title: SELECT all elements that don't exist in another table
body: <p>I have two tables, a USER table which contains all current users. The next table is called tasks and has a lot of information, one of the columns is PointPerson which is the same as one of the columns in the user table. This column has entries for people who are not users anymore. This is what I want to get from a SELECT statement. I want all of the users in the task table that don't exist on the user table.</p>
  
  <p>This is what I have tried but I am getting no responses which can't eb correct:</p>
  
  <pre><code>SELECT DISTINCT TSK.PointPerson FROM [Task] AS TSK
  WHERE NOT EXISTS (
  SELECT DisplayName FROM [User]
  )
  </code></pre>
  
  <p>What am I doing wrong and how do I get the desired result?</p>