I have a SQL Query
select Firma.Name as companyName,
Taetigkeit.Taetigkeit as skillName,
SUM(Zeit) as time
from Zeiterfassung
inner join Firma On ZEiterfassung.FirmenID = Firma.ID
inner join Taetigkeit on Zeiterfassung.TaetigkeitID = Taetigkeit.ID
group by Taetigkeit, Firma.Name
order by Firma.Name
And want to "translate" it to linq. Here is what I tried:
var query = db.Zeiterfassung
.Where(x => x.Firma.ID == x.FirmenID && x.TaetigkeitID == x.Taetigkeit.ID)
.GroupBy(x => x.Taetigkeit.Taetigkeit1)
.Select(x => new Evaluation() { skillName = x.Key, time = x.Sum(y => y.Zeit), //skillName = x.Sum(x => x.Zeit), })
.OrderBy(x => x.skillName);
I dont know who to solve this with joins and the group by because all the time when i do a groupBy i cant access the other members.
From data you provided, I think query should look like
from z in db.Zeiterfassung
join f in db.Firma on z.FirmenID equals f.ID
join t in db.Taetigkeit on z.TaetigkeitID equals t.ID
select new { f.Name, t.Taetigkeit, z.Zeit) into x
group x by new { x.Taetigkeit, f.Name } into g
select new {
CompanyName = g.Key.Name,
SkillName = g.Key.Taetigkeit,
Time = g.Sum(i => i.Zeit)
}
Or with navigation properties:
db.Zeiterfassung
.Select(z => new { z.Zeit, z.Taetigkeit.Taetigkeit1, z.Firma.Name })
.GroupBy(x => new { x.Taetigkeit1, x.Name })
.Select(g => new Evaluation {
companyName = g.Key.Name,
skillName = g.Key.Taetigkeit1,
time = g.Sum(y => y.Zeit)
});
Related
I'm translating a query and here's the original:
select top 5 t.usrID, u.FirstName, u.LastName, t.cnt as sCount
from (
select usrID, COUNT(rID) as cnt
from sessions as s where s.sDate > DATEADD(yy, -1, getdate())
group by usrID
) as t
inner join users as u on t.usrID = u.usrID
order by t.cnt desc
Here's what I have so far:
var topUser = (from p in _context.Sessions
where p.SDate > DateTime.Now.AddYears(-1)
join c in _context.Users on p.UsrId equals c.UsrId into j1
from j2 in j1.DefaultIfEmpty()
// group j2 by p.UsrId into grouped
select new
{
p.UsrId,
j2.FirstName,
j2.LastName,
cnt = p.RId
})
//.OrderBy(d => d.cnt)
//.GroupBy(o => o.UsrId)
.Take(5);
I'm having trouble figuring out how to include count() and group by clauses. When I include groupBy my other columns disappear. Thank you.
This is the answer to your answer - not to your original query. I would put it as comment, but without formatting it's hard to explain
Assuming User object has collection of Session your first statement can be drastically simplified:
var topUsers = _context.Sessions
.Where(s => s.SDate > DateTime.Now.AddYears(-1))
.Select(s => new
{
s.UsrId,
cnt = s.User.Sessions.Count(u => u.UsrId == s.UsrId)
})
.OrderByDescending(s => s.cnt)
.Take(5);
You can shape the results to get a ViewModel that also has FirstName and LastName. It all boils down to defining a model with one-to-many relationship
var topUser = (from p in _context.Sessions
where p.SDate > DateTime.Now.AddYears(-1)
join c in _context.Users on p.UsrId equals c.UsrId into j1
from j2 in j1.DefaultIfEmpty()
group j2 by p.UsrId into g
select new
{
UsrId = g.Key,
FirstName = g.Select(x => x.FirstName).FirstOrDefault(),
LastName = g.Select(x => x.LastName).FirstOrDefault(),
sCount = g.Count()
})
.OrderByDescending(d => d.sCount)
.Take(5);
Alright so it's not the most efficient but it works:
var topUsers = _context.Sessions
.Where(s => s.SDate > DateTime.Now.AddYears(-1))
.GroupBy(s => s.UsrId)
.Select(ws => new { ws.Key, cnt = ws.Count() })
.OrderByDescending(s => s.cnt)
.Take(5);
var topNamedUsers = topUsers.Join(_context.Users, ws => ws.Key, ud => ud.UsrId, (ws, ud) => new { ws.Key, ud.FirstName, ud.LastName, ws.cnt });
I've been puzzling over this problem all morning and can't figure out how to do it in C#.
