Question

problem is with foreign key:

The INSERT statement conflicted with the FOREIGN KEY constraint “FK_uzytkownik_Logowanie”. The conflict occurred in database
“Restauracja”, table “dbo.Logowanie”, column ‘LoginID’.
The statement has been terminated.

I check this using breakpoints, and primary key in Logowanie table was added when breakpoints (running application) was after

baza.SubmitChanges();

Primary key of LoginID in logowanie table is added automatically during SubmitChanges.

How to copy value of LoginID from logowanie table to LoginID in uztkownik table? I add foreign key value here, but here LoginID hasn’t value yet.

Logowanie newlog = new Logowanie()
{
   Login = model.LoginModel.Użytkownik,
   Haslo = model.LoginModel.Hasło,
   konto = model.LoginModel.Konto
};

uzytkownik user = new uzytkownik()
{
   imie = model.uzytkownikModle.imie,
   nazwisko = model.uzytkownikModle.nazwisko,
   pesel = model.uzytkownikModle.pesel,
   nip = model.uzytkownikModle.nip,
   telefon = model.uzytkownikModle.telefon,
   adres_zamieszkania = model.uzytkownikModle.adres_zamieszkania,
   email = model.uzytkownikModle.email,
   LoginID = newlog.LoginID //<<<----------------
};

baza.Logowanies.InsertOnSubmit(newlog);
baza.uzytkowniks.InsertOnSubmit(user);

baza.SubmitChanges();

Answer 1

uzytkownik should have a property called Logowanie, which you can set to the new instance you created but didn’t Submit yet:

user.Logowanie = newlog;