I am having a bug in editing the following LINQ Query
var tNumber = 10001;
var data = from r in R_TABL
join pt in PT_TABL
on r.R_id equals pt.id into trans
join tu in TU_TABL
on tNumber equals tu.tUNUMBER
from tr in trans.DefaultIfEmpty()
where r.r_number == tNumber &&
r.sequence == "101001"
select new MyDto
{
IsExisting = tu.tUNUMBER != null ? true : false
};
I added the following line:
join tu in TU_TABL on tNumber equals tu.tUNUMBER
and
IsAppAssist = tu.tUNUMBER != null ? true : false
I need to join the TU_TABL to check if number exist in the table. In the c# method I pass in the parameter, tNumber and check on the
"join tu in TU_TABL on tNumber equals tu.tUNUMBER" to see if there is a match. I create a new DTo and set the boolean IsExisting to if tu.tuNumber != null.
If the number exists, IsExisting is true, else false.
When I checked the result, all the records coming back are false. What is the correct way to correct the linq join to check if a number exist in the join table?
The left side of your equals clause does not check against a column; you should be comparing it to r's t_number:
join tu in TU_TABL
on r.r_number equals tu.tUNUMBER
Related
I have the following query in one of my Entity Framework Core API controllers:
var plotData = await (from nl in _context.BookList
join ql in _context.PlotList on nl.PlotId equals ql.PlotId
join qc in _context.PlotChoices on ql.PlotId equals qc.PlotId
join nk in _context.BookLinks.DefaultIfEmpty() on qc.ChoiceId equals nk.ChoiceId
where nl.Id == ID
select new
{ .. }
I need it to return all rows even if data doesn't exist in the BookLinks table.
However, it's not returning rows if there is no data data in the BookLinks table for that row.
But this SQL query, from which I'm trying to model from, does return data...it returns nulls if there is no data in BookLinks.
select * from BookList bl
left join PlotList pl ON bl.plotId = bl.plotId
left join PlotChoices pc ON pl.plotId = pc.plotId
left join BookLinks bk ON pc.choiceID = bk.choiceID
where nl.caseID = '2abv1'
From what I read online, adding 'DefaultIfEmpty()' to the end of BookLinks should fix that, but it hasn't.
What am I doing wrong?
Thanks!
When using left join , you can try below code sample :
var plotData = (from nl in _context.BookList
join ql in _context.PlotList on nl.PlotId equals ql.PlotId
join qc in _context.PlotChoices on ql.PlotId equals qc.PlotId
join nk in _context.BookLinks on qc.ChoiceId equals nk.ChoiceId into Details
from m in Details.DefaultIfEmpty()
where nl.Id == ID
select new
{
}).ToList();
If the person you are searching is a CIA emplyee, take his CIAJobs.EmployerID, otherwise select People.ID
SELECT
case when CIAJobs.EmployeeID IS NULL then People.ID
else CIAJobs.EmployerID
end
FROM [FMO].[People] AS p
LEFT JOIN [FMO].[CIAJobs] j
ON (p.ID = j.[EmployeeID])
AND (j.[relationshipType] = '25a8d79d-377e-4108-8c92-0ef9a2e1ab63')
where p.ID = '1b66e032-94b2-e811-96e0-f48c508e38a2' // id of person you search for
OR
j.[EmployeeID] = '1b66e032-94b2-e811-96e0-f48c508e38a2' // id of person you search for
I tried doing this in Linq:
var a = from l in People
join x in CIAJobs
on l.Id equals x.EmployeeID && x.RelationshipTypeGuid equals Guid.Parse('25a8d79d-377e-4108-8c92-0ef9a2e1ab63')
into gcomplex
from xx in gcomplex.DefaultIfEmpty()
select (xx.EmployeeID == null) ? l.EmployeeId : x.EmployerID;
var b = a.ToList();
why does the query show an error because of this chunk: && x.RelationshipTypeGuid equals Guid.Parse('25a8d79d-377e-4108-8c92-0ef9a2e1ab63')
If I remove this part it shows no error.
Error is: operator && cannot be applied to operands of type Guid and Guid.
