| title | SQL Server 2025 Release Notes | |
|---|---|---|
| description | Find information about SQL Server 2025 (17.x) limitations, known issues, help resources, and other release notes. | |
| author | MikeRayMSFT | |
| ms.author | mikeray | |
| ms.reviewer | randolphwest | |
| ms.date | 06/19/2025 | |
| ms.service | sql | |
| ms.subservice | release-landing | |
| ms.topic | release-notes | |
| ms.custom |
|
|
| monikerRange | >=sql-server-2016 |
[!INCLUDE sqlserver2025]
This article describes requirements, limitations, and known issues for [!INCLUDE sssql25-md].
This article is updated for community technology preview (CTP 2.1).
For hardware and software requirements, see Hardware and software requirements for SQL Server 2025 Preview.
Issue: SQL Server instances on Windows might fail to start after the installation if the machine has more than 64 logical cores per NUMA node.
For more information, see Limit number of logical cores per NUMA node to 64.
Issue: SQL Server instances on Linux might fail to start if the machine uses an Intel 12th Gen or later hybrid architecture CPU, and the host operating system is Linux.
You might see an error message similar to the following output:
Reason: 0x00000004 Message: ASSERT: Expression=(result * DrtlGetProcessorCoreCount() == DrtlGetProcessorCount()) File=LibOS\Windows\Kernel\SQLPal\common\dk\sos\src\sosnumap.cpp Line=208
If you want to use a Linux host operating system, you can work around the issue by disabling efficiency cores (E-cores) in your BIOS. If you use containers, or a hypervisor like Hyper-V on Windows (including WSL), you aren't affected.
[!INCLUDE sssql25-md] doesn't support in place upgrades from previous versions of [!INCLUDE ssnoversion-md], including SQL Server 2025 CTP releases.
There's a known issue when attempting to set the backup compression algorithm to ZSTD.
When specifying the ZSTD algorithm (backup compression algorithm = 3), the following error message returns:
Msg 15129, Level 16, State 1, Procedure sp_configure `3` is not a valid value for configuration option 'backup compression algorithm'.
Use the new compression algorithm directly in the BACKUP Transact-SQL command instead of setting the server configuration option.
Queries that use the built-in SESSION_CONTEXT function might return incorrect results or trigger access violation (AV) dumps when executed in parallel query plans. This issue stems from the way SESSION_CONTEXT interacts with parallel execution threads, particularly when the session is reset for reuse.
For more information, see the Known issues section in SESSION_CONTEXT.
When the Optional parameter plan optimization feature encounters a predicate that is based on a LOB column, an access violation exception can occur. A fix has been identified and will be part of the next preview release of SQL Server 2025.
Large object (LOB) data types in the Database Engine can store data that exceeds 8,000 bytes. These data types store data on a row-overflow data page. A LOB also encompasses data types that store data on dedicated LOB page structures, which use a text or image pointer of in-row references to LOB data pages. For more information about data storage, see Pages and extents architecture guide.
| Build | Version number | Date |
|---|---|---|
| Preview (CTP 2.1) | 17.0.800.3 | June 16, 2025 |
| Preview (CTP 2.0) | 17.0.700.9 | May 19, 2025 |