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order by len() but in linq with c#

this is my query in sql server and everything works fine
select * from DetalleNotas
order by len(ColProduct), ColProduct
PROCT1
PROCT2
PROCT3
PROCT4
PROCT5
PROCT6
PROCT7
PROCT8
PROCT9
PROCT10
but i want my query in linq c#
I tried this and it does not work
var product = (from d in db.Product
orderby len(d.ColProduct), d.ColProduct
select new
{
product= d.product
});
the name "len" does not exist in the real context
only this query works
var product = (from d in db.DetalleNotas
orderby d.ColProduct
select new
{
product= d.product
});
This is the result of my functional query
PROCT1
PROCT10
PROCT2
PROCT3
PROCT4
PROCT5
PROCT6
PROCT7
PROCT8
PROCT9

Remember that in C# Linq code, everything is still C#. As you're working with strings you need to order by string.Length. For example:
var results = from d in db.DetalleNotas
orderby d.ColProduct.Length
select d;

You could order it by the number on the end of your strings:
var result = db.DetalleNotas.OrderBy(d => Convert.ToInt32(d.ColProduct.Substring(5)))
.ToArray();

convert SQL query to Linq

Could somebody assist me in converting a sql query into LINQ ? I well understand SQL queries, but I am a novice in Linq. Thank you so much for help me.
SELECT
subConsulta."NitIps",
subConsulta."NumFactura",
COUNT(*)
FROM
(SELECT
DISTINCT acf."NitIps",
acf."NumFactura",
acf."TipoSoporte"
FROM
"t_ArchivoCentralFacturacion" AS acf
inner join "t_TRCompartaTiposDocumentalesAC" AS ctd
on
acf."TipoSoporte"= ctd."Id"
GROUP BY
acf."NitIps",
acf."NumFactura",
acf."TipoSoporte")as subConsulta
GROUP BY
subConsulta."NitIps",
subConsulta."NumFactura"
ORDER BY
subConsulta."NitIps",
subConsulta."NumFactura"

If you map your tables to entities it looks like follow:
var first = from archivoCentralFacturacion in ArchivoCentralFacturacions
group archivoCentralFacturacion by new {
c.NitIps,
c.NumFactura,
c.TipoSoporte
} into subConsulta
select subConsulta;
var result = (from f in first
group f by new {
f.NitIps,
f.NumFactura
} into r
select new {
NitIps = r.NitIps,
NumFactura = r.NumFactura,
ResultCount = r.Count()
}).OrderBy(x => x.NitIps).ThenBy(x => x.NumFactura);

LINQ Projected Filtering C#

I want to filter my LINQ query based on an included table but am having some trouble.
Here is the original statement, which works:
return
this.ObjectContext.People.
Include("Careers").
Include("Careers.Titles").
Include("Careers.Titles.Salaries");
Now I'm trying to filter on Careers using projected filtering but am having trouble. It compiles but it leaves out the Titles and Salaries tables, which causes runtime errors, and I can't seem to add those tables back in:
var query1 = (
from c in
this.ObjectContext.People.
Include("Careers").
Include("Careers.Titles").
Include("Careers.Titles.Salaries")
select new
{
c,
Careers = from Careers in c.Careers
where Careers.IsActive == true
select Careers
});
var query = query1.AsEnumerable().Select(m => m.c);
return query.AsQueryable();
How can I include the titles and salaries tables in the filtered query?

You can simplify your query considerably, which should resolve your issue. I'm assuming that you want all people with at least 1 active career:
var query =
from c in
this.ObjectContext.People.
Include("Careers").
Include("Careers.Titles").
Include("Careers.Titles.Salaries")
where c.Careers.Any(c => c.IsActive);
return query;

I would try something like,
var query = from p in ObjectContext.People
join c in ObjectContext.Careers on p equals c.Person
where c.IsActive
select p;

Entity Framework select distinct name

How can I do this SQL query with Entity Framework?
SELECT DISTINCT NAME FROM TestAddresses

Using lambda expression..
var result = EFContext.TestAddresses.Select(m => m.Name).Distinct();
Another variation using where,
var result = EFContext.TestAddresses
.Where(a => a.age > 10)//if you have any condition
.Select(m => m.name).Distinct();
Another variation using sql like syntax
var result = (from recordset
in EFContext.TestAddresses
.where(a => a.city = 'NY')//if you have any condition
.select new
{
recordset.name
}).Distinct();

Try this:
var results = (from ta in context.TestAddresses
select ta.Name).Distinct();
This will give you an IEnumerable<string> - you can call .ToList() on it to get a List<string>.

