I have this query in SQL, and I want it to implement it in LINQ using Entity Framework, but how can I apply multiple tables left outer joins?
SELECT p.BookMastId as mastId
FROM BookMast p
left outer JOIN (SELECT y.BookMastId as Id, t.VrsnMastId as vrsn FROM BookReceiptMast t
left outer JOIN BookReceiptDtl y
on t.BookReceiptMastId = y.BookReceiptMastId) s
on p.BookMastId = s.Id where s.vrsn = 2
you can just use from var in collection join in syntax, something like this:
using(var cxt = new YourDataBaseContext()){
var firstJoin = from t in cxt.BookReceiptMast
join y in cxt.BookReceiptDtl
on t.BookReceiptMastId equals y.BookReceiptMastId
into yTemp
from y in yTemp.DefaultIfEmpty()
select new
{
Id = y != null ? y.BookMastId : 0,
vrsn = t.VrsnMastId
};
var allTables = from p in cxt.BookMast
join s in firstJoin
on p.BookMastId equals s.Id
into sTemp
from s in sTemp
where s.vrsn == 2
select new
{
mastId = p.BookMastId
};
}
I hope it helps you.
Related
I managed to turn this SQL query:
SELECT c.carId, c.Codename, count(c.CarId) as [CarCount],
FROM [DbEfTesting].[dbo].[Cars] c
left join Accessories a on c.CarId = a.CarId
left join CarsPeople cp on cp.CarId = c.CarId
left join People p on cp.PersonId = p.PersonId
group by c.CarId, c.Codename
into a LINQ query:
var x = from c in _context.Cars
join a in _context.Accessories on c.CarId equals a.Car.CarId
join j in _context.CarsPeople on c.CarId equals j.CarId
join p in _context.People on j.PersonId equals p.PersonId
group c by new { c.CarId, c.Codename } into g
select new VMCarAggregate()
{
CarId = g.Key.CarId,
Codename = g.Key.Codename,
CarCount = g.Count()
};
But now I'm lost trying to include a max value e.g the SQL:
SELECT c.carId, c.Codename, count(c.CarId) as [CarCount], max(a.AccessoryId) ...
I googled it and found lots of answers for method syntax. If I were using method chain syntax, I know I could do something like this:
_context.Accessories.Max(a => a.AccessoryId);
but I can't figure out how to do the group by in method chain syntax so either:
How can I convert that query to method syntax?
or
How can I inject a select on the max a.AccessoryId in the LINQ query format?
Try the below code once:
var x = from c in _context.Cars
join a in _context.Accessories equals a.Car.CarId
join j in _context.CarsPeople on c.CarId equals j.CarId
join p in _context.People on j.PersonId equals p.PersonId
group new { c.CarId, c.Codename, a.AccesoryId } by new { c.CarId, c.Codename } into g
select new
{
CarId = g.Key.CarId,
Codename = g.Key.Codename,
CarCount = g.Count(),
MaxAccesory = g.Max(z => z.AccesoryId)
};
I want to using join method for the following queryin Linq To SQL
What works correctly:
var db = new DatabaseDataContext();
db.DeferredLoadingEnabled = false;
var q = from p in db.Persons
join c in db.Contacts on c.personId equal p.Id
join j in db.Jobs on j.personId equal p.Id
select SetPersonItems(p,c,j) ;
and what is SetPersonItems:
private Person SetPersonItems(Person p, Contact c, Job j)
{
p.Contact = c;
p.Job = j;
return p;
}
What I need:
Now I would like using of Join Method for the above query. Like:
var q = db.Persons.Join<......>(db.Contacts,...).Join<....>(db.Jobs,...).Select....
p.s. Later I will create a dynamic method for the above Multiple Join (Join methods)
I have these queries in SQL and LINQ that were built to retrieve the same data. Unfortunately they are retrieving different amount of records (LINQ returns 1555 values, and SQL returns 1969) and I can't figure out why.
