two scenarios where you can use this method and fix SQL Server master database file. Let’s Begin!
Situation #1: Fix SQL Server Database in Recovery Pending Mode
The database undergoes Recovery Pending state when there is a resource-related issue arise during recovery procedure. In this scenario, the SQL Server database is not corrupted or damaged. However, due to some error in files or system resources makes it unavailable.
To fix Recovery Pending status in SQL Server, you need to detach the existing database and re-attach it again using T-SQL query. To get this method in detailed, go through this article once
Read :- How to bring database Online from Recovery Pending in SQL Server 2014 / 2016 / 2017
Situation #2: How to Repair SQL Server Database Marked as Suspect or Corrupted
In Suspect mode, it is possible that the primary filegroup might be damaged or corrupted. This reason makes SQL database unavailable. To repair Suspect database, you need to use DBCC Check command. Here, we described a general procedure that works to fix SQL Server database Suspect mode error proficiently. This process is classified into multiple steps. So, let’s begin!
Know More About SQL Server Suspect State, go through this write-up;
Reasons for Suspect Database in Microsoft SQL Server
Stage 1: Set SUSPECT Database to Emergency Mode
This mode exclusively allow system administrator read-only permission to the database. Plus, the EMERGENCY State can be set by the members of sysadmin only. To make database in EMERGENCY mode, run the following query on the panel.
ALTER DATABASE DATABASE_NAME SET EMERGENCY
Here, we take database_name – ‘testing’ and run the above-mentioned command.
Stage 2: Check Damage Level
You need to run DBCC CHECKDB (DB_Name) query and analyse the errors.
DBCC CHECKDB (Database_Name)
Stage 3: Execute Repair Command
With DBCC CHECKDB, there are three repair modes offered that can be used to bring back the database into functional mode from EMERGENCY mode:
It is capable to keep syntax for backward compatibility. It means you can run SQL Server 2005 database file in SQL Server 2008. No heavy repair actions are performed. If you want to resolve backward compatibility issue, then make sure database is in SINGLE USER mode instead of EMERGENCY Status.
To make database is in SINGLE_USER MODE, use the following methods:-
Method 1: Using GUI Approach
- 1. Select the database and right-click on it.
- 2. After that, click on Options as shown in the screenshot.
- Go to Restrict Access option and click on drop-down button. Then, select SINGLE_USER option and click on OK button.
Method 2: Using T-SQL Query
You can also change the database mode into SINGLE_USER, using T-SQL. For this, execute the below query in SSMS.
ALTER DATABASE DATABASE_NAME SET SINGLE_USER
USE REPAIR_FAST Command
After setting up the database to Single_USER Mode, execute the below query to repair database in SQL Server.
DBCC CHECKDB (N ‘Database_Name’, REPAIR_FAST) WITH ALL_ERRORMSGS, NO_INFOMSGS;
This repair command for SQL database is preferred because it has very less risk of data loss. Ideally, it performs all the repair procedures that REPAIR_FAST does. In addition, it performs some time-taking repairs too that including rebuilding the indexes. To use this, execute the below mentioned query.
Note: Make sure the database in in SINGLE_USER Mode.
DBCC CHECKDB (N ‘database name’, REPAIR_REBUILD) WITH ALL_ERRORMSGS, NO_INFOMSGS;
- REPAIR_ALLOW_DATA_LOSS :-
Along with repair, this performs the job of allocating and de-allocating the pages, delete the objects that are corrupt, and fix page errors. This also fixes the structural errors in the database. However, this type of repair always leads to some data loss. Moreover, it can run in EMERGENCY mode without any error.
DBCC CHECKDB (N’Database_Name’, REPAIR_ALLOW_DATA_LOSS) WITH ALL_ERRORMSGS, NO_INFOMSGS;
Stage 4: Set Database to MULTI_USER Mode
Once the database gets repaired successfully, use the following query and change the database mode into Multi user mode.
ALTER DATABASE DATABASE_NAME SET MULTI_USER
Unfortunately! DBCC CHECKDB Is Not An Ideal Solution
There are various scenario where DBCC CHECKDB Job fails to repair corrupt database in SQL Server 2000 / 2008 / 2008 R2 / 2012 and in other editions also. In that situation, you have to switch to other workarounds to fix SQL database to access the unavailable task.
To know More – Why DBCC CHECKDB Job Failed in SQL Server?
Efficient Method to Repair SQL Server Database Corruption
The above-mentioned approach does not guarantee the complete recovery of damaged database files. So to repair SQL Database, you must take help for third-party utility named as SQL Database Recovery Tool. This application can successfully repair both major and minor level of corruption in the SQL database MDF file. It can recover all database components of SQL Database including Rules, Functions, Tables, Triggers, etc.
What’s More – After repairing the MDF & NDF file, the tool can export the recovered database either to live SQL Server Environment or in SQL Script format. Adding to it, the tool can fix corrupt database of SQL Server 2017 / 2016 / 2014 / 2012 / 2008 / 2008 R2 / 2005 / 2000
Finally!! Get Best Solution to Repair Corrupt SQL Server Database
It is evident from above various factors give rise to corruption in Microsoft SQL Server. Due to which users need to fix corrupted SQL database to get back their tables, Views, Stored Procedures, functions, triggers, and other objects. If you are one of them, then you must consider implementing any of the techniques mentioned in this article. It could be the possibility that the manual technique i.e., DBCC CHECKDB get fails to repair SQL Server database marked as Suspect or Corrupted. For that case, you can go with the suggested tool discussed above.