I have a table of orders. the status is on the soilorders which is joined to the orders.
I only want to return orders where the joined soilorder does not have status "Removed".
I had thought that
join sso in db.SoilSamplingOrders on ord.order_id equals sso.order_id
where sso.status.Equals("Removed")!=true
but then no records are returned!
thanks for any help (query below)
var query =
from ord in db.Orders
join sso in db.SoilSamplingOrders on ord.order_id equals sso.order_id
where sso.status.Equals("Removed")!=true
join cust in db.Customers on ord.customer_id equals cust.customer_id
select new Listing
{
assigned_to = sso.assigned_to,
company = cust.company,
order_id = ord.order_id,
order_created = ord.order_created,
customer_id = ord.customer_id,
order_created_by_employ_id = ord.order_created_by_employ_id,
first_farm_on_order = (from f in db.SoilSamplingSubJobs
where f.order_id == ord.order_id
select new ListingSubJob { first_farm_on_order = f.farm }).
AsEnumerable().First().first_farm_on_order,
total_fields = (from f in db.SoilSamplingSubJobs
where f.order_id == ord.order_id
select new { f.sssj_id }).AsEnumerable().Count(),
total_area = (float?) (from f in db.SoilSamplingSubJobs
where f.order_id == ord.order_id && f.area_ha != null
select f.area_ha ).Sum() ?? 0 ,
total_area_ph_density = (float?)(from f in db.SoilSamplingSubJobs
where f.order_id == ord.order_id && f.ph != null
select f.ph).Sum() ?? 0,
};
DOH! Just as nature abhors a vacuum, anything Null cannot be included in the select. Added values to the status field and bom it works.
Related
I am sql query us producing correct result, but when i'm doing the same in LINQ. Output is incorrect. Please let me know where my making mistake.
Following linq query that i created.
LINQ Query:
List<UserModel> Model = (from users in db.UserM
join ct in db.CustT on users.UserId equals ct.UserID into group1
from g1 in group1.DefaultIfEmpty()
join ti in db.TestIn on g1.TestId equals ti.TestID into group2
from g2 in group2.DefaultIfEmpty()
where (users.CustomerId==CustomerId) && (users.RoleId == 4) && (users.Status == 1)
group new
{
g2.TestInvitationID,
g2.TestID,
}
by new
{
users.FirstName,
users.CreatedOn,
users.Email,
users.UserId
} into group4
select new UserModel
{
Name = group4.Key.FirstName,
CreatedOn = group4.Key.CreatedOn,
EmailId = group4.Key.Email,
UserId = group4.Key.UserId,
NoOfTestTaken = group4.Select(x=>x.TestID).Distinct().Count(),
NoOfInvitationsSent = group4.Count(x => x.TestInvitationID != 0)
}).ToList();
SQL Query:
SELECT IsNull(COUNT(distinct TS.TestId),0) AS NoOfTests,
IsNull(COUNT(TS.TestInvitationID),0) AS NoOfInvitations,
UM.Email,
UM.UserId,
UM.FirstName,
UM.CreatedOn
FROM UserM as UM
left JOIN CustT AS CT
ON UM.UserId=CT.UserId
left JOIN TestIn AS TS
ON TS.TestId = CT.TestId
WHERE UM.CustomerId=41
AND UM.RoleId=4
and UM.[Status]=1
GROUP BY UM.UserId, UM.Email, UM.FirstName, UM.CreatedOn
Tables:
"UserM" - columns: UserId, Email, FirstName, CreatedOn
"CustT" - columns: TestId, UserId,
"TestIn" - columns: TestInvitationId, TestId
The difference between SQL COUNT(expr) and LINQ Count is that the former excludes NULL values, which produces a difference when used on right side of a left outer join with no matching records (SQL will produce 0 while LINQ 1). The closest LINQ equivalent is Count(expr != null).
