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How to factorize a Linq request with multiple includes?

I want to simplify a linq Query that contains multiple includes.
My model is simple: a site is linked to one contract, that is linked to one client. On that client I need to get with a single request the telephones, mails and honorifics (appelRef).
I want a single request because behind the request is translated by entity framework into a SQL Server request.
Here is the linq request:
var search =
from IMT.Site s in imtContext.IMTObjects.OfType<IMT.Site>()
.Include(
s => s.LienContratSiteRef
.Select(l => l.Contrat)
.Select(c => c.LienContratClientRef
.Select(l => l.Client)
.Select(cl => cl.Telephones ) ) )
.Include(s => s.LienContratSiteRef
.Select(l => l.Contrat)
.Select(c => c.LienContratClientRef
.Select(l => l.Client)
.Select(cl => cl.Mails ) ) )
.Include(s => s.LienContratSiteRef
.Select(l => l.Contrat)
.Select(c => c.LienContratClientRef
.Select(l => l.Client)
.Select(cl => cl.AppelRef ) ) )
where s.Reference.ToString() == siteId
select s;
Yor can notice the block
.Include(
s => s.LienContratSiteRef
.Select(l => l.Contrat)
.Select(c => c.LienContratClientRef
.Select(l => l.Client)
..is repeated three time. Is ther a way to factorize that code block ?
Update: there are intermedray objects LienContratSiteRef and LienContratClientRef and relationships are 0 - *, so that LienContratSiteRef.Contrat and LienContratClientRef.Client are collections.
I also tried:
.Include(
s => s.LienContratSiteRef
.Select(l => l.Contrat)
.Select(c => c.LienContratClientRef
.Select(l => l.Client)
.Select(cl => new { Tels = cl.Telephones, Mail = cl.Mails, Appel = cl.AppelRef} ) ) )
but It results with a runtime error:
The Include path expression must refer to a navigation property
defined on the type.

The s => ... inside the include could be refactored into a delegate, then just .Include that delegate multiple times.
It looks like the signature would be Func<Site, IEnumerable<Client>>?
E.g.
static IEnumerable<Client> Foo(Site site) => site.LienContratSiteRef
.Select(l => l.Contrat)
.Select(c => c.LienContratClientRef
.Select(l => l.Client)

String-based Chaining
The Include() method supports a dot-delimited string parameter which can be used to pull an complete graph of objects down as opposed to making multiple chained select calls:
.Include("LienContratSiteRif.Contrat.LienContratClientRef.Client")
From there, if you wanted to include multiple additional properties, I believe that you could have another include for those sub properties:
.Include("LienContratSiteRif.Contrat.LienContratClientRef.Client, Client.Telephones, ...")
Lambda-based Chaining
You should be able to accomplish something similar by chaining your lambda-based includes into a single Include() call as well using:
.Include(c => LienContratSiteRif.Contrat.LienContratClientRef.Client)

It looks like you're trying to make an entity framework projection!
A project allows you to select only the properties that you want to return. (just like a SQL Select)
To use a projection, your code should roughly look like this:
var search = imtContext.IMTObjects.OfType<IMT.Site>()
.Where(s => s.Reference.ToString() == siteId)
.Select(s => new {
Telephones = s.LienContratSiteRef.Contrat.Select(c => c.LienContratClientRef.Client.Select(cli => cli.Telephones),
Mails = s.LienContratSiteRef.Contrat.Select(c => c.LienContratClientRef.Client.Select(cli => cli.Mails),
AppelRef = s.LienContratSiteRef.Contrat.Select(c => c.LienContratClientRef.Client.Select(cli => cli.AppelRef)
}).ToList();
If Telephones, Mails, AppelRefare also collections, then you can do aggregate the collections together like this in memory after the query has been run:
var telephones = search.SelectMany(x => x.Telephones).ToList();
var mails = search.SelectMany(x => x.Mails).ToList();
var appelRefs = search.SelectMany(x => x.AppelRef).ToList();

