public partial class ivdbDb156978Context : IdentityDbContext<ApplicationUser>
{
    static ivdbDb156978Context()
    {
        Database.SetInitializer<ivdbDb156978Context>(null);
    }

    public ivdbDb156978Context()
        : base("Name=ivdbContext")
    {
    }


    public DbSet<Car> Cars { get; set; }

public class ApplicationUser : IdentityUser
{

}

protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
    base.OnModelCreating(modelBuilder);

    // your stuff here
}

protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
    modelBuilder.Entity<IdentityUserLogin>().HasKey<string>(l => l.UserId);
    modelBuilder.Entity<IdentityRole>().HasKey<string>(r => r.Id);
    modelBuilder.Entity<IdentityUserRole>().HasKey(r => new { r.RoleId, r.UserId });
}

protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
    modelBuilder.Entity<IdentityRole>().HasKey<string>(r => r.Id).Property(p => p.Name).IsRequired();
    modelBuilder.Entity<IdentityUserRole>().HasKey(r => new { r.RoleId, r.UserId });
    modelBuilder.Entity<IdentityUserLogin>().HasKey(u => new {u.UserId, u.LoginProvider, u.ProviderKey});
}

protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
  base.OnModelCreating(modelBuilder);
  // your stuff here
}

protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
  // base.OnModelCreating(modelBuilder);
  // your stuff here
}