Develop Reference

LINQ: Multiple Join With Max Revision Filter

So I have this line:
var transrevmax = db.TRANSACTs
.Where(x => x.SITE == "1" &&
x.DATE_IN >= dateinchoice &&
x.DATE_OUT <= dateoutchoice)
.GroupBy(x => x.TICKET_NO)
.Select(x => x.OrderByDescending(y => y.REV_NO).FirstOrDefault())
.ToList();
and it returns the exact list of transactions I want the join below to go through to obtain values from...
var exportrecovery = (from trans in transrevmax
join detail in db.DETAILs on new { TICKET_NO = trans.TICKET_NO, REV_NO = trans.REV_NO } equals new { TICKET_NO = detail.TICKET_NO, REV_NO = detail.REV_NO }
join job in db.JOBs on new { JOB_CODE = trans.JOB_CODE, CUST_CODE = trans.CUST_CODE } equals new { JOB_CODE = job.CODE, CUST_CODE = job.CUST_CODE }
join customer in db.CUSTOMERs on trans.CUST_CODE equals customer.CODE
join invoiced in db.INVOICEDs on trans.TICKET_NO equals invoiced.TICKET_NO
where trans.DATE_IN >= dateinchoice && trans.DATE_OUT <= dateoutchoice && trans.STATUS.ToString().Trim() != "V" && trans.STATUS.ToString().Trim() != "E"
select new { ADDRESS = customer.ADDRESS, CITY = customer.CITY, STATE = customer.STATE, ZIP = customer.ZIP, FREIGHT = detail.HAUL_CHGE + detail.FUEL_CHGE, JOB_NAME = job.NAME, HAUL_TAX = detail.HAUL_TAX, INVOICE_NO = invoiced.INVOICE_NO, CUST_NAME = customer.NAME, TAX_CODE = customer.TAX_CODE, MAT_CHGE = detail.MAT_CHGE, MAT_TAX = detail.MAT_TAX, MAT_CODE = detail.MAT_CODE, QTY = detail.QTY, PRICE = detail.PRICE, DATE_MOD = trans.DATE_OUT, REV_NO = trans.REV_NO, SITE = trans.SITE, TICKET_NO = trans.TICKET_NO, CUST_CODE = trans.CUST_CODE, JOB_CODE = trans.JOB_CODE }
).ToList();
... if I run the first line I get the transactions limited to only those with the max revision (what I want), and if I run the join (replacing the "transrevmax" with the table "db.TRANSACTs") I get the right range of ticket numbers, but it includes all revisions. I am stumped as to how I can use the joined tables and get only unique rows according to their (maximum) revision number. When these two are used in conjunction I receive zero rows. Please advise.

Remove the ToList on the transrevmax creation.

Split a string value in list using linq

I have a list with a column value like "0000000385242160714132019116002239344.ACK" i need to take last 6 digits from this value like "239344" without extension(.ack) when binding to the list.
And i need to find the sum of Salary field also.
My query looks like below.
var result = from p in Context.A
join e in B on p.Id equals e.Id
join j in Context.C on e.CId equals j.CId
where (e.Date >= periodFrom && e.Date <= periodTo)
group new
{
e,
j
} by new
{
j.J_Id,
e.Date,
e.Es_Id,
e.FileName,
j.Name,
e.ACK_FileName,
p.EmpSalaryId,
p.Salary
} into g
orderby g.Key.CId, g.Key.Es_Id, g.Key.Date, g.Key.FileName
select new
{
CorporateId = g.Key.CId,
ProcessedDate = g.Key.Date,
EstID = g.Key.Es_Id,
FileName = g.Key.FileName,
Name = g.Key.Name,
ack = g.Key.ACK_FileName,
EmpSalaryId = g.Key.EmpSalaryId,
Salary=g.Key.Salary
};
var Abc=result.ToList();

var result = (from p in Context.A
join e in B on p.Id equals e.Id
join j in Context.C on e.CId equals j.CId
where (e.Date >= periodFrom && e.Date <= periodTo)
group new { e, j } by new
{
j.J_Id,
e.Date,
e.Es_Id,
e.FileName,
j.Name,
ACK_FileName = e.ACK_FileName.Substring(e.ACK_FileName.IndexOf(".ACK") - 7, 11),
p.EmpSalaryId,
p.Salary
} into g
orderby g.Key.CId, g.Key.Es_Id, g.Key.Date, g.Key.FileName
select new
{
CorporateId = g.Key.CId,
ProcessedDate = g.Key.Date,
EstID = g.Key.Es_Id,
FileName = g.Key.FileName,
Name = g.Key.Name,
ack = g.Key.ACK_FileName,
EmpSalaryId = g.Key.EmpSalaryId,
Salary = g.Sum(item => item.Salary)
}).ToList();