NHibernate QueryOver and string.format

I am working with QueryOver in NHibernate and I want to customize one property of my projected DTO using the following syntax:
IEnumerable<PersonResponseMessage> persons =
session.QueryOver<PersonEntity>()
.SelectList(list => list
.Select(p => p.Active).WithAlias(() => dto.Active)
.Select(p => p.Alert).WithAlias(() => dto.Alert)
.Select(p => p.Comments).WithAlias(() => dto.Comments)
.Select(p => string.Format("{0}api/Person/{1}", uriHelper.Root, p.Id)).WithAlias(() => dto.DetailsUrl)
)
.TransformUsing(Transformers.AliasToBean<PersonResponseMessage>())
.List<PersonResponseMessage>();
Unfortunately NHibernate cannot do this and throws an exception saying that:
Variable P referenced from scope "" is not defined

There are in common two ways. Partially we can move that concat operation on the DB side, as documented here:
16.7. Projection Functions
In this case, we'll use the Projections.Concat:
.SelectList(list => list
.Select(p => p.Active).WithAlias(() => dto.Active)
.Select(p => p.Alert).WithAlias(() => dto.Alert)
.Select(p => p.Comments).WithAlias(() => dto.Comments)
// instead of this
//.Select(p => string.Format("{0}api/Person/{1}", uriHelper.Root, p.Id))
// .WithAlias(() => dto.DetailsUrl)
// use this
.Select(p => Projections.Concat(uriHelper.Root, Projections.Concat, p.Id))
.WithAlias(() => dto.DetailsUrl)
)
.TransformUsing(Transformers.AliasToBean<PersonResponseMessage>())
.List<PersonResponseMessage>();
But I would vote for ex-post processing on the Application tier, in C#:
.SelectList(list => list
.Select(p => p.Active).WithAlias(() => dto.Active)
.Select(p => p.Alert).WithAlias(() => dto.Alert)
.Select(p => p.Comments).WithAlias(() => dto.Comments)
// just the ID
.Select(p => p.Id).WithAlias(() => dto.Id)
)
.TransformUsing(Transformers.AliasToBean<PersonResponseMessage>())
.List<PersonResponseMessage>()
// do the concat here, once the data are transformed and in memory
.Select(result =>
{
result.DetailsUrl = string.Format("{0}api/Person/{1}", uriHelper.Root, p.Id)
return result;
});

Linq - where inside include

I know that this won't work as written, but I'm struggling to see the right answer, and this non-functional code hopefully illustrates what I'm trying to achieve:
var defaults = _cilQueryContext.DefaultCharges
.Where(dc => dc.ChargingSchedule_RowId == cs.RowId);
List<DevelopmentType> devTypes =
defaults.Select(dc => dc.DevelopmentType)
.Include(d => d.DefaultCharges)
.Include(d => d.OverrideCharges.Where(oc => oc.ChargingSchedule_RowId == cs.RowId))
.Include(d => d.OverrideCharges.Select(o => o.Zone))
.ToList();
Essentially, I had presumed this required a join, but seeing as I'm trying to select a parent object containing two related types of children, I can't see what would go in the join's "select new" clause.

As far as I am aware Include does not support this type of sub-querying. Your best option is to use projection e.g.
List<DevelopmentType> devTypes =
defaults.Include(x => x.DefaultCharges)
.Include(x => x.OverrideCharges)
.Select(x => new {
DevType = x.DevelopmentType,
Zones = x.OverrideCharges.Where(oc => oc.ChargingSchedule_RowId == cs.RowId)
.Select(oc => oc.Zone).ToList()
})
.Select(x => x.DevType)
.ToList();

