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Problems recreating LINQ query from SQL script

I'm struggling in 'translating' a SQL query to a LINQ query. My SQL query looks like this:
SELECT S.SummonerName, LE.LeaguePoints, LS.DateTime, SUM(LE.LeaguePoints)
FROM LadderEntries LE
JOIN Sumonners S on LE.SummonerId = S.Id
JOIN LadderSnapshots LS on LE.LadderSnapshotId = LS.Id
WHERE LS.Region = 'euw1'
AND DateTime = '2019-06-14 00:00:00'
OR DateTime = '2019-06-13 00:00:00'
and LS.Region = 'euw1'
GROUP BY S.SummonerName
This query gives me the desired result. However, so far I got the following LINQ query:
from LE in _database.LadderEntries
join S in _database.Sumonners on LE.SummonerId equals S.Id
join LS in _database.LadderSnapshots on LE.LadderSnapshot.Id equals LS.Id
where LS.Region == param.Region && (LS.DateTime == param.Date || LS.DateTime == param.Date.AddDays(-1))
group new {LE, S, LS} by S.SummonerName
into C
select new GetLadderEntryDifferencesEntry
{
LpDifference = C.Select(a => a.LE.LeaguePoints).Sum(),
SummonerName = C.Select(a => a.S.SummonerName).FirstOrDefault()
};
But this gives me the error InvalidOperationException: Error generated for warning 'Microsoft.EntityFrameworkCore.Query.QueryClientEvaluationWarning: The LINQ expression 'GroupBy([S].SummonerName, new <>f__AnonymousType5'3(LE = [LE], S = [S], LS = [LS]))' could not be translated and will be evaluated locally.'. on execution.
I'm wondering what I'm doing wrong.
Note: I'm using sqllite and ef core if that makes a difference.

I believe the issue will be with:
&& (LS.DateTime == param.Date || LS.DateTime == param.Date.AddDays(-1))
try this:
var firstDate = param.Date;
var secondDate = param.Date.AddDays(-1);
then
&& (LS.DateTime == firstDate || LS.DateTime == secondDate)
possibly it may be taking exception to:
SummonerName = C.Select(a => a.S.SummonerName).FirstOrDefault()
or how the grouping is arranged.
Are these entities set up with references and can the expression be simplified?
var ladderEntryDifferences = _database.LadderSnapshots
.Where(x =>x.Region = param.Region
&& (x => x.DateTime == firstDate || x.DateTime == secondDate)
.GroupBy(x => x.LadderEntry.Summoner.SummonerName)
.Select( g => new GetLadderEntryDifferencesEntry
{
LpDifference = g.Sum(x => x.LeagueEntry.LeaguePoints),
SummonerName = g.Key // This will be the SummonerName
}).ToList();
The above is a guess about the structure, and pulling the group by from memory, but it might give you some ideas to try. If your context does not expose LadderSnapshots at a top level, you should be able to compose it from the LadderEntry level as well...

Ok here is what i got, first
LS.Region = 'euw1'
AND DateTime = '2019-06-14 00:00:00'
OR DateTime = '2019-06-13 00:00:00'
and LS.Region = 'euw1'
is not the same as the below linq, where the parameters is missing in the sql.
&& (LS.DateTime == param.Date || LS.DateTime == param.Date.AddDays(-1))
Now about the group by you could try to do it like this instead
from LE in _database.LadderEntries
join S in _database.Sumonners on LE.SummonerId equals S.Id
join LS in _database.LadderSnapshots on LE.LadderSnapshot.Id equals LS.Id
where LS.Region == param.Region && (LS.DateTime == param.Date || LS.DateTime == param.Date.AddDays(-1))
group LE by new {LE.SummonerName, S.SummonerName, LS.SummonerName}
into C
select new GetLadderEntryDifferencesEntry
{
LpDifference = C.Select(a => a.LE.LeaguePoints).Sum(),
SummonerName = C.Select(a => a.S.SummonerName).FirstOrDefault()
};

How to convert nested sql statement to linq to entities?

