Order by collection count using ICriteria & NHibernate

Question

Using the standard NHibernate example of Cats and Kittens, how would I use ICriteria to sort Cats based on Kitten count? For example, I want to do something like:

ICriteria crit = Session.CreateCriteria(typeof(Cat));
return crit.Order(Order.Asc("**Kittens.Count**"));

Anyone know how to achieve this?

Answer 1

In HQL you can do it like this:

select cat
from Eg.Cat cat
join cat.Kittens kitten
group by cat
order by count(kitten) asc

Answer 2

See http://forum.hibernate.org/viewtopic.php?p=2401219

It's Java Hibernate but almost the same thing (Projection, AddOrder)