Joins in nhibernate

I am using blow code for join in nhibernate, which is working fine. But i don't wants to use .List on both queries before join, i wants to use .List after join. I don't know nhibernate too much.. please provide me help that what i should make changes in below funciton to first join the data and then apply .List over it.
public IEnumerable<PGrp> GetSol()
{
_pGrpR = null;
_pGrp = null;
QueryOver<Phy, Phy> activePhyQuery = GetDataQuery();
var phyGrpR = _session.QueryOver(() => _pGrpR)
.Where(
Subqueries.WhereProperty<PGrpR>(p => _pGrpR.PhyId).In(
activePhyQuery))
.List<PGrpR>();
IList<PGrp> pGrps = _session.QueryOver(() => _pGrp)
.Where(x => !x.AC)
.List<PGrp>();
var newPGrps = pGrps
.Join(
pGrpR,
p => p.Id,
x => x.PGrpId,
(p, x) => p
).Distinct().OrderBy(x => x.Name);
return newPGrps;
}
Thanks

PGrpR pGrpR = null;
IList<PGrp> pGrps = _session.QueryOver(() => _pGrp)
.Where(x => !x.AC)
.JoinAlias(pgrps => pgrps.pGrpR, () => pGrpR) // Set real property name
.OrderBy(() => pGrpR.Name).Asc
.Select(Projections.Distinct(Projections.Property(() => pGrpR."PropertyForDistinct")))
.TransformUsing(Transformers.DistinctRootEntity)
.List<PGrp>();

Subquery parent id in NHibernate QueryOver

I'm trying to understand how this may work.
What I would have is to have all Trees from a given list of IDs that has not rotten apples.
Looks easy but I'm fresh of NHibernate, not so good in SQL and as you can see I'm stuck.
I wrote this code down here:
Tree treeitem = null;
QueryOver<Apple> qapple = QueryOver.Of<Apple>()
.Where(x => (!x.IsRotten))
.And(Restrictions.IdEq(Projections.Property<Tree>(y => y.Id)))
// Or this one...
//.And(Restrictions.EqProperty(
// Projections.Property<Apple>(y => y.Tree.Id),
// Projections.Property<Tree>(y => y.Id)))
.Select(x => x.Id);
return this.NHibernateSession.QueryOver<Tree>()
.Where(x => x.Id.IsIn(ListOfTreeId))
.WithSubquery.WhereExists<Apple>(qapple)
.SelectList(list => list
.Select(z => z.Id).WithAlias(() => treeitem.Id)
.Select(z => z.Name).WithAlias(() => treeitem.Name)
.Select(z => z.Type).WithAlias(() => critem.Type)
.TransformUsing(Transformers.AliasToBean<Tree>())
.List<T>();
And the pseudo SQL I get is something like this:
SELECT id, name, type FROM trees WHERE id IN (1, 2, 3)
AND EXIST(SELECT id FROM apples WHERE NOT rotten AND apples.idtree = apples.id)
As you can see there's a problem with the subquery that use the same table Id instead of something like that:
EXIST(SELECT id FROM apples WHERE NOT rotten AND apples.idtree = tree.id)
I'm bit lost actually. Maybe there's another way to build this up.
Any help is welcome, thanks.

Im not sure why you are using resulttransformer when the return type is the same as the query type
return NHibernateSession.QueryOver<Tree>()
.Where(t => t.Id.IsIn(ListOfTreeId))
.JoinQueryOver<Apple>(t => t.Apples)
.Where(a => !a.IsRotten)
.List();
Update: the Compiler chooses ICollection<Apple> while it really should choose Apple therefor specify the generic argument in JoinQueryOver explicitly
Update2: to get them unique
opt 1)
...
.SetResultTransformer(Transformers.DistinctRootEntity());
.List();
opt 2)
Tree treeAlias = null;
var nonRottenApples = QueryOver.Of<Apple>()
.Where(a => !a.IsRotten)
.Where(a => a.Tree.Id == treeAlias.Id)
.Select(x => x.Id); <- optional
return NHibernateSession.QueryOver(() => treeAlias)
.Where(t => t.Id.IsIn(ListOfTreeId))
.WithSubquery.WhereExists(nonRottenApples)
.List();