Symptoms
When you browse an unbalanced parent/child hierarchy in Microsoft SQL Server Analysis Services client tool (for example, Excel, SSDT, SSMS) with a non-admin role, all hierarchy members display a drilldown symbol, even if you are looking at leaf members with nothing to drill down.
Cause
Many SSAS client applications use the "Children_Cardinality" (childcount) property in order to determine whether a specific hierarchy member has child members and should display a drilldown symbol. A newly introduced SSAS 2012 performance improvement may generate wrong childcount estimates for parent/child hierarchy leaf members that do not belong to the lowest hierarchy level (unbalanced hierarchies).
Resolution
This issue was first fixed in the following cumulative update of SQL Server. This fix introduces a new "IgnoreDimensionSecurityForPCChildCount" property in the SSAS configuration file "msmdsrv.ini".
You now have the choice to either maintain the SSAS 2012 performance improvements (use default value of "0") or to restore correct childcount estimates and the improved hierarchy browsing behavior (use a value of "1").Cumulative update 4 for SQL Server 2017 Cumulative Update 6 for SQL Server 2016 SP1
Cumulative Update 2 for SQL Server 2014 SP1 Cumulative Update 6 for SQL Server 2014 Cumulative Update 4 for SQL Server 2012 SP2
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.