Question

select p.Id, sum(inc.Quantity) 
from Products p join Incomes inc
group by p.Id 
order by sum(inc.Quantity) >0

This query gives NHibernate.Hql.Ast.ANTLR.QuerySyntaxException on ORDER BY clause. I wonder is it possible to overcome this error and perform sorting by some expression?

UPDATE
I need to sort products list by name, price etc. BUT products with quantity == 0 must go to the bottom of the list (no matter what name, price it has). Also I need to perform paging of that list.

Answer 1

You need a syntax that is supported by SQL too. This works:

select p.Id, sum(inc.Quantity) 
from Products p join p.Incomes inc
group by p.Id 
order by case when sum(inc.Quantity) > 0 then 0 else 1 end

Nitpicking: why do your entities have plural names?