I have a EF "Call" class which has a date, telephone number, caller name, and call cost.
My aim is to group the calls by the telephone number, and sum the total cost, and take the results of the 40 most expensive calls. I have all of this working, but I am having trouble with the projection, how do I get access to caller name?
var query =
(
from call in model.Calls
group call by call.TelephoneNumber into g
orderby g.Sum(gr => gr.ActualCost) descending
select new
{
TelephoneNumber = g.Key,
CallerName = ???
Cost = (g.Sum(gr => gr.ActualCost)),
TotalNumbers = g.Count(),
}
).Take(40);
You need group on the CallerName also:
var query =
(from call in model.Calls
group call by new { call.TelephoneNumber, call.CallerName } into g
orderby g.Sum(gr => gr.ActualCost) descending
select new
{
TelephoneNumber = g.Key.TelephoneNumber,
CallerName = g.Key.CallerName,
Cost = (g.Sum(gr => gr.ActualCost)),
TotalNumbers = g.Count(),
}).Take(40);
Related
I have an MVC ViewModel that I'd like to pass through to a Razor view. In the controller, I've created a database context and joined tables together using Linq. Once summed and grouped, I'm getting an error:
Error CS1061 'decimal' does not contain a definition for 'GroupBy' and no accessible extension method 'GroupBy' accepting a first argument of type 'decimal' could be found (are you missing a using directive or an assembly reference?
I've gone through almost every example on stack overflow and google and couldn't find an example that matched the structure of my query. Also, the MS examples are very trivial and are not of much use.
Here is the action in the controller:
public IHttpActionResult GetEmployeeReleasedAllocatedBonus(int eid)
{
var employeeReleasedAllocatedBonus =
(from br in _context.BonusReleases
join emp in _context.Employees
on new
{
br.EmployeeID,
empID = br.EmployeeID
} equals new
{
emp.EmployeeID,
empID = eid
}
join job in _context.Jobs on br.JobID equals job.JobID
join bonus in _context.Bonus
on new
{
br.JobID,
empID = br.EmployeeID
}
equals new
{
bonus.JobID,
empID = bonus.EmployeeID
}
select new EmployeeAllocatedReleasedBonusViewModel()
{
AllocatedToEmployee = br.Amount, AllocatedPercentage = bonus.Amount * 100
,
JobNumber = job.JobNumber, JobDescription = job.JobDescription
})
.ToList()
.Sum(s => s.AllocatedToEmployee)
.GroupBy(g => new {g.JobNumber, g.JobDescription, g.AllocatedPercentage});
return Ok(employeeReleasedAllocatedBonus);
}
It's worth mentioning that the AllocatedPercentage datatype is a decimal. However, I've tried changing it to string but the error message stays.
Also tried using the group functionality right before .ToList() but that didn't work either.
After ToList() you have a List<EmployeeAllocatedReleasedBonusViewModel>.
In Sum(s => s.AllocatedToEmployee), every s is one EmployeeAllocatedReleasedBonusViewModel. Apparently a EmployeeAllocatedReleasedBonusViewModel has a property AllocatedToEmployee which is probably of type decimal. This can be summed into one decimal.
The result of the Sum (a decimal) is the input of your GroupBy. Does type decimal have a method GroupBy? Of course it doesn't!
Alas you forgot to tell us your requirements. It is difficult to extract them from code that doesn't do what you want.
It seems to me that you have two one-to-many relations:
Employees have zero or more BonusReleases. Every BonusRelease belongs to exactly one Employee using foreign key
Jobs have zero or more BonusReleases. Every BonusRelease belongs to exactly one Job.
Now what do you want: do you want all JobNumbers and JobDescriptions of all Jobs with the total of their AllocatedPercentage? I'm not sure what the Employees do within this query.
Whenever you want items with their sub-items, like Schools with their Students, Customers with their Orders, Orders with their OrderLines, use GroupJoin. If you want it the other way round: Student with the School that he attends, Order with the Customer who placed the Order, use Join.
var result = dbContext.Jobs.GroupJoin(dbContext.BonusReleases,
job => job.Id, // from every Job take the primary key
bonusRelease => bonusReleas.JobId, // from every BonusRelease take the foreign key
// parameter ResultSelector: take every Job with all its BonusReleases to make a new:
(job, bonusReleasesOfThisJob) => new
{
JobNumber = job.JobNumber,
JobDescription = job.JobDescription
// do you want the total of all allocated percentages?
TotalAllocatedPercentages = bonusReleasesOfThisJob
.Select(bonus => bonus.Amount)
.Sum(),
// do something to make it a percentage
// or do you want a sequence of allocated percentages?
