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How to write two left joins in the linq

var CCEScholasticTests = db.CCEScholasticTests.Where(x => x.CCEvaluationID == CCEValuationID && x.SubjectID == SubjectID && x.ClassID == ClassID && (x.BranchSectionID == BranchSectionID || BranchSectionID == 0) && x.languageTypeSubjectID == languageTypeSubjectID && (x.BranchID == BranchID || x.BranchID == 0) && x.IsOnlyGrade == false).Select(x => x).ToList();
var res = (from a in CCEScholasticTests
join b in db2.CCESubjectSkills on new { key1 = a.CCESubjectSkillID } equals new { key1 = b.CCESubjectSkillID } into join1
from joinRes in join1.DefaultIfEmpty(new CCESubjectSkill())
join c in db2.CCEScholasticSkillsMasters on new { key = joinRes.CCEScholasticSkillMasterID } equals new { key = c.CCEScholasticSkillMasterID } into join2
from joinRes2 in join2.DefaultIfEmpty(new CCEScholasticSkillsMaster())
select new EvaluationBluk
{
BranchSectionID = a.BranchSectionID,
CCEScholasticTestID = a.CCEScholasticTestID,
CCEScholasticTestName = a.CCEScholasticTestName,
//CCESubjectSkillName = joinRes.CCESubjectSkillName,
CCESubjectSkillID = a.CCESubjectSkillID,
CCEvaluationID = a.CCEvaluationID,
MaxMarks = a.MaxMarks,
SubjectID = a.SubjectID,
TestDate = a.TestDate,
MarksEntryLastDate = a.MarksEntryLastDate,
//CCEScholasticSkillMasterID = joinRes.CCEScholasticSkillMasterID,
//CCEScholasticSkillName = joinRes2.CCEScholasticSkillName
}).ToList();
how to write multiple left joins in linq.. the below linq query i am writing based on this sp
CREATE procedure [dbo].[GetClassCCEScholasticTestsOnlyMarksTest]
(
#BranchSectionID int,
#CCEvaluationID int,
#SubjectID int,
#ClassID int ,
#languageTypeSubjectID int ,
#BranchID int
)
as
select c1.BranchSectionID,c1.CCEScholasticTestID,c1.CCEScholasticTestName,s1.CCESubjectSkillName,
c1.CCESubjectSkillID,c1.CCEvaluationID,c1.MaxMarks,c1.SubjectID,convert(varchar,c1.TestDate,101) as TestDate,convert(date,c1.MarksEntryLastDate,101)as MarksEntryLastDate
,isnull(s1.CCEScholasticSkillMasterID,-1) as CCEScholasticSkillMasterID ,cm.CCEScholasticSkillName
from dbo.CCEScholasticTests c1
left join CCESubjectSkills s1 on s1.CCESubjectSkillID=c1.CCESubjectSkillID
left join CCEScholasticSkillsMaster cm on cm.CCEScholasticSkillMasterID=s1.CCEScholasticSkillMasterID
where c1.CCEvaluationID=#CCEvaluationID and c1.SubjectID=#SubjectID
and c1.ClassID=#ClassID and (c1.BranchSectionID=#BranchSectionID or c1.BranchSectionID=0) and c1.languageTypeSubjectID =#languageTypeSubjectID
and (c1.BranchID=#BranchID or c1.BranchID=0)and c1.IsOnlyGrade=0
order by c1.CCEScholasticTestID asc
in sql it throws 3 rows but in linq it throws 1 row only... what wrong in my code