Can you help me correct the Linq query please logically and syntactically? Thank you.
You don't need join for multiple conditions in this scenario. Use this
var a = from l in People
join x in CIAJobs
.Where(z=>z.RelationshipTypeGuid
.Equals(Guid.Parse('25a8d79d-377e-4108-8c92-0ef9a2e1ab63')))
on l.Id equals x.EmployeeID
into gcomplex
from xx in gcomplex.DefaultIfEmpty()
select (xx.EmployeeID == null) ? l.EmployeeId : x.EmployerID;
var b = a.ToList();
But based on your problem statement this should do
var a = from l in People
join x in CIAJobs
on l.Id equals x.EmployeeID
into gcomplex
from xx in gcomplex.DefaultIfEmpty()
select (xx == null) ? l.EmployeeId : xx.EmployerID;
var b = a.ToList();
I have a query that I' struggling to convert to LINQ. I just can't get my head around the required nesting. Here's the query in SQL (just freehand typed):
SELECT V.* FROM V
INNER JOIN VE ON V.ID = VE.V_ID
WHERE VE.USER_ID != #USER_ID
AND V.MAX > (SELECT COUNT(ID) FROM VE
WHERE VE.V_ID = V.ID AND VE.STATUS = 'SELECTED')
The Closest I've come to is this:
var query = from vac in _database.Vacancies
join e in _database.VacancyEngagements
on vac.Id equals e.VacancyId into va
from v in va.DefaultIfEmpty()
where vac.MaxRecruiters > (from ve in _database.VacancyEngagements
where ve.VacancyId == v.Id && ve.Status == Enums.VacanyEngagementStatus.ENGAGED
select ve).Count()
...which correctly resolves the subquery from my SQL statement. But I want to further restrict the returned V rows to only those where the current user does not have a related VE row.
I've realised that the SQL in the question was misleading and whilst it led to technically correct answers, they weren't what I was after. That's my fault for not reviewing the SQL properly so I apologise to #Andy B and #Ivan Stoev for the misleading post. Here's the LINQ that solved the problem for me. As stated in the post I needed to show vacancy rows where no linked vacancyEngagement rows existed. The ! operator provides ability to specify this with a subquery.
var query = from vac in _database.Vacancies
where !_database.VacancyEngagements.Any(ve => (ve.VacancyId == vac.Id && ve.UserId == user.Id))
&& vac.MaxRecruiters > (from ve in _database.VacancyEngagements
where ve.VacancyId == vac.Id && ve.Status == Enums.VacanyEngagementStatus.ENGAGED
select ve).Count()
This should work:
var filterOutUser = <userId you want to filter out>;
var query = from vac in _database.Vacancies
join e in _database.VacancyEngagements
on vac.Id equals e.VacancyId
where (e.UserId != filterOutUser) && vac.MaxRecruiters > (from ve in _database.VacancyEngagements
where ve.VacancyId == vac.Id && ve.Status == Enums.VacanyEngagementStatus.ENGAGED
select ve).Count()
select vac;
I removed the join to VacancyEngagements but if you need columns from that table you can add it back in.
I am unable to execute the below linq.
var items( from p in Patients
join q in MURWorksheets on p.PatientId equals q.PatientId into step1
from s in step1.DefaultIfEmpty()
join t in MURWorksheetAnswers on s.MURWorksheetId equals t.MURWorksheetId into step2
from s2 in step2.DefaultIfEmpty()
select new {p.FirstName , Date = (s.MURDate == null ? DateTime.Now.Date : s.MURDate),
s2.MURQuestionnaireId,s2.MURExpctedAnswersId}).ToList();
Here is the sql for the same for your reference.
