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LINQ query grouping without duplication of data

So I want to display an output that is group by two fields: SubsidiaryCode and AssetCreatedDate. My problem is it displays the grouping values redundantly.
I suspect it duplicates because of my Detail class.
What I want is:
But it displays like this:
LINQ query:
public DateTime FromDate { get; set; }
public DateTime ToDate { get; set; }
public IList<AssetListTemplate> List = new List<AssetListTemplate>();
public IList<AssetListTemplate> GetList()
{
using (var ctx = LinqExtensions.GetDataContext<NXpert.FixedAsset.DataAccess.FixedAssetDataContext>("AccountingDB"))
{
var list = (from x in ctx.DataContext.AssetRegistryEntities
where x.SubsidiaryCode2 != "" && x.SubsidiaryCode2.ToUpper().Contains("y-") && x.AssetCreatedDate>=FromDate && x.AssetCreatedDate <= ToDate
group new { x.SubsidiaryCode2, x.AssetCreatedDate,x.AssetCategoryID } by x into groupedList
select new AssetListTemplate
{
IsSelected = false,
SubsidiaryCode = groupedList.Key.SubsidiaryCode2,
AssetCreatedDate = groupedList.Key.AssetCreatedDate,
AssetCategory = groupedList.Key.AssetCategoryID
}
).OrderBy(x => x.SubsidiaryCode).ThenBy(y => y.AssetCreatedDate).ToList();
List = list;
foreach (var item in List)
{
var details = (from x in ctx.DataContext.AssetRegistryEntities
join y in ctx.DataContext.AssetCategoryEntities on x.AssetCategoryID equals y.AssetCategoryID
join z in ctx.DataContext.FixedAssetOtherInfoEntities on x.AssetCode equals z.AssetCode
where x.SubsidiaryCode2 == item.SubsidiaryCode
select new Details
{
AssetCode = x.AssetCode,
AssetCodeDesc = y.AssetCategoryDesc,
AssetDesc = x.AssetCodeDesc,
DepInCharge = z.DepartmentInCharge,
SerialNo = x.SerialNumber,
ModelNo = x.ModelNumber
}).ToList();
item.Details = details;
}
return List;
}
}
}
public class AssetListTemplate
{
public bool IsSelected { get; set; }
public string SubsidiaryCode { get; set; }
public DateTime? AssetCreatedDate { get; set; }
public string AssetCategory { get; set; }
public List<Details> Details { get; set; }
}
public class Details {
public string AssetCode { get; set; }
public string AssetCodeDesc { get; set; }
public string AssetDesc { get; set; }
public string DepInCharge { get; set; }
public string SerialNo { get; set; }
public string ModelNo { get; set; }
}
SQL Query:
SELECT Are_SubsidiaryCode2[SubsidiaryCode],Are_AssetCreatedDate[AssetCreatedDate],Are_AssetCategoryID[AssetCategory]
FROM E_AssetRegistry
WHERE Are_SubsidiaryCode2<>''
AND Are_SubsidiaryCode2 LIKE '%Y-%'
GROUP BY Are_SubsidiaryCode2
,Are_AssetCreatedDate
,Are_AssetCategoryID
ORDER BY AssetCreatedDate ASC

You don't seem to be using the grouping for any aggregate function , so you could make life simpler by just using distinct:
from x in ctx.DataContext.AssetRegistryEntities
where x.SubsidiaryCode2.Contains("y-") && x.AssetCreatedDate>=FromDate && x.AssetCreatedDate <= ToDate
select new AssetListTemplate
{
IsSelected = false,
SubsidiaryCode = groupedList.Key.SubsidiaryCode2,
AssetCreatedDate = groupedList.Key.AssetCreatedDate.Value.Date,
AssetCategory = groupedList.Key.AssetCategoryID
}
).Distinct().OrderBy(x => x.SubsidiaryCode).ThenBy(y => y.AssetCreatedDate).ToList();
Side note, you don't need to assign a list to a clas variable and also return it; I'd recommend just to return it. If you're looking to cache the results, make the class level var private, assign it and return it first time and just return it the second time (use the null-ness of the class level var to determine if the query has been run)
Expanding on the comment:
You don't need to store your data in a public property and also return it. Don't do this:
public class Whatever{
public string Name {get;set;}
public string GetName(){
var name = "John";
Name = name;
return name;
}
Typically we would either return it:
public class Whatever{
public string GetName(){
var name = MySlowDatabaseCallToCalculateAName();
return name;
}
//use it like:
var w = new Whatever();
var name = w.GetName();
Or we would store it:
public class Whatever{
public string Name {get;set;}
public void PopulateName(){
Name = MySlowDatabaseCallToCalculateAName();
}
//use it like
var w = new Whatever();
w.PopulateName();
var name = w.Name;
We might have something like a mix of the two if we were providing some sort of cache, like if the query is really slow and the data doesn't change often, but it is used a lot:
public class Whatever{
private string _name;
private DateTime _nameGeneratedAt = DateTime.MinValue;
public string GetName(){
//if it was more than a day since we generated the name, generate a new one
if(_nameGeneratedAt < DateTime.UtcNow.AddDays(-1)){
_name = MySlowDatabaseCallToCalculateAName();
_nameGeneratedAt = DateTime.UtcNow; //and don't do it again for at least a day
}
return _name;
}
This would mean that we only have to do the slow thing once a day, but generally in a method like "Get me a name/asset list/whatever" we wouldn't set a public property as well as return the thing; it's confusing for callers which one to use - they want the name; should they access the Name property or call GetName? If the property was called "MostRecentlyGeneratedName" and the method called "GenerateLatestName" it would make more sense - the caller can know they might call Generate..( first, and then they could use MostRecently.. - it's like a caching; the calling class can decide whether to get the latest, or reuse a recently generated one (but it does introduce the small headache of what happens if some other operation does a generate in the middle of the first operation using the property..)..
..but we probably wouldn't do this; instead we'd just provide the Generate..( method and if the caller wants to cache it and reuse the result, it can