Please help me to find out what I'm missing. Follows the queries:
SQL:
SELECT l.Lease_Detail_ID, l.Lease_ID, l.XRef_Lease_ID, v.Vendor_Name, l.Description, c.County, l.Amount, l.Payment_Due_Date,
l.Lease_Type, l.Location_ID, l.Active, l.Expiration_Date, a.Authorized, p.Payment_Date
FROM tblfLeaseDetail AS l
LEFT JOIN tblvVendor AS v ON l.Vendor_ID = v.Vendor_ID
LEFT JOIN tblvCounty AS c ON l.County_ID = c.County_ID
LEFT JOIN tblfAuthorization AS a ON l.Lease_Detail_ID = a.Lease_Detail_ID
AND a.Authorization_ID = (SELECT TOP 1 Authorization_ID
FROM tblfAuthorization
WHERE Lease_Detail_ID = l.Lease_Detail_ID
ORDER BY Authorized_Date)
LEFT JOIN tblfPayment AS p ON l.Lease_Detail_ID = p.Lease_Detail_ID
AND p.Payment_ID = (SELECT TOP 1 Payment_ID
FROM tblfPayment
WHERE Lease_Detail_ID = l.Lease_Detail_ID
ORDER BY payment_date)
ORDER BY l.Lease_Detail_ID
LINQ: (Edited after a few comments)
var leaseList = (from l in leases.tblfLeaseDetails
join v in leases.tblvVendors on l.Vendor_ID equals v.Vendor_ID into lv
from jlv in lv.DefaultIfEmpty()
join c in leases.tblvCounties on l.County_ID equals c.County_ID into lc
from jlc in lc.DefaultIfEmpty()
join a in leases.tblfAuthorizations on l.Lease_Detail_ID equals a.Lease_Detail_ID into la
from jla in la.DefaultIfEmpty()
where jla.Authorization_ID == (from aj in leases.tblfAuthorizations
where aj.Lease_Detail_ID == l.Lease_Detail_ID
orderby aj.Authorized_Date ascending
select aj.Authorization_ID).FirstOrDefault()
join p in leases.tblfPayments on l.Lease_Detail_ID equals p.Lease_Detail_ID into lp
from jlp in lp.DefaultIfEmpty()
where jlp.Payment_ID == (from pj in leases.tblfPayments
where pj.Lease_Detail_ID == l.Lease_Detail_ID
orderby pj.Payment_Date ascending
select pj.Payment_ID).FirstOrDefault()
select new LeaseViewModel()
{
Lease_Detail_ID = l.Lease_Detail_ID,
Lease_ID = l.Lease_ID,
XRef_Lease_ID = l.XRef_Lease_ID,
Vendor_Name = jlv.Vendor_Name,
Description = l.Description,
County = jlc.County,
Amount = l.Amount,
Payment_Due_Date = l.Payment_Due_Date,
Lease_Type = l.Lease_Type.ToString(),
Location_ID = l.Location_ID,
Active = l.Active,
Expiration_Date = l.Expiration_Date,
Authorized = jla.Authorized,
Payment_Date = jlp.Payment_Date
});
EDIT:
After analyzing the run-time SQL query generated by LINQ statement I found out that it's creating the Authorized sub-query in the wrong place. Here is what it looks like:
SELECT [t0].[Lease_Detail_ID], [t0].[Lease_ID], [t0].[XRef_Lease_ID], [t1].[Vendor_Name] AS [Vendor_Name], [t0].[Description], [t2].[County] AS [County], [t0].[Amount], [t0].[Payment_Due_Date], [t0].[Expiration_Date], [t3].[Authorized] AS [Authorized], CONVERT(NVarChar(1),[t0].[Lease_Type]) AS [Lease_Type], [t0].[Location_ID], CONVERT(Int,[t0].[Active]) AS [Active], [t4].[Payment_Date] AS [Payment_Date]
FROM [dbo].[tblfLeaseDetail] AS [t0]
LEFT OUTER JOIN [dbo].[tblvVendor] AS [t1] ON [t0].[Vendor_ID] = ([t1].[Vendor_ID])
LEFT OUTER JOIN [dbo].[tblvCounty] AS [t2] ON [t0].[County_ID] = ([t2].[County_ID])
LEFT OUTER JOIN [dbo].[tblfAuthorization] AS [t3] ON ([t0].[Lease_Detail_ID]) = [t3].[Lease_Detail_ID]
LEFT OUTER JOIN [dbo].[tblfPayment] AS [t4] ON ([t0].[Lease_Detail_ID]) = [t4].[Lease_Detail_ID]
WHERE ([t4].[Payment_ID] = ((SELECT TOP (1) [t5].[Payment_ID] FROM [dbo].[tblfPayment] AS [t5] WHERE [t5].[Lease_Detail_ID] = ([t0].[Lease_Detail_ID])
ORDER BY [t5].[Payment_Date] )))
AND ([t3].[Authorization_ID] = (( SELECT TOP (1) [t6].[Authorization_ID]
FROM [dbo].[tblfAuthorization] AS [t6]
WHERE [t6].[Lease_Detail_ID] = ([t0].[Lease_Detail_ID])
ORDER BY [t6].[Authorized_Date] )))
The problem is that it only made more confuse, once Payment and Authorized joins have exactly the same structure.
