title: How to write a CASE statement in DAX to return with a table expression
body: <p>I have a <code>DAX</code> statement, something like:</p>
  
  <pre><code>EVALUATE
  
  SUMMARIZECOLUMNS (
     TableName[FieldName1]
    ,TableName[FieldName2]
  //I want to include a CASE statement here for my third column
  )
  </code></pre>
  
  <p>With the behavior of <code>SUMMARIZE</code> and <code>SUMMARIZECOLUMNS</code>, I get errors when trying to use a CASE like statement here with either <code>SWITCH</code> or <code>IF</code>, which I assume is because of the way <code>SUMMARIZE</code> groups by. Unless you use an aggregate in the <code>SUMMARIZE</code>, there doesn't seem to be a simple way to include a derived column from a <code>CASE statement</code> in the output of <code>SUMMARIZE</code>. Has anyone worked through this problem?</p>