How to fix Error 4906 on Windows Server 2025 / Windows 11

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Troubleshooting Guide: SQL Server Error 4906 – Partition Compatibility Mismatch

Why This Error Happens

This error occurs when attempting to create or rebuild an index on a table where the partitioning scheme of the table does not match the partitioning scheme of the index being applied. SQL Server requires that when an index is explicitly partitioned (or aligned), the base table and the index must share the same partition function and partitioning columns to maintain partition alignment. This mismatch typically happens after a table has been repartitioned, moved to a different filegroup, or when a partitioned index is mistakenly created against a non-partitioned (or differently partitioned) table in SQL Server 2025.

Step-by-Step Resolution Guide

Step 1: Verify the Current Partitioning State of the Table

  • Run the following query to check if the table is partitioned:
SELECT t.name AS TableName, i.name AS IndexName, p.partition_number, ps.name AS PartitionScheme
FROM sys.tables t
JOIN sys.indexes i ON t.object_id = i.object_id
JOIN sys.partitions p ON i.object_id = p.object_id AND i.index_id = p.index_id
LEFT JOIN sys.partition_schemes ps ON i.data_space_id = ps.data_space_id
WHERE t.name = 'YourTableName';
  • Confirm whether the table uses a partition scheme or resides on a single filegroup.

Step 2: Check the Partition Function and Scheme Definitions

  • Inspect the partition function and scheme assigned to the table:
SELECT * FROM sys.partition_functions;
SELECT * FROM sys.partition_schemes;
  • Ensure the index creation statement references the exact same partition scheme name as the base table (not just a similarly named one).

Step 3: Recreate the Index with Matching Partition Alignment

  • Drop the conflicting index using DROP INDEX IndexName ON TableName;.
  • Recreate the index explicitly specifying the correct partition scheme to match the table:
CREATE INDEX IX_YourIndex
ON dbo.YourTableName (ColumnName)
ON YourPartitionScheme(PartitionColumn);
  • If the table itself is not partitioned, create the index without the ON PartitionScheme clause so it aligns as a non-partitioned index.

Step 4: Align Table and Index Partitioning via Rebuild (If Mismatch Persists)

  • If the table was recently repartitioned, rebuild the clustered index first to re-align data:
ALTER INDEX ALL ON dbo.YourTableName REBUILD PARTITION = ALL;
  • This forces SQL Server 2025 to redistribute data pages according to the current partition scheme before non-clustered indexes are applied.

Alternative or Verification Steps

  • After recreating the index, run sp_helpindex 'YourTableName' or query sys.indexes to confirm the data_space_id of the index matches the data_space_id of the table’s partition scheme.
  • If the error persists despite matching schemes, check for orphaned statistics or metadata corruption by running DBCC CHECKTABLE('YourTableName') WITH DATA_PURITY and consider rebuilding the table in a new filegroup as a fallback.