title: How to substitute NULL with value in Power BI when joining one to many
body: <p>In my model I have table <code>AssignedToUser</code> that don't contain any NULL values. 
  Table <code>TotalCounts</code> contains number of tasks for each User.</p>
  
  <p>Those two table joined on UserGUID, and  table TotalCounts contains NULL value for UserGUID. </p>
  
  <p><a href="https://i.stack.imgur.com/ptLGQ.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/ptLGQ.png" alt="enter image description here"></a></p>
  
  <p>When I drop everything in one table there is NULL value for <code>AssignedToUser</code>.
  How can I substitute value NULL for AssignedToUser for "POOL".</p>
  
  <p><a href="https://i.stack.imgur.com/aK5Ta.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/aK5Ta.png" alt="enter image description here"></a></p>
  
  <p>Under EditQuery I tried to Create additional column </p>
  
  <pre><code>if [AssignedToUser] = null then "POOL" else [AssignedToUser]
  </code></pre>
  
  <p>But that didnt help. </p>
  
  <p>UPDATE:
  Thanks Alexis.
  I have created FullAssignedToUsers table, but when I try to make a relationship with TotalCounts on UserGUID - it doesnt like it. </p>
  
  <p><a href="https://i.stack.imgur.com/knnbD.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/knnbD.png" alt="enter image description here"></a></p>
  
  <p>Data in new a table looks like this:</p>
  
  <p><a href="https://i.stack.imgur.com/7kFAf.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/7kFAf.png" alt="enter image description here"></a></p>
  
  <p>UPDATE:
  File .ipbx can be accessed  here:</p>
  
  <p><a href="https://www.dropbox.com/s/95frggpaq6tce7q/User%20Open%20Closed%20Tasks%20Experiment.pbix?dl=0" rel="nofollow noreferrer">https://www.dropbox.com/s/95frggpaq6tce7q/User%20Open%20Closed%20Tasks%20Experiment.pbix?dl=0</a></p>