FIX: Checkpoint and backup operations fail with error 2601 when Change Tracking is enabled for a database in SQL Server 2014

Applies to: SQL Server 2014 DeveloperSQL Server 2014 EnterpriseSQL Server 2014 Enterprise Core


Assume that you have enabled the Change Tracking feature for a database in Microsoft SQL Server 2014. When you perform backup or checkpoint operations on the database, the operations fail with error 2601. Additionally, error messages that resemble the following are logged in the SQL Server error log.

Cannot insert duplicate key row in object 'sys.syscommittab' with unique index 'si_xdes_id'. The duplicate key value is (KeyValue).

Error: 3999, Severity: 17, State: 1.

Failed to flush the commit table to disk in dbid DatabaseID due to error 2601. Check the errorlog for more information.


This issue is fixed in the following cumulative update for SQL Server:

       Cumulative Update 6 for SQL Server 2014 SP2


Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.


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