Get Count from entity framework - linq

Quite new to EF, basically i want to convert this SQL query:
SELECT
PSKU.ProductSKUID,
PSKU.ProductSKUName,
W.WarehouseID,
W.WarehouseName,
SA.SystemAreaName,
COUNT(SLI.ProductSKUID) AS QTY
FROM dbo.StockLineItem AS SLI INNER JOIN
dbo.ProductSKU AS PSKU ON PSKU.ProductSKUID = SLI.ProductSKUID INNER JOIN
dbo.Warehouse AS W ON W.WarehouseID = SLI.WarehouseID INNER JOIN
dbo.SystemArea AS SA ON SA.SystemAreaID = SLI.SystemAreaID
WHERE (SA.SystemAreaID = 1)
AND W.WarehouseID = #WarehouseID
GROUP BY PSKU.ProductSKUID, PSKU.ProductSKUName, W.WarehouseName, SA.SystemAreaName, W.WarehouseID
To an effective EF statement. This is what i Have so far, my Model class and the method:
[Serializable]
public class StockReturnMethod
{
public int ProductSKUID { get; set; }
public int WarehouseID { get; set; }
public int LotID { get; set; }
public string LotName { get; set; }
public int AreaID { get; set; }
public string AreaName { get; set; }
public int BinID { get; set; }
public string BinName { get; set; }
}
public class DALStockMovement
{
scmEntitiesPrimaryCon entities = new scmEntitiesPrimaryCon();
public List<AvailibleStock> AvailibleStockQty(int warehouseID)
{
var rows = (from PLA in entities.ProductLocationAssignments
from W in entities.Warehouses
from SLI in entities.StockLineItems
from SA in entities.SystemAreas
from PSKU in entities.ProductSKUs
where W.WarehouseID == warehouseID
select new AvailibleStock() { WarehouseID = W.WarehouseID, ProductSKUID = PSKU.ProductSKUID, ProductSKUName = PSKU.ProductSKUName, WarehouseName = W.WarehouseName, Status = SA.SystemAreaName, QtyUnassigned = SLI.ProductSKUID }).ToList();
return rows;
}
Any Advice to get this to an Effective EF Statement would be appreciated

I actually used this tool called Linqer, since I had the SQL
I just popped it into that tool and it generated the Linq for me.
Here is what came out:
var SKUStock = (from sli in entities.StockLineItems
where
sli.SystemArea.SystemAreaID == 1 &&
sli.WarehouseID == warehouseID
group new { sli.ProductSKU, sli.Warehouse, sli.SystemArea, sli } by new
{
ProductSKUID = (System.Int32?)sli.ProductSKU.ProductSKUID,
sli.ProductSKU.ProductSKUName,
sli.Warehouse.WarehouseName,
sli.SystemArea.SystemAreaName,
WarehouseID = (System.Int32?)sli.Warehouse.WarehouseID
} into g
select new AvailibleStock()
{
ProductSKUID = (int)(System.Int32?)g.Key.ProductSKUID,
ProductSKUName = g.Key.ProductSKUName,
WarehouseID = (int)(System.Int32?)g.Key.WarehouseID,
WarehouseName = g.Key.WarehouseName,
Status = g.Key.SystemAreaName,
QtyUnassigned = (int)(Int64?)g.Count(p => p.sli.ProductSKUID != null)
}).ToList();
return SKUStock;
It returns exactly what i need :).

