I have 2 classes A and B, in which I wish to perform a linq query returning the class A (with all its members) along with a field from B.
Here is the class in which I'm returning:
public partial class A
{
// fields in A
public int classID { get; set; }
public string mem_1A { get; set; }
public string mem_2A { get; set; }
public int points { get; set; }
// ...
}
Here is the class in which I'm joining against:
public partial class B
{
// fields in B
public int classID { get; set; }
public string mem_1B { get; set; }
public string mem_2B { get; set; }
public int points { get; set; }
// ...
}
I've attempted the following variations but I wasn't able to get it working.
var db = new MyDBContext();
IEnumerable<A> result1 =
from tblA in db.A
join tblB in db.B on tblA.classID equals tblB.classID
select tblA;
IEnumerable<A> result2 = db.A.Join(db.B, x => x.classID, y => y.classID,(x,y) => x);
I'm only get all the members in A, but my points variable in class A is empty. I know I need to perform an assignment from the points in B, but I don't know how to do. What is the proper way to do this?
You might try this:
var result1 =
from tblA in db.A
join tblB in db.B on tblA.classID equals tblB.classID
select new { ClassA = tblA, PointsOfB = tblB.points };
It will create an anonymous class that holds tblA and the points of tblB.
Update the current value:
var result1 =
(from tblA in db.A
join tblB in db.B on tblA.classID equals tblB.classID
select new { ClassA = tblA, PointsOfB = tblB.points }).ToArray(); // <-- note this....
foreach(var r in result1)
r.ClassA.points = r.PointsOfB;
IEnumerable<A> classAUpdated = result1.Select(a => a.ClassA);
Or in one line:
IEnumerable<A> classAList = db.A
.Join(db.B, a => a.classID, b => b.classID,(a,b) => new
{
ClassA = a,
PointsOfB = b.points
}).ToArray () // <---------- to persist it
.Select(ab =>
{
ab.ClassA.points = ab.PointsOfB;
return ab.ClassA;
});
But you should test it.
I assume that this is what you want
var result2 = db.A.Join(db.B, x => x.classID, y => y.classID,(x,y) =>
new{classA = x,
pontOfB = y.points });
if you want it in classA, try this
var result2 = db.A.Join(db.B, x => x.classID, y => y.classID,(x,y) =>
new classA {
classId = x.classId,
mem_1a = x.mem_1a,
mem_1b = x.mem_1b,
points = y.points });
Related
My question is, inside my join of IDs, is it possible to add another column with an ID?
This is what I am trying to do:
My Index:
var orders= db.Orders.ToList();
var colers = db.Colors.ToList();
var result = (from c in orders
join st in colers on c.ID_Orders equals st.id into table1
select new OrderWithColorsViewModel { order =c, colers = table1.ToList()
}).ToList();
return View(result);
My classes:
public partial class Orders
{
public int ID_Orders { get; set; }
public Nullable<System.DateTime> Data_Registo { get; set; }
public string Num_Encomenda { get; set; }
public string Ref_Cliente { get; set; }
}
public partial class Colors
{
public int ID_Orders { get; set; }
public int ID_Line_Color { get; set; }
public string Color{ get; set; }
}
public partial class Quantities
{
public int ID_Orders { get; set; }
public int ID_Line_Color { get; set; }
public int quantity{ get; set; }
}
Of what I am learning right now I have this from my join:
and:
But what I want (I think):
If i am wrong in thinking, correct me, thanks
I leave my solution here for those who need it
var result1 = (from o in order
join c in coler
on o.ID_Programa equals c.ID_Programa into co
group new { o, co } by o.ID_Programa into g
from i in g
select new { order = i.o, colors = i.co }).ToList();
var result2 = (from r1 in result1
from c in r1.colors
join q in quant
on new { orderId = c.ID_Programa, colorlineId = c.ID_Linha_Cor } equals new { orderId = q.ID_Programa, colorlineId = q.ID_Linha_Cor } into p1
