title: Counting Distinct Across Multiple Columns (Vertica SQL)
body: <p>Checked other questions without getting a clear answer.  I saw a simple answer using MySQL, but it doesn't work in Vertica.  Is there an efficient way to count distinct in vertica SQL across multiple columns.</p>
  
  <p>For example, I know in MySQL you can do something like this:</p>
  
  <pre><code>SELECT l.computer, l.user, COUNT(DISTINCT l.computer, l.user) AS count
  FROM login l 
  GROUP BY l.computer, l.user
  </code></pre>
  
  <p>Is there a similar syntax in vertica?</p>
  
  <p>Thanks,
  Ben</p>