My SQL query as follows:
select a.CourseID,
a.UserID
from audit a
inner join results r on a.UserID = r.UserID
inner join Course c on a.CourseID = c.CourseID
where c.CourseType = 9 and a.Guid = 'A123F123D123AS123123'
and a.Result = 'Passed' and r.Class = 'Maths'
group by a.CourseID, a.UserID
order by a.UserID
returns exactly what I want, but I can't seem to translate it into linq format. (the format being used here is what is required in my job at the moment so please advise on this format)
So far I have the following:
var audits = auditRepository.Get(a => a.Course.CourseType == 9 && a.GUID == this.Company.GUID && a.Result == "Passed", null, null,
a => a.Course, a => a.User)
.Join(resultsRepository.Get(r => r.GUID == this.Company.GUID && r.Class == class),
a => a.UserID,
r => r.UserID,
(a, r) => new Audit
{
User = a.User,
Course = a.Course,
Result = a.Result,
Timestamp = a.Timestamp,
AuditID = a.AuditID,
UserID = a.UserID
}
)
.OrderByDescending(o => o.Timestamp)
.GroupBy(u => new { u.User, u.Course })
.Select(grp => grp.ToList())
.ToList();
However this returns duplicates.
Any advice is appreciated, thanks
H
Instead of
.Select(grp => grp.ToList())
Select only the first element from each group to exclude duplicates:
.Select(grp => grp.First())
If you need a count also:
.Select(t => new{grp = t.First(),cnt = t.Count()} )
Fix:
.Select(t => new { grp = t.First(), cnt = t.Select(s => s.AuditID).Distinct().Count() })
How can I transform this SQL query to LINQ?
SELECT eg.Name Name, sum(bi.PlannedAmount) Amount
FROM BudgetItem bi, Expense e, ExpenseGroup eg
WHERE Discriminator = 'ExpenseItem' AND
bi.ExpenseId = e.Id AND
e.ExpenseGroupId = eg.id AND
bi.MonthlyBudgetId = 1
GROUP BY eg.Name
So far I've come up with this line:
var result = context
.ExpenseGroups
.GroupBy(eg => eg.Id, (s) => new { Name = s.Name, Amount = s.Expenses.SelectMany(e => e.Items).Sum(i => i.PlannedAmount) })
.ToList();
But I still cannot figure out what expression to use to add 'bi.MonthlyBudgetItem = 1'.
Does anybody have an Idea?
Edit #1:
I forgot to mention the relationships between the entities. Every ExpenseGroup has many Expenses, and every Expense has many BudgetItems.
So, ExpenseGroup => Expenses => BudgetItems
Edit #2:
I'm using Entity Framework and every ExpenseGroup has a Collection of Expense objects (every Expense has a ExpenseGroup object), as well as every Expense has a Collection of BudgetItem objects (every BudgetItem object has a Expense object).