from p in p1
join s in statu
on new { orderId = p.ID_Programa, colorlineId = p.ID_Linha_Cor } equals new { orderId = s.ID_Programa, colorlineId = s.ID_Linha_Cor } into q
group new ColorsAndQuantities { coler = c, quant = p1.ToList(), status = q.ToList() } by c.ID_Programa).ToList();
var result = (from r1 in result1
join m in fabric
on r1.order.ID_Programa equals m.ID_Programa into t
from t1 in t
join r2 in result2
on t1.ID_Programa equals r2.Key
select new OrdersColorsViewModel
{
order = r1.order,
malhas = t1,
colers = r2.ToList()
}).ToList();
What is the best practice to convert Sub Query into LINQ,
for example I use this following query :
select VerID = (select top 1 x.INTERNALPACKINGSLIPID from
CUSTPACKINGSLIPVERSION x where a.RECID = x.CUSTPACKINGSLIPJOUR
order by x.VERSIONDATETIME desc),
c.LINENUM, c.RECID, *
from CUSTPACKINGSLIPJOUR a inner join CUSTPACKINGSLIPTRANS c
on a.PACKINGSLIPID = c.PACKINGSLIPID
I simulated you database with classes to get the syntax correct. Make modifications as necessary. There is no best method. Some people like using Where instead of joins. I like joins.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace ConsoleApplication1
{
class Program
{
static void Main(string[] args)
{
List<CUSTPACKINGSLIPVERSIONs> CUSTPACKINGSLIPVERSION = new List<CUSTPACKINGSLIPVERSIONs>();
List<CUSTPACKINGSLIPJOURs> CUSTPACKINGSLIPJOUR = new List<CUSTPACKINGSLIPJOURs>();
List<CUSTPACKINGSLIPTRANSs> CUSTPACKINGSLIPTRANS = new List<CUSTPACKINGSLIPTRANSs>();
var VerId = (from vId in CUSTPACKINGSLIPVERSION
join slipId in CUSTPACKINGSLIPJOUR on vId.INTERNALPACKINGSLIPID equals slipId.RECID
join cId in CUSTPACKINGSLIPTRANS on vId.INTERNALPACKINGSLIPID equals cId.PACKINGSLIPID
select new { vid = vId, slipId = slipId, cId = cId })
.GroupBy(x => x.vid.VERSIONDATETIME)
.OrderBy(x => x.Key)
.FirstOrDefault()
.Select(x => new { linenum = x.cId.LINENUM, recid = x.cId.RECID })
.ToList();
}
}
public class CUSTPACKINGSLIPVERSIONs
{
public int INTERNALPACKINGSLIPID { get; set; }
public DateTime VERSIONDATETIME { get; set; }
}
public class CUSTPACKINGSLIPJOURs
{
public int RECID { get; set; }
public int PACKINGSLIPID { get; set; }
}
public class CUSTPACKINGSLIPTRANSs
{
public int PACKINGSLIPID { get; set; }
public int LINENUM { get; set; }
public int RECID { get; set; }
}
}
You have this in your query and I am assuming it is a typo: a.RECID = x.CUSTPACKINGSLIPJOUR because CUSTPACKINGSLIPJOUR is the collection name. Therefore, I used SomeId instead. But this should give you the idea:
Do a subquery within the projection. You will also need to order by descending and then take the first record-this will be like top 1. Here is the query:
var query = from a in CUSTPACKINGSLIPJOUR
join c in CUSTPACKINGSLIPTRANS on a.PACKINGSLIPID equals c.PACKINGSLIPID
select new
{
VerID = (from x in CUSTPACKINGSLIPVERSION
where a.RECID == x.SomeId select x)
.OrderByDescending(o => o.VERSIONDATETIME)
.First().INTERNALPACKINGSLIPID,
c.LINENUM,
c.RECID
};
You can test it with the following collections:
var CUSTPACKINGSLIPJOUR = new List<CUSTPACKINGSLIPJOUR> { new CUSTPACKINGSLIPJOUR { PACKINGSLIPID = 1, RECID = 1 },
new CUSTPACKINGSLIPJOUR { PACKINGSLIPID = 2, RECID = 2 }};
var CUSTPACKINGSLIPTRANS = new List<CUSTPACKINGSLIPTRANS>
{
new CUSTPACKINGSLIPTRANS { LINENUM = 1, RECID = 1, PACKINGSLIPID = 1 }
};
var CUSTPACKINGSLIPVERSION = new List<CUSTPACKINGSLIPVERSION>
{
new CUSTPACKINGSLIPVERSION { INTERNALPACKINGSLIPID = 1, SomeId = 1, VERSIONDATETIME = DateTime.Today.AddDays(-1) },
new CUSTPACKINGSLIPVERSION { INTERNALPACKINGSLIPID = 2, SomeId = 1, VERSIONDATETIME = DateTime.Today }
};
It will be the same query if you use a DbSet<T>.
