Performance tuning for SQL Server: Best practices

The key to effective SQL Server performance tuning is figuring out where queries run slowly or must be optimized to run faster or more efficiently. Proactive or reactive SQL Performance tuning is possible. Preventing future issues with performance tuning for SQL Server is the goal of proactive techniques. Techniques for reactive tuning SQL Server respond as soon as an issue arises.

Performance tuning best practices for SQL Server include:

• Indexing with care: The purpose of indexes is to enable fast retrieval of data, allowing fast selection of rows. Indexing should be done carefully to avoid bottlenecks.
• Avoiding coding loops: In other words, avoid overflowing a query and repeating it.
• Avoiding correlating SQL subqueries: A subquery is a child query that takes a row at a time. Usually, this takes some time.

It is easy to determine where you should concentrate your tuning efforts by observing wait times and statistics. As user requests are routed by SQL Server, threads are managed. DBAs can identify queries that are not performing well by monitoring the thread performance. Tuning is aimed at reducing response time (the time elapsed between sending a statement and receiving a response) and optimizing throughput (the amount of space and processing resources required for one statement to execute).

DBAs need insight into all databases and server layers to figure out the cause of a SQL Server performance problem. The performance tuning tools for SQL Server provide you with a better understanding of top SQL statements, blocked queries, wait types, and how missing indexes impact performance.

Use the following best practices for optimizing your SQL Server and database performance with SolarWinds DPA:

1. Conduct Response Time Analysis

SQL Server query performance can be enhanced using response time analysis, a pragmatic approach that lets you deliver results that are noticeable. It is called wait time analysis and allows IT teams to align the quality of service they deliver to their customers more effectively. By analyzing the actual time it takes for an operation to complete, wait methods prevent guessing what the impact will be on performance. Response time analysis is a priority for SolarWinds DPA.

2. Resource provisioning and response times: An analysis

It makes it easier to take a more prescriptive approach to hardware recommendations by aligning resource provisioning with database performance. Using the SQL query analyzer, you can see how resource provisioning impacts response times. Developers can also take advantage of this feature to gain a deeper understanding of their VMware infrastructure and how it influences overall database performance.

3. Examine historical trends

Using DPA’s historical data repository you can spot trends and anomalies in your SQL tuning efforts. With DPA, you can quickly identify and resolve performance issues and bottlenecks by looking back in time (from five seconds ago to five years ago).

4. Know Tables and Row Counts

Be sure to use tables instead of views and table-valued functions when you implement SQL Server performance tuning techniques. Functions with table values have different performance implications. As a part of the Table Tuning Advisor function in DPA, you can see aggregate information about your table, such as row count, churn, and fragmentation.

6. Understand Table Selectivity

You should be able to determine the number of rows you’ll be working with or the size of the actual set, if you’ve implemented the two tips above. For effective tuning, you need to understand the concept of table selectivity in depth.queries and query selectivity is also recommended. A powerful and useful tool like this.

10. Record Results

Tuning SQL Server requires recording your results. If you do this, you’ll be able to see how the changes will affect the enterprise.

11. Adjust Queries 

If too many changes are made too soon, the changes can cancel each other out and be ineffective. Consider the most expensive procedures first-there is no one-size-fits-all answer. Rather, seek out the best possible solution to the given problem.

14. Identification of Performance Inhibitors

Look for multi-occurrences of performance inhibitors. Code first generators, scalar functions, cursors, nested views, and row-by-row processing might be used.

Data Modification with SQL

By deleting or modifying data, or by writing new data, SQL changes data. In case of a power outage before the SQL server writes data back to disk, all modifications are written to the transaction log (which sits on disk where it is safe).

Once a page has not been accessed for a certain time, it is written to disk again. Transactions are marked as written in the transaction log once they have been written to disk (.mdf/.ndf file). The SQL server can retrieve and add completed transactions to the database (.mdf and .ndf) files once the power is restored if a power outage occurred.