var result=CCEScholasticTests.join(db2.CCESubjectSkills ,o=>o.CCESubjectSkillID, od=>od.CCESubjectSkillID,(o, od)=> new
{
BranchSectionID = o.BranchSectionID,
CCEScholasticTestID = o.CCEScholasticTestID,
CCEScholasticTestName = o.CCEScholasticTestName,
CCESubjectSkillID = o.CCESubjectSkillID,
CCEvaluationID = o.CCEvaluationID,
MaxMarks = o.MaxMarks,
SubjectID = o.SubjectID,
TestDate = o.TestDate,
MarksEntryLastDate = o.MarksEntryLastDate,
CCEScholasticSkillMasterID = od.CCEScholasticSkillMasterID
}).join(db2.CCEScholasticSkillsMasters, s=>s.CCEScholasticSkillMasterID = t.CCEScholasticSkillMasterID, t=>t.CCEScholasticSkillMasterID,(s,t)=> new
{
BranchSectionID = o.BranchSectionID,
CCEScholasticTestID = o.CCEScholasticTestID,
CCEScholasticTestName = o.CCEScholasticTestName,
CCESubjectSkillID = o.CCESubjectSkillID,
CCEvaluationID = o.CCEvaluationID,
MaxMarks = o.MaxMarks,
SubjectID = o.SubjectID,
TestDate = o.TestDate,
MarksEntryLastDate = o.MarksEntryLastDate,
CCESubjectSkillName = t.CCESubjectSkillName,
CCEScholasticSkillMasterID = t.CCEScholasticSkillMasterID,
CCEScholasticSkillName = t.CCEScholasticSkillName
}).tolist();
I dont know the exact relation between the table but, i have assumed and written query. hope it helps u

How to get the group sum in my complex linq query

below I have listed a linq query that works properly in my asp.net.mvc web app.
In addition I would like to group over 'allowance.ParameterId' in order to get the group sum for 'allowance.Freight (instead of multiple records for the given key).
var query = from ara in aras
join company in companies on ara.Id equals company.ARAId
join wasteWater in wasteWaters on company.Id equals wasteWater.CompanyId
join allowance in allowances on wasteWater.Id equals allowance.WasteWaterID
join parameter in parameters on allowance.ParameterId equals parameter.Id into JoinedParameterAllowance
from parameter in JoinedParameterAllowance.DefaultIfEmpty()
where company.Activ == true && company.End == null && company.Template == false
&& wasteWater.End == null
select new FreightSummaryViewModel
{
AraName = ara.Name,
AraId = ara.Id,
AllowedParameter = parameter.Name,
AllowedFreight = allowance.Freight
};
I have tried to insert 'group ...' but failed to get it right.
Could someone help me please to set up the proper syntax?
Thank you in advance, Manu

I have little idea about relations in your database, so I improvised...
// Some dummy data to play with
var aras = Enumerable.Range(0, 5).Select(i => new { Id = i, Name = "Ara" + i });
var companies = Enumerable.Range(0, 15).Select(i => new { Id = i, ARAId = i % 5, Activ = true, End = (DateTime?)null, Template = false });
var wasteWaters = Enumerable.Range(0, 35).Select(i => new { Id = i, CompanyId = i / 15, End = (DateTime?)null });
var allowances = Enumerable.Range(0, 70).Select(i => new { Id = i, WasteWaterID = i, ParameterId = i % 4, Freight = i * 1000 });
var parameters = Enumerable.Range(0, 4).Select(i => new { Id = i, Name = "Parameter" + i });
And this is what I believe you looked for:
var query =
from ara in aras
join company in companies on ara.Id equals company.ARAId
join wasteWater in wasteWaters on company.Id equals wasteWater.CompanyId
join allowance in allowances on wasteWater.Id equals allowance.WasteWaterID
join parameter in parameters on allowance.ParameterId equals parameter.Id
into JoinedParameterAllowance
// from parameter in JoinedParameterAllowance.DefaultIfEmpty()
where true
&& company.Activ == true
&& company.End == null
&& company.Template == false
&& wasteWater.End == null
group allowance by new
{
AraName = ara.Name,
AraId = ara.Id,
ParameterId = allowance.ParameterId
} into myGroup
select new //FreightSummaryViewModel
{
AraName = myGroup.Key.AraName,
AraId = myGroup.Key.AraId,
AllowedParameter = myGroup.Key.ParameterId,
AllowedFreight = myGroup.Sum(g => g.Freight)
};

Transforming T-SQL Query into C# LINQ with joins on multiple conditions and also grouping on multiple conditions

