FIX: Error 35377 when you run a parallel query that contains MERGE statements in SQL Server 2014


Assume that you enable the Multiple Active Result Sets (MARS) feature in Microsoft SQL Server 2014, and you set the max degree of parallelism (MAXDOP) option to a value of greater than 1. However, when you execute a parallel query that contains MERGE statements on clustered columnstore indexed tables through the MARS connection, you receive the following error message:

error 35377: When MARS is on, accessing clustered columnstore indexes is not allowed.

Note This issue does not occur when you set MAXDOP to 1.


The issue was first fixed in the following SQL Server cumulative updates: 

About cumulative updates for SQL Server


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

Article ID: 3055646 - Last Review: Jun 22, 2015 - Revision: 1