title: Unique values for combination of columns in Hybris Impex Files
body: <p>I'm creating a Hybris impex file to import into my Database. </p>
  
  <p>I want to perform an INSERT_UPDATE action with the data from the file, so I need to tell Hybris which column(s) need to be unique, so that it knows when to update a record instead of insert it.</p>
  
  <p>I know that to tell Hybris that a certain column needs to be unique I can add the unique attribute to that column, like this:</p>
  
  <pre><code>INSERT_UPDATE SLEmployee;Firstname[unique=true, required=true];Lastname[required=true];Function;
  </code></pre>
  
  <p>But on my example above, how do I tell Hybris that the combination of the columns Firstname + Lastname must be unique?</p>