title: Power BI compare dates
body: <p>I am new with power BI and need your help.</p>
  
  <p>I have 3 columns which are: </p>
  
  <ol>
  <li>date1</li>
  <li>reviseDate</li>
  <li>Shipped_Date</li>
  </ol>
  
  <p>I need to compare column <code>reviseDate</code> to <code>shipped_date</code> if it is &lt;> or =.</p>
  
  <p>How to I do it, if <code>reviseDate</code> column is blank, must refer on column <code>Date1</code> to compare with <code>shipped_Date</code> column?</p>
  
  <p><a href="https://i.stack.imgur.com/6mHXf.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/6mHXf.png" alt="Desired output"></a></p>