Linq to sql Distinct after join - c#

I have a join query and i want to filter the result of this query by using distinct. I want to get only one of the shoes which has same brand, model, primary color and secondary color. How can i make this ? Here is my join query.
var query = from b in db.BrandTbls.AsQueryable()
join m in db.ShoeModelTbls on b.BrandID equals m.BrandID
join s in db.ShoeTbls on m.ModelID equals s.ModelID
join i in db.ShoeImageTbls on s.ShoeID equals i.ShoeID
where s.Quantity > 0
orderby m.ModelName
select new
{
s.ShoeID,
m.ModelName,
m.Price,
b.BrandName,
i.ImagePath
};

I found the solution. This query does approximately what i want to do
var query = from b in db.BrandTbls.AsQueryable()
join m in db.ShoeModelTbls on b.BrandID equals m.BrandID
join s in db.ShoeTbls on m.ModelID equals s.ModelID
join i in db.ShoeImageTbls on s.ShoeID equals i.ShoeID
group new {b,m,s,i} by new {b.BrandName,m.ModelName,m.Price,s.ShoeID,s.PrimaryColor,s.SecondaryColor,i.ImagePath} into g
select new {g.Key.ShoeID,g.Key.BrandName,g.Key.ModelName,g.Key.ImagePath,g.Key.Price};

Remove price from the output and use Distinct() like this:
var query = (from b in db.BrandTbls.AsQueryable()
join m in db.ShoeModelTbls on b.BrandID equals m.BrandID
join s in db.ShoeTbls on m.ModelID equals s.ModelID
join i in db.ShoeImageTbls on s.ShoeID equals i.ShoeID
where s.Quantity > 0
orderby m.ModelName
select new
{
s.ShoeID,
m.ModelName,
b.BrandName,
i.ImagePath
}).Distinct();

Related

Need help on Linq-to-SQL query (maybe nested query?)

I am asking for your help regarding a linq query to SQL.
Here is a part of the diagram of my database: https://imgur.com/xFBUm3q
My problem is in the following relationship: tbl_607_bottle and tbl_607_gaz_reporting, I can have several reportings for a bottle but reporting can only have one bottle.
I do this request but it's not satisfying.
var GazReportingWizardViewModel =
(from gr in db.tbl_607_gaz_reporting
join a in db.tbl_607_actors on gr.FK_ID_actors equals a.id
join bo in db.tbl_607_bottle on gr.FK_ID_bottle equals bo.ID
join loc in db.tbl_607_location on bo.FK_ID_location equals loc.ID
join cc in db.tbl_607_conformity_certificate on bo.FK_ID_conformity_certificate equals cc.ID
join j in db.tbl_607_join_bottle_gaz on bo.ID equals j.FK_ID_bottle
join g in db.tbl_607_gaz on j.FK_ID_gaz equals g.ID
join od in db.tbl_607_order_details on g.FK_ID_order_details equals od.ID
where loc.ID == Process
select new GazReportingWizardViewModel
{
bottle_conti_number = bo.bottle_conti_number,
pressure_value = gr.pressure_value,
reporting_date = gr.reporting_date,
first_name = gr.tbl_607_actors.first_name,
last_name = gr.tbl_607_actors.last_name,
expiration_date = cc.expiration_date,
content = od.content_comments
}).Distinct()
.OrderBy(t => t.reporting_date)
.ToList();
I want the last report on each bottle but it return all reports on each bottle.
Would you have an idea of ​​the solution?
Thank you for your time
Thank you so much!
I persisted in trying to solve the problem in a single query when the solution was so simple.
var GazReportingWizardViewModel = (from gr in db.tbl_607_gaz_reporting
join a in db.tbl_607_actors on gr.FK_ID_actors equals a.id
join bo in db.tbl_607_bottle on gr.FK_ID_bottle equals bo.ID
join loc in db.tbl_607_location on bo.FK_ID_location equals loc.ID
join cc in db.tbl_607_conformity_certificate on bo.FK_ID_conformity_certificate equals cc.ID
join j in db.tbl_607_join_bottle_gaz on bo.ID equals j.FK_ID_bottle
join g in db.tbl_607_gaz on j.FK_ID_gaz equals g.ID
join od in db.tbl_607_order_details on g.FK_ID_order_details equals od.ID
where loc.ID == Process
select new GazReportingWizardViewModel
{
bottle_conti_number = bo.bottle_conti_number,
pressure_value = gr.pressure_value,
reporting_date = gr.reporting_date,
first_name = gr.tbl_607_actors.first_name,
last_name = gr.tbl_607_actors.last_name,
expiration_date = cc.expiration_date,
content = od.content_comments
}).ToList();
var res = from element in GazReportingWizardViewModel
group element by element.bottle_conti_number
into groups
select groups.OrderByDescending(p => p.reporting_date).First();

