EF - Exercise 2

Create the following database model using Entity Framework and Code First:

erDiagram
  User ||--o{ RegularUser : "is a"
  User ||--o{ Staff : "is a"
  Author ||--o{ Book : has
  Book }o--|| Genre : "belongs to"
  Borrowing }o--|| Staff : "borrowed by"
  Borrowing }o--|| Book : lends
  Purchase }o--|| RegularUser : "made by"
  Purchase }o--|| Staff : "sold by"
  Purchase }o--|| Book : sold

  Author {
    int AuthorID PK
    string Name
    DatiTime Birthdate
  }

  Book {
    string ISBN PK
    string Title
    int PublicationYear
    int NrOfCopiesAvailable
  }

  Genre {
    int GenreID PK
    string Name
  }

  User {
    int UserID PK
    string Username
    string Email
  }

  Staff {
    int UserID PK
    string StaffNr
    string Department
  }

  RegularUser {
	  
    int UserID PK
    string CustomerNr
  }

  Borrowing {
    int BorrowingID PK
    DateTime ReturnBy
  }

  Purchase {
    int PurchaseID PK
    double Amount
  }

Notice, that the relationship between User, RegularUser and Staff is a Joined-Table Inheritance. Use Constraints, such as [Required] where you think it’s useful.

After you are done generating the database, verify the schema, for example by using DataGrip to generate a database from the current schema and compare it to the schema, given above.