The way that #alliswell showed is completely valid, and there's another way! :)
var result = EFContext.TestAddresses
.GroupBy(ta => ta.Name)
.Select(ta => ta.Key);
I hope it'll be useful to someone.

DBContext.TestAddresses.Select(m => m.NAME).Distinct();
if you have multiple column do like this:
DBContext.TestAddresses.Select(m => new {m.NAME, m.ID}).Distinct();
In this example no duplicate CategoryId and no CategoryName i hope this will help you

Entity-Framework Select Distinct Name:
Suppose if you are using Views in which you are using multiple tables and you want to apply distinct in that case first you have to store value in variable & then you can apply Distinct on that variable like this one....
public List<Item_Img_Sal_VIEW> GetItemDescription(int ItemNo)
{
var Result= db.Item_Img_Sal_VIEW.Where(p => p.ItemID == ItemNo).ToList();
return Result.Distinct().ToList();
}
Or you can try this Simple Example
Public Function GetUniqueLocation() As List(Of Integer)
Return db.LoginUsers.Select(Function(p) p.LocID).Distinct().ToList()
End Function

use Select().Distinct()
for example
DBContext db = new DBContext();
var data= db.User_Food_UserIntakeFood .Select( ).Distinct();

In order to avoid ORDER BY items must appear in the select list if SELECT DISTINCT error, the best should be
var results = (
from ta in DBContext.TestAddresses
select ta.Name
)
.Distinct()
.OrderBy( x => 1);

Entity-Framework Select Distinct Name:
Suppose if you are want every first data of particular column of each group ;
var data = objDb.TableName.GroupBy(dt => dt.ColumnName).Select(dt => new { dt.Key }).ToList();
foreach (var item in data)
{
var data2= objDb.TableName.Where(dt=>dt.ColumnName==item.Key).Select(dt=>new {dt.SelectYourColumn}).Distinct().FirstOrDefault();
//Eg.
{
ListBox1.Items.Add(data2.ColumnName);
}
}

IN Operator in where clause

List<HelprClass.Organizer> org =
( from EventOrg in cntx.EventOrganizer
from MstrOrg in cntx.Organizer
where EventOrg.OrganizerID == MstrOrg.OrganizerID
Select new HelprClass.Organizer
{
OrganizerName = MstrOrg.OrganizerName
}).ToList()
This work fine now i want to use IN Opeartor in the above Query.
in the EventOrganizer I have EventID now i want to select only Event ID exsist in EventOrganizer collection
I have EventID another var varibale
Var EventID= From EvntID in Evetn Select new {ID= EvntID.EventID};
Something like this
where
EventOrg.OrganizerID == MstrOrg.OrganizerID
&& EventOrg.EventID in EventID.ID
How I can achive this ?
I will appreciate your help

Try this:
var EventIDs = from EvntID in Event select EvntID.EventID;
var org = (from EventOrg in cntx.EventOrganizer
from MstrOrg in cntx.Organizer
where EventOrg.OrganizerID == MstrOrg.OrganizerID
select new {E=EventOrg, M=MstrOrg}
).ToList();
org = org
.Where(o => EventIDs.Contains(o.E.EventID) )
.Select(o => new HelprClass.Organizer
{
OrganizerName = o.M.OrganizerName
}
);

If you are using Entity Framework you can not use a Contains statement, which would be an easy solution in Linq. SO if it's just Linq 2 Entities, use a where clause like "where EventId.Contains(EventOrg.Id)"
If you are indeed using Entity Framework you will have to build an or expression based on the Id's in the EventID Collection.