Mapping a class with XML

The suggested first step in any new NHibernate application is mapping the model. The mapping describes how objects O should be retrieved and stored as relational data R in the database. In the simplest scenarios, this is merely a straightforward mapping between classes in the code and tables in the database. Still, the structure of the code or of the database will usually require careful mapping in order to get correct behavior and optimal performance.

Note

Most of the recipes in this chapter utilize a custom library called NH4CookbookHelpers, which makes it possible to visualize the results and behaviors of the mappings described. For convenience, we use NuGet to reference this library, but feel free to download the source code from https://github.com/gliljas/NH4CookbookHelpers if you want to modify its functionality or just see how it works.

Getting ready

Before we begin mapping, let's get our Visual Studio solution set up. Follow these steps to set up your solution...