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How to apply Right Outer Join using LINQ in C#?

I am facing issue to apply Right Outer Join in LINQ. I am trying to build the similar query in LINQ by converting from SQL query.
My correct SQL query
select *
from Table1 t1
inner join Table2 t2 on t1.Id = t2.FID and t1.CID = 20
right outer join Table3 t3 on t1.GID = t3.GID
var result = from t1 in Table1
join t2 in Table2
on t1.ID equals t2.FID into gr1
where t1.CID = 20
join t3 in Table3
on t1.GID equals t3.GID into gr2
from t3 in gr2.DefaultIfEmpty()
select new Details (){
}
return result.ToList();
}
My LINQ query is not working as expected to SQL query.

This is also discussed here
how to make a right join using LINQ to SQL & C#
var RightJoin = from adds in dc.EmpresaAddendas
join cats in CatAddendas
on adds.IDAddenda equals cats.IDAddenda into joined
from cats in joined.DefaultIfEmpty()
select new
{
Id = cats.IDAddenda,
Description = cats.Descripcion
};

Try this:
var result = from t1 in Table1
join t2 in Table2
on new { id = t1.ID; cid = t1.CID } equals new { id = t2.FID: cid = 20} into gr1
join t3 in Table3
on t1.GID equals t3.GID into gr2
from t123 in gr2.DefaultIfEmpty()
select new Details (){
}
return result.ToList();
}

As you're discovered, most LINQ providers don't offer support for a right join. DefaultIfEmpty translates into a LEFT join. As a result, you need to flip the logic of your query around a bit to turn the right join into a left one.
As far as the actual syntax, I've had success adopting more of an ANSI-82 syntax rather than worrying about the into temp2 from temp3 in temp2 syntax. Something along the lines of:
var result =
from t3 in Table3
from t1 in Table1.Where(temp1 => temp1.GID == t3.GID).DefaultIfEmpty()
join t2 in Table2 on t1ID equals t2.FID
where t1.CID == 20
select new Details{};

need to retrieve result set of Join Query

Need to retrieve result set of both tables but i am getting null value in it
var Items = from t1 in dbModal.Table1
join t2 in dbModal.Table2 on t1.id equals t2.Id
select new
{ t1, t2.column };
need to map above query like this
Select t1.*,t2.Column from T1
join T2 on T1.id=T2.Id

How to join table with multiple columns in linq?

I have following code in linq, what I am trying to do is joining tables with multiple columns of one table
//NOT A VALID CODE
from t1 in table1
join t2 in table2 on ((t1.ID equals t2.orderId) || (t1.ID equals t2.pickupId ))// how can I do this
...
...
How can I achieve this in Linq?

Use an anonymous type
from t1 in table1
join t2 in table2 on new { t1.ID, t1.pickupId } equals new { t2.ID, t2.pickupId }
...

var query = from t1 in table1
from t2 in table2
where t1.ID == t2.orderId || t1.ID == t2.pickupId
select new { t1, t2};

Select In Select Statement

What is an equivalent LINQ query to the following SQL query:
Select Id, Name
From Table1 tbl1
Where Id in ( Select Id From Table2)

You basically described an inner join with selection of rows from one table:
var result = from t1 in Table1
join t2 in Table2
on t1.Id equals t2.Id
select new{t1.Id, t1.Name};
Next SQL statement will be generated using EF and MS SQL:
SELECT t1.Id, t1.Name
FROM Table1 AS t1
INNER JOIN Table2 AS t2 ON t1.Id = t2.Id
Note, that if you are selecting non-unique items from Table2, you can potentially have duplicates in the result. Use next query to avoid this problem, cons: it loads all ids from Table2 into memory, pros: more time efficient. Checkout Felipes answer's, which is also quite good, but has it's own cons discussed in the comment section.
var table2Ids = new HashSet<int>(context.Table2.Select(t2 => t2.Id));
var result = context.Table1
.Where(t => table2Ids.Contains(t.Id))
.Select(t => new{t.Id, t.Name});

try using the Contains method:
var query = from c in db.Table1
where db.Table2.Select(x => x.Id).Contains(c.Id)
select new { c.Id, c.Name };
var result = query.ToList();

as performed query SQL in linq or lambda expression?

Good day to all,
I have the following problem
I have to convert the following query SQL to LINQ to SLQ or lambda expression:
SELECT T2.ID, SUM(T1.Importe) AS Importe, T3.ID, T3.Column_1,
T3.Column_2, T1.Column_3
FROM Tabla_1 T1
INNER JOIN Tabla_2 T2 on T1.ID = T2.ID
INNER JOIN Tabla_3 T3 on T2.ID = T3.ID
WHERE T1.ID in (LIST)
GROUP BY T2.ID, T3.ID, T3.Column_1, Column_2, T1.Column_3
where LIST is a List (12,15,18,19,...)
as performed in linq or lamnbda expression?
thks!

Here is the hint:
var result = ents.T1
.Where(x => list.Contains(x.Id))
.GroupBy(x => new
{
Id2 = x.T2.Id,
Id3 = x.T3.Id,
...
// etc group fields
})
.Select(x => new
{
Importe = x.Sum(i => i.Importe)
x.Key.Id2,
// other group fields
...
})
.ToArray();
I strongly suggest not to name columns and tables the way you did. Really)

I did not try, but it could look like that :
var result = (from t1 in dataContext.tabla_1
join t2 in dataContext.tabla_2 on t1.ID equals t2.ID
join t2 in dataContext.tabla_2 on t2.ID equals t3.ID
group t2 by t2.ID into g
where listIds.contains(t1.ID)
select new {g.ID, g.Sum(t => t.Importe), ...});