Can someone explain me why this does not work.
private void AdditionalLoad(List<PersonTypePerson> ptps)
{
using(var _context = new SPIS_Entities())
{
var m = (from ptp in ptps.Where(xx => xx.PersonID == _Person.ID)//_context.PersonTypePerson //
join pt in _context.PersonType on ptp.PersonTypeID equals pt.ID
join pta in _context.PersonTypeAttriubute.Where(p => p.active) on pt.ID equals pta.PersontypeID
select new { persontypeatribute = pta, availableatribute = pta.Attribute }).ToList();
var x = from ii in _context.InformationItem.Where(p=>p.PersonID ==_Person.ID)
join pta in _context.PersonTypeAttriubute.Where(p => p.active) on ii.PersonTypeAtributeID equals pta.ID
select new { persontype = pta.PersonType, attribute = pta.Attribute, information = ii };
var z = (from all in m
join fill in x on all.persontypeatribute.AttributeID equals fill.attribute.ID into ps
from fill in ps.DefaultIfEmpty()
select new
{
persontype = all.persontypeatribute.PersonType, //fill.persontype,
available = all.availableatribute,
attribute = fill.attribute,
information = fill.information
}).ToList();
}
}
The funniest thing is that I get a query result from "m" and "x". When it comes to the point to make the left join ("z") it breaks and throws a nullException, object reference not set to an instance of an object.
Related
This query takes 45ms on postgresql
select buf."Platform", buf."id", buf."idc"
from dbo."tableA" as buf
inner join dbo."TableB" as c
on c."idc" = buf."idc"::bigint
inner join dbo."TableC" as o
ON o."idc" = c."idc" and o."id" = buf."id"::bigint and o."idc" = buf."idc"::bigint
group by buf."Platform", buf."id", buf."idc"
however, when i write this with linq, it takes almos 1 sec. Why it takes so long ? how can i handle this
var List= (from buf in db.TableA
join c in db.TableB on buf.idc equals c.idc.ToString()
join o in db.TableC on new { x = c.idc, y = buf.idc, z = buf.id } equals new { x = o.idc, y = o.idc.ToString(), z = o.id.ToString() }
group new { buf } by new { buf.Platform, buf.id, buf.idc} into grp
select new
{
id= grp.Key.id,
idc= grp.Key.idc,
platform = grp.Key.Platform,
count = grp.Count(),
}
).ToList();
I'm trying to join two group by queries to get one results set.
var query = from PP in _db.paymentPlans
join APP in _db.Applications on PP.applicationID equals APP.ApplicationId
join C in _db.Courses on APP.courseID equals C.courseID
where PP.active == true && APP.agentID == agentID
orderby C.courseID ascending
group new {C,PP} by new {C.courseID} into totalRecievable
// Query 1
from PD in _db.paymentDetails
join PP in _db.paymentPlans on PD.paymentPlanID equals PP.paymentPlanID
join APP in _db.Applications on PP.applicationID equals APP.ApplicationId
join C in _db.Courses on APP.courseID equals C.courseID
where PP.active == true && APP.agentID == agentID
orderby C.courseID ascending
group new { C,PD } by new { C.courseID, C.cricosCode, C.courseName } into paymentsCourseWise
// Query 2
select new PdPpAppCourseModel
{
courseID = paymentsCourseWise.Key.courseID,
cricosCode = paymentsCourseWise.Key.cricosCode,
courseName = paymentsCourseWise.Key.courseName,
totalAmount = totalRecievable.Sum(x => x.PP.totalAmount),
paidAmount = paymentsCourseWise.Sum(x => x.PD.paidAmount)
}).ToList();
Total about is taken from query 1 as it should group in payment plan(PP) level.
You can only combine enumerations of the same type, you could project both to a common class and then concatenate them:
var result1 = db1.table.Where(a=>a.value>0).Select( x=> new Foo() { //set props });
var result2 = db2.table.Where(a=>a.value>0).Select( x=> new Foo() { //set props });
var resultSum = result1.Concat(result2);
Similarly you can apply this in your code and join this two groups.
I need to convert an SQL query to Linq/Lambda expression, I am trying doing the same but not getting the desired results.
SQL:
SELECT b.*, n.notes
FROM Goal_Allocation_Branch as b
INNER JOIN Goal_Allocation_Product as g
on b.Product = g.ProductID
and b.Year = g.Year
left join Goal_Allocation_Branch_Notes as n
on b.branchnumber = n.branch
and n.year = ddlYear
WHERE b.Year = ddlYear
and g.Show = 1
and branchnumber = ddlBranch
I am new to Linq , I am getting error on Join Clause , and X is not containing any data from first Join
var result = (from br in _DB_Branches.Goal_Allocation_Branches
join pr in _DB_Product.Goal_Allocation_Products on new { br.Product, br.Year } equals new {Product= pr.ProductID, Year= pr.Year }
join n in _DB_Notes.Goal_Allocation_Branch_Notes.Where(n => n.Year == ddlYear) on br.BranchNumber equals n.Branch into Notes
from x in Notes.DefaultIfEmpty()
select new BranchNotesViewModel
{
Year = x.Year,
BranchNumber = x.Branch,
ProductID = x.ProdID
}
).ToList();
Update: My First Join clause initially giving error "The type of one of the expression in Join Clause is incorrect " is resolved, when I Changed On Clause
from
"on new { br.Product, br.Year } equals new {pr.ProductID, pr.Year}"
"on new { br.Product, br.Year } equals new {Product=pr.ProductID,Year= pr.Year}"
still not getting desired results as expected from above SQL query. Please advise..