So the direct translation of your SQL query would be like this (note that the generated SQL query could and most likely will be different):
(A side note: When converting SQL query to LINQ, it's good to use the same aliases to make it easier to see the mappings)
var query =
from um in db.UserMasters
join ct in db.CustTests on um.UserId equals ct.UserID
into ctGroup from ct in ctGroup.DefaultIfEmpty() // left outer join
join ts in db.TestInvitaions on ct.TestId equals ts.TestID
into tsGroup from ts in tsGroup.DefaultIfEmpty() // left outer join
where um.CustomerId == UserSession.CustomerId
&& um.RoleId == 4
&& um.Status == 1
group ts by new { um.UserId, um.Email, um.FirstName, um.CreatedOn } into g
select new UserModel
{
Name = g.Key.FirstName,
CreatedOn = g.Key.CreatedOn,
EmailId = g.Key.Email,
UserId = g.Key.UserId,
NoOfTestTaken = g.Where(ts => ts != null).Select(ts => ts.TestID).Distinct().Count(),
NoOfInvitationsSent = g.Count(ts => ts != null)
};
var result = query.ToList();
I suspect that the following row is the problem because is not the same like in your sql:
Linq:
NoOfInvitationsSent = group4.Count(x => x.TestInvitationID != 0)
SQL:
IsNull(COUNT(TS.TestInvitationID),0) AS NoOfInvitations
Due to counting items from a left join Linq should be instead:
NoOfInvitationsSent = group4.Where(i => i != null).Count()
To put it all together, with a bit of better formatting:
var model = (from users in db.UserMasters
join ct in db.CustTests on users.UserId equals ct.UserID into group1
from ct in group1.DefaultIfEmpty()
join ti in db.TestInvitaions on ct.TestId equals ti.TestID into group2
from ct in group2.DefaultIfEmpty()
where users.CustomerId == UserSession.CustomerId &&
users.RoleId == 4 &&
users.Status == 1
group new { ct.TestInvitationID, ct.TestID }
by new
{
users.FirstName,
users.CreatedOn,
users.Email,
users.UserId
} into grouping
select new UserModel
{
Name = grouping.Key.FirstName,
CreatedOn = grouping.Key.CreatedOn,
EmailId = grouping.Key.Email,
UserId = grouping.Key.UserId,
NoOfTestTaken = grouping.Where(i => i != null).Select(x => x.TestID).Distinct().Count(),
NoOfInvitationsSent = grouping.Where(i => i != null).Count()
}).ToList();
I am trying to select from multiple tables in an entity model. But there are two columns I would like to select and it's just not working out. The LINQ statement I have is:
var searchResult = from i in _imEntities.Issues
join dept in _imEntities.Departments
on i.Issued_to_dept equals dept.Dept_ID
where i.State == 1
select new {
i.ID_No,
i.Issue_Date,
Raised_By = dept.Dept_Name
.Where(i.Raised_by_Dept == dept.Dept_ID),
Issued_To = dept.Dept_Name
.Where(i.Issued_to_dept == dept.Dept_ID),
Details = i.Details
};
The column names are all correct, but I just can't get the dept_Names into the Raised_By and Issued_To fields. Is there another way to execute this?
