How to fix Error 8057 on Windows Server 2025 / Windows 11

by

Troubleshooting Guide: Error 8057 – Table-Valued Parameter Structure Mismatch

Why This Error Happens

Error 8057 occurs when SQL Server 2025 detects a mismatch between the structure of a table-valued parameter (TVP) passed from the client application and the user-defined table type expected by the stored procedure or query. This typically happens due to column count discrepancies, data type mismatches, or ordinal position errors between the DataTable/DbDataReader object in the calling application and the server-side TYPE definition. It can also surface after a schema change to the user-defined table type that wasn’t propagated to the client-side code or cached execution plans.

Step-by-Step Resolution Guide

Step 1: Validate the User-Defined Table Type Schema

  • Connect via SQL Server Management Studio (SSMS) 21 and run the following to inspect the expected structure:
  SELECT c.name, t.name AS data_type, c.max_length, c.column_id
  FROM sys.table_types tt
  JOIN sys.columns c ON tt.type_table_object_id = c.object_id
  JOIN sys.types t ON c.user_type_id = t.user_type_id
  WHERE tt.name = 'YourTableTypeName'
  ORDER BY c.column_id;
  • Compare the output (column order, names, and data types) directly against the client-side DataTable or SqlDataRecord structure.

Step 2: Correct the Client-Side Application Code

  • Ensure the DataTable column order in your .NET (C#) code matches the server-side type exactly; SQL Server binds TVP columns by ordinal position, not by name.
  • Verify data type precision (e.g., DECIMAL(18,2) vs DECIMAL(10,2)) matches exactly between the C# SqlMetaData definitions and the SQL Server type.
  • If using Entity Framework Core or Dapper, clear any cached metadata by restarting the application pool in IIS or the host process.

Step 3: Clear Cached Execution Plans and Procedure Cache

  • If the table type was recently altered (e.g., a column was added or resized), stale execution plans may still reference the old structure.
  • Run the following on the specific database to force a recompile:
  DBCC FREEPROCCACHE;
  • Alternatively, target just the specific stored procedure to avoid a full cache flush:
  EXEC sp_recompile 'dbo.YourStoredProcedureName';

Step 4: Check for Windows Server 2025 / SQL Server 2025 Driver Compatibility

  • Confirm the Microsoft ODBC Driver or SqlClient (Microsoft.Data.SqlClient) NuGet package version is updated to the latest release compatible with SQL Server 2025, as older drivers may misinterpret new column metadata extensions.
  • Navigate to C:\Windows\System32\drivers or check installed ODBC drivers via odbcad32.exe to confirm the driver version matches server requirements.

Alternative or Verification Steps

  • Run a manual test execution of the stored procedure using sqlcmd from the Windows 11 terminal with a hardcoded TVP insert statement to isolate whether the issue is server-side or application-side.
  • If the error persists after schema validation, drop and recreate the user-defined table type entirely (rather than altering it) to eliminate any hidden metadata corruption in sys.table_types.