Related

how to add the number of items at the end of the linq query

i have the following LINQ
public IEnumerable<TurbineStatus> turStatus()
{
var result = (from s in _db.masterData
group s by s.current_turbine_status into g
select new TurbineStatus
{
status = g.Key,
numberOfTurbines = g.Count()
}
).ToList().OrderByDescending(s => s.status);
return result;
}
my class:
public class TurbineStatus
{
public string status { get; set; }
public int numberOfTurbines { get; set; }
public int allTurbines { get; set; }
}
i gives me the number of turbines according to the status,for example, 5turbines STOP,6 turbines RUN,10 turbines Link Down and so on,i also need to have sum of all these statuses,in my TurbinesStatus class i have a field which is int and named it allTurbines,how can i achieve it?
It's probably better for performance reasons to let the DB handle sorting and then once the result is materialized, you can extract the sum of the turbines count:
var result =
(
from s in _db.masterData
group s by s.current_turbine_status into g
select new TurbineStatus
{
status = g.Key,
numberOfTurbines = g.Count()
} into statusGroup
orderby statusGroup.status descending
select statusGroup
).ToList();
int totalTurbines = groups.Sum(statusGroup => statusGroup.numberOfTurbines);
To return both as a TurbinesStatus instance:
public class TurbinesStatus
{
public IReadOnlyList<TurbineStatus> TurbineStatuses { get; }
public int TotalCount { get; }
public TurbinesStatus(IReadOnlyList<TurbineStatus> turbineStatuses)
{
TurbineStatuses = turbineStatuses;
TotalCount = turbineStatuses.Sum(ts => ts.numberOfTurbines);
}
}
and then
public TurbinesStatus turStatus()
{
var statuses =
(
from s in _db.masterData
group s by s.current_turbine_status into g
select new TurbineStatus
{
status = g.Key,
numberOfTurbines = g.Count()
} into statusGroup
orderby statusGroup.status descending
).ToList();
return new TurbinesStatus(statuses);
}

left join two tables in same DataContext LinQ in c#

I have two table in the same DataContext as follows.
Table PersonnelInfo
{
personnelId,
personnelName ,
description,
deathMonthYear,
updatedBy,
updatedAt
}
Table PersonnelInfoOther
{
personnelId,
personnelName ,
updatedBy,
updatedAt
}
I define a class as follows:
public class PersonnelInfoAll
{
public short personnelId{get;set;}
public string personnelName { get; set; }
public string personnelNameOtherLan { get; set; }
public string description { get; set; }
public string deathMonthYear { get; set; }
public int updatedBy { get; set; }
public DateTime updatedAt { get; set; }
}
I need to left join first table with the second one and retrieve all the data as PersonnelInfoAll format:
public List<PersonnelInfoAllLan> GetPersonnelInfosAll()
{
var context = new BookDataClassesDataContext { ObjectTrackingEnabled = false };
var personnelInfo = from u in context.PersonnelInfos
join b in context.PersonnelInfoOtherLans
on u.personnelId equals b.personnelId
select new PersonnelInfoAllLan
{
personnelId = u.personnelId,
personnelName = u.personnelName,
personnelNameOtherLan = b.personnelName,
description = u.description,
deathMonthYear = u.deathMonthYear,
updatedBy = u.updatedBy,
updatedAt = u.updatedAt
};
return personnelInfo.ToList();
}
This gives me only one row which matches with both. But I need all the records from the first table. Is there any one to help.
Use group join:
var personnelInfo = from p in context.PersonnelInfos
join l in context.PersonnelInfoOtherLans
on p.personnelId equals l.personnelId into g
from l in g.DefaultIfEmpty()
select new PersonnelInfoAllLan
{
personnelId = p.personnelId,
personnelName = p.personnelName,
personnelNameOtherLan = (l == null ? null : l.personnelName),
description = p.description,
deathMonthYear = p.deathMonthYear,
updatedBy = p.updatedBy,
updatedAt = p.updatedAt
};
If there no match in lans for some person, then DefaultIfEmpty() will return null from joined group. That's why you need to check l for null.