Try this:
var query = from i in _imEntities.Issues
join dept_r in _imEntities.Departments
on i.Issued_to_dept equals dept_r.Dept_ID
join dept_i in _imEntities.Departments
on i.Issued_to_dept equals dept_i.Dept_ID
where i.State == 1
select new {
i.ID_No,
i.Issue_Date,
Raised_By = dept_r.Dept_Name,
Issued_To = dept_i.Dept_Name,
Details = i.Details
};
It's not clear what you are trying to achieve. But you definitely trying to apply where filter on single name string (also predicate syntax is not correct). Here is query which conditionally returns Dept_Name in Raised_By and Issued_To properties:
var query = from i in _imEntities.Issues
join dept in _imEntities.Departments
on i.Issued_to_dept equals dept.Dept_ID
where i.State == 1
select new {
i.ID_No,
i.Issue_Date,
Raised_By = (i.Raised_by_Dept == dept.Dept_ID) ? dept.Dept_Name : null,
Issued_To = (i.Issued_to_dept == dept.Dept_ID) ? dept.Dept_Name : null,
Details = i.Details
};
Problem: Am trying to rewrite this in Linq:
listOfUsersForReviewer is an IEnumerable<User>
int countOfGreenUsers = 0;
foreach (var user in listOfUsersForReviewer)
{
var u = (from reviewitems in context.ReviewItems
join groupaccountlinks in context.GroupAccountLinks on reviewitems.GroupAccountID equals groupaccountlinks.GroupAccountID
join reviews in context.Reviews on reviewitems.ReviewID equals reviews.ReviewID
join applications in context.Applications on reviews.ApplicationID equals applications.ApplicationID
join reviewers in context.Reviewers on applications.ResponsibleReviewerID equals reviewers.ReviewerID
join accounts in context.Accounts on groupaccountlinks.AccountID equals accounts.AccountID
join users in context.RBSUsers on accounts.UserID equals users.UserID
where
users.UserID == user.UserID &&
reviewers.FullyQualifiedLogin == fullyQualifiedLogin &&
reviews.ReviewStatusID == (byte)Enums.ReviewStatus.InProgress &&
reviewitems.ReviewItemStatusID == (byte)Enums.ReviewItemStatus.Unapproved
select reviewitems);
byte colour = (byte)Enums.UserStatusColour.Red;
if (u.Count() == 0)
{
colour = (byte)Enums.UserStatusColour.Green;
countOfGreenUsers++;
}
}
have tried to create an anonymous type, however this doesn't compile.
// select number of green users
var x = from user in listOfUsersForReviewer
from reviewitems in context.ReviewItems
join groupaccountlinks in context.GroupAccountLinks on reviewitems.GroupAccountID equals
groupaccountlinks.GroupAccountID
join reviews in context.Reviews on reviewitems.ReviewID equals reviews.ReviewID
join applications in context.Applications on reviews.ApplicationID equals applications.ApplicationID
join reviewers in context.Reviewers on applications.ResponsibleReviewerID equals
reviewers.ReviewerID
join accounts in context.Accounts on groupaccountlinks.AccountID equals accounts.AccountID
join users in context.RBSUsers on accounts.UserID equals users.UserID
where
users.UserID == user.UserID &&
reviewers.FullyQualifiedLogin == fullyQualifiedLogin &&
reviews.ReviewStatusID == (byte)Enums.ReviewStatus.InProgress &&
reviewitems.ReviewItemStatusID == (byte)Enums.ReviewItemStatus.Unapproved
select new
{
UserID = user.UserID,
CountOfGreen = reviewitems.Count()
};
Add grouping clause
var x = from user in listOfUsersForReviewer
from reviewitems in context.ReviewItems
join groupaccountlinks in context.GroupAccountLinks on reviewitems.GroupAccountID equals
groupaccountlinks.GroupAccountID
join reviews in context.Reviews on reviewitems.ReviewID equals reviews.ReviewID
join applications in context.Applications on reviews.ApplicationID equals applications.ApplicationID
join reviewers in context.Reviewers on applications.ResponsibleReviewerID equals
reviewers.ReviewerID
join accounts in context.Accounts on groupaccountlinks.AccountID equals accounts.AccountID
join users in context.RBSUsers on accounts.UserID equals users.UserID
where
users.UserID == user.UserID &&
reviewers.FullyQualifiedLogin == fullyQualifiedLogin &&
reviews.ReviewStatusID == (byte)Enums.ReviewStatus.InProgress &&
reviewitems.ReviewItemStatusID == (byte)Enums.ReviewItemStatus.Unapproved
group user by user.UserID into grouping
select new
{
UserID = grouping.Key,
CountOfGreen = grouping.Count()
};
I ended up rethinking me logic and split this query into 2 simpler ones.
Tools I used were: SQL Server Management Studio (graphical representation), Linqer and potentially Linqpad
And writing the query in English helped a lot.
I have one Linq Query. When I run the query, Only for 10 records its taking 13 seconds to extract the data to the model. I need to know the query which I wrote is good for performance or not. Please guide me what i am doing wrong.
