How to fix Error 2950 on Windows Server 2025 / Windows 11

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Troubleshooting Guide: SQL Server Error 2950 – Integer Overflow Exception

Why This Error Happens

Error 2950 occurs when SQL Server attempts to perform a calculation or data conversion that exceeds the maximum value boundary of the designated integer data type (such as int or smallint). This is commonly triggered by corrupted statistics pages, oversized aggregate operations in query plans, or arithmetic operations on columns that lack proper bounds checking. In some cases, outdated database compatibility levels on Windows Server 2025 can cause the query optimizer to miscalculate memory grants, resulting in this overflow.

Step-by-Step Resolution Guide

Step 1: Identify the Offending Query or Process

  • Open SQL Server Management Studio (SSMS) and check the SQL Server Error Log located at C:\Program Files\Microsoft SQL Server\MSSQL17.MSSQLSERVER\MSSQL\Log\ERRORLOG.
  • Look for the specific Transact-SQL statement or stored procedure referenced alongside Error 2950.
  • Run DBCC CHECKDB('YourDatabaseName') to rule out underlying corruption causing miscalculated values.

Step 2: Adjust Data Type Definitions

  • Identify columns involved in the failing calculation using sp_help 'TableName'.
  • If the operation involves SUM() or multiplication, convert the column data type from int to bigint to accommodate larger value ranges:
  ALTER TABLE YourTable ALTER COLUMN YourColumn BIGINT;
  • Rebuild any affected indexes post-conversion using ALTER INDEX ALL ON YourTable REBUILD;.

Step 3: Update Database Compatibility Level

  • Verify the current compatibility level by running:
  SELECT name, compatibility_level FROM sys.databases WHERE name = 'YourDatabaseName';
  • Update the database to align with SQL Server 2025 standards (level 170):
  ALTER DATABASE YourDatabaseName SET COMPATIBILITY_LEVEL = 170;
  • Restart the SQL Server (MSSQLSERVER) service via services.msc on Windows Server 2025 to apply optimizer changes.

Step 4: Apply the Latest Cumulative Update (CU)

  • Navigate to the Microsoft Update Catalog and download the latest Cumulative Update for SQL Server 2025.
  • Run the installer as an Administrator to patch known optimizer bugs related to integer handling.
  • Reboot the server to finalize the patch installation.

Alternative or Verification Steps

  • Verification: Re-run the original query or scheduled job that triggered Error 2950; monitor the Activity Monitor in SSMS to confirm the execution plan completes without memory grant warnings.
  • Alternative: If the error persists after type conversion, use SET ARITHABORT ON at the session level to force the query to terminate safely rather than returning corrupted overflow data, then review the application-side logic generating the oversized values.