title: MySQL Help: How do I automatically update a column?
body: <p>I have a table called <code>cups</code> with the columns <code>item_num, product_name, amount, price, total</code>.</p>
  <p>I want to automatically update <code>total = amount * price</code> when I enter a new row with just the <code>item_num, product_name, amount, price</code>.</p>
  <p>How do I do this?</p>