{“INSERT语句与FOREIGN KEY约束冲突该语句已被终止。”}

Question

there is also a userstats table, I want a one to one relationship, but i'm getting the above error when I try and register a user.Thanks for the help!

User Table:

     public class User
        {
            [Key]
            public int ID { get; set; }

            public int UserStatsID { get; set; }
            public virtual UserStats UserStats { get; set; }

           }

Userstats Table

  [Key]
    public int ID { get; set; }

    public int UserID { get; set;}
    [Required]
    public User User { get; set; }        

RegisterDetailsController

[HttpPost]
    [ValidateAntiForgeryToken]
    public ActionResult Create(User user)
    {
        if (ModelState.IsValid)
        {
            db.Users.Add(user);
            db.SaveChanges();
            if (user.Gender == Gender.Male )
            {
                return RedirectToAction("RegisterMale", "RegisterStats", new {id = user.ID });
            }
            else
            {
                return RedirectToAction("RegisterFemale", "RegisterStats", new { id = user.ID });

            }
        }

        return View(user);
    }

Answer 1

You can't have a true 1:1 relationship enforced entirely through foreign keys, as the inserts have to be done one at a time and doing that would violate the constraint.

Instead, you will have to make the relationship 1:0. Do this by making UserStatsID an int? instead of an int .

Answer 2

The problem is that your table has a foreign key to the UserStats table. If the foreign key field is nullable then you can use int? and put a null there if no value is provided. Anyway, the problem is that you are trying to insert a record where the foreign key's value does not exist as a primary key in the referenced table. Make sure that whenever you assign a value to a foreign key, the referenced table has that key in a record.