title: Magento: Include Configurable Product Sku on Invoice - Currently Associated Simple Product Only Shown
body: <p>I need to include the Configurable Product SKU on all print invoices as the configurable product SKU is human readable but the simple products are 16 digit numerical barcodes which makes for picking products a nightmare.</p>
  
  <p>I've found /app/code/core/Mage/Sales/Model/Order/Pdf/Invoice.php which writes the document. In it, it has the following which I believe creates the file.</p>
  
  <pre><code>    $page-&gt;drawText(Mage::helper('sales')-&gt;__('Product'), 35, $this-&gt;y, 'UTF-8');
      $page-&gt;drawText(Mage::helper('sales')-&gt;__('SKU'), 255, $this-&gt;y, 'UTF-8');
      $page-&gt;drawText(Mage::helper('sales')-&gt;__('Price'), 380, $this-&gt;y, 'UTF-8');
      $page-&gt;drawText(Mage::helper('sales')-&gt;__('Qty'), 430, $this-&gt;y, 'UTF-8');
      $page-&gt;drawText(Mage::helper('sales')-&gt;__('Tax'), 480, $this-&gt;y, 'UTF-8');
      $page-&gt;drawText(Mage::helper('sales')-&gt;__('Subtotal'), 535, $this-&gt;y, 'UTF-8');
  </code></pre>
  
  <p>My question is how can I change 'SKU' to be the configurable product SKU. All products in my store are configurable so it's not an issue it overrides the simple product sku.</p>
  
  <p>Thanks.</p>