On August 4th, 2021, Microsoft released SQL Server 2019 Cumulative Update 12. This is Build 15.0.4153.1. By my count, there are 29 public fixes and improvements in this CU, so it is about average size. It is always a good idea to read through the CU KB article to see more information about each fix and improvement.
There is a post in the Microsoft Tech Community that has a few more details.
No Service Packs
SQL Server 2017 and newer does not have Service Packs. Microsoft is not using Service Packs as a servicing mechanism for SQL Server, only cumulative updates.
Microsoft released a new CU every month for SQL Server 2019 for the first four months after GA. Due to human malware concerns, CU5 was delayed until June 22, 2020. From CU6 through CU8, they seemed to be back to a normal monthly release schedule.
Then Microsoft announced a release delay in order to give their employees some well deserved time off over the holidays. After that, there was silence until the Extended Events security update was released on January 12th, 2021.
Since SQL Server 2019 has been GA for more than a year, Microsoft has switched to releasing a new CU every two months. This is what they will do until SQL Server 2019 falls out of Mainstream Support on January 7, 2025. When SQL Server 2019 falls out of Mainstream Support, there won’t be any more cumulative updates.
SQL Server cumulative updates are actually cumulative, which might seem obvious from the name. This means that when you install SQL Server 2019 CU12, 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, and they have also added a significant number of product improvements and new features since the RTM release.
Despite some recent stumbles by Microsoft (including SQL Server 2019 CU7), 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, but 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.
Here is Microsoft’s official guidance:
Microsoft recommends ongoing, proactive installation of CUs as they become availableKB5004524 – Cumulative Update 12 for SQL Server 2019 (microsoft.com)
- 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.
If you have any questions about this post, please ask me here in the comments or on Twitter. I am pretty active on Twitter as GlennAlanBerry. Thanks for reading!