NHibernate Criteria SQL Inner Join on Sub Select Same Table - sql-server

Question

I can't for the life of me figure out how to translate the following SQL query using NHibernate's Criteria API:
SELECT r.* from ContentItemVersionRecords as r
INNER JOIN (
SELECT ContentItemId as CID, Max(Number) as [Version]
FROM ContentItemVersionRecords
GROUP BY ContentItemId
) AS l
ON r.ContentItemId = l.CID and r.Number = l.[Version]
WHERE Latest = 0 and Published = 0
The table looks like this:
The result of the SQL query above will return the highlighted records.
The idea is to select the latest version of content items, so I basically need to group by ContentItemId and get the record with the highest Number.
So the result will look like this:
I started out with a detached criteria, but I am clueless as to how to use it in the criteria:
// Sub select for the inner join:
var innerJoin = DetachedCriteria.For<ContentItemVersionRecord>()
.SetProjection(Projections.ProjectionList()
.Add(Projections.GroupProperty("ContentItemId"), "CID")
.Add(Projections.Max("Number"), "Version"));
// What next?
var criteria = session.CreateCriteria<ContentItemVersionRecord>();
Please note that I have to use the Criteria API - I can't use LINQ, HQL or SQL.
Is this at all possible with the Criteria API?
UPDATE: I just came across this post which looks very similar to my question. However, when I apply that as follows:
var criteria = session
.CreateCriteria<ContentItemVersionRecord>()
.SetProjection(
Projections.ProjectionList()
.Add(Projections.GroupProperty("ContentItemId"))
.Add(Projections.Max("Number")))
.SetResultTransformer(Transformers.AliasToBean<ContentItemVersionRecord>());
I get 2 results, which looks promising, but all of the integer properties are 0:
UPDATE 2: I found out that if I supply aliases, it will work (meaning I will get a list of ContentItemVersionRecords with populated objects):
var criteria = session
.CreateCriteria<ContentItemVersionRecord>()
.SetProjection(
Projections.ProjectionList()
.Add(Projections.Max("Id"), "Id")
.Add(Projections.GroupProperty("ContentItemId"), "ContentItemId")
.Add(Projections.Max("Number"), "Number"))
.SetResultTransformer(Transformers.AliasToBean<ContentItemVersionRecord>());
However, I can't use the projected values as the end result - I need to use these results as some sort of input into the outer query, e.g.
SELECT * FROM ContentItemVersionRecord WHERE Id IN ('list of record ids as a result from the projection / subquery / inner join')
But that won't work, since the projection returns 3 scalar values (Id, ContentItemId and Number). If it would just return "Id", then it might work. But I need the other two projections to group by ContentItemId and order by Max("Number").

Answer 1

OK, so in a nutshell, you need to unwind that nested query, and do a group by with a having clause, which is pretty much a where on aggregated values, as in the following HQL:
SELECT civ.ContentItem.Id, MAX(civ.Number) AS VersionNumber
FROM ContentItemVersionRecord civ
JOIN ContentItem ci
GROUP BY civ.ContentItem.Id " +
HAVING MAX(civ.Latest) = 0 AND MAX(civ.Published) = 0
This gives you, for each deleted content items (those have all their latest and published flags to zero on all their content item version records), the maximum version number, i.e. the latest version of each deleted content item.