How to Recover Data from Log File in SQL Server – Step by Step
With the help of this article, we are going to explain how to recover Data from Log File in SQL Server professionally without any hassles. To understand the scenario better, we will take a look at some of the common scenarios where it becomes crucial to restore data from a log file. Below is an example of what kind of challenge a user might encounter.
User Query:
We are using SQL Server 2012 standard edition. This morning, when I connected to my SQL Server database, it was running fine and completely accessible. But, somewhere around 2:14 pm, I started facing a problem in the database with the following error message. Therefore, I’m clueless about how to restore the database from the LDF file.
After consulting with my administrator, we found that there is a corruption in the .mdf file. Evidently, the worst thing is that, being my client database, I cannot afford to lose a single attribute of the database. Thus, I looked into the backup of the current database, but it was 13 days old. Can someone help me? How do I recover data from a log file in SQL Server?
As we read here, we came to know one of the situations where it is crucial to recover data from the SQL Server log file. Now, moving on, let’s take a look at some other common situations where users might need to restore data using an .ldf file.
Why Users Need to Recover Data from SQL Server Log File?
- In case of accidental data deletion, it is often considered to restore data from log files, as SQL Server transaction logs record the deleted data on the server.
- There are situations where the .mdf file of the database gets corrupted, and there are no recent backups of the specified database. In these scenarios, the .ldf files might help, as they store recent transactions or uncommitted changes that aren’t in the backup.
- When a transaction fails, it is nearly impossible to roll it back completely. The SQL Server .ldf files help, as they have complete transaction details.
- To understand and find out who made changes in the database and check who deleted data from SQL Server table, the log files help the database administrators find out who made what changes.
What’s the Professional Way to Recover Data from Log File in SQL Server?
Simply, having a healthy backup of a database is a relief to a SQL Server DBA. But what if the backup is not available or the backup is damaged too? Then, what do we do? Fortunately, there’s a way to retrieve data from a log file with the help of an advanced tool. Evidently, for this, SysTools SQL Log Analyzer Software is the best option.
It is an authentic way to potentially analyze the transaction log file and restore the data from it. In addition, one can easily recover deleted records in SQL Server from the LDF file. This tool provides flexibility to the user by retrieving the data directly into the Live SQL Server Environment or as a SQL Script. Moreover, it can restore data from the log file in Microsoft SQL Server 2025, 2022, 2019, 2017, 2016, and prior versions. Let’s check out how the tool works and view log file of SQL Server.
Phase 1: Restore Data from Transaction Log File in SQL
We are now going to perform the restoration of the database through the transaction log file. This can be done by following the steps mentioned below:
Step-1. Download, install, and launch the advanced solution on a Windows machine.
Step-2. Now, click on Open button from the top left corner to add the database files (.ldf & .mdf) into the software.
Step-3. A new window will appear with two different options to add the LDF file to the software:
- Online Option: If you are going with the online option to recover data from the Log File in SQL Server DB, then it will ask for the details like Server Name, Username & Password, and Database Name, to which you want to read.
- Offline Option: If you are going with this option, then the software will ask for .ldf and its associated .mdf file.
Evidently, in the above scenario, we have to choose the Offline option and add the .ldf and its associated .mdf to the software by clicking on the (…) button.
Step-4. Next, click on OK button to proceed with recover data from log file in SQL Server process.
Step 5. After clicking on OK, it will prompt for a message that “Could not identify SQL Server version for the selected .mdf/.ldf file. Please select appropriate version of SQL Server”. Just click on OK.
Step-6. Now, select the appropriate version of your SQL Server database files.
Step-7. After providing the accurate version of the corrupted .mdf file, the software will scan the .ldf file and display the transaction details (INSERT, UPDATE & DELETE) after scanning. Then, click on OK.
Step-8. Preview the transactions and their complete details in the software preview pane.
Step-9. To preview the transactional details of a specific table, select the desired table from the left panel to move ahead with the recover data from log file in SQL operation.
Phase 2: Export Recovered Data from SQL Transaction Log File
Step-10. Click on the respective checkbox of which table’s data you want to export, and then click on the Export button to save the data directly to SQL Server.
Step-12. Choose the desired transactions to be exported: (INSERT, UPDATE, DELETE).
Step-13. Apply Date Filter, if you want to retrieve the data from the log file of a specific time interval.
Step-14. Choose the Export as SQL Server Database if you want to save the recovered data directly to SQL Server.
For this, you need to provide Server details like Server name, Username & Password.
Step-15. Select the destination database option as Create New Database or Export to Existing Database. Finally, click on Export to finish the recover data from log file in SQL process.
When to Choose the Automated Solution?
The software comes with plenty of features as well. In most cases, these features reduce the users’ workload. We will now take a look at these advanced features to understand the optimal situations to use the solution.
- For Examining Log Files: If users want to audit, examine, and analyze the LDF files, they can opt for this solution. This software is purposely used by IT experts for such tasks daily.
- To Fix Missing Log Data: There are scenarios where users have deleted data or missing data from the Log files. Therefore, in such cases, users can simply restore database from LDF file with ease.
- For Corrupted Log Fix: This advanced utility is also a sure-shot method for users to fix damaged LDF files. There are multiple filters present here along with some customization options.
Apart from these, the tool is beneficial for users in many cases where the features are helpful. Some of these features for SQL Server recover from the LDF file are:
- Track Modifications by User
- Handles Schema & Data
- Multiple Export Options
- Export Selective Data
- Online & Offline Mode
- Auto-Locate MDF File
Final Thoughts!!
Through this technical guide, we have discussed how to recover data from log file in SQL. As we all know, disasters always come without any notice in the SQL database. Due to this, you can lose your sensitive data. Therefore, in this article, we have discussed a solution that recovers data from a log file in SQL Server without losing a single bit of data.
Frequently Asked Questions
Ans: The software can get data from the log file directly into the SQL Server environment & help users know how to retrieve data from log files in SQL Server.
Ans: It becomes cumbersome to recover data with a manual procedure. Hence, it is suggested to try the automated software solution.
Ans: Yes, it is very easy to recover a database from an SQL LDF file into a SQL Script with the advanced tool. Moreover, the software allows users to repair LDF file as well.
Q-4. Can we rebuild the log file in SQL using SSMS?
Ans: Yes, users can rebuild the SQL Log file using the SSMS (SQL Server Management Studio) through some steps. However, users must be technically proficient to execute the manual task.
Q-5. What is redo log in SQL?
Ans: We can say that a redo log is a disk-based data structure that is crucial for emergency recovery to fix data written by false transactions.
