NHibernate selecting from a many to many collection - nhibernate

Question

I would like NHibernate to generate the following SQL but I'm stuggling with the code below
SELECT rt.Id
FROM ClientContact cc
JOIN ClientContact_DefaultRequest d on d.ClientContactID = cc.Id
JOIN RequestType rt on d.RequestTypeId = rt.Id
WHERE
cc.Id = ContactId
public class GetDefaultRequestsForContact : SimpleQuery<IEnumerable<RequestType>>, IGetDefaultRequestsForContact
{
public int ContactId { private get; set; }
public GetDefaultRequestsForContact(ISession session) : base(session) { }
public override IEnumerable<RequestType> Execute()
{
var x = Session.QueryOver<ClientContact>()
.Where(c => c.Id == ContactId)
.JoinQueryOver<RequestType>(c => c.DefaultRequests)
.Select(c => c.DefaultRequests)
.List();
return null;
}
}
The generated SQL is only selecting the parent id (which is the parameter) I want all the child Ids.
SELECT this_.Id as y0_
FROM ClientContact this_
inner join ClientContact_DefaultRequest defaultreq3_
on this_.Id = defaultreq3_.ClientContactID
inner join RequestType requesttyp1_
on defaultreq3_.RequestTypeID = requesttyp1_.Id
WHERE this_.Id = 313706 /* #p0 */
This works but it is not strongly typed (HQL).
var x = Session.CreateQuery("SELECT R.Id FROM ClientContact cc JOIN cc.DefaultRequests R WHERE cc.Id = :contactId")
.SetParameter("contactId",ContactId)
.List<int>();
return x;

Answer 1

Try using Aliases like:
ClientContact Cont = null;
RequestType Req = null;
var x = session.QueryOver<ClientContact>(() => Cont)
.Where(() => Cont.ID == ContactId)
.JoinAlias(() => Cont.DefaultRequests, ()=> Req, JoinType.LeftOuterJoin)
.Select(ignore => Req.Id) // <-- Select wants a parameter
.List<int>();

Answer 2

You have to turn it around. I believe Faber's answer will also work well. So you do not have to turn it around. (But you could.)
ClientContact cAlias = null;
var x = Session.QueryOver<RequestType>()
.JoinAlias(rt => rt.ClientContacts, () => cAlias)
.Where(() => cAlias.Id == ContactId)
.Select(rt => rt.Id) // not sure what you want returned here, Id or the object)
.List();