Symptoms
Assume that you have a parent-child dimension that uses unary operators in Microsoft SQL Server 2012 Analysis Services (SSAS 2012). When you execute an MDX query that contains a filter (sub query) and uses multiple members in the dimension, the value that is returned is the rollup value for all the children of all the members of the dimension hierarchy. However, the expected value is the aggregation of the members that is selected for the filter condition.
Resolution
The issue was first fixed in the following cumulative update of SQL Server.
Cumulative Update 3 for SQL Server 2012 SP2 /en-us/help/3002049
Cumulative Update 12 for SQL Server 2012 SP1 /en-us/help/2991533
About cumulative updates for SQL Server
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.