I'm trying to create a basic room availability statement to use with linq to entity framework. I have two tables: 'Room' including columns RoomID/RoomSize and 'Booking' including BookingID/RoomID/StartDate/Enddate.
I have got a working sql statement:
SELECT RoomID, RoomSize from Room
where RoomID NOT IN (SELECT RoomID from booking
where ('08/01/2015' >= [start] AND '08/01/2015' <= [end]) OR ('08/20/2015' >= [start] AND '08/20/2015' <= [end]))
I have got this far with the linq to entity statement:
var rooms = (from r in db.Rooms
where !(((from b in db.Bookings
where (startDate >= b.StartDate && endDate <= b.EndDate) || (endDate >= b.StartDate && endDate <= b.EndDate)).Contains(r.RoomID))
select new AvailableRoom
{
ID = r.RoomID,
Size = r.RoomSize
});
I get an error at the last bracket before .Contains(r.RoomID) saying I should have a select statement but I just can't seem to get it working.
Any suggestions would be welcome.
If you reckon using lambdas would be better/easier please feel free to suggest and example. I'm just not too familiar with them myself.. yet.
Thank you.

You can use LINQ !...Any() for the SQL NOT IN(), like so :
var rooms = (from r in db.Rooms
where !db.Bookings
.Where(b => (startDate >= b.StartDate && endDate <= b.EndDate)
||
(endDate >= b.StartDate && endDate <= b.EndDate)
)
.Any(b => b.RoomID == r.RoomID)
select new AvailableRoom
{
ID = r.RoomID,
Size = r.RoomSize
});

LINQ with multiple columns and operations

i'm trying to do this on LINQ:
select p.ProductID, p.ArticleCode, SUM((case h.OperationType when 0 then 1 else -1 end) * h.[Count])
from Products p
inner join StockItems s on p.ArticleCode = s.ArticleCode
inner join StockHistorical h on s.ArticleID = h.ArticleID
where h.[Date] < '23/08/2013 11:30:00'
group by p.ProductID, p.ArticleCode
I have this:
var products = (from p in e.Products
join s in e.StockItems on p.ArticleCode equals s.ArticleCode
join h in e.StockHistoricals on s.ArticleID equals h.ArticleID
where h.Date < DateTime.Parse("23/08/2013 11:30:00")
group p by p.ProductID into StockResult
select new { });
Anyone know how can i do the
SUM((case h.OperationType when 0 then 1 else -1 end) * h.[Count])
with LINQ?
Thanks!
I forgot to say that the problem is the "group by", because i can't access the OperationType property in the StockResult group.
Solved! The key is the:
let combined = new
{
Product = p,
HistoryCount = (h.OperationType == 0 ? 1 : -1) * h.Count
}

...
let combined = new
{
Product = p,
HistoryCount = (h.OperationType == 0 ? 1 : -1) * h.Count
}
group combined by combined.Product.ProductID into StockResult
select new
{
ProductID = StockResult.Key,
Total = StockResult.Sum(x => x.HistoryCount)
}

It's not a direct translation, but I'd go with:
(h.Count(his => his.OperationType != 0)
- h.Count(his => his.OperationType == 0))
* h.Count()
It should be functionally equivalent, and seems to better represent what you're trying to do.

You are trying to do something like this?
I am not sure this is going to work.
select new
{
S=Sum(((h.OperationType)!=0?-1:1)*h.Count)
}

SQL to LINQ Converter

I have a SQL and having a hard time to convert it to LINQ. Are there any other tools that can convert SQL to LINQ? I heard Linqer and tried it but it doesn't allow you to query on the Junction/Join Table of a Many-to-Many relationship tables. In any case here's the SQL that I need to convert to LINQ or even lambda.
SELECT A.*
FROM
( SELECT TOP 10 T2.ID,
T2.Name,
SUM(T1.Column1 + T1.Column2 + T1.Column3) AS Total
FROM POS.dbo.Table1 T1
INNER JOIN POS.dbo.Table2 T2 on T2.ID = T1.ID
WHERE T2.ID IN
(
SELECT ID FROM POS.dbo.Table3 WHERE [Id] = 1
)
AND [Date] BETWEEN '2011-11-09 00:00:00' AND '2011-11-09 23:59:59'
GROUP BY T2.ID, T2.Name
ORDER BY Total DESC
) A
ORDER BY Name ASC
Here is my first attempt:
var query = db.Table1
.Include(e => e.Table2)
.Where(x => x.Date >= '2011-11-09 00:00:00'
&& x.DateCreated <= '2011-11-09 23:59:59')
.Where(y => y.Table2.Table3.Any(u => u.Id == 1))
.Take(10);

