Troubleshooting Guide: SQL Server Error 13088 on ALTER Operations
Why This Error Happens
Error 13088 in Microsoft SQL Server 2025 typically occurs when attempting an ALTER operation on a memory-optimized table, filegroup, or Service Broker-related object while the underlying structure is in an inconsistent or locked state. This is commonly triggered by insufficient permissions on the database principal executing the ALTER statement, a conflicting schema lock held by another session, or corruption in the metadata associated with In-Memory OLTP filegroups. On Windows Server 2025 / Windows 11 hosts, this can be compounded by file system-level permission restrictions on the data directory where the memory-optimized filegroup container resides.
Step-by-Step Resolution Guide
Step 1: Verify Current Permissions and Session Locks
- Open SQL Server Management Studio (SSMS) and connect using an account with
sysadminordb_ownerrights. - Run the following query to check for blocking sessions:
SELECT * FROM sys.dm_exec_requests WHERE blocking_session_id <> 0;
- If a blocking session is found tied to the target table/filegroup, note the
session_idfor termination in Step 2.
Step 2: Terminate Conflicting Sessions and Retry the ALTER Statement
- Kill the blocking session identified above using:
KILL <session_id>;
- Re-run your original
ALTER TABLEorALTER DATABASEcommand. - If the error persists, check the SQL Server Error Log (
C:\Program Files\Microsoft SQL Server\MSSQL17.MSSQLSERVER\MSSQL\Log\ERRORLOG) for additional context tied to Error 13088.
Step 3: Validate Filegroup and File System Permissions
- Navigate to the data directory tied to the memory-optimized filegroup, typically located at
C:\Program Files\Microsoft SQL Server\MSSQL17.MSSQLSERVER\MSSQL\Data\. - Right-click the folder, select Properties > Security, and confirm the SQL Server service account (e.g.,
NT Service\MSSQLSERVER) has Full Control. - Restart the SQL Server service via
services.mscor by running:
Restart-Service -Name MSSQLSERVER -Force
Step 4: Rebuild or Repair the Affected Object (If Needed)
- If the
ALTERcommand still fails, script out the table definition and recreate it in a new filegroup:
EXEC sp_helptext 'YourTableName';
- Drop and recreate the object using the scripted definition after resolving permission/lock issues.
Alternative or Verification Steps
- To verify the fix, re-run the original
ALTERstatement and confirm it completes without Error 13088; also checksys.dm_db_session_space_usageto ensure no residual locks remain. - As an alternative, if the issue persists, restore the database from a recent backup to a test instance and attempt the
ALTERoperation there to isolate whether the corruption is instance-specific or embedded in the database file itself.