Join list with table in linq

I have a problem. I get all data in var type variable and then want to apply a join with database table in code first approach. Facing problem, lot of search on internet and apply but failed.
var joinedData =
from menuGroup in _menuGroupMenusRepository.GetAll()
.Where(x => x.GroupId == input.GroupId)
join menus in _menuRepository.GetAll()
on menuGroup.MenuId equals menus.Id
join categSubcateg in _menuCategSubCategRepository.GetAll()
on menus.Id equals categSubcateg.MenuId
join categ in _menuCategoryRepository.GetAll()
on categSubcateg.CategoryId equals categ.Id
select new
{
CategoryId = categSubcateg.CategoryId,
CategoryName = categ.Category,
};
Now I want joinedData variable join with MainMenuSort table.
MainMenuSort table also have groupid and categoryid.
to perform join you just need to do as below
var q=(from jd in joinedData
join mms in dataContext.MainMenuSort
on jd.CategoryId equals mms.CategoryId
select jd).ToList();
if its datatable then
var q=(from jd in joinedData
join mms in dtMainMenuSort.AsEnumerable()
on jd.CategoryId equals mms.Field<int>("CategoryId")
select jd).ToList();

Complicated SQL query to Linq

I need to convert the following complicated sql query to Linq in C#:
Select Empleador.NombreComercial as Empresa,
Vacante.Puesto as Vacante,
Vacante.Actividades,
COUNT(Vacante.CveVacante) as Visitas
from Vacante
LEFT JOIN Empleador on Empleador.CveEmpleador=Vacante.CveEmpleador
LEFT JOIN VisitaVacante on Vacante.CveVacante = VisitaVacante.CveVacante
GROUP BY Empleador.NombreComercial,Vacante.Puesto, Vacante.Actividades,
Vacante.CveVacante HAVING COUNT(*) > 1 ORDER BY Visitas DESC
For the moment I already have the following:
var Visitas = (from tvacante in db.VacanteT
join tEmpleador in db.EmpleadorT on tvacante.CveEmpleador equals tEmpleador.CveEmpleador
join tVisitaVacante in db.VisitaVacanteT on tvacante.CveVacante equals tVisitaVacante.CveVacante
select new
{
Empresa = tEmpleador.NombreComercial,
Vacante = tvacante.Puesto,
tvacante.Actividades,
Visitas = tvacante.CveVacante
}).GroupBy( );
How can I add the COUNT(Vacante.CveVacante) as Visitas and also the
GROUP BY Empleador.NombreComercial,Vacante.Puesto, Vacante.Actividades,
Vacante.CveVacante HAVING COUNT(*) > 1 ORDER BY Visitas DESC
to my linq query? I can't find information about how to complete this. The tables are tvacante, templeador, and tvisitaVacante.
Try this:
var Visitas =(from tvacante in db.VacanteT
join tEmpleador in db.EmpleadorT on tvacante.CveEmpleador equals tEmpleador.CveEmpleador
join tVisitaVacante in db.VisitaVacanteT on tvacante.CveVacante equals tVisitaVacante.CveVacante
group new{tEmpleador.NombreComercial,tvacante.Puesto, tvacante.Actividades} by new {tEmpleador.NombreComercial,tvacante.Puesto, tvacante.Actividades} into g
where g.Count()>1
select new
{
Empresa = g.Key.tEmpleador.NombreComercial,
Vacante = g.Key.tvacante.Puesto,
Actividades= g.Key.tvacante.Actividades,
Visitas = g.Count()
}).OrderByDescending(e=>e.Visitas);
If you want to do it using only linq query syntax and not merging both syntax then you could also do this:
var Visitas = from tvacante in db.VacanteT
join tEmpleador in db.EmpleadorT on tvacante.CveEmpleador equals tEmpleador.CveEmpleador
join tVisitaVacante in db.VisitaVacanteT on tvacante.CveVacante equals tVisitaVacante.CveVacante
group new{tEmpleador.NombreComercial,tvacante.Puesto, tvacante.Actividades} by new {tEmpleador.NombreComercial,tvacante.Puesto, tvacante.Actividades} into g
where g.Count()>1
orderby g.Count() descending
select new
{
Empresa = g.Key.tEmpleador.NombreComercial,
Vacante = g.Key.tvacante.Puesto,
Actividades= g.Key.tvacante.Actividades,
Visitas = g.Count()
};

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()

Can't access the fields of non-grouping tables in linq

I'm trying to join few tables using LINQ and retrieve a data set. But my problem is when I group the tables, I cannot access the fields of the non grouped tables in the LINQ query. here is my sample code block. Please help
var query = from sb in db.Surfboards
join csb in db.CustomerSurfBoards on sb.SurfBoardID equals csb.SurfBoardID
join c in db.Customers on csb.CustomerID equals c.CustomerID
where c.IsActive
group new { sb,csb} by new {sb.ID, csb.ComponentId} into g
select new ReportModel()
{
ReceivedDate = g.First().Name,
Number = c.First().Number <------- this cannot be accessed
}
what I'm trying to achieve is something like this
select sb.Id, max(c.Number), cbs.Id from Surfboards as sb
inner join CustomerSurfBoards as cbs on sb.SurfBoardID = csb.SurfBoardID
inner join Customers as c on csb.CustomerID = c.CustomerID
group by sb.Id, csb.ComponentId
Try this:
var query = from sb in db.Surfboards
join csb in db.CustomerSurfBoards on sb.SurfBoardID equals csb.SurfBoardID
join c in db.Customers on csb.CustomerID equals c.CustomerID
where c.IsActive
select new {sb.id, c.number, cbs.componentid} into tmp
from t in tmp
group t by new {t.ID, t.ComponentId} into g
select new
{
g.Key.id, g.Key.componentid, number = g.Select(n=>n.number).OrderByDescending().FirstOrDefault()
}

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