Learning MSSQL Index Rebuild For Effective SQL Database Performance

For a database administrator, there is nothing more frustrating than a slow database performance. Several factors that impact overall database health, and SQL indexes are one of them. However, with the MSSQL index rebuild process, it is easier for the database administrators to improve the database health and resolve any issues caused due to the SQL Server indexes. 

So, without further delay, let’s take a look at how database health is impacted by SQL Indexes and how we can resolve them efficiently.

Are SQL Indexes Affecting Your Database Performance?

The database health is often impacted by the database objects. There can be several reasons for this, and one of them is index fragmentation. But what is it, and how is it affecting the overall database performance? Let’s now take a closer look at SQL Server Index Fragmentation and learn how MSSQL index rebuild is helpful in this situation. 

Index Fragmentation mainly occurs in the SQL Server database when the logical order of the SQL Server index pages does not match the physical order on the disk. Furthermore, due to this alignment issue, the server is unable to use the storage efficiently, which ultimately results in slower database performance.

When this index fragmentation occurs in the database, it impacts the database in several ways. Here are some of the issues created due to fragmented indexes in SQL:

• With the fragmented indexes, SQL Server has to perform additional I/O operations to read and fetch the data from the indexes, resulting in slower SQL query execution and, eventually, slower SQL database performance. 
• Also, when the SQL indexes are fragmented, they result in inefficient usage of disk storage due to the scattered pages in the index. 

Due to higher index fragmentation, more resources are consumed, and this further leads to database performance degradation and slower query execution. To resolve this issue, one of the most optimal solutions is the MSSQL index rebuild process. Let’s now gain a deeper understanding of this process and learn how it will help users improve database performance. 

MSSQL Index Rebuild – A Complete Overview

With the SQL Index fragmentation in the database, the major impact shows on the performance. This is where the MSSQL rebuild index method helps. This method can be considered as properly reorganizing and managing the SQL index to improve the index functions. Rebuilding the index creates an entirely new structure to fix the older, fragmented index on the server. By reorganizing the index into a new structure, the data in the index becomes more organized and efficient to access. 

After the users rebuild the fragmented indexes in the SQL Server database, they can see the improvement in SQL query performance and reduced storage space. The MSSQL index rebuild method offers dual options for implementation. Users can either perform the Offline Rebuild or go for Online rebuild mode. But what is the difference between the two? Let’s take a look.

• Offline SQL Index Rebuild: The offline rebuild option allows rebuilding the SQL index without any other user’s interference during the rebuild process. In this rebuild option, the table is locked until the entire rebuild operation is completed.
  
• Online SQL Index Rebuild: As the name suggests, the online rebuild option allows users to access the table even when the rebuild operation is in process. 

Both these methods are helpful to rebuild the index in SQL Server database and can eventually help in improving the overall database health. So far, we have read and learned that the index fragmentation issue can be resolved by MSSQL index rebuild, which is practically creating a new index structure and reorganizing the data in the newly created index. 

Now, the question arises, what is the difference between MSSQL rebuild index and reorganizing the SQL index? To proceed with the solution effectively, let’s now understand these differences and then continue to resolve this issue. 

MSSQL Index Rebuild vs Reorganize: What’s the Difference?

Both these terms can be a little confusing for users who aren’t much aware of the technicalities and SQL Server. To simplify the meaning of these two methods, we will now take a look at the differences between rebuilding and reorganizing. 

• When we talk about rebuilding the SQL index, it generally specifies dropping the old fragmented index and creating a new one from scratch. On the other hand, reorganizing the index means rearranging the cluttered pages in the index without deleting them. 
• In the rebuild process, more resources such as memory, CPU, and disk I/O are used, whereas in the reorganizing method, fewer resources are used, making it a lighter process. 
•  When the rebuild process is initiated, the tables might get locked to avoid user interference during the process(in case the users are using the Online Rebuild process, the tables are not locked). Index reorganizing is done online, allowing users to access the tables during the process. 
• The MSSQL index rebuild process is mainly done when the index fragmentation is more than 30%. Whereas, the fragmentation ranging between 5% and 30% can be resolved by reorganizing the indexes only. 

These are all the major differences between the methods. We are now well aware of the MSSQL index rebuild vs reorganize differences. Now, it’s time to understand and learn the steps for rebuilding the index and how the method can be implemented without any errors.