One of the things I like most about Linq is that it will combine queries together, so I break a complicated query into subqueries and let Linq recombine them all.
Using that basis, does something like this work.
DateTime startDate = new DateTime(2011,11,9);
DateTime endDate = new DateTime(2011,11,9,23,59,59);
var table3Ids = (from r in Pos.dbo.Table3 where id = 1 select r.id) ;
var query1 =
(
from t1 in Pos.dbo.Table1
where t1.Table2.Id == 1 && t1.Date >= startDate && t1.Date <= endDate
where table3Ids.Contains(t1.Table2.Id)
group t1 by new { t1.Table2.Id , t1.Table2.Name} into results
select new
{
results.Key.Id ,
results.Key.Name ,
Total = results.Sum(r=> (r.Column1 + r.Column2 + r.Column3))
}
);
var query2 = (from r in query1 orderby r.Total descending select r).Take(10);
var query3 = (from r in query2 orderby r.Name select r);
var list = query3.ToList();

Here's my shot - it's a bit hard without knowing the actual data structure or the expected results:
var query = db.Table1
.Join(db.Table2, table1 => table1.Id, table2 => table2.Id, (t1, t2) => new {
Id = t2.Id,
Name = t2.Name,
Total = (t1.Column1 + t1.Column2 + t1.Column3),
Date = t1.Date //you didn't use a table alias for this field, so I'm not sure which table it comes from
})
.Where(x => x.Date >= new DateTime(2011, 11, 9)
&& x.DateCreated <= new DateTime(2011, 11, 9, 23, 59, 59))
.Join(db.Table3, x => x.Id, table3 => table3.Id, (x, t3) => new {
Id = x.Id,
Name = x.Name,
x.Total
})
.Where(x => x.Id == 1)
.OrderByDescending(x => x.Total)
.ThenBy(x => x.Name)
.Take(10)
.ToList()
Because that might be the craziest Linq statement I've ever written, don't assume it'll work the first time, but it's at least a good starting point.

How to merge 5 different type of linq queries into one based on a column

I am really confused on a report I need. As of today, most of my reports were simple, so I was able to do them myself easily. But being a newbie in sql/dlinq, I cannot find my way through the following:
var closingStock =
(from p in session.Query<Product>()
select new
{
p.Id,
p.Name,
p.Batch,
p.Rate,
ClosingStock = p.Quantity - p.AllocatedQuantity,
p.DivisionId
}).ToList();
var distributedQuantityAfterPeriod =
(from i in session.Query<OutwardInvoiceItem>()
where i.ParentInvoice.Date > ToDate
select new
{
Id = i.Product.Id,
DistributedAfter = i.Quantity
}).ToList();
var distributedQuantityInPeriod =
(from i in session.Query<OutwardInvoiceItem>()
where i.ParentInvoice.Date >= FromDate && i.ParentInvoice.Date <= ToDate
select new
{
Id = i.Product.Id,
Distributed = i.Quantity
}).ToList();
var receivedQuantityAfterPeriod =
(from i in session.Query<InwardInvoiceItem>()
where i.ParentInvoice.Date > ToDate
select new
{
Id = i.Product.Id,
ReceivedAfter = i.Quantity
}).ToList();
var receivedQuantityInPeriod =
(from i in session.Query<InwardInvoiceItem>()
where i.ParentInvoice.Date >= FromDate && i.ParentInvoice.Date <= ToDate
select new
{
Id = i.Product.Id,
Received = i.Quantity
}).ToList();
As you can see, I am trying to build a inventory movement report for a specific date. I have the following problems:
1. How can I reduce the five queries? Is it possible?
2. How can I merge the data provided by these queries into one table which is grouped on the product id and summed on the quantity related columns? As of now, I am using for loops which are really slow.
What I am using:
C# 4, nHibernate, Sqlite
Any help will be very highly appreciated.
Regards,
Yogesh.

to reduce roundtrips use .Future() instead of .List()
let all queries return
group i by i.Id into g
select new
{
Id = g.Key,
Quantity = g.Sum(x => x.Quantity)
}).Future();
and do
var alltogether = groupedDistributedQuantityAfterPeriod
.Concat(groupedDistributedQuantityInPeriod)
.Concate(...);
from g in alltogether
group g by g.key into all
select new
{
Id = all.Key,
Quantity = all.Sum(x => x.Quantity)
};
Update:
you can reduce the number of queries with
from i in session.Query<OutwardInvoiceItem>()
where (i.ParentInvoice.Date > ToDate) || (i.ParentInvoice.Date >= FromDate && i.ParentInvoice.Date <= ToDate)
select ...
from i in session.Query<InwardInvoiceItem>()
where (i.ParentInvoice.Date > ToDate) || (i.ParentInvoice.Date >= FromDate && i.ParentInvoice.Date <= ToDate)
select ...