How to fix Error 482 on Windows Server 2025 / Windows 11

by

Troubleshooting Guide: SQL Server Error 482 – Invalid Expression in TABLESAMPLE or REPEATABLE Clause

Why This Error Happens

This error occurs because SQL Server requires the TABLESAMPLE clause to use a constant numeric expression (either a percentage or a fixed number of rows) that can be resolved at parse time. Similarly, the REPEATABLE clause requires a constant integer seed value and cannot reference variables, subqueries, or non-deterministic functions. When a query attempts to pass a column reference, a variable, or a computed expression into either clause, SQL Server rejects the statement because it cannot evaluate the sampling size or seed before query execution begins.

Step-by-Step Resolution Guide

Step 1: Review the Query Syntax for TABLESAMPLE

  • Open the query in SQL Server Management Studio (SSMS) or Azure Data Studio and locate the TABLESAMPLE clause.
  • Confirm that the value is a literal constant, such as TABLESAMPLE (10 PERCENT) or TABLESAMPLE (1000 ROWS).
  • Remove any variable references like TABLESAMPLE (@SampleSize PERCENT), as these are not supported.

Step 2: Replace Variables with Hardcoded Constants

  • If your application dynamically builds the sample size, refactor the query to use dynamic SQL instead of parameterized variables.
  • Example fix using dynamic SQL execution:
  DECLARE @SQL NVARCHAR(MAX);
  DECLARE @SamplePercent INT = 10;
  SET @SQL = N'SELECT * FROM dbo.YourTable TABLESAMPLE (' + CAST(@SamplePercent AS NVARCHAR(10)) + N' PERCENT)';
  EXEC sp_executesql @SQL;
  • Ensure the concatenated value resolves to a literal integer before execution.

Step 3: Correct the REPEATABLE Clause Value

  • Check that the REPEATABLE seed is a constant integer literal, such as REPEATABLE (4529).
  • Remove any function calls (e.g., RAND(), NEWID()) or column references inside the REPEATABLE parentheses.
  • If a “random-like” seed is needed, generate the integer value in application code first, then inject it as a literal into the query string.

Step 4: Validate Query Plan Compatibility

  • Run the corrected query in SSMS and check the Messages tab for successful execution without Error 482.
  • Use SET SHOWPLAN_ALL ON to confirm the optimizer can generate an execution plan without needing runtime evaluation of the sample size.
  • Restart the SQL Server Agent job or application service if the query was embedded in a stored procedure that was cached with the invalid syntax.

Alternative or Verification Steps

  • Verify the fix by executing the query directly against a test table (e.g., SELECT * FROM dbo.Test TABLESAMPLE (5 PERCENT) REPEATABLE (100);) and confirming rows are returned without error.
  • If constants are still rejected, check for hidden data type mismatches (e.g., passing a DECIMAL where an INT is expected) by explicitly casting the literal using CAST(10 AS INT) within the clause.