I'm trying to refactor (actually, rewrite) an application which currently uses only stored procedures to access the database (hundreds of SPs). My goal is to use Nhibernate and follow a good design as much as possible.But since the database (and the SPs) are used by dozens of other apps, I can't really change the db design. And off course, it's awful.I'm facing a design problem and I can't really find a good solution.I have a table called movies which contains movies, but these movies can be different things. For example, this table contains movies as well as episodes of tv shows and the only way to know the difference is a field named episode which is set to 0 for movies and 1 for episodes.My objective is to expose the following class hierarchy :public abstract class Program {}public class Episode : Program {}public class Movie : Program {}Currently, I have mapped the whole movies table to a model class MoviesModel and then I build my Episode/Movie class through AutoMapper and a factory method in the Program class :public static Program Load(MoviesModel movieModel)    {        if (movieModel.Episode > 0)            return Mapper.Map<Episode>(movieModel);        return Mapper.Map<Movie>(movieModel);    }This seems really wrong on many levels : I have an anemic data model since my MoviesModel is totally empty of any business logic, the automapper stuff becomes really hard to maintain when I add many other entities with relations to Movies, and I break the lazy loading with AutoMapper.I heard about the any mapping of nhibernate but it doesn't really solve my issue, it just creates sub components of a class.So my questions are :Ideally, where should be my business logic ? I guess in the MoviesModel class but I don't really like the idea to expose my database fields.Is there a way with nhibernate to map the same table in different classes based on a field value ?Is there a point to wrap the nhibernate objects if I want to provide a clean public API ?My goal is to build a base library which will be used (hopefully) on other legacy apps so I want to provide a clean API with logical methods and without exposing the database mess even if I still have to deal with it.Thanks for any help to put me in the right direction.
NHibernate and complex domain model against a legacy database
database;domain driven design;orm;domain model;nhibernate