public class ApplicationUser

{

    public string Id { get; set; }

    public string Name { get; set; }

    public ICollection<Gig> Gigs { get; set; }

    public ICollection<Attendance> Attendances { get; set; }

}

​

public class Genre

{

    public byte Id { get; set; }

    public string Name { get; set; }

}

​

public class Gig

{

    public int Id { get; set; }

    [Required]

    public ApplicationUser Artist { get; set; }

    [Required]

    public string ArtistId { get; set; }

    public DateTime DateTime { get; set; }

    [Required]

    [StringLength(255)]

    public string Venue { get; set; }

    [Required]

    public Genre Genre { get; set; }

    [Required]

    public byte GenreId { get; set; }

    public ICollection<Attendance> Attendances { get; set; }

}

​

public class Attendance

{

    public int GigId { get; set; }

    public string AttendeeId { get; set; }

    public Gig Gig { get; set; }

    public ApplicationUser Attendee { get; set; }

}

​

public class MyDbContext : DbContext

{

    public DbSet<ApplicationUser> ApplicationUsers { get; set; }

    public DbSet<Genre> Genres { get; set; }

    public DbSet<Gig> Gigs { get; set; }

    public DbSet<Attendance> Attendances { get; set; }

    protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)

    {

        // Visual Studio 2015 | Use the LocalDb 12 instance created by Visual Studio

        optionsBuilder.UseSqlServer(@"Server=(localdb)\mssqllocaldb;Database=EF7Test.MyDbContext;Trusted_Connection=True;");

        // Visual Studio 2013 | Use the LocalDb 11 instance created by Visual Studio

        // optionsBuilder.UseSqlServer(@"Server=(localdb)\v11.0;Database=EFGetStarted.ConsoleApp.NewDb;Trusted_Connection=True;");

    }

    protected override void OnModelCreating(ModelBuilder modelBuilder)

    {

        modelBuilder.Entity<Attendance>().HasKey(e => new { e.GigId, e.AttendeeId });

        modelBuilder.Entity<Attendance>().HasOne(e => e.Attendee).WithMany(e => e.Attendances).HasForeignKey(e => e.AttendeeId).OnDelete(DeleteBehavior.Restrict);

        modelBuilder.Entity<Attendance>().HasOne(e => e.Gig).WithMany(e => e.Attendances).HasForeignKey(e => e.GigId);

        modelBuilder.Entity<Gig>().HasOne(e => e.Artist).WithMany(e => e.Gigs).HasForeignKey(e => e.ArtistId);

        base.OnModelCreating(modelBuilder);

    }

}

​