First I want to say hello, I'm new to this site ;-)
My problem is to transform the following sql-query into a c# linq-query.
( I HAVE searched hard for an existing answer but I'm not able to combine the solution for
the joins on multiple conditions and the grouping / counting ! )
The sql-query :
DECLARE #datestart AS DATETIME
DECLARE #dateend AS DATETIME
SET #datestart = '01.04.2014'
SET #dateend = '30.04.2014'
SELECT md1.value AS [controller],md2.value AS [action], COUNT(md2.value) AS [accesscount], MAX(re.TIMESTAMP) AS [lastaccess] FROM recorderentries AS re
INNER JOIN messagedataentries AS md1 ON re.ID = md1.recorderentry_id AND md1.position = 0
INNER JOIN messagedataentries AS md2 ON re.ID = md2.recorderentry_id AND md2.position = 1
WHERE re.TIMESTAMP >= #datestart AND re.TIMESTAMP <= #dateend
AND re.messageid IN ('ID-01','ID-02' )
GROUP BY md1.value,md2.value
ORDER BY [accesscount] DESC
Any suggestions are welcome ...
What i have so far is this :
var _RecorderActionCalls = (from r in _DBContext.RecorderEntries
join m1 in _DBContext.MessageDataEntries on
new {
a = r.ID,
b = 0
} equals new {
a = m1.ID,
b = m1.Position
}
join m2 in _DBContext.MessageDataEntries on
new {
a = r.ID,
b = 0
} equals new {
a = m2.ID,
b = m2.Position
}
where r.TimeStamp >= StartDate & r.TimeStamp <= EndDate & (r.MessageID == "VAREC_100_01" | r.MessageID == "VAAUTH-100.01")
group r by new { md1 = m1.Value, md2 = m2.Value } into r1
select new { controller = r1.Key.md1, action = r1.Key.md2, count = r1.Key.md2.Count() }).ToList();
But this throws an exception ( translated from german ) :
DbExpressionBinding requires an input expression with a Listing Result Type ...
UPDATE : Back with headache ... ;-)
I found a solution to my problem :
var _RecorderActionCalls = _DBContext.RecorderEntries
.Where(r => r.TimeStamp >= StartDate & r.TimeStamp <= EndDate & (r.MessageID == "VAREC_100_01" | r.MessageID == "VAAUTH-100.01"))
.GroupBy(g => new { key1 = g.MessageData.FirstOrDefault(md1 => md1.Position == 0).Value, key2 = g.MessageData.FirstOrDefault(md2 => md2.Position == 1).Value })
.Select(s => new {
ControllerAction = s.Key.key1 + " - " + s.Key.key2,
Value = s.Count(),
Last = s.Max(d => d.TimeStamp)
}).ToList();
With this syntax it works for me. Thank you for thinking for me :-)

Something like that:
List<string> messageIdList = new List<string> { "ID-01", "ID-02" };
from re in RecorderEntries
from md1 in MessageDataEntries
from md2 in MessageDataEntries
where re.ID = md1.recorderEntry_id && md1.position == 0
where re.ID = md2.recorderEntry_id && md2.position == 1
where idList.Contains(re.messageid)
let joined = new { re, md1, md2 }
group joined by new { controller = joined.md1.value, action = joined.md2.value } into grouped
select new {
controller = grouped.Key.controller,
action = grouped.Key.action,
accesscount = grouped.Where(x => x.md2.value != null).Count(),
lastaccess = grouped.Max(x => x.re.TimeStamp) }

How to write Outer Join using LINQ

I am using the below Inner Join to retrive the Data between the two tables, but all data is not getting populated. I tried implementing Outer join by connecting using CCY1== CCY1 and PCODE == PCODE, but no luck.
var q = from g1 in TableCCY1.AsEnumerable()
join g2 in TableCCY2.AsEnumerable()
on g1.Field<string>("CCY1") equals g2.Field<string>("CCY1")
where g1.Field<string>("PCODE") == g2.Field<string>("PCODE")
select new
{
g1currency = g1.Field<string>("CCY1"),
g2currency = g2.Field<string>("CCY1"),
g1code = g1.Field<string>("PCODE"),
g2code = g2.Field<string>("PCODE"),
g1Amt1 = g1.Field<string>("AMT1"),
g2Amt2 = g2.Field<string>("AMT2")
};
Thanks for your help.

