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SQL query to LINQ or Lambda

I have the following query
SELECT sdb.student_due_by_month_id, sdb.due_month_year, sum(sdb.due_total_month) FROM user_student ust
INNER JOIN student std ON ust.student_id = std.student_id
INNER JOIN student_due_by_month sdb ON std.student_id = sdb.student_id
WHERE ust.user_id = 2
GROUP BY sdb.student_due_by_month_id, sdb.student_due_by_month_id, sdb.due_month_year
I need to convert it to linq or a lambda expression.
I'm trying to turn him into a linq and this is what I have so far:
var user_due_month = await (from ust in _context.Users_students
join std in _context.Students on ust.student_id equals std.student_id
join sdb in _context.Students_dues_by_months on std.student_id equals sdb.student_id
where ust.user_id == user_id
group sdb by new { sdb.student_due_by_month_id, sdb.due_month_year } into g //from here i have yet to complete the linq query, help?
I don't know what would be missing to complete my linq query correctly, and also be able to pass it to a viewmodel.
Thanks a lot!!

LINQ Select newest records that have distinct ForeignKeyId column

I have the following SQL query:
SELECT
table1.Id AS EinAusgangId,
table1.Ausgabedatum,
table1.Rueckgabedatum,
table1.WerkzeugId,
cpmWerkzeug.Name
FROM cpmEinAusgang AS table1
INNER JOIN cpmWerkzeug ON table1.WerkzeugId = cpmWerkzeug.Id
WHERE table1.Id = (SELECT MAX(Id) AS Expr1
FROM dbo.cpmEinAusgang
WHERE table1.WerkzeugId = WerkzeugId)
My aim is to convert the whole query into a LINQ statement for further use in a .Net Application. I already converted joined tables to LINQ but is it also possible to use a select in the where clause?
This is what I got so far, which gives me almost the same result as the SQL statement above, but has major errors when the table cpmEinAusgang contains more then one record for one cpmWerkzeug
using (var dbContext = new cpmEntities())
{
var werkzeuge = from w in dbContext.cpmWerkzeug
join e in dbContext.cpmEinAusgang
on w.Id equals e.WerkzeugId
where e.Rueckgabedatum == null
orderby w.Name
select w;
return werkzeuge.ToList();
}
Has anyone an idea how to achieve the above sql in linq?
Thanks for your help. :)
EDIT:solved (see below)

var werkzeugeImUmlauf = from w in dbContext.cpmWerkzeug
join e in dbContext.cpmEinAusgang
on w.Id equals e.WerkzeugId
where e.Id == dbContext.cpmEinAusgang.Where(x => x.WerkzeugId == e.WerkzeugId).Max(x => x.Id) select w;
This is the final solution. As mentioned by Mittal in his answer, it is possible to write a sub-query in LINQ.

Yes, you can write Sub Query in LINQ as well.
var werkzeuge = from w in dbContext.cpmWerkzeug
join e in dbContext.cpmEinAusgang
on w.Id equals e.WerkzeugId
where w.id = (dbContext.cpmEinAusgang.Max(x => x.id)) AND w.WerkzeugId = WerkzeugId

convert SQL query to Linq

Could somebody assist me in converting a sql query into LINQ ? I well understand SQL queries, but I am a novice in Linq. Thank you so much for help me.
SELECT
subConsulta."NitIps",
subConsulta."NumFactura",
COUNT(*)
FROM
(SELECT
DISTINCT acf."NitIps",
acf."NumFactura",
acf."TipoSoporte"
FROM
"t_ArchivoCentralFacturacion" AS acf
inner join "t_TRCompartaTiposDocumentalesAC" AS ctd
on
acf."TipoSoporte"= ctd."Id"
GROUP BY
acf."NitIps",
acf."NumFactura",
acf."TipoSoporte")as subConsulta
GROUP BY
subConsulta."NitIps",
subConsulta."NumFactura"
ORDER BY
subConsulta."NitIps",
subConsulta."NumFactura"

If you map your tables to entities it looks like follow:
var first = from archivoCentralFacturacion in ArchivoCentralFacturacions
group archivoCentralFacturacion by new {
c.NitIps,
c.NumFactura,
c.TipoSoporte
} into subConsulta
select subConsulta;
var result = (from f in first
group f by new {
f.NitIps,
f.NumFactura
} into r
select new {
NitIps = r.NitIps,
NumFactura = r.NumFactura,
ResultCount = r.Count()
}).OrderBy(x => x.NitIps).ThenBy(x => x.NumFactura);

getting error in joining dictionary with table

I want to have join query from a table with a dictionary based on a common field, my query is:
var query = from c in db.Exp
join d in lstUniprotDic on c.UniID equals d.Key
select new
{
c.UniID,
IdentityPercent=d.Value.ToString(),
c.PrId,
c.SpotNo
}
but i got the following error
Local sequence cannot be used in LINQ to SQL implementation of query operators except the Contains() operator.

That pretty much says it all. You can't use the dictionary in your LINQ to SQL query except when using Contains.
Solution:
(from c in db.Exp where lstUniprotDic.Keys.Contains(c.UniID) select c).AsEnumerable()
join d in lstUniprotDic on c.UniID equals d.Key
select new
{
c.UniID,
IdentityPercent=d.Value.ToString(),
c.PrId,
c.SpotNo
}
I am not sure if the usage of lstUniprotDic.Keys in the LINQ to SQL query is actually working.
If not, try using this code instead:
var ids = lstUniprotDic.Keys.ToArray();
(from c in db.Exp where ids.Contains(c.UniID) select c).AsEnumerable()
join d in lstUniprotDic on c.UniID equals d.Key
select new
{
c.UniID,
IdentityPercent=d.Value.ToString(),
c.PrId,
c.SpotNo
}

How to convert SQL to linq for this query

I want to convert this query into linq, please help:
select
mr_ssample.objectid,
mr_ssample.stcode
from mr_ssample
inner join mr_wsample on mr_ssample.objectid = mr_wsample.objectid
And mr_ssample.stcode in( select stcode
from mr_wsample)
i tried this in C#
var query = from ssamp in marineEntity.MR_SSAMPLE
join wsamp in marineEntity.MR_WSAMPLE on ssamp.OBJECTID equals wsamp.OBJECTID && ssamp.stcode.contains(wsamp.stcode)
select new
{};
However, I could not access wsamp in contains, or I dont know the alternative of this.

give this a try,
var _result = from a in mr_ssample
join b in mr_wsample on a.objectid equals b.objectid
where (from c in mr_wsample select new {c.stcode})
.Contains(new {a.stcode})
select new {a.objectid, a.stcode}