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How to handle linq join query when join on id is not available in the table c#

I am not trying to join my table using left outer join in LINQ where one of my join conditions does not satisfy. How can I still get the default record in my dataset? My SQL query runs perfectly fine but my join query is not returning the data.
Below is my SQL query where my left outer join works fine:
select
w.issueid as Issue
from worklog w
join jiraissue as j on w.issueid=j.ID
join issuetype AS ty ON ty.ID = j.issuetype
join project AS p on p.ID=j.PROJECT
left outer join customfieldvalue cfv on cfv.ISSUE = w.issueid
Below is my LINQ query in C# where if cfv.issue in the last join is not available in the table, I want to still return the default column.
var data = (from w in worklogs
join i in issuetypes on j.issuetype equals i.ID
join p in projects on j.PROJECT equals p.ID into table0
from c in table0.DefaultIfEmpty()
join cfv in customfieldvalues on w.issueid equals cfv.ISSUE into table1
from d in table1.DefaultIfEmpty()
{
IssueKey = l.Key.pkey + '-' + l.Key.issuenum,
Hours = l.Sum(w => w.timeworked)
}).ToList();
Any help is appreciated.
Thank you.

Using multiple LINQ statements with into , for the DefaultIfEmpty() of the left outer join not working

I am trying to use the "into" statement with DefaultIfEmpty() for the left outer join, but when I try to join to the 3rd collection, it doesn't like it (can't see /use it / find it )
It doesn't seem to like personRole on the line below
join roleTypes in roles on personRole.ContactRoleTypeId equals roleTypes.ContactRoleTypeId into r2
the query:
findPersonResultsViewModelNew =
from azed in findPersonViewModel.findPersonResultsViewModel
join personRole in personContactRoles on azed.PersonID equals personRole.PersonId into r1
join roleTypes in roles on personRole.ContactRoleTypeId equals roleTypes.ContactRoleTypeId into r2
from p in r1.DefaultIfEmpty()
from g in r2.DefaultIfEmpty()
select
//…. other code

Change the order of your statements. When doing left join, you must immediately follow the join with a new from...DefaultIfEmpty():
findPersonResultsViewModelNew =
from azed in findPersonViewModel.findPersonResultsViewModel
join personRole in personContactRoles on azed.PersonID equals personRole.PersonId into prj
from personRole in prj.DefaultIfEmpty()
join roleTypes in roles on personRole.ContactRoleTypeId equals roleTypes.ContactRoleTypeId into rtj
from roleTypes in rtj.DefaultIfEmpty()
select

LINQ query not returning expected results

I am trying to join three SQL tables in LINQ c# for the below SQL
SELECT
rpp.*
FROM dbo.Orgs ao
LEFT JOIN dbo.Afflia rpa
ON rpa.AccountId = ao.ID
INNER JOIN dbo.reports rpp
ON rpp.Id = rpa.reporttId
WHERE ao.Name like '%xyz%'
above query returns data but the equivalent LINQ query doesn't as in below
from a in context.Orgs
join aff in context.Afflia on a.ID equals aff.AccountId
join prescriber in context.Reports on aff.reportId equals prescriber.Id
where a.ORG_NAME.Contains("xyz")
May I know where the mistake is?

In LINQ you did INNER join but In SQL, you did LEFT join.
Try this instead:
from a in context.Orgs
join aff in context.Afflia on a.ID equals aff.AccountId into affs
from aff in affs.DefaultIfEmpty()
join prescriber in context.Reports on aff.reportId equals prescriber.Id
where a.ORG_NAME.Contains("xyz")

In your SQL you are doing a LEFT join to dbo.Afflia, but in your LINQ you are doing an inner join. You need to add "DefaultIfEmpty(), eg
from aff in context.Afflia.Where(join condition here).DefaultIfEmpty()

You could do:
var prescribers = (from a in context.Orgs
from aff in context.Afflia.Where(aff => aff.AccountId == a.ID)
from prescriber in context.Reports.Where(pres => pres.Id == aff.reportId)
where a.ORG_NAME.Contains("xyz")
select prescriber)
.ToList();

