Entity framework compatibility with oracle databases :

considering this segment of code :

Employee emp=new Employee{ name="EmpName",position="develoeper"};

Entities db=new Entities();

db.Employees.Add(emp);

db.SaveChanges();

int id=emp.Id;

//what's the value of id when using oracle database ??? is this value different when using sql server ?? how to work around this problem ??