How to indicate what will be measured with a NONCLUSTERED COLUMNSTORE INDEX? I am new to columnstore INDEXes.  But I am fairly sure I need one now.
Here is my setup.  I have a table that has the columns ApplicationId, GroupId and TimeInMilliseconds.
I am going to want to run queries like what is the average time for a given ApplicationId or what is the total time for a given ApplicationId and GroupId.
My column store INDEX looks like this:
 Create NONCLUSTERED COLUMNSTORE INDEX CsIdx_PerformanceData 
 ON perf.PerformanceData
 (TimeInMilliseconds, ApplicationId, PerformanceGroupId, PerformanceSubGroupId)  
 

But I am confused on what this is saying.  It seems there is no distinction between dimensions and measures here.
Meaning, it seems like I could really be wanting to get the SUM of ApplicationIds when TimeInMilliseconds is 200 (which makes no sense at all).
Question
How do I set this up so that I can do the math on TimeInMilliseconds using the other columns?  (Or am I confusing the issue here?  Do I need a cube for what I am thinking?)
It is not necessary to distinguish between measures and dimensions when defining your columnstore. All columns are stored in the same manner. All columns included in any query should be in the columnstore, in most cases it is best to put every column in the table into the columnstore.