title: Conditional isn't working
body: <p>Spent an hour already searching and trying to get this work. Starting to hate mysql.
  What am I doing wrong here?</p>
  
  <pre><code>UPDATE product_reward pr
    LEFT JOIN product p ON (pr.product_id = p.product_id)
    LEFT JOIN product_special ps ON (pr.product_id = ps.product_id)
  
  SELECT CASE ps.price  
    WHEN NULL
      THEN SET pr.points = ROUND(p.price * 1);
    ELSE 
      SET pr.points = ROUND(ps.price * 1);
  END;
  </code></pre>
  
  <p>I tried using normal <code>IF ELSE</code>, but apparently that only works inside of procedures.
  I'm trying to set points based on normal price only if special price is <code>NULL</code>.</p>