I want to reduce roundtrips to database when I add relationship.
public class Parent { public virtual int Id { get; set; } public virtual string Name { get; set; } public virtual IList Children { get; set; } //inverse = true; cascade = all } public class Child { public virtual int Id { get; set; } public virtual string Name { get; set; } public virtual Parent Parent { get; set; } } Child child = Session.Get(1); Parent parent = Session.Load(1); child.Parent = parent; Session.Flush();
It works, I have only select for child and update for child. But it doesn't work with second level cache.
=== Session 1 === Parent parent = Session.Get(1); var count = parent.Children.Count; === Session 1 === === Session 2 === Child child = Session.Get(1); Parent parent = Session.Load(1); child.Parent = parent; Session.Flush(); === Session 2 === === Session 3 === Parent parent = Session.Get(1); var count = parent.Children.Count; //INCORRECT! Session 2 didn't update collection. === Session 3 ===
If I add parent.Children.Add(child) in Session 2, NHibernate do select for parent, but why? I think it's overhead.