title: Remove duplicates in Tableau
body: <p>I am trying to remove duplicates from the ID field, I would like it so that only the earliest retention academic period is associated with the unique ID. For example:</p>
  
  <pre><code>Status | ID | Profile Period | Retention Period | Academic Period 
  
  Retained | 654321 | 200610 | 200620 | 200620
  
  Retained | 654321 | 200610 | 200710 | 200710
  
  Retained | 654321 | 200610 | 200720 | 200720
  
  CODO IN | 123456 | 200510 | 200520 | 200520
  
  CODO IN | 123456 | 200510 | 200610 | 200610
  
  CODO IN | 123456 | 200510 | 200620 | 200620
  </code></pre>
  
  <p>So what I want is to keep the repeated terms for Retained IDs, however, I want to the repeated CODO In values to take the earliest retention period:</p>
  
  <pre><code>Retained | 654321 | 200610 | 200620 | 200620
  
  Retained | 654321 | 200610 | 200710 | 200710
  
  Retained | 654321 | 200610 | 200720 | 200720
  
  CODO IN | 234567 | 200510 | 200520 | 200520
  </code></pre>
  
  <p>I have tried {Fixed [ID]: MIN [Retention Period]} but it doesn't seem to remove all the repeats for CODO In (i.e. I still see the counts for 200610 and 200620). </p>
  
  <p>Any suggestions on how to approach this task?</p>