How to get the first date

I have a time dimention of Year, Month and Date
I want to know the unit sales of the first date of every month of every
store.
How can I implement the MDX?
look at this:
http://msdn.microsoft.com/library/de...l/semiadd2.asp
(Semi additive measures)
You are in the same case, except you want the start date instead-of the end
date in your calculations.
"ad" <ad@.wfes.tcc.edu.tw> a crit dans le message de news:
%23%23A33vNsEHA.3556@.TK2MSFTNGP10.phx.gbl...
>I have a time dimention of Year, Month and Date
> I want to know the unit sales of the first date of every month of every
> store.
> How can I implement the MDX?
>