title: MySQL ON DUPLICATE KEY UPDATE syntax error
body: <p>I was wondering if anyone can spot any mistakes in my sql statement. I would like it to insert a new record into my table if one doesn't exists already. If it does exist then just update it. My primary key in the date field.</p>
  <p>Here is my statement as it appears in php and also the error I'm getting:</p>
  <pre><code>INSERT INTO ExtraStats (date, supportStaff, startEmails, endEmails, emailsAnswered) VALUES ('$startDate', '$supportStaff', '$startEmail', '$endEmail', '$emailAnswered') ON DUPLICATE KEY UPDATE (supportStaff, startEmails, endEmails, emailsAnswered) VALUES ('$supportStaff', '$startEmail', '$endEmail', '$emailAnswered')
  
  You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '(supportStaff, startEmails, endEmails, emailsAnswered) VALUES ('2', '3', '1', '3' at line 1 
  </code></pre>