LINQ condition inside where to filter

Im using ASP MVC, I have this LINQ to get employees DTR:
IEnumerable<DatatablesViewModel> viewmodel =
(from a in db.tHREmployees
join b in db.tTADTRs on a.EmpID equals b.EmpID
join c in db.tHRJobGrades on a.JobGrdID equals c.JobGrdID
join d in db.tTAShifts on b.ShftID equals d.ShftID
join e in db.tTADays on b.DayID equals e.DayID
where (b.LogDt >= PeriodDates.FromDt && b.LogDt <= PeriodDates.ToDt)
select new DatatablesViewModel
{
EmpID = a.EmpID,
Name = a.LastNm + ", " + a.FirstNm + ", " + a.MiddleNm,
JobGradeDesc = c.JobGrdDesc,
ShftNm = d.ShftNm,
DayType = e.DayNm,
LogDT = b.LogDt,
LogIn = b.LogIn,
LogOut = b.LogOut,
Absent = b.AbsDay,
Work = b.WorkHr,
Late = b.LateHr,
Overtime = b.OTHr,
Undertime = b.OTHr,
Nightdiff = b.NDHr,
NightPrem = b.NPHr,
ApprovedOT = b.AppOT,
ApprovedOB = b.AppOB,
ApprovedCoa = b.AppCOA,
ApprovedCs = b.AppCS,
Exception = b.ExcptStatus
}).OrderBy(x => x.EmpID);
In my view i have dropdown menu that has employee names with 'ALL' option.
I want to add a condition inside 'where' in above code somthing like:
if(parameter.selectedEmp != "ALL"){
Where(x => x.EmpID == param.CustomParam_EmpID) <-- add this filter
}
I want to select only what is needed in my query to avoid delay.

You don't need to add it in the Where clause directly. The IEnumerable and your LINQ query are only evaluated once you start to iterate through the collection. You could simply do something like this:
var relevantVMObjects =
(from a in db.tHREmployees
join b in db.tTADTRs on a.EmpID equals b.EmpID
join c in db.tHRJobGrades on a.JobGrdID equals c.JobGrdID
join d in db.tTAShifts on b.ShftID equals d.ShftID
join e in db.tTADays on b.DayID equals e.DayID
where (b.LogDt >= PeriodDates.FromDt && b.LogDt <= PeriodDates.ToDt)
select new DatatablesViewModel
{
EmpID = a.EmpID,
Name = a.LastNm + ", " + a.FirstNm + ", " + a.MiddleNm,
JobGradeDesc = c.JobGrdDesc,
ShftNm = d.ShftNm,
DayType = e.DayNm,
LogDT = b.LogDt,
LogIn = b.LogIn,
LogOut = b.LogOut,
Absent = b.AbsDay,
Work = b.WorkHr,
Late = b.LateHr,
Overtime = b.OTHr,
Undertime = b.OTHr,
Nightdiff = b.NDHr,
NightPrem = b.NPHr,
ApprovedOT = b.AppOT,
ApprovedOB = b.AppOB,
ApprovedCoa = b.AppCOA,
ApprovedCs = b.AppCS,
Exception = b.ExcptStatus
}).OrderBy(x => x.EmpID);
if(parameter.selectedEmp != "ALL")
relevantVMObjects = relevantVMObjects.Where(x => x.EmpID == param.CustomParam_EmpID);
IEnumerable<DatatablesViewModel> viewmodel = relevantVMObjects;

You can do this by OR condition
string selectedEmp=parameter.selectedEmp;
IEnumerable<DatatablesViewModel> viewmodel =
(from a in db.tHREmployees
join b in db.tTADTRs on a.EmpID equals b.EmpID
join c in db.tHRJobGrades on a.JobGrdID equals c.JobGrdID
join d in db.tTAShifts on b.ShftID equals d.ShftID
join e in db.tTADays on b.DayID equals e.DayID
where (b.LogDt >= PeriodDates.FromDt && b.LogDt <= PeriodDates.ToDt) &&
(selectedEmp != "ALL" || a.EmpID == param.CustomParam_EmpID)
select new DatatablesViewModel
{
...
}

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) }

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.