title: Adventure Works Explanation
body: <p>I've been looking at Microsoft's Adventure Works 2012 database. I'd be very interested if there's any information explaining why the tables were created as they are. Some sort of schema overview I guess.</p>
  
  <p>For example: </p>
  
  <p>Why they chose to create a <code>BusinessEntity</code> table as a sort of base class for Person, Employee, etc.</p>
  
  <p>Most of the data is normalized so why they chose to put the <code>CountryRegionCode</code> field into the <code>StateProvince</code> table instead of an ID to a separate table.</p>
  
  <p>Anyway I'm very interested in learning more about the decisions that went into the databases design. Anyone know a resource that goes into this sort of thing?</p>