On March 31, 2020, Microsoft released SQL Server 2019 CU4, which is Build 15.0.4033.1. By my count, there are 36 public hotfixes in this cumulative update. This is about an average number of fixes. It was released a couple of weeks earlier than I expected, based on the calendar.
Since SQL Server 2019 does not have service packs, Microsoft has been including actual new features and product improvements in CUs. This is another reason to try to stay current on your cumulative updates.
Microsoft will be releasing a new CU every month for the first twelve months after GA. After the first year, they will then release a new CU every two months for the next four years. After five years, SQL Server 2019 will fall out of Mainstream support. This means there won’t be any more cumulative updates after that, only security fixes. SQL Server 2019 will fall out of Mainstream Support on January 7, 2025.
Here is Microsoft’s official guidance:
Microsoft recommends ongoing, proactive installation of CUs as they become availablehttps://support.microsoft.com/en-us/help/4548597/cumulative-update-4-for-sql-server-2019
- SQL Server CUs are certified to the same levels as Service Packs, and should be installed at the same level of confidence.
- Historical data shows that a significant number of support cases involve an issue that has already been addressed in a released CU.
- CUs may contain added value over and above hotfixes. This includes supportability, manageability, and reliability updates.
SQL Server cumulative updates are actually cumulative, which might seem obvious from the name. This means that when you install SQL Server 2019 CU4, you are going to get all of the hotfixes and product improvements from ALL of the previous CUs. Microsoft has fixed hundreds of bugs since SQL Server 2019 RTM. They have also added a significant number of product improvements and new features since the RTM release.
Despite some recent stumbles by Microsoft, I am still a big proponent of trying to keep your SQL Server instances as up to date as possible. That does not mean throwing a new CU into Production the day it is released. It also does not mean avoiding patching SQL Server indefinitely either. You really are better off trying to stay as current as possible on your SQL Server builds.
I recently updated my post about Performance and Stability Fixes in SQL Server 2019 CU Builds for SQL Server 2019.
Please let me know what you think in the comments. Thanks for reading!