title: Google Sheets - filter list excluding values from other list
body: <p>I have a big sheet <code>raw_data</code> which is automatically populated by a script every 5 minutes. As such I cannot add new columns with formulas but have to solve problems in single formulas.</p>
  
  <p>The challenge:</p>
  
  <p>I need to pull out a list of unique values from a column <code>O</code>. At the same time, I need to filter out a certain set of values in range <code>A55:A</code></p>
  
  <p>I have this formula to pull out the unique values:
  <code>=SORT(UNIQUE(raw_data!O2:O))</code></p>
  
  <p>I tried playing with match, but how do I "inverse" the result from the <code>match</code> as I'm actually looking to 
  <em>exclude</em> rather than <em>include</em>:
  <code>=SORT(UNIQUE(FILTER(raw_data!O2:O,IFERROR((Match(raw_data!O2:O,A75:A200,0))))))</code></p>
  
  <p>I tried adding a <code>NOT()</code> around the <code>Match()</code> but that then gave me a no results error.</p>
  
  <p>Anyone?</p>