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C# linq query with where subquery for each property

I have this table:
I want to do a linq query where I'll get each property value based on the adminfilterfieldid.
I have this so far:
newDto = from d in DbContext.AdminFilterItems
where d.AdminFilterID == filterId
select new ReservationDto
{
BookingDate = d.Value
};
Now since BookingDate is AdminFilterFieldId is 2, I was hoping I can do something like BookingDate = d.Value.Where(s => s.AdminFilterFieldID = 3) or null in case there is no value for that adminfilterfieldid.
I want to do this for all the fields for that adminfilterid.
Is that achievable somehow with this kind of query or will I need to do multiple queries?

It looks simple enough just another clause in your where.
from d in DbContext.AdminFilterItems
where d.AdminFilterID == filterId
&& d.AdminFilterFieldID = 3
select new ReservationDto
{
BookingDate = d.Value
};
If you need to filter it on multiple values just keep your initial query and run other filters on it then do your projection (select).
var qry = from d in DbContext.AdminFilterItems
where d.AdminFilterID == filterId
// Filter 1
qry.Where(d => d.AdminFilterFieldID = 3).Select(d => new ReservationDto
{
BookingDate = d.Value
});
// Filter 2
qry.Where(d => d.AdminFilterFieldID = 2).Select(d => new ReservationDto
{
BookingDate = d.Value
});

Linq to SQL grouping with embedded lists causes too many queries

I am developing a query to grab and join some SQL tables in C# and am having some trouble with grouping and enumerables within the dataset. My query is below. This gives me the data in the format I'm looking for, but it takes way too long when I try to add the enumerated list as indicated below. When I look under the hood I can see it is executing way too many SQL queries. I'd like to get it to just one. Using LinqPad:
void Main()
{
var nightlyRuns = (from a in LoadTestSummaries
join b in LoadTestTestSummaryData
on a.LoadTestRunId equals b.LoadTestRunId
where a.TargetStack == "LoadEnv" &&
a.TestGuid != null &&
a.StartTime != null &&
a.LoadTestRunId != null
orderby a.StartTime
group new {a, b} by new
{
a.TestGuid,
a.Name,
a.Description,
a.StartTime,
a.Duration,
a.NumAgents,
a.NumHosts,
a.PassFail,
a.ResultsFilePath,
a.Splunk
}
into g
let scenarioStart = g.Min(s => s.a.StartTime) ?? g.Min(s => s.a.DateCreated)
let testCases = g.Select(s => s.b)
orderby scenarioStart
select new
{
TestGuid = g.Key.TestGuid,
ScenarioRun = new
{
Name = g.Key.Name,
Description = g.Key.Description,
StartTime = scenarioStart,
Duration = g.Key.Duration,
NumAgents = g.Key.NumAgents,
NumHosts = g.Key.NumHosts,
Result = g.Key.PassFail,
ResultsFilePath = g.Key.ResultsFilePath,
SplunkLink = g.Key.Splunk,
// PROBLEM: Causes too many queries:
TestRuns = from t in testCases select t.TestCaseId
}
}).ToLookup(g => g.TestGuid, g => g.ScenarioRun);
nightlyRuns["ba593f66-695f-4fd1-99c3-71253a2e4981"].Dump();
}
The "TestRuns" line is causing the excessive queries. Any idea what I am doing wrong here?
Thanks for any insight.