TotalAllocatedPercentages = bonusReleasesOfThisJob
.Select(bonus => bonus.Amount)
.ToList(),
});
Or do you want the JobNumber / JobDescription / Total allocated bonus per Employee?
var result = dbContext.Employees.GroupJoin(dbContext.BonusReleases,
employee => employee.Id, // from every Employee take the primary key
bonus => bonus.EmployeeId, // from every BonusRelease take the foreign key
(employee, bonusesOfThisEmployee) => new
{
// Employee properties:
EmployeeId = employee.Id,
EmpoyeeName = employee.Name,
// for the jobs: Join the bonusesOfThisEmployee with the Jobs:
Jobs = dbContext.Jobs.GroupJoin(bonusOfThisEmployee,
job => job.Id,
bonusOfThisEmployee => bonusOfThisEmployee.JobId,
(job, bonusesOfThisJob) => new
{
Number = job.Id,
Description = job.Description,
TotalBonus = bonusOfThisJob.Select(bonus => bonus.Amount).Sum(),
}),
});
Harald's comment was key - after ToList(), I had a list of . Therefore I took a step back and said what if I put the results into an anonymous object first. Then do the group by and then the sum, putting the final result into the view model. It worked. Here is the answer.
var employeeReleasedAllocatedBonus =
(from br in _context.BonusReleases
join emp in _context.Employees
on new
{
br.EmployeeID,
empID = br.EmployeeID
} equals new
{
emp.EmployeeID,
empID = eid
}
join job in _context.Jobs on br.JobID equals job.JobID
join bonus in _context.Bonus
on new
{
br.JobID,
empID = br.EmployeeID
}
equals new
{
bonus.JobID,
empID = bonus.EmployeeID
}
select new
{
AllocatedToEmployee = br.Amount
,AllocatedPercentage = bonus.Amount * 100
,JobNumber = job.JobNumber
,JobDescription = job.JobDescription
})
.GroupBy(g => new {g.JobNumber, g.JobDescription, g.AllocatedPercentage})
.Select(t => new EmployeeAllocatedReleasedBonusViewModel
{
JobNumber = t.Key.JobNumber,
JobDescription = t.Key.JobDescription,
AllocatedPercentage = t.Key.AllocatedPercentage,
AllocatedToEmployee = t.Sum(ae => ae.AllocatedToEmployee)
});
I'm trying to display cities names where a count is greater than 1. I can do it easy in SQL and am close in LINQ but can't figure out how to use group and also get a count and display a name
var query = (from c in Consumer
group c
by new { c.City, size = c.City.Count() }
into results
select new { Name = results.Key.City })
.Where(a => size > 0);
The size part doesn't work
try this query:
var list= Consumer.GroupBy(s=>s.City)
.Select(s=>new {
City = s.Key,
size = s.Count(),
})
.Where(s=>s.size>0).ToList();
I have a table with a date field and time field.I want to retrieve a result set grouped by the month and the number of records that appear within that month. How can this be done in LINQ?
Something like this.
Data.
10/10/2011 00:00:10:000
10/11/2011 00:00:20:000
11/01/2011 00:00:10:000
11/10/2011 00:00:40:000
I want to retrieve
10/1/2011 00:00:30:000
11/1/2011 00:00:50:000
Thank`s for help.
i am try something like this.
var monthely =
from u in sqlDataContract.TimeTrickTables
group u by u.EntryDate.Value.Month into g
select new
{
EntryDate = g.Key,
ETime = g.Aggregate(TimeSpan.Zero, (subtotal, t) => subtotal.Add((TimeSpan)t.ETime))
};
but it throw this Exception The query operator 'Aggregate' is not supported
from u in TimeTrickTables
group u by u.EntryDate.Value.Month into g
select new
{
Month = g.Key,
Count = g.Count(), //Nr. of records
Time = new TimeSpan(g.Sum(x => x.ETime.Ticks)) //Total time
}
I have divAssignments that has potential multiple rows by rNI, an official id, according to a compound key of Indictment and booking numbers.
rNI Booking Indictment
12345 954445 10 12345
12345 954445 10 12346
12345 954445 10 12347
So ID has a count of 3 for a single booking number for this rni.
I get lost attempting to generate a count and a group by booking Number:
var moreThen = from dA in divAssignments
select new { dA.rNI, IndictmentCount = dA.indictmentNumber.Count() };
Most of the examples are dealing with static int[] and don't seem to work in my case.
