title: Magento quick getResourceModel question
body: <p>What class (if any) is called with this line of code?</p>
  
  <pre><code>Mage::getResourceModel('sales/order_invoice_collection')
  </code></pre>
  
  <p>Essentially I"m trying to figure out what database table is accessed with this resource model and how I can tweak that.  Thanks!</p>