How to Rebuild SQL Indexes With Complete Precision? All Methods Explained

To rebuild the index without any errors and with complete precision, it is required for the users to understand the method first. Then only they can efficiently proceed with the method and further resolve and repair their fragmented indexes to improve the database performance. We will now take a look at how the commands to rebuild the index work and are executed. 

Scenario 1: To Rebuild a Specific Index in SQL Server Database

In case the user wishes to rebuild only a specific index in their database, they can execute the below given command and resolve the issues regarding their SQL Server indexes. 

Here is the command that will help the users with MSSQL index rebuild:

In case the user needs to rebuild the index in online mode, the command becomes:

Here, we have explicitly mentioned the index and schema we are referring to for the rebuild process. 

Scenario 2: To Rebuild All Indexes in SQL Server Database

Now we will take a look at the command that will help the users to rebuild all the indexes in the affected SQL Server database. Below, we have mentioned the command that will allow users to rebuild all indexes to improve database performance. 

With the help of these commands, users can efficiently fix the issues related to index fragmentation and further improve the database performance for better use. However, there are certain situations where the users have less technical expertise, and for them, implementing these T-SQL commands might be complex. In such cases, users can rebuild the index using SSMS. Let’s see how the method works and how to execute it efficiently. 

MSSQL Index Rebuild Using SQL Server Management Studio

The T-SQL commands are efficient for rebuilding the index in the database. However, for situations where the users aren’t very familiar with SQL queries, we can also go with SQL Server Management Studio. SSMS offers a friendly user interface to operate and work on SQL Server issues. Given below are the steps to use SSMS to rebuild the SQL Index:

1. Open SQL Server Management Studio and connect to the SQL Server instance. 
2. Go to the object explorer and locate the target database.
3. Expand the database, and find the Tables option from there. 
4. Under the Tables section, look for the Indexes folder. Expand the Indexes folder to preview all the indexes of the table. 
5. Then, right-click on the Indexes and select the Rebuild Option from the menu. 
6. Configure the required Rebuild settings in the window, and then click OK to proceed with the Index Rebuild Process. 

These steps will help the users to rebuild the database in a more efficient way. The friendly interface of the tool allows users to work effectively to resolve the index fragmentation issue. 

Common Challenges Encountered While MSSQL Index Rebuild

While proceeding with the rebuild operation in the SQL Indexes, there are a few challenges that the users might come across. These challenges can result in bigger issues if not dealt with in time. We will now take a look at the challenges and then learn the best practices to avoid such issues. 

• One of the most common challenges is dealing with large indexes during the rebuild process. Rebuilding large indexes might take a much longer time and further consume more resources during the process. 
• Another challenge is that with the tables locked during the ebuild process, users might face slower application performance or timeouts. 
• When the user executes the rebuild process, before deleting the old index, the server creates the new index. It means that for a temporary period, a double amount of storage is being used on the disk. This can lead to an insufficient disk space issue. 

With these challenges, it sometimes becomes more complex for the users to further proceed with the MSSQL Index Rebuild task. Users must understand these issues well before beginning the rebuild process. Now, we will take a look at the best practices that will help with a safer and more efficient index rebuilding, and further, to keep the index well-organized and managed. 

Best Practices To Keep SQL Indexes Healthy 

To keep the database indexes healthy and secure for optimal database performance, here are the best practices. 

• It is crucial to monitor the indexes regularly to prevent the risk of fragmentation in the indexes. For a better idea, users can set the thresholds to track and know when the indexes need repairing. 
  • 0-5% fragmentation – Certainly no action required in the index. 
  • 5-30% fragmentation – The Index needs to use slight reorganization.
  • More than 30% – Users need to rebuild the entire index to repair the issue. 
• For better SQL database health, users must know when to use the rebuild method and when they need the reorganize method. 
• It is also important to schedule the index rebuild process during non-production hours to avoid affecting the workflow for the users.
• Maintaining indexes is just as important as unused indexes might result in storage full issues and further affect the database performance. Hence, removing the unused indexes is a necessary step. 

Conclusion

With the help of this technical write-up, we have learned the importance of the MSSQL index rebuild process. We have also understood how it can help users with the fragmented index issue. Additionally, we also mentioned the differences between MSSQL index rebuild vs reorganize to make it easier for the users to understand when they need which method. By following this guide, users can effectively repair and resolve the issues in the SQL Indexes and further make the database faster.