Tough answer to test but I think we can avoid the grouping and multiple queries with something like this: (https://msdn.microsoft.com/en-us/library/bb311040.aspx)
var nightlyRuns = (from a in LoadTestSummaries
join b in LoadTestTestSummaryData
on a.LoadTestRunId equals b.LoadTestRunId
where a.TargetStack == "LoadEnv" &&
a.TestGuid != null &&
a.StartTime != null &&
a.LoadTestRunId != null
into testGroup
select new
{
TestGuid = a.TestGuid,
ScenarioRun = new
{
Name = a.TestGuid,
Description = a.Description,
StartTime = a.StartTime ?? a.DateCreated,
Duration = a.Duration,
NumAgents = g.Key.NumAgents,
NumHosts = a.NumHosts,
Result = a.PassFail,
ResultsFilePath = a.ResultsFilePath,
SplunkLink = a.Splunk,
// PROBLEM: Causes too many queries:
TestRuns =testGroup
}
}).OrderBy(x=>x.StartTime).ToLookup(x => x.TestGuid, x => x.ScenarioRun);
nightlyRuns["ba593f66-695f-4fd1-99c3-71253a2e4981"].Dump();

Linq query DateTime.Date.DayOfWeek

Trying to get only Thursdays of 1 year back
using (var context = new Context1())
{
// Get 1 year back only Thursday
var oneYearEarlier = DateTime.Now.AddYears(-1);
var query = (from c in context.Daily25Data
where c.Date > oneYearEarlier && c.Date.DayOfWeek == DayOfWeek.Thursday
select c).ToList();
Console.WriteLine(query);
}
and getting
Additional information: The specified type member 'DayOfWeek' is not
supported in LINQ to Entities. Only initializers, entity members, and
entity navigation properties are supported.

This is a clever solution using EntityFunctions.DiffDays
from his post:
DateTime firstSunday = new DateTime(1753, 1, 7);
var bookings = from b in this.db.Bookings
where EntityFunctions.DiffDays(firstSunday, b.StartDateTime) % 7 == 1
select b;

LINQ will not recognize the second part of your query into SQL. You need to break your query up in order to perform the filter.
using (var context = new algoventurelab_db1Context())
{
// Go one year back from current date
var startDate = DateTime.Today.AddYears(-1);
// This will get all dates in context greater than start date.
var query1 = (from c in context.Daily25Data
where c.Date >= startDate
select c).AsEnumerable();
//this will filter only thurdays
var query = from c in query1
where c.Date.DayOfWeek == DayOfWeek.Thursday
select c).ToList();
Console.WriteLine(query);
}

Returning List value using linq C#

Actually I want to return the data from different lists based on Date. When i'm using this i'm getting data upto #Var result but i'm unnable to return the data. The issue with this is i'm getting error #return result. I want to return the data #return result. I'm using Linq C#. Can anyone help me out?
public List<CustomerWiseMonthlySalesReportDetails> GetAllCustomerWiseMonthlySalesReportCustomer()
{
var cbsalesreeport = (from cb in db.cashbilldescriptions
join c in db.cashbills on cb.CashbillId equals c.CashbillId
join p in db.products on cb.ProductId equals p.ProductId
select new
{
Productamount = cb.Productamount,
ProductName = p.ProductDescription,
CashbillDate = c.Date
}).AsEnumerable().Select(x => new ASZ.AmoghGases.Model.CustomerWiseMonthlySalesReportDetails
{
Productdescription = x.ProductName,
Alldates = x.CashbillDate,
TotalAmount = x.Productamount
}).ToList();
var invsalesreeport = (from inv in db.invoices
join invd in db.invoicedeliverychallans on inv.InvoiceId equals invd.InvoiceId
select new
{
Productamount = invd.Total,
ProductName = invd.Productdescription,
InvoiceDate = inv.Date
}).AsEnumerable().Select(x => new ASZ.AmoghGases.Model.CustomerWiseMonthlySalesReportDetails
{
Productdescription = x.ProductName,
Alldates = x.InvoiceDate,
TotalAmount = x.Productamount
}).ToList();
var abc = cbsalesreeport.Union(invsalesreeport).ToList();
var result = (from i in abc
group i by new { Date = i.Alldates.ToString("MMM"), Product = i.Productdescription } into grp
select new { Month = grp.Key, Total = grp.Sum(i => i.TotalAmount) });
**return result;**
}