Code
var stocktakelist = (from a in Db.Stocktakes
select new ExportStock
{
Id = a.Id,
ItemNo = a.ItemNo,
AdminId = (from admin in Db.AdminAccounts where admin.Id == a.Id select admin.Name).FirstOrDefault(),
CreatedOn = a.CreatedOn,
Status = (from items in Db.Items where items.ItemNo == a.ItemNo select items.ItemStatu.Description).FirstOrDefault(),
Title = (from tit in Db.BibContents where tit.BibId == (from bibs in Db.Items where bibs.ItemNo == a.ItemNo select bibs.BibId).FirstOrDefault() && tit.TagNo == "245" && tit.Sfld == "a" select tit.Value).FirstOrDefault() // This line of Query only makes the performance Issue
}
).ToList();
Thanks
The reason this is so slow is because it is running the 3 inner LINQ statements for every item in the outer LINQ statement.
Using LINQ joins will run only 4 queries and then link them together, which is faster.
To find out how to join, there are plenty of resources on the Internet depending on the type of LINQ you are using.
If you're retrieving this data from a SQL server, perhaps consider doing this intensive work in SQL - this is what SQL was designed for and it's much quicker than .NET. EDIT: As highlighted below, the work is done in SQL if using LINQ to SQL/Entities and using the correct join syntax.
I was trying to create the corresponding query with some joins for practice.
I cannot test it and i'm not 100% sure that this query will you get the result
you are hoping for but maybe at least it will give you a hint on how to write
joins with linq.
from a in Db.Stocktakes
join admin in Db.AdminAccounts
on a.Id equals admin.Id
into adminJoinData
from adminJoinRecord in adminJoinData.DefaultIfEmpty( )
join items in Db.Items
on a.ItemNo equals items.ItemNo
into itemsJoinData
from itemsJoinRecord in itemsJoinData.DefaultIfEmpty( )
join title in Db.BibContents
(
from subQuery in Db.BibContents
where subQuery.TagNo == "245"
where subQuery.Sfld == "a"
select subquery
)
on title.BibId equals itemsJoinRecord.BidId
into titleJoinData
from titleJoinRecord in titleJoinData.DefaultIfEmpty( )
select new ExportStock( )
{
Id = a.Id,
ItemNo = a.ItemNo,
AdminId = adminJoinRecord.Name,
CreatedOn = a.CreatedOn,
Status = itemsJoinRecord.ImemStatu.Description,
Title = titleJoinRecord.Value
}
As others have said, you should use Left Outer Joins in your LINQ just as you would if writing it in SQL.
Your query above will end up looking roughly like this once converted (this is untested, but gives the basic idea):
var a = from a in Db.Stocktakes
join admin in Db.AdminAccounts on admin.Id equals a.Id into tmpAdmin
from ad in tmpAdmin.DefaultIfEmpty()
join item in Db.Items on item.ItemNo equals a.ItemNo into tmpItem
from it in tmpItem.DefaultIfEmpty()
join title in Db.BibContents on bib.BibId equals items.BibId into tmpTitle
from ti in tmpTitle.DefaultIfEmpty()
where ti.TagNo == "245"
&& ti.Sfld == "a"
select new ExportStock
{
Id = a.Id,
ItemNo = a.ItemNo,
AdminId = ad == null ? default(int?) : ad.Id,
CreatedOn = a.CreatedOn,
Status = it == null ? default(string) : it.ItemStatus.Description,
Title = ti == null ? default(string) : ti.Value
};
Using lambda expressions your query will look like this:
Db.Stocktakes
.Join(Db.AdminAccounts, a => a.Id, b => b.Id, (a,b) => new { a, AdminId = b.Name })
.Join(Db.Items, a => a.ItemNo, b => b.ItemNo, (a,b) => new { a, Status = b.ItemStatus.Description, BidId = b.BibId })
