Schema and Use Cases

Data model

To keep it simple, we’ll use the same data model we used earlier to define our schema.

We’ll keep all the attributes we had about the book example and add the ability to add some reviews. We’ll add a new entity called User to do that. Each user can leave one or more reviews on any book they want. Let’s consider the following updates to our class diagram, where we add the User type with only the firstName and lastName attributes.

SQL use case

Let’s try to split our data into two databases, one SQL and the other ...