You can either convert your result to a List before returning it using return result.ToList() or make your method return an IEnumerable<CustomerWiseMonthlySalesReportDetails> instead of List.
As your result is an enumeration of anonymous types you have to convert them to your CustomerWiseMonthlySalesReportDetails-type first:
select new CustomerWiseMonthlySalesReportDetails{ Month = grp.Key, Total = grp.Sum(i => i.TotalAmount) });
Assuming your type has exactly the members returned by the select.
EDIT: So your code should look like this:
var result = (from i in abc
group i by new { Date = i.Alldates.ToString("MMM"), Product = i.Productdescription } into grp
select new CustomerWiseMonthlySalesReportDetails{ Month = grp.Key, Total = grp.Sum(i => i.TotalAmount) });
return result.ToList();

You can assume Alldates property if is date of one of groups that month of date is in right place:
var result = (from i in abc
group i by new { Date = i.Alldates.ToString("MMM"), Product = i.Productdescription }
into grp
select new CustomerWiseMonthlySalesReportDetails{
Productdescription = grp.Key.Product,
TotalAmount = grp.Sum(i => i.TotalAmount),
Alldates =grp.First(i=>i.Alldates ) })
.ToList();

Linq to select data from one table not in other table

Hi i have the following code to select data from one table not in other table
var result1 = (from e in db.Users
select e).ToList();
var result2 = (from e in db.Fi
select e).ToList();
List<string> listString = (from e in result1
where !(from m in result2
select m.UserID).Contains(e.UserID)
select e.UserName).ToList();
ViewBag.ddlUserId = listString;
Am getting value inside listString .But got error while adding listString to viewbag.
Unable to cast object of type 'System.Collections.Generic.List`1[System.String]' to type 'System.Collections.Generic.IEnumerable`1[Main.Models.Admin.User]'.

First, could you update your question with the entire method so that we can see what might be going on with the ViewBag? Because your code should work just fine, assigning whatever value to the ViewBag is no problem normally:
ViewBag.property1 = 0;
ViewBag.property1 = "zero";
works just fine. ViewBag is dynamic. Now, you could get that error if you would later try to assing ViewBag.ddlUserId to something that actually is the wrong type.
I would like you to rewrite your statement as well, let me explain why. Assume for a moment that you have a lot ( > 100.000) of User records in your db.Users and we assume the same for Fi as well. In your code, result1 and result2 are now two lists, one containing >100.000 User objects and the other >100.000 Fi objects. Then these two lists are compared to each other to produce a list of strings. Now imagine the resource required for your web server to process this. Under the assumption that your actually using/accessing a separate SQL server to retrieve your data from, it would be a lot better and faster to let that server do the work, i.e. producing the list of UserID's.
For that you'd either use Kirill Bestemyanov's answer or the following:
var list = (from user in db.Users
where !db.Fi.Any(f => f.UserID == user.UserID)
select user.UserName).ToList()
This will produce just one query for the SQL server to execute:
SELECT
[Extent1].[UserName] AS [UserName]
FROM [dbo].[Users] AS [Extent1]
WHERE NOT EXISTS (SELECT
1 AS [C1]
FROM [dbo].[Fi] AS [Extent2]
WHERE [Extent2].[UserID] = [Extent1].[UserID]
)}
which in the end is what you want...
Just to clarify more:
var list = (from user in db.Users
where !db.Fi.Any(f => f.UserID == user.UserID)
select user.UserName).ToList()
can be written as the following lambda expression as well:
var list = db.Users.Where(user => !db.Fi.Any(f => f.UserID == user.UserID))
.Select(user => user.UserName).ToList()
which from the looks of it is slightly different from Kirill Bestemyanov's answer (which I slightly modified, just to make it look more similar):
var list = db.Users.Where(user => !db.Fi.Select(f => f.UserID)
.Contains(user.UserID))
.Select(user => user.UserName).ToList();
But, they will in fact produce the same SQL Statement, thus the same list.

