How do you insert a complex object into the database?

Question

Let's say we have these three tables:

--Car--
ID
1
2

--Event-- 
ID   CarID   EventTypeID  DateTimeAdded
1    1       1            2014-04-28 12:00:00     

--EventType-- 
ID  Name
1   "Entry Created"
2   "Entry added to sales chart"
3   "Entry removed from sales chart"

Using Entity Framework (EF 5 in my case), how would one add a Car object to the database? I have tried a number of different ways to accomplish this, including the code below, but nothing has worked yet.

Car newCar = new Car(){ }

Event newEvent = new Event(){
   CarID = newCar.ID,
   EventTypeID = 2,
   DateTimeAdded = Datetime.Now;
}

newCar.Event.Add(newEvent);

context.Car.Add(newCar);
context.SaveChanges();

Any assistance would be greatly appreciated.

---

EDIT: The exception comes up in a try catch after context.SaveChanges() occurs. Here is the innerexception from the exception:

The INSERT statement conflicted with the FOREIGN KEY constraint "FK_Event_EventType". The conflict occurred in database "CarSystem", table "dbo.EventType", column 'ID'

Note: there is a relationship between all three of these tables, including Event and EventType. Could this be causing the issue? If so, I've got no idea how to fix it.

Answer 1

I found the problem: the FK relationship between two of the tables had an issue.

Answer 2

You may want to change the sequence of operations as follows:

context.Car.Add(newCar);
newCar.Event.Add(newEvent);

context.SaveChanges();

That way the INSERT call for the Car row (parent) will be issued before the INSERT call for the Event row (child), avoiding the foreign key error.