It should be something like this (see note):
var result =
(from br in _DB_Branches.Goal_Allocation_Branches
join pr in _DB_Product.Goal_Allocation_Products
on br.Product equals pr.ProductID
from n in _DB_Notes.Goal_Allocation_Branch_Notes.Where(x=>
x.branch == br.branchnumber
&& x.year == ddlYear
).DefaultIfEmpty()
where
br.Year == ddlYear
&& and br.Year == pr.Year
&& pr.Show == 1
&& br.branchnumber == ddlBranch
select new BranchNotesViewModel
{
Year = ...,
BranchNumber = ...,
ProductID = ...
}
).ToList();
Note: Change the select, to the properties you want.
Edit: fixed some syntax errors.
I finally figured out the correct answer. Working absolutely fine
var result = (from br in _DB_Branches.Goal_Allocation_Branches
join pr in _DB_Product.Goal_Allocation_Products on new { br.Product, br.Year } equals new { Product = pr.ProductID, Year = pr.Year }
join n in _DB_Notes.Goal_Allocation_Branch_Notes.Where(n=>n.Year==ddlYear) on br.BranchNumber equals n.Branch into Notes
where br.Year==ddlYear
&& pr.Show== true
&& br.BranchNumber==ddlBranch
from x in Notes.DefaultIfEmpty()
select new BranchNotesViewModel
{
Year=x.Year,
BranchNumber=x.Branch,
ProductID=br.Product,
Notes = x.Notes,
//All other fields needed
}
).ToList();
I am new to Entity, and have a question regarding a LINQ statement.
Below appears my code, it appears with exception to "TotalFoults" field. He always gives 0.
Could anyone help me because all the results in the "TotalFoults" column have a value above zero.
Thank you very much.
var result = (from sr in db.StudentsResult
join F in db.Fouls on sr.Enrollment equals F.Enrollment into F_join
from F in F_join.DefaultIfEmpty()
join S in db.Students on sr.Enrollment equals S.Enrollment into A_join
from A in A_join.DefaultIfEmpty()
where
F.Day != null
group new { sr, s } by new
{
sr.Enrollment ,
sr.Name,
sr.Number,
sr.Classes,
s.Discount
} into g
orderby
g.Key.Classes,
g.Key.Number,
g.Key.Name
select new frequencyMod()
{
Enrollment = g.Key.Enrollment ,
StudentName = g.Key.Name,
StudentFile= g.Key.Number,
Classes = g.Key.Classes,
TotalFoults = (from m0 in db.Foults
where
m0.Enrollment == g.Key.Enrollment
group m0 by new
{
m0.Enrollment
} into a
select new
{
Total = a.Sum(p => p.Foults)
}).FirstOrDefault().Total
}).ToList();
I'm unable to convert this SQL query into a working linq statement
select sum(cena), id_auta, max(servis)
from dt_poruchy left outer join mt_auta on dt_poruchy.id_auta=mt_auta.id
where dt_poruchy.servis>=3 group by id_auta;
I tryed something like this but i cant handle the select statement
var auta = from a in MtAuta.FindAll()
join p in DtPoruchy.FindAll() on a equals p.MtAuta into ap
from ap2 in ap.DefaultIfEmpty()
where ap2.SERVIS >= 3
group ap2 by ap2.ID into grouped
select new {
I'll appreciate any help!
Based on the limited information provided (which tables are certain fields from?), here is what I came up with.
var auta = from a in MtAuta.FindAll()
let p = a.DtPoruchys.Where(s => s.SERVIS >= 3)
select new
{
Id = a.Id,
CenaSum = p.Sum(c => c.Cena),
Servis = p.Max(s => s.SERVIS)
};
I've reached this solution (supposing "cena" belongs to MtAuta.FindAll()):
var auta = from e in
(from a in DtPoruchy.FindAll()
where a.SERVIS >= 3
join p in MtAuta.FindAll() on a.MtAuta equals p.Id into ap
from ap2 in ap.DefaultIfEmpty()
select new
{
Cena = ap.cena,
IdAuta = a.MtAuta,
Servis = a.servis
})
group e by e.IdAuta into g
select new
{
Cena = g.Sum(e => e.cena),
IdAuta = g.Key,
Servis = g.Max(e => e.servis)
};
I am not sure which table cena and servis are coming from but to create grouped sum you do something like.
select new { Sum = grouped.Sum( x => x.cena ) }
and to get max
select new { Max = grouped.Group.Max( x => x.servis ) }
Here is a good reference for you.
MSDN - 101 LINQ Samples
I've modified your solution little bit and i got it working like this:
var auta = from jo in
(
from a in MtAuta.FindAll()
join p in DtPoruchy.FindAll() on a equals p.MtAuta into ap
from ap2 in ap.DefaultIfEmpty()
where ap2.SERVIS >= 3
select new
{
Cena = ap2.CENA,
Idauto = ap2.ID_AUTA,
Servis = ap2.SERVIS
}
)
group jo by jo.Idauto into g
select new
{
Cena = g.Sum(jo => jo.Cena),
IdAuto = g.Key,
Servis = g.Max(jo => jo.Servis)
};
I just curious if this is the best solution?