Get objects whose property does not exist in enumerable

Multiple answers have led me to the following 2 solutions, but both of them do not seem to be working correctly.
What I have are 2 objects
public class DatabaseAssignment : AuditableEntity
{
public Guid Id { get; set; }
public string User_Id { get; set; }
public Guid Database_Id { get; set; }
}
public class Database : AuditableEntity
{
public Guid Id { get; set; }
public string Name { get; set; }
public string Server { get; set; }
public bool IsActive { get; set; }
public Guid DatabaseClientId { get; set; }
}
Now, the front-end will return all selected Database objects (as IEnumerable) for a given user. I am grabbing all current DatabaseAssignments from the database for the given user and comparing them to the databases by the Database.ID property. My goal is to find the DatabaseAssignments that I can remove from the database. However, my solutions keep returning all DatabaseAssignments to be removed.
if (databases != null)
{
var unitOfWork = new UnitOfWork(_context);
var userDatabaseAssignments = unitOfWork.DatabaseAssignments.GetAll().Where(d => d.User_Id == user.Id);
//var assignmentsToRemove = userDatabaseAssignments.Where(ud => databases.Any(d => d.Id != ud.Database_Id));
var assignmentsToRemove = userDatabaseAssignments.Select(ud => userDatabaseAssignments.FirstOrDefault()).Where(d1 => databases.All(d2 => d2.Id != d1.Database_Id));
var assignmentsToAdd = databases.Select(d => new DatabaseAssignment { User_Id = user.Id, Database_Id = d.Id }).Where(ar => assignmentsToRemove.All(a => a.Database_Id != ar.Database_Id));
if (assignmentsToRemove.Any())
{
unitOfWork.DatabaseAssignments.RemoveRange(assignmentsToRemove);
}
if (assignmentsToAdd.Any())
{
unitOfWork.DatabaseAssignments.AddRange(assignmentsToAdd);
}
unitOfWork.SaveChanges();
}

I think u are looking for an Except extension, have a look at this link
LINQ: Select where object does not contain items from list
Or other way is with contains see below Fiddler link :
https://dotnetfiddle.net/lKyI2F

Inner join not working when use equal with %, What an alternative way to use it like like %

I have Medals class, I call a service that return all Medal class fields except for the two fields ArabicName and ISOCode; Which I have to bring them from another table class "CountrysTBLs" , I made this join code:
The Medal class:
public class Medals {
public int bronze_count { get; set; }
public string country_name { get; set; }
public int gold_count { get; set; }
public string id { get; set; }
public int place { get; set; }
public int silver_count { get; set; }
public int total_count { get; set; }
public string ArabicName { get; set; } // this field not return by service
public string ISOCode { get; set; } // this field not return by service
}
The code:
var cntrs = db.CountrysTBLs.ToList();
List<Medals> objs = call_Service_Of_Medals_Without_ISOCode();
IEnumerable<Medals> query = from obj in objs
join cntry in cntrs on obj.country_name equals '%' + cntry.CommonName + '%'
select new Medals
{
ArabicName = cntry.ArabicName,
ISOCode = cntry.ISOCode,
country_name = obj.country_name,
place = obj.place,
gold_count = obj.gold_count,
silver_count = obj.silver_count,
bronze_count = obj.bronze_count,
total_count = obj.total_count
};
I get no result?!
How to fix that? Is there is any way to bring the two fields (ISOCode, ArabicName) without even use the inner join, and in same time best performance?