Suppose you have those setup:
public class TBL_CUSTPACKINGSLIPVERSION
{
public int CUSTPACKINGSLIPVERSION_ID { get; set; }
public int INTERNALPACKINGSLIPID { get; set; }
public DateTime VERSIONDATETIME { get; set; }
}
public class TBL_CUSTPACKINGSLIPJOUR
{
public int RECID { get; set; }
public int PACKINGSLIPID { get; set; }
}
public class TBL_CUSTPACKINGSLIPTRANS
{
public int PACKINGSLIPID { get; set; }
public int LINENUM { get; set; }
public int RECID { get; set; }
}
var CUSTPACKINGSLIPVERSION = new List<TBL_CUSTPACKINGSLIPVERSION>();
var CUSTPACKINGSLIPJOUR = new List<TBL_CUSTPACKINGSLIPJOUR>();
var CUSTPACKINGSLIPTRANS = new List<TBL_CUSTPACKINGSLIPTRANS>();
Then you can setting up the combined query as given in example below (assumed CUSTPACKINGSLIPVERSION_ID is the identity key which used in comparison between CUSTPACKINGSLIPJOUR & CUSTPACKINGSLIPTRANS):
var query = (from a in CUSTPACKINGSLIPJOUR
join c in CUSTPACKINGSLIPTRANS
on a.PACKINGSLIPID equals c.PACKINGSLIPID
select new {
VerID = (from x in CUSTPACKINGSLIPVERSION
where a.RECID == x.CUSTPACKINGSLIPVERSION_ID // should be an identity column/primary key to compare with
orderby x.VERSIONDATETIME descending
select x).FirstOrDefault().INTERNALPACKINGSLIPID,
c.LINENUM,
c.RECID
}).ToList();
Note that your query includes * at the end of SELECT statement which may indicate the query will return all records from both tables involved in join clause. If you want to return entire records of CUSTPACKINGSLIPJOUR only but not return all CUSTPACKINGSLIPTRANS, include a into the select new statement (incorporates SQL usage of a.*):
select new {
VerID = (from x in CUSTPACKINGSLIPVERSION
where a.RECID == x.CUSTPACKINGSLIPVERSION_ID // should be an identity column/primary key to compare with
orderby x.VERSIONDATETIME descending
select x).FirstOrDefault().INTERNALPACKINGSLIPID,
c.LINENUM,
c.RECID,
a // used if you want to return all records from CUSTPACKINGSLIPJOUR
}).ToList();
I want to to make a list of the object MyProduct the problem is when i map the child objects to the parent object
My code looks like this
ShopDatabaseEntities db = new ShopDatabaseEntities();
var Result1 = (from Products in db.Products
join ProductProperties in db.ProductProperties on Products.ProductId equals ProductProperties.ProductId
join Properties in db.Properties on ProductProperties.PropertyId equals Properties.PropertyId
select new
{
Products.ProductName,
Products.ProductPrice,
ProductProperties.PropertyValue,
Properties.PropertyName,
ProductProperties.PropertyId
}).ToList();
List<MyProduct> lii = new List<MyProduct>();
foreach (var item in Result1)
{
MyProduct pp = new MyProduct();
pp = (from c in Result1
select new MyProduct { Name = item.ProductName }).First();
MyProperty e = new MyProperty();
e.PropertyName = item.PropertyName;
e.PropertyValue = item.PropertyValue;
pp.pros.Add(e);
lii.Add(pp);
}
It seems to me that this is more what you want:
var query =
from Products in db.Products
join ProductProperties in db.ProductProperties on Products.ProductId equals ProductProperties.ProductId
join Properties in db.Properties on ProductProperties.PropertyId equals Properties.PropertyId
select new
{
ProductProperties.PropertyValue,
Properties.PropertyName,
ProductProperties.PropertyId,
Products.ProductName,
Products.ProductPrice
};
List<MyProduct> lii =
query
.ToArray()
.GroupBy(x => new
{
x.ProductName,
x.ProductPrice
}, x => new
{
x.PropertyValue,
x.PropertyName,
x.PropertyId
})
.Select(x => new MyProduct()
{
Name = x.Key.ProductName,
pros = x
.Select(y => new MyProperty()
{
PropertyName = y.PropertyName,
PropertyValue = y.PropertyValue,
})
.ToList()
})
.ToList();
