title: Magento ORM Documentation
body: <p>Outside of the source code, is there any extensive documentation on the Magento ORM?  I get the basics, and can usually dig through the Mage code base, litter it with Mage::Log calls and figure out something that works, but my efficiency would go way up if I had a high level overview of how the models are <strong>intended</strong> to be used.  How do the aggregate methods work, what's the best way to join, when should you extend the models, when's the best time to use the eav models vs. the non-eav ones, etc.</p>
  
  <p>Something like the <a href="http://docs.djangoproject.com/en/dev/topics/db/models/" rel="noreferrer">Django Model Documentation</a>, but for Magento.</p>