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();
Related
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.
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.
I have the below Linq query:
var qry = from Output in db.Outputs
join ShiftHours in db.ShiftHourses on Output.ShiftHour equals ShiftHours.ShiftHour
join ShiftData in db.ShiftDatas on Output.ShiftID equals ShiftData.ShiftID
where ShiftData.ShiftDate == date && ShiftData.Line == line
select new ProgressData()
{
CPM = ShiftData.CPM,
Target = ShiftData.Target,
CurrentOutput = db.Outputs.Sum(x=>x.Quantity),
PercentOfTarget = (db.Outputs.Sum(x=>x.Quantity) / ShiftData.Target) * 100
};
It is almost doing what I want but as it stands, the CurrentOutput lambda expression is returning the sum of the entire Quantity column of the Output table as I am unsure how to add in a 'Where' clause as well as the sum function (and hence the PercentOfTarget is also incorrect).
The where clause needs to be the same as the first where clause (date and line are parameters passed to the method):
where ShiftData.ShiftDate == date && ShiftData.Line == line
Can anyone help?
EDIT: Clarification of CurrentOutput.
In the 'Output' table there can be multiple records for a given 'ShiftData.ShiftDate' and 'ShiftData.Line' combination so I would like to calculate a sum of the 'Output' table 'Quantity' column values for a specified 'ShiftDate' and 'Line'
EDIT: Further clarification
This is some sample data from the Output table (OutputID is an auto-increment PK):
public class Output
{
[Key]
public int OutputId { get; set; }
public int ShiftID { get; set; }
public int Quantity { get; set; }
public int ShiftHour { get; set; }
public virtual ShiftData ShiftData { get; set; }
}
This is some sample data from the ShiftData table (ShiftID is an auto-increment PK, there will be more than one record for each date as further line numbers are added):
public class ShiftData
{
[Key]
public int ShiftID { get; set; }
public DateTime ShiftDate { get; set; }
public string Line { get; set; }
public int CPM { get; set; }
public double Target { get; set; }
}
So using the above sample data, I am trying to populate a ProgressData object:
public class ProgressData
{
public int CPM { get; set; }
public double Target { get; set; }
public int CurrentOutput { get; set; }
public double PercentOfTarget { get; set; }
}
Based on the sample data, I would expect my ProgressData object created for line 1 on 13/2/2014 to be populated as such:
CPM = 5, Target = 200, CurrentOutput = 120, PercentOfTarget = 60
You can try to do group join for that purpose :
var qry = from ShiftData in db.ShiftDatas
join Output in db.Outputs on ShiftData.ShiftID equals Output.ShiftID
into ShiftGroup
where ShiftData.ShiftDate == date && ShiftData.Line == line
select new ProgressData()
{
CPM = ShiftData.CPM,
Target = ShiftData.Target,
CurrentOutput = ShiftGroup.Sum(x=>x.Quantity),
PercentOfTarget = (ShiftGroup.Sum(x=>x.Quantity) / ShiftData.Target) * 100
};
Another thing, I can't see why you need to do join with ShiftHours here, since none of it's property used in select statement.
Just as #har07 posted I managed to get it working using the below. I am posting this for reference as it does answer the original question but I'm going to try and use #har07's code as it's tidier than mine.
var qry = (from Output in db.Outputs
join ShiftHours in db.ShiftHourses on Output.ShiftHour equals ShiftHours.ShiftHour
join ShiftData in db.ShiftDatas on Output.ShiftID equals ShiftData.ShiftID
where ShiftData.ShiftDate == date && ShiftData.Line == line
select new
{
ShiftData.ShiftDate,
ShiftData.Line,
ShiftData.CPM,
ShiftData.Target,
Output.Quantity
}).ToList();
var progress = qry.GroupBy(l => l.ShiftDate).Select(g => new ProgressData()
{
CPM = g.Where(c => c.ShiftDate == date && c.Line == line).Select(c => c.CPM).FirstOrDefault(),
Target = g.Where(c => c.ShiftDate == date && c.Line == line).Select(c => c.Target).FirstOrDefault(),
CurrentOutput = g.Where(c => c.ShiftDate == date && c.Line == line).Sum(c => c.Quantity),
PercentOfTarget = g.Where(c => c.ShiftDate == date && c.Line == line).Sum(c => (c.Quantity / c.Target) * 100)
});
return progress.FirstOrDefault();
This is my query, an it almost works. I need to add to this query " where(k.IdUser == d.UserDoc.
The problem appears when I add this. Wherever I put this it stops working. Join isn't option here.
var documents = (from d in DocumentDAO.GetDocument()
from k in UserDAO.GetUsers()
where (DateTime.Now <= d.ExpirationDate)
select new DocumentUI
{
Title = d.Title,
Description = d.Description,
DateOfAdd = d.DateOfAdd,
ExpirationDate = d.ExpirationDate,
UserDoc = d.UserDoc,
User = new UserUI {
FirstName = k.FirstName,
LastName = k.LastName}
}).ToList();
My app gets the data from database and show this data in window. If I start my app with this query ( I have only one documents in db) it shows me the same document but with all Users, and I want to my application shows me only this user who Id is as foreign key in documents (UserDoc).
I tried somethig like this:
var documents = (from d in DocumentDAO.GetDocument()
from k in UserDAO.GetUsers()
where ((DateTime.Now <= d.ExpirationDate) && (d.UserDoc == k.IdUser))
select new DocumentUI
{
Title = d.Title,
Description = d.Description,
DateOfAdd = d.DateOfAdd,
ExpirationDate = d.ExpirationDate,
UserDoc = d.UserDoc,
User = new UserUI {
FirstName = k.FirstName,
LastName = k.LastName}
}).ToList();
And:
var documents = (from d in DocumentDAO.GetDocument()
from k in UserDAO.GetUsers().Where(k => k.IdUser == d.UserDoc)
where (DateTime.Now <= d.ExpirationDate)
select new DocumentUI
{
Title = d.Title,
Description = d.Description,
DateOfAdd = d.DateOfAdd,
ExpirationDate = d.ExpirationDate,
UserDoc = d.UserDoc,
User = new UserUI {
FirstName = k.FirstName,
LastName = k.LastName}
}).ToList();
and in both case my app shows me nothing
this it class DocumentUI:
public class DocumentUI
{
public string Title { get; set; }
public string Description { get; set; }
public DateTime DateOfAdd { get; set; }
public DateTime ExpirationDate { get; set; }
public int UserDoc { get; set; }
public UserUI User { get; set; }
}
The below query (Same as your first Query) should return List<DocumentUI> provided you have proper data which satisfy ((DateTime.Now <= d.ExpirationDate) && (d.UserDoc == k.IdUser))
var documents = (from d in DocumentDAO.GetDocument()
join k in UserDAO.GetUsers()
on d.UserDoc equals k.IdUser
where (d.ExpirationDate >= DateTime.Now)
select new DocumentUI
{
Title = d.Title,
Description = d.Description,
DateOfAdd = d.DateOfAdd,
ExpirationDate = d.ExpirationDate,
UserDoc = d.UserDoc,
User = new UserUI {
FirstName = k.FirstName,
LastName = k.LastName}
}).ToList();
Still, If you are not getting result verify the values in Var documents = DocumentDAO.GetDocument(), var users = UserDAO.GetUsers().
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 :).