When your SQL Server isn’t performing as expected, it’s tempting to think that upgrading hardware is the quick fix. More CPUs, extra memory, faster disks—they all sound like solutions that should solve the problem. But before you start investing in new equipment, it’s worth taking a step back to see if optimization can address the issues.
Category: Statistics
Ensuring Optimal Execution Plans in SQL Server
Explore professional strategies for managing SQL Server Plan Regression. This guide offers insight into preventing performance degradation through efficient execution plan selection and maintenance, ensuring optimal query performance in SQL Server environments.
SQL Server’s Query Optimizer: Bridging the Gap to Peak Performance
We are always in search of ways to optimize query performance. At the heart of achieving these goals within SQL Server is the Query Optimizer, a sophisticated component of the SQL Server Database Engine. Its primary role is to evaluate various potential execution plans for a given query and select the most efficient path forward. This process is necessary for minimizing resource consumption and execution time, while enhancing the overall performance and scalability of database operations.
Navigating Asynchronous Statistics Updates in SQL Server 2022
Keeping database statistics updated is crucial for the smooth functioning of your queries. The database engine is pretty smart; it automatically refreshes these statistics to stay in sync with changes in your data. This is key for the query optimizer, the brain behind the scenes, to churn out the most efficient plans for your queries. While up-to-date statistics often improve query plan quality, the extra time added to some query executions due to statistics update may be undesirable, particularly in transactional workloads with short queries, where updating statistics may take longer than query execution itself. For this reason, the SQL Server database engine also supports an option to update statistics asynchronously.
SQL Server AGs: Tackling Missing and Stale Statistics for Readonly Secondaries
In SQL Server’s Always On Availability Groups, understanding the behavior of statistics on secondary replicas is key to maintaining query performance. This post explores the challenges and solutions for managing statistics in read-only secondary databases and snapshots. We delve into two critical scenarios: the creation of statistics in secondary replicas when they are missing on the primary, and the handling of stale statistics due to differences in primary and secondary workloads.
Optimizing SQL Server 2022: Leveraging Auto-Drop Statistics
Auto-Create statistics is a well-known feature critical for the database performance. When one statistic is auto created, changing the table structure is not blocked by the presence of the statistic. An auto-created statistics is also dropped automatically when a schema change happens. On the other hand, if the statistic is created by the user, any schema change will be blocked by the presence of the statistic. The Auto-Drop setting on a statistic is a new SQL Server 2022 feature to change this behavior.