For left join you can use this approuch: http://msdn.microsoft.com/en-us/library/vstudio/bb397895.aspx
The code should be:
var q = from g1 in TableCCY1
join g2 in TableCCY2 on g1.CCY1 equals g2.CCY1 && g1.PCODE equals g2.PCODE into TableCCY3
from g3 in TableCCY3.DefaultIfEmpty()
select new
{
g1currency = g1.CCY1,
g2currency = (g3 == null ? String.Empty : g3.CCY1),
g1code = g1.PCODE,
g2code = (g3 == null ? String.Empty : g3.PCODE),
g1Amt1 = g1.AMT1,
g2Amt2 = (g3 == null ? 0 : g3.AMT2)
};

It looks like you just want to union/concat the two tables into one and then just group on those two columns. You're not logically joining the two tables. That actually makes it much easier.
var q = from row in TableCCY1.AsEnumerable().Concat(TableCCY2.AsEnumerable())
group row by new
{
CCY1 = row.Field<string>("CCY1"),
PCode = row.Field<string>("PCODE")
} into matches
select new
{
CCY1 = matches.Key.CCY1,
PCODE = matches.Key.PCode,
Sum = matches.Sum(match => match.Field<decimal?>("AMT2")),
};

Entity Framework - Results from subquery, speed issue?