after some research I finally found how to do it. Here is the LINQ query that generates the SQL I was trying to get:
var leaseList = (from l in leases.tblfLeaseDetails
join p in leases.tblfPayments
on l.Lease_Detail_ID equals p.Lease_Detail_ID into lp
from jlp in lp.Where(x => x.Payment_ID == (from pj in leases.tblfPayments
where pj.Lease_Detail_ID == l.Lease_Detail_ID
orderby pj.Payment_Date ascending
select pj.Payment_ID).FirstOrDefault()).DefaultIfEmpty()
join a in leases.tblfAuthorizations on l.Lease_Detail_ID equals a.Lease_Detail_ID into la
from jla in la.Where(x => x.Authorization_ID == (from aj in leases.tblfAuthorizations
where aj.Lease_Detail_ID == l.Lease_Detail_ID
orderby aj.Authorized_Date ascending
select aj.Authorization_ID).FirstOrDefault()).DefaultIfEmpty()
join v in leases.tblvVendors on l.Vendor_ID equals v.Vendor_ID into lv
from jlv in lv.DefaultIfEmpty()
join c in leases.tblvCounties on l.County_ID equals c.County_ID into lc
from jlc in lc.DefaultIfEmpty()
select new LeaseViewModel()
{
Lease_Detail_ID = l.Lease_Detail_ID,
Lease_ID = l.Lease_ID,
XRef_Lease_ID = l.XRef_Lease_ID,
Vendor_Name = jlv.Vendor_Name,
Description = l.Description,
County = jlc.County,
Amount = l.Amount,
Payment_Due_Date = l.Payment_Due_Date,
Lease_Type = l.Lease_Type.ToString(),
Location_ID = l.Location_ID,
Active = l.Active,
Expiration_Date = l.Expiration_Date,
Authorized = jla.Authorized,
Payment_Date = jlp.Payment_Date
});
I need to convert an SQL query to Linq/Lambda expression, I am trying doing the same but not getting the desired results.
SQL:
SELECT b.*, n.notes
FROM Goal_Allocation_Branch as b
INNER JOIN Goal_Allocation_Product as g
on b.Product = g.ProductID
and b.Year = g.Year
left join Goal_Allocation_Branch_Notes as n
on b.branchnumber = n.branch
and n.year = ddlYear
WHERE b.Year = ddlYear
and g.Show = 1
and branchnumber = ddlBranch
I am new to Linq , I am getting error on Join Clause , and X is not containing any data from first Join
var result = (from br in _DB_Branches.Goal_Allocation_Branches
join pr in _DB_Product.Goal_Allocation_Products on new { br.Product, br.Year } equals new {Product= pr.ProductID, Year= pr.Year }
join n in _DB_Notes.Goal_Allocation_Branch_Notes.Where(n => n.Year == ddlYear) on br.BranchNumber equals n.Branch into Notes
from x in Notes.DefaultIfEmpty()
select new BranchNotesViewModel
{
Year = x.Year,
BranchNumber = x.Branch,
ProductID = x.ProdID
}
).ToList();
Update: My First Join clause initially giving error "The type of one of the expression in Join Clause is incorrect " is resolved, when I Changed On Clause
from
"on new { br.Product, br.Year } equals new {pr.ProductID, pr.Year}"
"on new { br.Product, br.Year } equals new {Product=pr.ProductID,Year= pr.Year}"
still not getting desired results as expected from above SQL query. Please advise..
It should be something like this (see note):
var result =
(from br in _DB_Branches.Goal_Allocation_Branches
join pr in _DB_Product.Goal_Allocation_Products
on br.Product equals pr.ProductID
from n in _DB_Notes.Goal_Allocation_Branch_Notes.Where(x=>
x.branch == br.branchnumber
&& x.year == ddlYear
).DefaultIfEmpty()
where
br.Year == ddlYear
&& and br.Year == pr.Year
&& pr.Show == 1
&& br.branchnumber == ddlBranch
select new BranchNotesViewModel
{
Year = ...,
BranchNumber = ...,
ProductID = ...
}
).ToList();
Note: Change the select, to the properties you want.
Edit: fixed some syntax errors.
I finally figured out the correct answer. Working absolutely fine
var result = (from br in _DB_Branches.Goal_Allocation_Branches
join pr in _DB_Product.Goal_Allocation_Products on new { br.Product, br.Year } equals new { Product = pr.ProductID, Year = pr.Year }
join n in _DB_Notes.Goal_Allocation_Branch_Notes.Where(n=>n.Year==ddlYear) on br.BranchNumber equals n.Branch into Notes
where br.Year==ddlYear
&& pr.Show== true
&& br.BranchNumber==ddlBranch
from x in Notes.DefaultIfEmpty()
select new BranchNotesViewModel
{
Year=x.Year,
BranchNumber=x.Branch,
ProductID=br.Product,
Notes = x.Notes,
//All other fields needed
}
).ToList();
How can I use left outer join in LINQ for the following SQL query?
SELECT a.EventID, a.PrizeId, b.PrizeName, b.PrizeValue, c.FightID, c.Winnerid, c.WinnerName
FROM tblUserprize a
JOIN tblPrizeDetails b
ON a.PrizeId=b.PrizeId
LEFT OUTER JOIN tblWinnersList c
ON a.EventID=c.EventID AND a.PrizeId=c.PrizeId AND c.FightID = 1534
WHERE a.EventID = 1320
It should look like this:
var userPrize = (
from a in tblUserprize
join b in tblPrizeDetails on a.PrizeId equals b.PrizeId
join c in tblWinnersList on new { a.EventID, a.PrizeId } equals new { c.EventID, c.PrizeId } into joinedTables
from item in joinedTables.DefaultIfEmpty()
where a.EventID == 1320 && item.FightID == 1534
select new
{
a.EventID,
a.PrizeId,
b.PrizeName,
b.PrizeValue,
item.FightID,
item.Winnerid,
item.WinnerName
});