Entity framework, code first generation relationship between tables - sql-server

Question

I'm learning EF with MVC and following
video
They saying that line :
public ICollection<Chirp> Chirps { get; set; }
adds the relationship between the two models, but I don't see any difference so far when looking at both tables columns and keys after regenerating tables WITHOUT this line. I'm missing something as this kind of relationship is mentioned in all the tutorials.
public class User
{
public int Id { get; set; }
public String Name { get; set; }
public ICollection<Chirp> Chirps { get; set; }
}
public class Chirp
{
public int Id { get; set; }
public string Message { get; set; }
public User User { get; set; }
}
public class MyContext : DbContext
{
public DbSet<Chirp> Chirps { get; set; }
public DbSet<User> Users { get; set; }
}
In other words, does public ICollection Chirps { get; set; } tell EF to do anything with db structure ?
Thank you!

Answer 1

This should be generating an additional table that tracks the User to Chirps relationship. Look in your database for a User_Chirps or UserChirps table that should have two columns, User_Id and Chirp_Id. Additionally, I just noticed that your id property is using a lowercase i for id. I believe that the conventions in Entity Framework are expecting a property name of Id with an uppercase I. So you may want to try changing that as well.

Answer 2

Seems that difference is in constraint of the Chirps table. Without public ICollection Chirps { get; set; }
its:
ALTER TABLE [dbo].[Chirps] WITH CHECK ADD CONSTRAINT **[Chirp_User]** FOREIGN KEY([User_id])
REFERENCES [dbo].[Users] ([id])
while with it its :
ALTER TABLE [dbo].[Chirps] WITH CHECK ADD CONSTRAINT **[User_Chirps]** FOREIGN KEY([User_id])
REFERENCES [dbo].[Users] ([id]