Symptoms
Assume that you install the SQL Server Analysis Services (SSAS) in tabular mode on a server that is running Microsoft SQL Server 2014 or SQL Server 2012. After you divide a table into more than one logical part, and then you process the partitions, some data in the partitions is updated incorrectly. This causes tabular queries (DAX/MDX) to return corrupted or incorrect information. For example, some positive values in one or more table columns are changed to negative values.
Note This problem can occur in tabular partitions other than the partition that is being processed.
Resolution
The issue was first fixed in the following cumulative updates for SQL Server:
Cumulative Update 2 for SQL Server 2014 SP1
Cumulative Update 6 for SQL Server 2012 SP2
Cumulative Update 7 for SQL Server 2014
Each new cumulative update for SQL Server contains all the hotfixes and all the security fixes that were included with the previous cumulative update. Check out the latest cumulative updates for SQL Server:
Status
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
References
Learn about the terminology Microsoft uses to describe software updates.