select a.FirstName,b.MURDate,c.MURQuestionnaireId,c.MURWorksheetAnswersID from Patients as a
left join MURWorksheet as b on a.PatientId = b.PatientId
left join MURWorksheetAnswers as c on b.MURWorksheetId = c.MURWorksheetId
You are missing an equals sign in your pasted code:
var items = (from p in Patients
join q in MURWorksheets on p.PatientId equals q.PatientId into step1
from s in step1.DefaultIfEmpty()
join t in MURWorksheetAnswers on s.MURWorksheetId equals t.MURWorksheetId into step2
from s2 in step2.DefaultIfEmpty()
select new {p.FirstName , Date = (s.MURDate == null ? DateTime.Now.Date : s.MURDate),
s2.MURQuestionnaireId,s2.MURExpctedAnswersId}).ToList();
I want to do a subselect with LINQ
What I have, but incorrect
var diretores = from item in db.San_PropostaConversa
join sc in db.San_Credenciada
on (item.Credenciada_Id) equals sc.Credenciada_Id
join sp in db.San_Proposta
on (item.Proposta_Id) equals sp.Proposta_Id
join si in db.San_Imovel
on (sp.Imovel_Id) equals si.Imovel_Id
join su in db.San_Usuario
on (item.Usuario_Id) equals su.Usuario_Id
where item.Proposta_Id == proposta
orderby item.DataHora descending
select new
{
sc.Apelido,
su.NomeCompleto,
su.DescricaoCargo1,
item.Comentario,
item.DataHora,
sp.Imovel_Id,
CredenciadaCaptadora_Id = si.Credenciada_Id,
item.Credenciada_Id,
(from item2 in db.San_Usuario
where item2.Cargo_Id == 9
&& item2.Excluido == 0
&& item2.Credenciada_Id == item.Credenciada_Id
select item2.Email)
};
In my SELECT statement, I want to recover an email column following some conditions that are specified in my WHERE clause.
Error
Invalid anonymous type member declarator. Anonymous type members must
be declared with a member assignment, simple name or member access
You have 2 problems in your linq expression:
You need to assign the result of the subquery to a member of the new anonymous type.
I think you only want to select 1 email with your subquery, so you need to use Single()/SingleOrDefault() or First()/FirstOrDefault().
Try this:
var diretores = from item in db.San_PropostaConversa
join sc in db.San_Credenciada
on item.Credenciada_Id equals sc.Credenciada_Id
join sp in db.San_Proposta
on (item.Proposta_Id) equals sp.Proposta_Id
join si in db.San_Imovel
on sp.Imovel_Id equals si.Imovel_Id
join su in db.San_Usuario
on item.Usuario_Id equals su.Usuario_Id
where item.Proposta_Id == proposta
orderby item.DataHora descending
select new
{
Apelido = sc.Apelido,
NomeCompleto = su.NomeCompleto,
DescricaoCargo1 = su.DescricaoCargo1,
Comentario = item.Comentario,
DataHora = item.DataHora,
Imovel_Id = sp.Imovel_Id,
CredenciadaCaptadora_Id = si.Credenciada_Id,
Credenciada_Id = item.Credenciada_Id,
Email = (from item2 in db.San_Usuario
where item2.Cargo_Id == 9
&& item2.Excluido == 0
&& item2.Credenciada_Id == item.Credenciada_Id
select item2.Email).FirstOrDefault()
};
Mostly this error occurring for unavailable assigning variable,
please try this
it will help you
var diretores = from item in db.San_PropostaConversa
join sc in db.San_Credenciada
on (item.Credenciada_Id) equals sc.Credenciada_Id
join sp in db.San_Proposta
on (item.Proposta_Id) equals sp.Proposta_Id
join si in db.San_Imovel
on (sp.Imovel_Id) equals si.Imovel_Id
join su in db.San_Usuario
on (item.Usuario_Id) equals su.Usuario_Id
where item.Proposta_Id == proposta
orderby item.DataHora descending
select new
{
Apelido=sc.Apelido,
NomeCompleto=su.NomeCompleto,
DescricaoCargo1=su.DescricaoCargo1,
Comentario=item.Comentario,
DataHora=item.DataHora,
Imovel_Id=sp.Imovel_Id,
CredenciadaCaptadora_Id = si.Credenciada_Id,
Credenciada_Id= item.Credenciada_Id,
result= (from item2 in db.San_Usuario
where item2.Cargo_Id == 9
&& item2.Excluido == 0
&& item2.Credenciada_Id == item.Credenciada_Id
select item2.Email)
};