Dynamic LINQ: Comparing Nested Data With Parent Property

I've a class with following structure:
public class BestWayContext
{
public Preference Preference { get; set; }
public DateTime DueDate { get; set; }
public List<ServiceRate> ServiceRate { get; set; }
}
public class ServiceRate
{
public int Id { get; set; }
public string Carrier { get; set; }
public string Service { get; set; }
public decimal Rate { get; set; }
public DateTime DeliveryDate { get; set; }
}
and I've dynamic linq expression string
"Preference != null && ServiceRate.Any(Carrier == Preference.Carrier)"
and I want to convert above string in Dynamic LINQ as follows:
var expression = System.Linq.Dynamic.DynamicExpression.ParseLambda<BestWayContext, bool>(condition, null).Compile();
But it showing following error:
Please correct me what am I doing wrong?
It looks like you wanted to do something like this:
var bwc = new BestWayContext
{
Preference = new Preference { Carrier = "test" },
DueDate = DateTime.Now,
ServiceRate = new List<ServiceRate>
{
new ServiceRate
{
Carrier = "test",
DeliveryDate = DateTime.Now,
Id = 2,
Rate = 100,
Service = "testService"
}
}
};
string condition = "Preference != null && ServiceRate.Any(Carrier == #0)";
var expression = System.Linq.Dynamic.DynamicExpression.ParseLambda<BestWayContext, bool>(condition, bwc.Preference.Carrier).Compile();
bool res = expression(bwc); // true
bwc.ServiceRate.First().Carrier = "test1"; // just for testing this -> there is only one so I've used first
res = expression(bwc); // false
You want to use Preference which belong to BestWayContext but you didn't tell the compiler about that. If i write your expression on Linq i will do as follows:
[List of BestWayContext].Where(f => f.Preference != null && f.ServiceRate.Where(g => g.Carrier == f.Preference.Carrier)
);
As you see i specified to use Preference of BestWayContext.

How can I use be generic to result of linq query?

Be first, my English is not very good. So I am sorry about that. :)
My question as the title. I have two tables on my database:
Siniflar (SinifId, SinifAdi, Kapasite, OgretmenId)
Ogretmenler (OgretmenId, Ad, Soyad, Brans)
Query:
var siniflar = (from s in db.Siniflar
join o in db.Ogretmenler
on s.OgretmenId equals o.OgretmenId
select new { s.SinifId, s.SinifAdi, s.Kapasite, o.Ad }).ToList();
I want to use the result of the query as a generic, like this:
public List<Siniflar> SiniflariListele()
{
var siniflar = (from s in db.Siniflar
join o in db.Ogretmenler
on s.OgretmenId equals o.OgretmenId
select new { s.SinifId, s.SinifAdi, s.Kapasite, o.Ad }).ToList();
return siniflar;
}
But I get an error. Because the result is anonymous types.
Error: Cannot implicitly convert type System.Collections.Generic.List<AnonymousType#1> to System.Collections.Generic.List<Entity.Siniflar>
How Can I use be generic result. What Can I do for that?
I changed question:
Class:
public class RSiniflar
{
public int SinifId { get; set; }
public string SinifAdi { get; set; }
public int Kapasite { get; set; }
public string OgretmenAdiSoyadi { get; set; }
}
Metod:
public List<RSiniflar> SiniflariListele()
{
List<RSiniflar> siniflar = (from s in db.Siniflar
join o in db.Ogretmenler
on s.OgretmenId equals o.OgretmenId
select new RSiniflar
{
SinifId = s.SinifId,
SinifAdi = s.SinifAdi,
Kapasite = s.Kapasite,
OgretmenAdiSoyadi = o.Ad + ' ' + o.Soyad
}).ToList();
return siniflar;
}
But now error to query: Unable to create a constant value of type 'System.Object'. Only primitive types or enumeration types are supported in this context.
I think, there are a problem on my query... I get an error same when query to var type...
You can return typed list, but you can't return a list of anonymous type. So you need to create a class which will handle your results:
public class A
{
public int SinifId { get; set; }
public int SiniAdi { get; set; }
public int Kapasite { get; set; }
public int Ad { get; set; }
}
And then use it in your query, instead of anonymous objects:
public List<A> SiniflariListele()
{
var siniflar = (from s in db.Siniflar
join o in db.Ogretmenler
on s.OgretmenId equals o.OgretmenId
select new A {
SinifId = s.SinifId,
SinifAdi = s.SinifAdi,
Kapasite = s.Kapasite,
Ad = o.Ad
}).ToList();
return siniflar;
}
You could do the same with an existing class (e.g. Siniflar), but you have to be sure that this class has all necessary properties.
Rather than using new { property1, property2 }, create new Siniflar's in your select.
E.g.
select new Siniflar() {
SinifId = s.SinifId,
SinifAdi = s.SinifAdi,
Kapasite = s.Kapasite }).ToList()
Note: as lazyberezovsky mentioned, your mapping seems to be flawed, as Siniflar does not contain the property Ad.