I suppose something like this should do it:
var result = context
.ExpenseGroups
.Where(x => x.Discriminator == 'ExpenseItem' &&
x.bi.ExpenseId == e.Id &&
x.e.ExpenseGroupId == eg.id &&
x.bi.MonthlyBudgetId == 1)
.GroupBy(eg => eg.Id, (s) => new { Name = s.Name, Amount = s.Expenses.SelectMany(e => e.Items).Sum(i => i.PlannedAmount) })
.ToList();
Something similar to this...
var result = (from g in context.ExpenseGroups
where g.Expense.BudgetItem.MonthlyBudgetId == 1
select g)
.GroupBy(eg => eg.Id, (s) => new { Name = s.Name, Amount = s.Expenses.SelectMany(e => e.Items).Sum(i => i.PlannedAmount) })
.ToList();
or
var result = context.ExpenseGroups
.Where(g => g.Expense.BudgetItem.MonthlyBudgetId == 1)
.GroupBy(eg => eg.Id, (s) => new { Name = s.Name, Amount = s.Expenses.SelectMany(e => e.Items).Sum(i => i.PlannedAmount) })
.ToList();
You are actually doing an inner join in your SQL query, so do similarly in your linq query as well. This should work:-
var result = from bi in context.BudgetItem
join e in context.Expense
on bi.ExpenseId equals e.Id
where bi.MonthlyBudgetId == 1
join eg in ExpenseGroup
on e.ExpenseGroupId equals eg.id
group new { bi, eg } by eg.Name into g
select new
{
Name = g.Key,
Amount = g.Sum(x => x.bi.PlannedAmount)
};
I decided to try my hand at LINQ and so far its been a miserable failure. I need to convert the following SQL query to LINQ:
SELECT
MAX(A.NEXTPAYMENTDATE) as NextPaymentDate
, SUM(B.PurchasePrice) - SUM(A.Amount) AS BALANCE
, c.FirstName
, c.LastName
, b.[year]
, b.make
, b.model
FROM Payments A
JOIN Vehicles B ON A.VehicleId = B.Id
JOIN Customers C ON b.CustomerId = c.Id
GROUP BY VehicleId, c.FirstName, c.LastName, b.[year], b.make, b.model
HAVING SUM(B.PurchasePrice) - SUM(A.Amount) > 0
This is what I have so far. It seems to work to a certain extent, but I don't know how to progress from here.
var groupedpayments =
from payments in db.Payments
group payments by new { payments.VehicleId }
into paymentGroup
let maxDate = paymentGroup.Max(x => x.NextPaymentDate)
let paid = paymentGroup.Sum(x => x.Amount)
select
new { Payments = paymentGroup.Where(x => x.NextPaymentDate == maxDate)};
I think that is what you need.
var query =
Payments.Join(Vehicles, p => p.VehicleId, v => v.Id, (p, v) => new {p, v})
.Join(Customers, d => d.v.CustomerId, c => c.Id, (d, c) => new {d, c})
.GroupBy(r =>
new {
r.d.p.VehicleId,
r.d.v.year,
r.d.v.make,
r.d.v.model,
r.c.FirstName,
r.c.LastName
},
(g, data) =>
new {
FirstName = g.FirstName,
LastName = g.LastName,
Year = g.year,
Make = g.make,
Model = g.model,
NextPaymentDate = data.Max(dd => dd.d.p.NEXTPAYMENTDATE),
Balance = data.Sum(dd => dd.d.v.PurchasePrice)
- data.Sum(dd => dd.d.p.Amount)})
.Where(r => r.Balance > 0);
Having a T-SQL query:
select [ProductNumber] ,max([ProductRevNumber])
from Products
group by [ProductNumber]
Attempted LINQ query:
ProductsDBContext.Products.GroupBy(x => x.ProductRevNumber)
.Select(group => ProductNumber,
ProductRevNumber = group.Max(x => x.ProductRevNumber));
The lambda query doesn't work.
I think this is what you are after:
var latestProducts = ProductsDBContext.Products
.GroupBy(p => p.ProductNumber).Select(g => new
{
ProductNumber = g.Key,
MaxProductRevNumber = g.Max(p => p.ProductRevNumber))
});
from p in db.Products
group p by p.ProductNumber into g
select new
{
ProductNumber = g.Key,
ProductRevNumber = g.Max(p => p.ProductRevNumber)
};