I've made a query to get a list of articles, each bound to a "header",
so i retrieve the header plus the related articles and their properties.
The query works, however in its current style it is
Somewhat messy ( in my opinion)
The .ToList() takes way longer than i would expect.
Does anyone see any obvious reason for the speed-issue?
var offerheaders =
from o in dbcontext.F_CAB_OFFER_HEADERS
where
o.OFHD_FK_BUYER == userinfo.orgaTypeSequence
&& o.OFHD_VALID_FROM <= userinfo.selectedDate
&& o.OFHD_VALID_TO >= userinfo.selectedDate
&& o.OFHD_DELETED_YN == 0
&& o.OFHD_DELETED_BY_OWNER_YN == false
&& o.OFHD_OFFER_TYPE == userinfo.offerType
orderby o.OFHD_NO ascending
select o;
var offerlist =
from ofhd in offerheaders
select new {
ofhd = new {
OfferNo = ofhd.OFHD_NO,
OfferSequence = ofhd.OFHD_SEQUENCE,
ValidFrom = ofhd.OFHD_VALID_FROM,
ValidTo = ofhd.OFHD_VALID_TO,
OfferType = ofhd.OFHD_OFFER_TYPE,
Maingroup = new { cdmg_seq = ofhd.F_CAB_CD_MAIN_GROUP_TYPE.CDMG_SEQUENCE, Desc = ofhd.F_CAB_CD_MAIN_GROUP_TYPE.CDMG_DESC },
Supplier = new {
Name = ofhd.F_CAB_GROWER.F_CAB_ORGANISATION.ORGA_NAME,
Pic = ofhd.F_CAB_GROWER.F_CAB_ORGANISATION.ORGA_FK_PICTURE,
Seq = ofhd.F_CAB_GROWER.GROW_SEQUENCE
},
Caption = ofhd.OFHD_CAPTION,
Seperate = ofhd.OFHD_SHOW_SEPARATE_YN,
//ofdts = (from ofdt in dbcontext.F_CAB_OFFER_DETAILS.Where(x => x.OFDT_FK_OFFER_HEADER == ofhd.OFHD_SEQUENCE && x.OFDT_NUM_OF_ITEMS > 0 && x.OFDT_LATEST_DELIVERY_DATE_TIME > compareDateTime && x.OFDT_LATEST_ORDER_DATE_TIME > compareDateTime)
ofdts = from ofdt in dbcontext.F_CAB_OFFER_DETAILS
join props in dbcontext.F_CAB_CAB_PROP on ofdt.OFDT_FK_CAB_CODE equals props.PROP_FK_CABC_SEQ
join cabcode in dbcontext.F_CAB_CD_CAB_CODE on ofdt.OFDT_FK_CAB_CODE equals cabcode.CABC_SEQUENCE
join cabgroup in dbcontext.F_CAB_CD_CAB_GROUP on cabcode.CABC_FK_CAB_GROUP equals cabgroup.CDGR_SEQUENCE
join grouptype in dbcontext.F_CAB_CD_GROUP_TYPE on cabgroup.CDGR_FK_GROUP_TYPE equals grouptype.CDGT_SEQUENCE
join maingrouptype in dbcontext.F_CAB_CD_MAIN_GROUP_TYPE on grouptype.CDGT_FK_MAIN_GROUP equals maingrouptype.CDMG_SEQUENCE
join caca in dbcontext.F_CAB_CAB_CASK_MATRIX on ofdt.OFDT_FK_CACA_SEQ equals caca.CACA_SEQUENCE
join cask in dbcontext.F_CAB_CD_CASK on caca.CACA_FK_CASK equals cask.CDCA_SEQUENCE
join vbncode in dbcontext.F_CAB_CAB_VBN_MATRIX on cabcode.CABC_SEQUENCE equals vbncode.CVMA_FK_CAB_CODE
join grel in dbcontext.F_CAB_GENERAL_RELATIONS on ofdt.OFDT_FK_GREL_SEQ equals grel.GREL_SEQUENCE into greltable
from g_loj in greltable.DefaultIfEmpty()
where
ofdt.OFDT_FK_OFFER_HEADER == ofhd.OFHD_SEQUENCE
&& ofdt.OFDT_NUM_OF_ITEMS > 0
&& props.PROP_FK_CDLA_SEQ == userinfo.lang.CDLA_SEQUENCE
orderby props.PROP_CAB_DESC ascending
select new {
Desc = props.PROP_CAB_DESC,
Group = new { cdgr_seq = cabgroup.CDGR_SEQUENCE, Desc = cabgroup.CDGR_DESC },
Grouptype = new { grouptype.CDGT_SEQUENCE, Desc = grouptype.CDGT_DESC },
Properties = new CABProperties { props = props },
Price = ofdt.OFDT_ITEM_PRICE,
PIC_SEQ = ofdt.OFDT_FK_PICTURE ?? ((cabcode.CABC_FK_PICTURE ?? cabcode.CABC_SEQUENCE)),
PIC_URL = ofdt.OFDT_EXT_PICTURE_REF ?? "",
Seq = ofdt.OFDT_SEQUENCE,
Available = ofdt.OFDT_NUM_OF_ITEMS,
CabCode = ofdt.F_CAB_CD_CAB_CODE.CABC_CAB_CODE,
VBNCode = vbncode.CVMA_FK_VBN_CODE,
Remark = ofdt.OFDT_REMARK,
IsSpecial = ofdt.OFDT_SPECIAL_YN,
Arrived = inTransit ? ofdt.OFDT_ARRIVAL_DATE < DateTime.Now : true,
Cask = new CABCask { cask = cask, caca = caca },
Supplier = g_loj == null ? (ofdt.OFDT_SUPPLIER ?? "") : g_loj.GREL_NAME,
SupplierWeb = g_loj == null ? "" : g_loj.GREL_WEBSITE_URL,
SupplierLogo = g_loj == null ? ofhd.F_CAB_GROWER.F_CAB_ORGANISATION.ORGA_FK_PICTURE : g_loj.GREL_FK_PICT_SEQ,
SupplierSeq = g_loj == null ? -1 : g_loj.GREL_SEQUENCE,
}
}
};
userinfo.mainofferlist = offerlist.ToList();

As Daniel Kelly also mentioned the ToList function is where your query is executed, because these LinqToEntities queries are executed at the point where they are first enumerated, and ToList does that to be able to create a list.
Basically the reason why your querying takes so much time can be separated into two different reasons:
you are using too much projections and I thine (the parts with new {
})
your query has an incredible amount of join clauses
I would recommend to separate your query into subqueries, and run them separately like the first part in
...
select o
use
...
select o).ToList()
by breaking down the main query where you have a lot of subqueries it will be faster and much more readable, so you have less "messiness".
And last but not least you should create mapping for the anonymous objects, and use those classes other than projection that should speed up your query.