title: Extend a model to add methods
body: <p>I have reverse engineered a MySQL database in a C# desktop app. What I would like to do is extend one of the model classes, so that I can add methods to it to use locally in my application. I don't want to change any properties  or anything just. Just get information and calculate things.</p>
  
  <p>The problem is that when I inherit from one of the model classes I get an error about a new discriminator field being in the class but not the database.</p>
  
  <p>Is there a way to do what I want to do?</p>