saving reference using ServiceStack ORMLite - orm

Question

I am using ORMLite as my ORM and I am using it with following structure which contains the foreign key relation ship:
public class Order
{
[AutoIncrement]
public int Id { get; set; }
[Reference]
public Item Item { get; set; }
public string ProUserId { get; set; }
public string Details { get; set; }
}
public class Item
{
[AutoIncrement]
public int Id { get; set; }
public string Description { get; set; }
}
As we can see that Order contains the reference to the Item. In DB Order table has a foreign key called ItemId in the table and I have annotated that key in the design view with [Reference] attribute.
I am trying to save the Order with following code:
var order = new Order
{
Item = new Item
{
Id = 3,
Description = "Something"
},
ProUserId = "kunal#kunal.com",
Details = "fdfsdfsd"
};
Db.Save(order,references:true);
I was hoping that ORMLite would pick up the relationship and with ItemID in the Order table but it did not and it did throw following error instead:
Cannot insert the value NULL into column 'ItemId', table 'WebApp.dbo.Order'; column does not allow nulls. INSERT fails.
I tried changing my schema and addred OrderId column in my Item table with reference there and that works fine. But that is not the correct design. Should I make any changes in my code/schema to support this feature?

Answer 1

You still need to provide the foreign key that OrmLite can use to store the relationship, e.g. either on the Child/ForeignKey table:
public class Order
{
[AutoIncrement]
public int Id { get; set; }
[Reference]
public Item Item { get; set; }
public string ProUserId { get; set; }
public string Details { get; set; }
}
public class Item
{
[AutoIncrement]
public int Id { get; set; }
public int OrderId { get; set; } //Parent Table PK
public string Description { get; set; }
}
Or for 1:1 relationships, can be on the Parent table, e.g:
public class Order
{
[AutoIncrement]
public int Id { get; set; }
[Reference]
public Item Item { get; set; }
public int ItemId { get; set; } //Child Table PK
public string ProUserId { get; set; }
public string Details { get; set; }
}
public class Item
{
[AutoIncrement]
public int Id { get; set; }
public string Description { get; set; }
}