LINQ Left Join with multiple ON OR conditions

I'm sorry for telling that I've a little bit weak on LINQ, I always do write SQL query before I start working on the complicated LINQ.
I want to ask that how to convert this SQL Query into LINQ with LEFT JOIN with multiple ON conditons with the OR operator.,
m.MerchandiseId will be use for twice in ON condition
SELECT
*
FROM
Inbox AS i
INNER JOIN [User] AS u ON i.FromUserId = u.UserId
LEFT OUTER JOIN Merchandise AS m ON
u.MerchandiseId = m.MerchandiseId
OR
i.ToMerchantId = m.MerchandiseId
WHERE
i.ToCompanyId = 10
OR
i.FromCompanyId = 10
var message = (from i in db.Inbox
join u in db.User on i.FromUserId equals u.UserId
join m in db.Merchandise on u.MerchandiseId equals m.MerchandiseId //here I want to ON i.MerchantId = m.MerchandiseId, but it doesn't allow
where i.ToCompanyId == user.CompanyId || i.FromCompanyId == user.CompanyId
orderby i.CreatedAt descending
group m.MerchandiseId by new { m.MerchandiseId, m.MerchandiseName } into grp
select new
{
MerchandiseId = grp.Key.MerchandiseId,
MerchandiseName = grp.Key.MerchandiseName,
InboxMessage = (from e in db.Inbox
join us in db.User on e.FromUserId equals us.UserId
join mer in db.Merchandise on us.MerchandiseId equals mer.MerchandiseId
where mer.MerchandiseId == grp.Key.MerchandiseId
orderby e.CreatedAt descending
select e.InboxMessage).FirstOrDefault(),
CreatedAt = (from e in db.Inbox
join us in db.User on e.FromUserId equals us.UserId
join mer in db.Merchandise on us.MerchandiseId equals mer.MerchandiseId
where mer.MerchandiseId == grp.Key.MerchandiseId
orderby e.CreatedAt descending
select e.CreatedAt).FirstOrDefault(),
}).ToList();
The bottom LINQ Query I've write for it. However, I just can work on the left join with multiple ON clause in LINQ. Appreciate if someone would help me on this. Thanks!

I don't believe Linq supports the use of the OR operator with multiple columns, but that said, I wouldn't use OR even in SQL as it makes the join's intention unclear and it also obscures where the data originated from - it also isn't immediately clear what happens if there are multiple matches for each column. Instead I would JOIN twice on the different columns and let the projection-clause handle it:
SELECT
*
FROM
Inbox
INNER JOIN [User] AS u ON i.FromUserId = u.UserId
LEFT OUTER JOIN Merchandise AS userMerchant ON u.MerchandiseId = userMerchant.MerchandiseId
LEFT OUTER JOIN Merchandise AS inboxMerchant ON Inbox.ToMerchantId = inboxMerchant .MerchandizeId
WHERE
Inbox.ToCompanyId = 10
OR
Inbox.FromCompanyId = 10
This can then be translated into Linq using the LEFT OUTER JOIN approach ( How to implement left join in JOIN Extension method )
Note that if you're using Entity Framework then you don't need to worry about doing any of this at all! Just use Include:
var query = db.Inbox
.Include( i => i.User )
.Include( i => i.User.Merchandise )
.Include i => i.Merchandise )
.Where( i => i.ToCompanyId = 10 || i.FromCompanyId == 10 );

How can I write this query in LINQ

I have this query
SELECT t.NomeTipo, sum(v.QtdProduto)
FROM [dbo].[Vendas] AS V
RIGHT JOIN [dbo].[Produtos] AS P ON V.IdProduto = P.IdProduto
INNER JOIN [dbo].[Tipos] AS T ON P.IdTipo = T.IdTipo
group by t.NomeTipo
order by t.NomeTipo
I have tried this
var queryTipos = from vendas in repositorioVendas.Vendas
join produtos in repositorioProduto.Produtos.DefaultIfEmpty()
on vendas.IdProduto equals produtos.IdProduto
join tipos in repositorioTipo.Tipos
on produtos.IdTipo equals tipos.IdTipo
group vendas by new { tipos.NomeTipo, vendas.QtdProduto }
into novoGrupo
select new
{
NomeTipo = novoGrupo.Key.NomeTipo,
QtdProduto = novoGrupo.Sum(x => x.QtdProduto)
};
With this query I got only two results, but when I run straight from the database I get something like this:
Bebidas 16
Bolos 14
Frios 16
Pães 21

The trick is to realize that you can rewrite your query with a left join instead of a right join by swapping the order of the first two tables and that Linq doesn't have a way to really handle right joins. Also you're grouping was wrong.
var queryTipos = from produtos in repositorioProduto.Produtos
join vendas_pj in repositorioVendas.Vendas
on vendas_pj.IdProduto equals produtos.IdProduto into joined
from vendas in joined.DefaultIfEmpty()
join tipos in repositorioTipo.Tipos
on produtos.IdTipo equals tipos.IdTipo
group vendas by tipos.NomeTipo
into novoGrupo
select new
{
NomeTipo = novoGrupo.Key,
QtdProduto = novoGrupo.Sum(x => x.QtdProduto)
};
Basically a Left join in SQL
From TableA
Left Join TableB
On TableA.ID = TableB.ID
is done in Linq like this
from a in repo.TableA
join b_pj in repo.TableB
on a.ID equals b_pj.ID into joined
from b in joined.DefaultIfEmpty()