How do I get a group and then a count? If I could put in a having that would be fantastic.
from a t-sql POV I'd use this:
Select rni, bookingNumber, count(*) IndictmentCount
from divAssignments
group by rni, bookingNumber
having count(*) > 0
TIA
How about something like this:
var query = from item in divAssignments
group item by item.rNI into grouping
select new
{
Id = grouping.Key,
Count = grouping.Count()
}
If you're interested in grouping by both the rNI and the booking number, I would change it to this:
var query = from item in divAssignements
group item by new { item.rNI, a.Booking } into grouping
select new
{
Id = grouping.Key,
Count = grouping.Count
};
OR
var query = from item in divAssignments
group item by item into grouping
select new
{
Id = grouping.Key,
Count = grouping.Count()
}
and implement IEquatable on the divAssignment object to support equality comparison. The other option if you'd like is to write an IEqualityComparer instance to do the composite key comparison. Your query could then look like:
var query =
divAssignments
.GroupBy(i => i, new MyCustomEqualityComparer())
.Select(i => new { Key = i.Key, Count = i.Count());
var query =
from dA in divAssignments
group dA by new { dA.rNI, dA.bookingNumber };
foreach(var grp in query)
{
Console.WriteLine("rNI={0}, bookingNumber={1} => Count={2}", grp.Key.rNI, grp.Key.bookingNumber, grp.Count());
}
If you use a Grouping operator in Linq you will get what you need. The code:
var count = from a in divAssignments
group a by new { a.rNI, a.Booking } into b
select b;
will return a collection of IGrouping objects. This will give you the Key (in my example this will be an anonymous type with an rNI and a Booking property) and a collection of the divAssignments that match the key.
Using Method syntax (much easier to read in my opinion):
First group the records, then select a new result for each group that contains the count.
var groups = divAssignments.GroupBy(d => new { d.rNI, d.Booking });
groups.Select(g=> new { g.Key.rNI, g.Key.Booking, IndictmentCount = g.Count() });
I have the following LINQ conditional where clause query that produces a result of weights:
From this, I'd like to take the result set and join on another table, tblPurchases
var result = weights.Join(getsuppliersproducts.tblPurchases,
w => new { w.MemberId, w.MemberName, w.LocationId, w.UnitId },
p => new { p.MemberId, p.MemberName, p.LocationId, p.UnitId },
(w, p) => p);
In this second table, I have two columns I would like to perform an aggreagte function on, a sum on PurchaseQuantity and a count of UnitID.
So in its raw format, tblPurchases would look like so:
MemberID LocationID UnitId SupplierID SupplierStatus Purchases
1 1 ab Sup1 Live 10
1 1 abc Sup1 Live 10
1 1 abcd Sup2 Dead 50
From my results data set, I would like the output to look like so:
MemberID LocationID SupplierID SupplierStatus UnitIdCount Total Purchases
1 1 Sup1 Live 2 50
Also, with these amendments, can I still return this to a List?
How do I implement this using LINQ? I have tried, and failed miserably.
(To those who have seen my previous posts, I'm trying to cover all angles so I can fully understand the concept of what is going on in both SQL and LINQ)
That query will return an IEnumerable where each of the Purchases matches the MemberId, MemberName, LocationId and UnitId in the original Weights query. You can only easily do one aggregate at a time, so
var result = weights.Join(getsuppliersproducts.tblPurchases,
w => new { w.MemberId, w.MemberName, w.LocationId, w.UnitId },
p => new { p.MemberId, p.MemberName, p.LocationId, p.UnitId },
(w, p) => p).ToList();
Int32 count = result.Count();
Double quantity = result.Sum(p => p.PurchaseQuantity);
Is that what you're trying to do?
EDIT, after your reply of I would like to reutrn a list of tblPurchases with two new columns, the sum of Purchase Quantity and count of unit ID.
This gives a flat output:
var query = Weights.GroupJoin(
Purchases,
w => new {w.MemberId, w.LocationId},
p => new {p.MemberId, p.LocationId},
(w,p) => new {w.MemberId, w.LocationId, Count = p.Count(), Sum = p.Sum(x => x.Purchases)} );
Note that at the point we do the (w, p) => new {} that w is a single Weight and p is a list of Purchases matching that weight, so you can still keep all of teh (hierarchical) data:
var query = Weights.GroupJoin(
Purchases,
w => new {w.MemberId, w.LocationId},
p => new {p.MemberId, p.LocationId},
(w,p) => new {w.MemberId, w.LocationId, Count = p.Count(), Sum = p.Sum(x => x.Purchases), Purchases = p} );