Compatibility levels determine how certain features of SQL Server behave, allowing databases to maintain functionality even as the server itself evolves. However, changing compatibility levels requires careful consideration to balance the benefits of new features against the potential risks of disrupting existing applications. This blog explores the importance of handling compatibility level changes thoughtfully during SQL Server upgrades, highlighting the risks of making changes too hastily and the advantages of adopting new compatibility levels within a reasonable timeframe.
Month: December 2024
Leveraging SQL Server 2019’s Last Known Actual Query Plan for Troubleshooting
Troubleshooting production performance issues is often challenging because detailed query execution data can vanish before you realize there’s a problem. Many times, you end up piecing together incomplete clues from runtime statistics or the plan cache. Fortunately, SQL Server 2019 introduced a powerful feature to address this pain point: the Last Known Actual Query Plan.
Using sp_getapplock to Prevent Concurrent Execution of Stored Procedures in SQL Server
In multi-user database environments, ensuring the integrity and consistency of data is essential. One common challenge is preventing multiple instances of the same stored procedure from executing at the same time, which can lead to data conflicts, race conditions, and unpredictable results. To address this, SQL Server provides a powerful tool called sp_getapplock. This post explains what sp_getapplock is, what you are actually locking when you use it, how to implement it to prevent concurrent executions of a stored procedure, and the difference between transaction-level and session-level locks.
Understanding Worker Threads vs. CPU Utilization in SQL Server
When managing SQL Server performance, it’s important to understand the relationship—and the distinction—between worker threads and CPU utilization. These are two separate metrics that can behave independently. For instance, you might experience high CPU utilization while still having available worker threads, or you could have all worker threads occupied even when CPU utilization is low. This post takes a look at SQL Server worker threads and CPU utilization.
Exploring Programming Constructs in T-SQL – Part 3: Error Handling and Transaction Management
Welcome back to our series on programming constructs in T-SQL! In the previous installments, we explored variables, conditional IF statements, loops, and CASE expressions. These tools have helped us write dynamic and efficient SQL scripts. In this third part, we’ll focus on two essential concepts for writing reliable SQL code: Error Handling with TRY…CATCH Blocks and Transaction Management.
SQL Server’s Query Store: Understanding Plan Forcing and Performance Optimization
The Query Store in SQL Server is a powerful feature that enables database administrators and developers to track and analyze query performance over time. By storing runtime statistics and execution plans, it provides invaluable insights into how queries behave and how they can be optimized. This blog looks into the mechanics of the Query Store, the necessity of plan forcing, and how to effectively use it to stabilize and enhance query performance.