You want something like this to achieve LIKE functionality
List<Medals> medals = new List<Medals>();
var list = medals.Select(x => new
{
obj = x,
country = countries.FirstOrDefault(c => c.CommonName.Contains(x.country_name))
});
or something like this (if you want to just enrich each medal)
foreach (var medal in medals)
{
var country = countries.FirstOrDefault(c => c.CommonName.Contains(x.country_name));
medal.ISOCode = country.ISOCode;
medal.ArabicName = country.ArabicName;
}
Do note that this is not as performant as a Dictionary<string,Coutnry> of countries where the key is the country name, but as you need a LIKE comparison you would need to bring in a custom data structure such as Lucene index for fast lookups. But check first, if the lists are small enough, it probably won't be a problem. Otherwise, why not make the Medal.Country_Name and Country.Name the same? So you can do quick Dictionary (hashtable) lookups

Some value return null on Dapper Multi Mapping

I'm having a problem using Dapper.
I have a list of the Rubrica class that contains the field valore.
When I run a query with a JOIN and identify the agenda type, the valore field remains set to null
My two classes Rubrica and TipoAgenda
public class Rubrica // Same as table anagrafico_rubrica
{
public int id_rubrica { get; set; }
public string cod_anagrafica { get; set; }
public string descrizione_contatto { get; set; }
public TipoRubrica tipo { get; set; }
public string valore { get; set; }
}
public class TipoRubrica // Same as table anagrafico_tipo_rubrica
{
public int id_tipo_rubrica { get; set; }
public string descrizione_tipo_rubrica { get; set; }
}
I created a function that returns me a list of Agenda doing a JOIN with table anagrafico_tipo_rubrica
public List<Rubrica> GetAgendaAnagrafico(string codiceAnagrafico)
{
using (DatabaseConnection db = new DatabaseConnection())
{
const string query = #"SELECT * FROM anagrafico_rubrica JOIN anagrafico_tipo_rubrica ON tipo = id_tipo_rubrica WHERE cod_anagrafica = #anagrafico";
var parametri = new { anagrafico = codiceAnagrafico };
return db.con.Query<Rubrica, TipoRubrica, Rubrica>(query, (rubrica, tipo) => { rubrica.tipo = tipo; return rubrica; }, parametri, splitOn: "tipo").ToList();
}
}
Here you can see what the query returns
And here you see how int the Agenda list there is the value of valore set to null

You are splitting on tipo, which comes before valore in your query, so dapper is splitting the columns and thinking valore is for TipoRubrica instead of for Rubrica
Select the order of the fields explictly on your query
SELECT id_rubrica,
cod_anagrafica,
descrizione_contatto,
valore,
tipo, // <-- you are splitting here. columns above are for
// first type, columns below for second
id_tipo_rubrica,
descrizione_tipo_rubrica
FROM ...
So when you split on tipo, valore is before that, and it's mapped to the first type (Rubrica), instead of to the second (TipoRubrica)

How to set values of entities

I have module which is not mapped to database( sql server) and is only use to generate report.
public class Report
{
public int USERID { get; set; }
public DateTime DateToCal { get; set; }
public string Name { get; set; }
public string Position { get; set; }
public TimeSpan? Intime { get; set; }
public TimeSpan? OutTime { get; set; }
}
I generate a query and fill some properties(USERID, DateToCal, Name, Position, Intime) of Report and some properties of Report remains null ( as OutTime is null)
var query = .....;
Now what I want iterate on items of query( of type Report) and set value for null properties OutTime as
foreach(var items in query)
{
var outtime= from x in con.CHECKINOUTs
where x.USERID == items.USERID && EntityFunctions.TruncateTime(x.CHECKTIME) == EntityFunctions.TruncateTime(items.DateToCal && x.CHECKTYPE == "O"
select x.CHECKTIME
.Single();
items.OutTime= outtime.TimeOfDay;
}
Now problem is, on mousehover to items.OutTime with in foreach there appear value but if I out from foreach and mousehover to query there is still OutTime is null. There not appear value what I set. Is this is possible to set value of entities such way. Or what is my problem?
Thank you.

Save query results locally before iterating over them:
var query = ....ToList();
Looks like in your case query executed two times - first time when you are updating OutTime property, and second time when you are iterating over query items (either looking in debugger or displaying in UI). So, when query executed second time, you see completely new set of objects as query result (which have original null values of OutTime).
BTW Consider to use single JOIN query instead of making separate outtime query for each item in your main query.

Try code something like this:
public class Report
{
public int USERID { get; set; }
public DateTime DateToCal { get; set; }
public string Name { get; set; }
public string Position { get; set; }
private TimeSpan? _intime;
public TimeSpan Intime {
get { return _intime ?? new TimeSpan(0); }
set { _intime = value; }
}
private TimeSpan? _outTime;
public TimeSpan OutTime
{
get { return _outTime ?? new TimeSpan(0); }
set { _outTime = value; }
}
}