Pass data from Shopify URL to saved order : <p>What is a method of passing custom data through a Shopify URL and having that data stored with the order (for later extraction through reports, admin access, API pull, etc.)?</p>

<p>For example, I would like to produce URLs like </p>

<blockquote>
  <p>examplestore.com/products/soccerball?aff=123456</p>
</blockquote>

<p>(for an external affiliate tracking system), and have that <strong>123456</strong> be saved with the order.  Then I could pull the orders from Shopify and know which orders were associated with which affiliates.</p>

<p>I realize there are affiliate apps for use within Shopify, but they seem to want to own the affiliate definition and data.  This isn't what I need, as the IDs I pass in are entirely owned and managed by an external system.</p>