I will rewrite it to linq extension methods:
List<string> listString = db.Users.Where(e=>!db.Fi.Select(m=>m.UserID)
.Contains(e.UserID))
.Select(e=>e.UserName).ToList();
try it, it should work.

Try this it is very simple.
var result=(from e in db.Users
select e.UserID).Except(from m in db.Fi
select m.UserID).ToList();

var res = db.tbl_Ware.where(a => a.tbl_Buy.Where(c => c.tbl_Ware.Title.Contains(mtrTxtWareTitle.Text)).Select(b => b.Ware_ID).Contains(a.ID));
This mean in T-SQL is:
SELECT * FROM tbl_Ware WHERE id IN (SELECT ware_ID, tbl_Buy WHErE tbl_Ware.title LIKE '% mtrTxtwareTitle.Text %')

getdata = (from obj in db.TblManageBranches
join objcountr in db.TblManageCountries on obj.Country equals objcountr.iCountryId.ToString() into objcount
from objcountry in objcount.DefaultIfEmpty()
where obj.IsActive == true
select new BranchDetails
{
iBranchId = obj.iBranchId,
vBranchName = obj.vBranchName,
Addressline1 = obj.Addressline1,
Adminemailid = obj.Adminemailid,
BranchType = obj.BranchType,
Country = objcountry.vCountryName,
CreatedBy = obj.CreatedBy,
CreatedDate = obj.CreatedDate,
iArea = obj.iArea,
iCity = obj.iCity,
Infoemailid = obj.Infoemailid,
Landlineno = obj.Landlineno,
Mobileno = obj.Mobileno,
iState = obj.iState,
Pincode = obj.Pincode,
Processemailid = obj.Processemailid,
objbranchbankdetails = (from objb in db.TblBranchesBankDetails.Where(x => x.IsActive == true && x.iBranchId == obj.iBranchId)
select new ManageBranchBankDetails
{
iBranchId = objb.iBranchId,
iAccountName = objb.iAccountName,
iAccountNo = objb.iAccountNo,
iBankName = objb.iBankName,
iAccountType = objb.iAccountType,
IFSCCode = objb.IFSCCode,
SWIFTCode = objb.SWIFTCode,
CreatedDate = objb.CreatedDate,
Id = objb.Id
}).FirstOrDefault(),
objbranchcontactperson = (from objc in db.tblbranchcontactpersons.Where(x => x.Isactive == true && x.branchid == obj.iBranchId)
select new ManageBranchContactPerson
{
branchid = objc.branchid,
createdate = objc.createdate,
Id = objc.Id,
iemailid = objc.iemailid,
ifirstname = objc.ifirstname,
ilandlineno = objc.ilandlineno,
ilastname = objc.ilastname,
imobileno = objc.imobileno,
title = objc.title,
updateddate=objc.updateddate,
}).ToList(),
}).OrderByDescending(x => x.iBranchId).ToList();

getdata = (from obj in db.TblManageBranches join objcountr in db.TblManageCountries on obj.Country equals objcountr.iCountryId.ToString() into objcount from objcountry in objcount.DefaultIfEmpty() where obj.IsActive == true
select new BranchDetails
{
iBranchId = obj.iBranchId,
vBranchName = obj.vBranchName,
objbranchbankdetails = (from objb in db.TblBranchesBankDetails.Where(x => x.IsActive == true && x.iBranchId == obj.iBranchId)
select new ManageBranchBankDetails
{
iBranchId = objb.iBranchId,
iAccountName = objb.iAccountName,
}).FirstOrDefault(),
objbranchcontactperson = (from objc in db.tblbranchcontactpersons.Where(x => x.Isactive == true && x.branchid == obj.iBranchId)
select new ManageBranchContactPerson
{
branchid = objc.branchid,
createdate = objc.createdate,
Id = objc.Id,
iemailid = objc.iemailid,
}).ToList(),
}).OrderByDescending(x => x.iBranchId).ToList();