Complex query in nHibernate using DetachedCriteria
- by paszczi
Hello!
I'm currently trying to move from hand-crafted hql to queries constructed via DetachedCriteria. I have and HQL:
from GenericObject genericObject
left join fetch genericObject.Positions positions
where (positions.Key.TrackedSourceID, positions.Key.PositionTimestamp) in
(select gp.Key.TrackedSourceID, max(gp.Key.PositionTimestamp)
from GenericPosition gp
group by gp.Key.TrackedSourceID)
Now using DetachedCriteria:
var subquery = DetachedCriteria
.For (typeof (GenericPosition), "gp")
.SetProjection (Projections.ProjectionList ()
.Add (Projections.Property ("gp.Key.TrackedSourceID"))
.Add (Projections.Max ("gp.Key.PositionTimestamp"))
.Add (Projections.GroupProperty ("gp.Key.TrackedSourceID"))
);
var criteriaQuery = DetachedCriteria
.For (typeof (GenericObject), "genericObject")
.CreateAlias ("genericObject.Positions", "positions")
.SetFetchMode ("genericObject.Positions", FetchMode.Eager)
.Add (Subqueries.In (??, subquery))
I don't know what to type instead of ?? to create expression like (positions.Key.TrackedSourceID, positions.Key.PositionTimestamp)
