title: Mixins vs. Citier in Ruby on Rails for inheritance
body: <p>I am facing a design problem that I cannot figure out at all. I have a table in my DB called Timed_Tests. Timed_Tests has an associated model called Timed_Test.</p>
  
  <p>Recently, I realized that I actually need three types of Timed_Test with slightly different features. There is current Timed_Test, there will be a Test_Basic without the end date that Timed_Test has, and there will be a Special_Test with a couple of additional attributes.</p>
  
  <p>I'm trying to figure out what the best way is to set this up. Should I have one large Tests table with all the different types of attributes for all the different types of Tests? How should I setup my class inheritance structure? Should I use citier (http://peterhamilton.github.com/citier/)? How do mixins fit in with DB schema...?</p>
  
  <p>I have asked a bunch of questions and they are a bit vague I know - please feel free to ask me clarifying questions, and feel free to answer any one of the issues I'm thinking about above.</p>
  
  <p>Thanks so much!</p>