How can I add more than 2 conditions to the LlNQ where clause?

I have a LINQ query with more than 2 where conditions, but it doesn't seem to evaluate with more than 2 conditions. Is there a way to add more conditions to the where clause?
var query =
from f in XElement.Load(MapPath("flightdata3.xml")).Elements("flight")
where (string)f.Element("departurelocation") == From &&
(string)f.Element("destinationlocation") == DestCity &&
(string)f.Element("airline") == Airline
// && (string)f.Element("departuredate") == DepartDate &&
// (string)f.Element("departuretime")==DepartTime
//&& (string)f.Element("returndate")==ReturnDate &&
//(string)f.Element("returntime")==ReturnTime
orderby Convert.ToInt32(f.Element("price").Value)
select new
{
FlightNumber = (Int32)f.Element("flightnumber"),
Airline = (string)f.Element("airline"),
Departure = (string)f.Element("departureairportsymbol"),
DepartTime = (string)f.Element("departuretime"),
Destination = (string)f.Element("destinationairportsymbol"),
ArrivalTime = (string)f.Element("arrivaltime"),
Stops = (int)f.Element("numberofstops"),
Duration = (string)f.Element("duration"),
Cabin = (string)f.Element("cabin"),
Price = "$" + (Int32)f.Element("price"),
ImagePath = (string)f.Element("airlineimageurl").Value
};
LINQ absolutely allows more than two WHERE conditions. Have you tried separating the query into more manageable pieces? LINQ uses deferred execution anyway so you won't see a performance penalty in doing so.
You should also consider making a class to hold the information you're stuffing into the result.
public class FlightDetail
{
public Int32 FlightNumber { get; set; }
public String Airline { get; set; }
public String Departure { get; set; }
public String DepartureTime { get; set; }
public String Destination { get; set; }
public String ArrivalTime { get; set; }
public Int32 Stops { get; set; }
public String Duration { get; set; }
public String Cabin { get; set; }
public Int32 Price { get; set; }
public String ImagePath { get; set; }
}
Then something like this which is more readable but should also help you find whatever bug is popping up.
var flights =
from f in XElement.Load(MapPath("flightdata3.xml")).Elements("flight")
select new FlightDetail
{
FlightNumber = (Int32)f.Element("flightnumber"),
Airline = (string)f.Element("airline"),
Departure = (string)f.Element("departureairportsymbol"),
DepartTime = (string)f.Element("departuretime"),
Destination = (string)f.Element("destinationairportsymbol"),
ArrivalTime = (string)f.Element("arrivaltime"),
Stops = (int)f.Element("numberofstops"),
Duration = (string)f.Element("duration"),
Cabin = (string)f.Element("cabin"),
Price = "$" + (Int32)f.Element("price"),
ImagePath = (string)f.Element("airlineimageurl").Value
};
var flightsByLocation =
flights.
where (string)f.Element("departurelocation") == From &&
(string)f.Element("destinationlocation") == DestCity
select new FlightDetail
{
FlightNumber = (Int32)f.Element("flightnumber"),
Airline = (string)f.Element("airline"),
Departure = (string)f.Element("departureairportsymbol"),
DepartTime = (string)f.Element("departuretime"),
Destination = (string)f.Element("destinationairportsymbol"),
ArrivalTime = (string)f.Element("arrivaltime"),
Stops = (int)f.Element("numberofstops"),
Duration = (string)f.Element("duration"),
Cabin = (string)f.Element("cabin"),
Price = "$" + (Int32)f.Element("price"),
ImagePath = (string)f.Element("airlineimageurl").Value
};
There shouldn't be an issue with having more then one condition. For example, you could have something like this from an Order table.
var orderDetails = (from o in context.OrderDetails
where o.OrderID == orderID
where o.OrderName == orderName
select o).ToList();

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