How to Fix Page Level Corruption in SQL Server Instantly

SQL Server users face different challenges when working on the SQL Server database. Page level corruption in SQL Server is one of the horrifying situations for any administrator as this will harm the data stored on the server. As a result, it is no longer possible to fetch the data. If you suffer from such circumstances, act immediately to fix SQL Database page level corruption. In this post, we will discuss various reasons with their respective solutions to resolve this corruption from SQL Server database.

How Does Page Level Corruption Occur?

Before knowing the reasons, let’s explore how this corruption occurs. Basically, SQL Server stores all the data in the primary file, i.e., MDF(Master Data File). Each MDF file contains the primary information in pages. Now, these pages are divided into header, body, and slot array. If any information from the pages is changed randomly, a user won’t be able to open the page from the file.

Whenever such issues occur, the first reaction of users is to simply restore their SQL databases. However, it is not only wrong but also should be avoided at first. Now, if you are thinking about what we should do at first, then here’s the answer:

1. The first step is to put the database in SINGLE_USER mode to avoid interference during the repair process. 
2. Next, take a backup of all the uncommitted transactions till the point of page corruption. 
3. Then, use a healthy backup till before the page corruption occurred, and use the same for a clean restoration. 
4. Once this is done, add the transaction logs one by one. 
5. Next, restore the tail log, which was done in the second step. This will help to restore the data up to the point of corruption in SQL database pages. 
6. After the database has been restored, run the DBCC CHECKDB command to ensure there is no corruption in the database. 
7. Once it is verified, set the database back to multi-user mode.

Know the Critical Reasons of this Issue

• Hardware Failure: Any malfunction in the electronic circuits of the hard drive or other components can lead to corruption.
• Virus Intrusion: Ensure to thoroughly scan the setup files while downloading any software to the SQL server.
• Sudden Power Failure: If the power supply is interrupted while the database is running, this can lead to SQL Database page level corruption.
• Improper Update Installation: It is a smart practice to avoid installing unnecessary updates, as this will keep the SQL database in a healthy state.
• Unidentified Error: There are times when the server catches corruption due to its own issues. There’s no thumb rule that all issues will be identified, as there are some unidentified errors.
• SQL Server Bugs or Patch Issue: Another reason for this corruption can be bugs in the SQL Server or due to SQL Server patches and updates.  

Note: With any of these reasons, if you find glitches in the server, try to backup your data immediately. As you never know how page level corruption can trouble and harm your crucial data!

Symptoms of Page Level Corruption in SQL Server

Here are the common symptoms that a user might come across when a page-level corruption occurs in the database. 

• When a page is corrupted in the SQL Server database, error codes like SQL Server error 823 occur. 
• The next common symptom encountered is the backup failure in the database.
• With the corruption in the SQL Server page, the database becomes inaccessible in most cases. 
• In major cases, when the server encounters corruption, it can further lead to the SQL Server process terminating unexpectedly.

By looking for these symptoms in the articles, a user can get the general idea that there is a corruption in the SQL Server database files. We will now take a look at the methods that will help to repair and fix the page level corruption in the database.

Also Read: How to fix cyclic redundancy check error 23 in SQL Server easily?

Manual Technique to Fix Page Level Corruption in SQL Server

Before implementing the steps, it is advised to take a backup of your MDF and LDF files. This guide will help you find the reference point from which you can recover the database. Also, it is suggested to download the text comparison and data comparison tool. This will make the process easy by comparing the corrupted data and the original data.

Steps to repair SQL Database page level corruption manually are as follows;

• Initially, check the differences between the original file and the corrupted file using text comparison tool
• Now, run the DBCC CHECKDB command on the corrupted file. As this will ensure to check the database file, identify the defects and advise the minimum requirement of data fixing.
• Run the DBCC PAGE command to analyze the infected page content after switching on the trace flag 3604 first

DBCC TRACEON (3604)

DBCC PAGE ({ ‘dbname’ | dbid}, filenum, pagenum [, printopt={0|1|2|3}])

In the above command, filenum and pagenum are page IDs that are related to system tables. The other parameters 0,1,2, and 3 define the following,

• 0 – This will print the header part of the page
• 1 – It is the page header with per row hex dumps
• 2 – It is the page header with a detailed page hex dump
• 3 – This is a page header with an elaborated per-row interpretation

Now, verify the page number and the physical offset. To perform a logical consistency error and read the table using the command below,

SELECT * from dbo.tablename

After navigating the location where the corruption has occurred. Make use of the text comparison software to compare it with the original page.
After detecting the errors, run the DBCC CHECKDB command on the recovered file to fix the page level corruption in SQL Server

What are the Possible Challenges Faced in the Manual Method?

• Need to invest a dedicated time and requires enough technical expertise to resolve SQL Database page level corruption.
• Fault-prone is a direct editing of the file, where checksums are examined on every page. If the copy/paste is not done properly, input/output errors will occur. In which it becomes difficult to open the database.
• If multiple locations are corrupted, the other type of pages will also be infected, where the SQL server fails to open the file.
• While implementing the manual method, the risks of complete data loss are higher, making it difficult for users to trust this method. 
• When a page is corrupted in the SQL Server database, it is crucial to locate the exact page. In case the affected page is missing, the process of repair gets complex.
• To proceed with the method and repair process precisely, the users must be aware of the page structure in SQL Server.

Resolve SQL Database Page Level Corruption – Expert Approach

After reading and understanding the various consequences associated with the manual method, it is clear that it is a challenging approach. Moreover, it requires detailed knowledge of SQL Server for the implementation. Now, as we discussed earlier, it is important to choose the right way to repair the issue, as one wrong step can lead to permanent data loss. With the advanced solution, like the SQL Recovery Tool, any corruption in the SQL Server page can be repaired quickly. Furthermore, it can efficiently fix corrupted MDF and NDF SQL database pages while preserving the data integrity and without the risk of any data loss. Here are the steps to use the automated solution.

1. Install and run the recovery software. Click on the Open Button to add the database files.
2. Choose a scan mode from Quick Scan and Advance Scan. Once the scan is complete, preview the recovered files.
3. Next, click on the Export Tab to save the recovered files to a desired destination. In the Export options, add the authentication and login details to proceed.
4. Select the database objects to be recovered and click on Export button to repair page level corruption in SQL Server.

Concluding Words

When it comes to fix page level corruption in SQL Server, a majority of users fail to resolve it manually. Therefore, it is always the best option to use a professional approach. This will help to fix all kinds of corruptions from the database, including SQL Database page level corruption. So, if you have recently encounterd this issue, go through the article thoroughly and repair the issue in no time. 

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