BTW, this is the code that you should have included in your question to make answering much easier:
public class ShopDatabaseEntities
{
public List<MyProduct> Products = new List<MyProduct>();
public List<MyProductProperty> ProductProperties = new List<MyProductProperty>();
public List<MyProperty> Properties = new List<MyProperty>();
}
public class MyProduct
{
public int ProductId;
public string Name;
public string ProductName;
public decimal ProductPrice;
public List<MyProperty> pros = new List<MyProperty>();
}
public class MyProductProperty
{
public int ProductId;
public int PropertyId;
public double PropertyValue;
}
public class MyProperty
{
public int PropertyId;
public string PropertyName;
public double PropertyValue;
}
Type defs help immensely.
I'm new in ASP, Entity and lambda expressions. How can I join two tables?
Route Model:
public partial class Route
{
public Route()
{
Flights = new HashSet<Flight>();
}
public int RouteID { get; set; }
public int DepartureAirportID { get; set; }
public int ArrivalAirportID { get; set; }
public int FlightDuration { get; set; }
public virtual Airport Airport { get; set; }
public virtual Airport Airport1 { get; set; }
public virtual ICollection<Flight> Flights { get; set; }
}
Airport Model:
public partial class Airport
{
public Airport()
{
Routes = new HashSet<Route>();
Routes1 = new HashSet<Route>();
}
public int AirportID { get; set; }
public string City { get; set; }
public string Code { get; set; }
public virtual ICollection<Route> Routes { get; set; }
public virtual ICollection<Route> Routes1 { get; set; }
}
SQL query looks like this:
SELECT a.AirportID, a.City
FROM Route r INNER JOIN Airport a ON r.ArrivalAirportID = a.AirportID
WHERE r.DepartureAirportID = #departureAirportID
ORDER BY a.City
Sorry for this easy question but I don't know how to do this with Entity Framework...
Something like this should do (untested and just going on from your query) with a variable hard-coded):
using (var db = new YourDbContext())
{
var query = from r in db.Route
join a in db.Airport a on r.ArrivalAirportID equals a.AirportID
where r.DepartureAirportID = 1 // replace with your varialble.
orderby a.City
select a;
}
Include with join entity framework. here doctorSendAnswerModel also a inner table.
var data = _patientaskquestionRepository.Table.Include(x=>x.DoctorSendAnswer).Join(_patientRepository.Table, a => a.PatientId, d => d.Id, (a, d) => new { d = d, a = a }).Where(x => x.a.DoctorId == doctorid);
if(!string.IsNullOrEmpty(status))
data=data.Where(x=>x.a.Status==status);
var result = data.Select(x => new {x= x.a,y=x.d }).ToList();
var dt = result.Select(x => new PatientAskQuestionModel()
{
PatientId = x.x.PatientId.Value,
AskQuestion = x.x.AskQuestion,
Id = x.x.Id,
DoctorId = x.x.DoctorId,
FileAttachment1Url = x.x.FileAttachment1,
DocName = x.y.FirstName + " " + x.y.LastName,
CreatedDate = x.x.CreatedDate.Value,
doctorSendAnswerModel = x.x.DoctorSendAnswer.Select(t => new DoctorSendAnswerModel { Answer = t.Answer }).ToList()
}).ToList();
return dt;
LinQ query:
from r in context.Route
join a in context.Airport
on r.ArrivalAirportID equals a.AirportID
WHERE r.DepartureAirportID = "value"
ORDER BY a.City
select a.AirportID, a.City
var balance = (from a in context.Airport
join c in context.Route on a.ArrivalAirportID equals c.AirportID
where c.DepartureAirportID == #departureAirportID
select a.AirportID)
.SingleOrDefault();
You can do the following:
var matches = from a in context.Airports
join r in context.Routes
on a.AirportID equals r.ArrivalAirportID
where r.DepartureAirportID = departureAirportID
order by a.City
select new
{
a.AirportID,
a.City
};
Entity query with conditional join with pagination.