.Join(Db.BibContents, a => a.BibId, b => b.BibId, (a,b) => new { a, Value = b.Value, TagNo = b.TagNo, Sfld = b.Sfld })
.Where(a => a.TagNo == "245" && a.Sfld == "a")
.Select(a =>
new ExportStock { Id = a.Id,
ItemNo = a.ItemNo,
AdminId = a.AdminId,
CreatedOn = a.CreatedOn,
Status = a.Status,
Title = a.Value
}
).ToList();
I want to do a subselect with LINQ
What I have, but incorrect
var diretores = from item in db.San_PropostaConversa
join sc in db.San_Credenciada
on (item.Credenciada_Id) equals sc.Credenciada_Id
join sp in db.San_Proposta
on (item.Proposta_Id) equals sp.Proposta_Id
join si in db.San_Imovel
on (sp.Imovel_Id) equals si.Imovel_Id
join su in db.San_Usuario
on (item.Usuario_Id) equals su.Usuario_Id
where item.Proposta_Id == proposta
orderby item.DataHora descending
select new
{
sc.Apelido,
su.NomeCompleto,
su.DescricaoCargo1,
item.Comentario,
item.DataHora,
sp.Imovel_Id,
CredenciadaCaptadora_Id = si.Credenciada_Id,
item.Credenciada_Id,
(from item2 in db.San_Usuario
where item2.Cargo_Id == 9
&& item2.Excluido == 0
&& item2.Credenciada_Id == item.Credenciada_Id
select item2.Email)
};
In my SELECT statement, I want to recover an email column following some conditions that are specified in my WHERE clause.
Error
Invalid anonymous type member declarator. Anonymous type members must
be declared with a member assignment, simple name or member access
You have 2 problems in your linq expression:
You need to assign the result of the subquery to a member of the new anonymous type.
I think you only want to select 1 email with your subquery, so you need to use Single()/SingleOrDefault() or First()/FirstOrDefault().
Try this:
var diretores = from item in db.San_PropostaConversa
join sc in db.San_Credenciada
on item.Credenciada_Id equals sc.Credenciada_Id
join sp in db.San_Proposta
on (item.Proposta_Id) equals sp.Proposta_Id
join si in db.San_Imovel
on sp.Imovel_Id equals si.Imovel_Id
join su in db.San_Usuario
on item.Usuario_Id equals su.Usuario_Id
where item.Proposta_Id == proposta
orderby item.DataHora descending
select new
{
Apelido = sc.Apelido,
NomeCompleto = su.NomeCompleto,
DescricaoCargo1 = su.DescricaoCargo1,
Comentario = item.Comentario,
DataHora = item.DataHora,
Imovel_Id = sp.Imovel_Id,
CredenciadaCaptadora_Id = si.Credenciada_Id,
Credenciada_Id = item.Credenciada_Id,
Email = (from item2 in db.San_Usuario
where item2.Cargo_Id == 9
&& item2.Excluido == 0
&& item2.Credenciada_Id == item.Credenciada_Id
select item2.Email).FirstOrDefault()
};
Mostly this error occurring for unavailable assigning variable,
please try this
it will help you
var diretores = from item in db.San_PropostaConversa
join sc in db.San_Credenciada
on (item.Credenciada_Id) equals sc.Credenciada_Id
join sp in db.San_Proposta
on (item.Proposta_Id) equals sp.Proposta_Id
join si in db.San_Imovel
on (sp.Imovel_Id) equals si.Imovel_Id
join su in db.San_Usuario
on (item.Usuario_Id) equals su.Usuario_Id
where item.Proposta_Id == proposta
orderby item.DataHora descending
select new
{
Apelido=sc.Apelido,
NomeCompleto=su.NomeCompleto,
DescricaoCargo1=su.DescricaoCargo1,
Comentario=item.Comentario,
DataHora=item.DataHora,
Imovel_Id=sp.Imovel_Id,
CredenciadaCaptadora_Id = si.Credenciada_Id,
Credenciada_Id= item.Credenciada_Id,
result= (from item2 in db.San_Usuario
where item2.Cargo_Id == 9
&& item2.Excluido == 0
&& item2.Credenciada_Id == item.Credenciada_Id
select item2.Email)
};