title: sum group by in MDX
body: <p>I want the equivalent SUM and Group By as in t-SQL. But I haven't found the answer on the web. 
  My MDX return has some records that have the same name. I want to show the distinct name with the measure summed up just like Group by feature in SQL. </p>
  
  <p>It seems like it's a common feature. Thanks.</p>