DBCC CHECKDB Command in SQL Server: Repair SQL Database

Summary: In this technical era, databases play an important role in managing large data volumes. Whether you use MS SQL, MySQL, or any other DB, they all have one motto. It is to keep data organised and maintain its integrity to ease the task of DBAs. Here, we will explore the DBCC CHECKDB command, i.e., a powerful MS SQL utility and a DatabaseFileRecovery SQL Database Recovery Tool. It is optimal for diagnosing and repairing database files. Download Now Purchase Now

About SQL Server DBCC CHECKDB

DBCC CHECKDB, short for Database Console Command Check Database, is a native feature to check the SQL database health. It verifies that all database objects’ logical and physical integrity are consistent and that no disruptions occur. There are several purposes that this command in SQL Server serves as follows:

• Identifies corruption in database tables, indices, and allocation structures.
• It upholds the logical connections of the database system tables.
• It suggests ways to fix and recover any detected issues or inconsistencies.
• Keeps the MS SQL database’s condition and responsiveness stabilised.
• To avoid SQL Server downtime, operational and other costs, and data losses.

When Users Must Run DBCC CHECKDB Command?

After learning its benefits, one must understand at what point exactly it is useful. Some common scenarios where DBCC CHECKDB is best to implement are:

• For long data stability and to avoid corruption, use it in regular maintenance operations. 
• Use it after facing an unexpected or abrupt system shutdown and power failure.
• When you encounter SQL Server Error 601 NOLOCK or other unexplained query errors, missing data, and failed backups.
• After restoring backup or large data and schema imports in the SQL database.
• While you move the database to another SQL Server, make changes, or face hardware failures.

Now, let’s proceed to find out how the command functions and help repair SQL database.

Implement DBCC CHECKDB Command in SQL Server

The DBCC CHECKDB is a free manual solution to recover SQL database after any error or corruption. Its syntax is DBCC CHECKDB (“Name of Your DB”); for a comprehensive database integrity check. 

Following this, you get two options to implement the command for handling the structural issues of the database. These are:

• Repair_Rebuild: It is a non-destructive repair option that fixes minor issues of the database and does not result in losses.
  • Syntax: DBCC CHECKDB (“Name of Your DB”, REPAIR_REBUILD);

• Repair_Allow_Data_Loss: It is a destructive solution that aims to eliminate all errors, even if the loss happens. You should only prefer using it as the last option and after taking a backup. Ultimately, it is suggested to avoid the method to protect data.
  • Syntax: DBCC CHECKDB (“Name of Your DB”, REPAIR_ALLOW_DATA_LOSS);

Manual Steps to Execute SQL Server DBCC CHECKDB Command

Run the below-given transact queries in your SQL Server Management Studio:

1. You need to first place the SQL Database into Emergency by the command:

ALTER DATABASE [Name] SET EMERGENCY;

2. Next, find the errors and inconsistencies with the following command:

DBCC CHECKDB (Name)

3. Further, put your SQL database in one-user mode with the command:

ALTER DATABASE [Name] SET SINGLE_USER

4. Now, the most important step is to run DBCC CHECKDB to repair the database:

DBCC CHECKDB (“Name”, “Action”)

GO

(Replace Action with Repair_Rebuild/Repair_Fast/Repair_Allow_Data_Loss)

5. In the end, set back the SQL database to all users by the command:

ALTER DATABASE [Name] SET MULTI_USER

Shortfalls of the Command DBCC CHECKDB

• Deallocates database rows and pages that may result in unrecoverable data.
• Leaves the database in a logically inconsistent state without a recovery guarantee.
• Requires repetition of steps many times to remove all the errors in the SQL database.

Substitution of the DBCC CHECKDB Command in SQL Server

If the DBCC CHECK command doesn’t work, how can you recover the database? How can a user ensure that the SQL database can be repaired? For this, SQL Database Recovery Software is a complete solution that equips users to resolve SQL databases’ structural damage and inaccessibility. It has specialised features and restores all database components with recovery modes. Additionally, the tool serves both MDF and NDF files to recover without loss. Moreover, it allows you to fix the database back to its original state in minimal time on all Windows OS. Besides that, its other benefits are that it provides a preview, saves data as scripts, and allows filtering data.

Instructions to Leverage the Dedicated Tool

1. Run software >> press Open >> add MDF.
2. Then, choose recovery mode (Standard/Advanced) >> click OK.
3. Afterward, expand hierarchy >> preview data >> choose folders.
4. Further, click Save SQL Data >> finalise Database or Script destination.
5. At last, refine data through filters >> hit OK.

Conclusion 

To summarise, the DBCC CHECKDB command is essential for any user working on SQL Server. It maintains integrity as well as provides repair options to keep the database good. In this blog, we outlined the command and how it functions. Furthermore, we learnt about a professional replacement if DBCC fails to repair the database. Moreover, it also has a demo version for testing and analysing the tool beforehand for free.

Frequently Asked Questions

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