if (pageIndex <= 0)
pageIndex = 1;
pageIndex = ((pageIndex - 1) * pageSize) ;
var patient = _patientRepository.Table.Join(_DoctorPatient.Table.Where(x => x.DoctorId == Id && x.IsBlocked==false), x => x.Id, d => d.PatientId, (x, d) => new { x = x });
if (state != "")
patient = patient.Where(x => x.x.State.Contains(state));
if (name != "")
patient = patient.Where(x => (x.x.FirstName + x.x.LastName).Contains(name));
if (sdate != null)
patient = patient.Where(x => x.x.CreatedDate >= sdate);
if (eDate != null)
patient = patient.Where(x => x.x.CreatedDate <= eDate);
var result = patient.Select(x => x.x).Select(x => new PatientDoctorVM() { PatientId = x.Id, Id = x.Id, FirstName = x.FirstName, LastName = x.LastName, SSN = x.NewSSNNo, UserProfileId = x.UserProfileId, Email = x.Email, TumbImagePath = x.TumbImagePath }).OrderBy(x => x.Id).Skip(pageIndex).Take(pageSize).ToList();
Your entity and lembda query will be lool like this:
return (from d in _doctorRepository.Table
join p in _patientDoctor.Table on d.Id equals p.DoctorId
where p.PatientId == patientid.Value select d
).ToList();
Take a look at this site, it will explain you how the join works in Linq.
So if you ever need it again you will be able to solve it yourself.
I have the following SQL query
Select cLedgerName,dDateFrom,cPeriodType,nPeriodFrom,nPeriodTo
from sys_Account_Ledger a,sys_Log_Deposits_Interest_Master b
where a.cGLCode=b.cGLCode and b.dDateFrom='08-11-2012' and b.cPeriodType='Days'
I wanted to write this query using Lambda expression.This is where I am stuck.
public IList<ListViewData> GetDepositsListViewData(string glCode, string effectDate, string periodType)
{
using (var db = new DataClasses1DataContext())
{
var data=db.sys_Account_Ledgers.Join(db.sys_Log_Deposits_Interest_Masters,
ledger=>ledger.cGLCode,
deposits=>deposits.cGLCode,
(ledger,deposits)=>new {db.sys_Account_Ledgers =ledger,db.sys_Log_Deposits_Interest_Masters =deposits})
}
}
I have created a class which will be the return type of my query.
Here is the class
public class ListViewData
{
public string LedgerName { get; set; }
public string DateFrom { get; set; }
public string PeriodType { get; set; }
public int PeriodFrom { get; set; }
public int PeriodTo { get; set; }
}
Can anyone help me out with the lambda expression?
var result = dataContext.SysAccountLedger
.Join(dataContext.SysLogDepositsInterestMaster,
a => a.cGlCode,
b => b.cGlCode,
(a, b) => new ListViewData
{
LedgerName = a.LedgerName,
DateFrom = b.DateFrom,
PeriodType = b.PeriodType
// other properties
})
.Where(item => item.DateFrom = Convert.ToDateTime("08-11-2012") &&
item.PeriodType == "Days")
.ToList();
//Direct translation into Linq:
var query = from a in db.sys_Account_Ledger
join b in db.sys_Log_Deposits_Interest_Master on a.cGLCode equals b.cGLCode
where b.dDateFrom == Convert.ToDateTime("08-11-2012") && b.cPeriodType == "Days"
select new { a, b };
//Lambda of this:
var query = db.sys_AccountLedger
.Join(db.sys_Log_Deposits_Interest_Master,
a => a.cGLCode,
b => b.cGLCode,
(a, b) => new {a , b})
.Where(w => w.dDateFrom == Convert.ToDateTime("08-11-2012") && w.cPeriodType == "Days");