How to fix Error 2726 on Windows Server 2025 / Windows 11

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Why This Error Happens

This error occurs when the partition function definition specifies a different number of columns than what is referenced in the CREATE TABLE or CREATE INDEX statement’s partition scheme mapping. SQL Server 2025 strictly validates that the column count in PARTITION BY RANGE matches the partitioning key columns supplied when the table or index is created. This mismatch typically arises from schema drift after a partition function was altered, or from a copy-paste error when scripting multi-column partitioning across environments.

Step-by-Step Resolution Guide

Step 1: Identify the Partition Function Definition

  • Run the following query to inspect the current partition function and its column count:
  SELECT pf.name AS PartitionFunction, pf.fanout, pp.boundary_id, 
         pf.boundary_value_on_right
  FROM sys.partition_functions pf
  JOIN sys.partition_range_values pp ON pf.function_id = pp.function_id
  WHERE pf.name = 'YourPartitionFunctionName';
  • Confirm the number of parameter columns declared in the original CREATE PARTITION FUNCTION script.

Step 2: Review the Partition Scheme and Table Mapping

  • Check sys.partition_schemes and sys.partition_parameters to see how many columns the scheme expects versus what the table/index definition provides.
  • Open the CREATE TABLE script and verify the ON PartitionSchemeName (Column1, Column2, ...) clause column count matches the partition function’s parameter list exactly.

Step 3: Drop and Recreate the Partition Function with Correct Columns

  • If a mismatch is confirmed, drop the dependent objects (indexes, constraints) referencing the partition scheme first:
  DROP PARTITION SCHEME YourPartitionScheme;
  DROP PARTITION FUNCTION YourPartitionFunction;
  • Recreate the function with the exact number of columns needed:
  CREATE PARTITION FUNCTION YourPartitionFunction (int, int)
  AS RANGE LEFT FOR VALUES (10, 20, 30);
  • Rebuild the partition scheme and reattach it to the table using the matching column list in your CREATE TABLE or CREATE INDEX statement.

Step 4: Rebuild Affected Indexes

  • After recreating the partition scheme, rebuild any clustered or non-clustered indexes that reference the old scheme:
  ALTER INDEX ALL ON YourTableName REBUILD;
  • This ensures SQL Server 2025 re-validates column alignment across all partition-aligned structures.

Alternative or Verification Steps

  • Verify the fix by querying sys.partition_functions and sys.indexes to confirm the fanout and column counts align with your table schema, then run a test INSERT across partition boundaries to ensure no Error 2726 is thrown.
  • If the issue persists, use SQL Server Management Studio’s Generate Scripts wizard to export the full partitioning DDL, manually audit column order/type, and reapply it in a maintenance window to avoid further drift.