modelling our domain

We have four types in our domain model that we want to persist: users, blogs, blog posts, and comments. The arrows in this diagram indicate relationships between them: comments are made on blog posts, blog posts are made in a blog, and blogs, blog posts and comments all have authors:

For the purposes of this tutorial, we are going to focus in on the user, which consists of two main parts: the user itself, and the user profile: