I want to convert this code to linq:
select t1.title, COUNT(*)as num
from t1 INNER join t2 on t2.gId = t1.Id
group by t1.title, t1.cId
having t1.cId = 2
I tried this below code:
from p in db.t1s join r in db.t2s on p.Id equals r.gId
where p.cId == 2
group p by p.title into g
select new{ name = from o in g select o.title, num = g.Count()}
But this doesn't return COUNT correctly.
please guide me how can I solve the problem
thanks
Without sample data its hard to get it right, but try this snippet
from p in db.t1s
join r in db.t2s on p.Id equals r.gId
where p.cId == 2
group p by new {p.title, p.cId} into grouped
select new{ name = grouped.Key.title, num = grouped.Count()}
Also, note that this sql:
select t1.title, COUNT(*)as num
from t1 INNER join t2 on t2.gId = t1.Id
group by t1.title, t1.cId
having t1.cId = 2
Will always return 1 as result of COUNT(*). The reason is that you have filtering t1.cId = 2 and grouping by t1.cId as second parameter.
Related
I am trying to convert this tSql command to linq query.
I want to group this columns.
Can you help me?
select vUnit.FK_Unit_ID , Unit.unitNumber, unit.unitTitle , title.featureTitleName
from unit.UnitFeatureValue vUnit
inner join unit.Unit on vUnit.FK_Unit_ID = Unit.ID
inner join unit.FeatureTitle title on vUnit.FK_FeatureTitle_ID = title.ID
where vUnit.FK_Unit_ID = 15 and title.canMoreSelect = 1
group by vUnit.FK_Unit_ID ,unit.unitNumber, unit.unitTitle , title.featureTitleName
var query = (
from v in dbContext.UnitFeatureValue
join u in dbContext.Unit on v.FK_Unit_ID equals u.ID
join t in dbContext.FeatureTitle on v.FK_FeatureTitle_ID equals t.ID
where v.FK_Unit_ID == 15 && t.canMoreSelect == 1
select new {
v.FK_Unit_ID,
u.unitNumber,
u.unitTitle,
t.featureTitleName,
}).Distinct();
something like this
var result = (from v in vUnit
join u in unit on v.FK_Unit_ID equals u.ID
join t in title on v.FK_FeatureTitle_ID equals t.ID
where v.FK_Unit_ID == 15 and t.canMoreSelect == 1
select new { v.FK_Unit_ID , u.unitNumber, u.unitTitle , t.featureTitleName }).ToList();
SELECT TOP (5)
Sales.Product, Sales.Product_Price, COUNT(*) AS CNT,
Products.Category, Products.IMG_URL, Products.Rate_Avg
FROM
Sales
INNER JOIN
Products ON Sales.Product = Products.Product
GROUP BY
Sales.Product, Sales.Product_Price,
Products.Category, Products.IMG_URL, Products.Rate_Avg
HAVING
(COUNT(*) > 1)
ORDER BY CNT DESC
Most of that query has a 1-to-1 correspondence to the equivalent linq-to-sql expression. Though the TOP (5) part needs to be added to the end.
(from s in db.Sales
join p in db.Products on s.Product equals p.Product
group s by new { s.Product, s.Product_Price, p.Category, p.IMG_URL, p.Rate_Avg } into g
where g.Count() > 1
orderby g.Count() descending
select new
{
g.Key.Product,
g.Key.Product_Price,
CNT = g.Count(),
g.Key.Category,
g.Key.IMG_URL,
g.Key.Rate_Avg,
}).Take(5)
I have a sql having left outer join, I want to convert it to linq. the sql is
Select P.Surname, P.Othername H.history
from customers P left outer join historyfiles H on H.patID = P.patId
and H.category1 = 4
where P.id = 2299
Thank you very much.
You can try this:
var query = from p in db.customers.Where(t => t.id == 2299 )
join h in db.historyfiles.Where(l => l.category1 == 4 ) on p.patID equals h.patID into gj
from h in gj.DefaultIfEmpty()
select new { p.Surname, p.Othername, h.History };
I've got a table called IssueStatuses and another table called Issues. Issues has a StatusID and SubStatusID, both of which are from the IssueStatuses table which has an additional field that states if it's a SubStatus or not, like so:
IssueStatuses
IssueStatusID
IssueStatus
IsSubStatus
I'm trying to get a list of SubStatuses for a particular list of Issues. In SQL it's:
SELECT iss.IssueStatus, COUNT(iss.IssueStatus) AS Total
FROM Issues AS Issues
INNER JOIN Rooms r ON Issues.RoomID = r.RoomID
INNER JOIN Locations l ON l.LocationID = r.LocationID
INNER JOIN Customers c ON l.CustomerID = c.CustomerID
INNER JOIN (SELECT * FROM IssueStatuses WHERE IsSubStatus = 0) ist ON Issues.IssueStatusID = ist.IssueStatusID
INNER JOIN (SELECT * FROM IssueStatuses WHERE IsSubStatus = 1) iss ON Issues.IssueSubStatusID = iss.IssueStatusID
WHERE c.Customer = 'ABC'
AND l.Location = 'MySite'
GROUP BY iss.IssueStatus
but I"m having trouble converting it to LINQ. The desired output would be something like:
IssueStatus | Total
-------------------
Open 15
Delayed 25
On Time 8
Here's what I've tried with LINQ:
var query = from i in Issues
join r in Rooms on i.RoomID equals r.RoomID
join l in Locations on r.RoomID equals l.LocationID
join c in Customers on l.CustomerID equals c.CustomerID
where i.IssueStatusID == (from ist in IssueStatuses
where ist.IsSubStatus == false
select ist)
&& i.IssueSubStatusID == (from iss in IssueStatuses
where iss.IsSubStatus == true
select iss)
&& c.Custome == "ABC"
&& l.Location == "MySite"
group i by i.IssueStatus
but I know it's wrong because LINQPad throws an error stating:
can't convert int to type Models.IssueStatus
What I need to do is use iss.IssueStaus to group on but I can't access it. Can someone tell me what I'm doing wrong?
How about this (untested but I should be close):
var query = from i in Issues
join r in Rooms on i.RoomID equals r.RoomID
join l in Locations on r.LocationID equals l.LocationID
join c in Customers on l.CustomerID equals c.CustomerID
join ist in IssueStatuses on i.IssueStatusID equals ist.IssueStatusID
join iss in IssueStatuses on i.IssueSubStatusID equals iss.IssueStatusID
where !ist.IsSubStatus && iss.IsSubStatus
&& c.Customer == "ABC"
&& l.Location == "MySite"
group i by iss.IssueStatus into g
select new {IssueStatus = g.Key, Total = g.Count()}
Your two inner from statements return objects and not IDs ... select the ID you need like ist.IssueStatusID:
var query = from i in Issues
join r in Rooms on i.RoomID equals r.RoomID
join l in Locations on r.RoomID equals l.LocationID
join c in Customers on l.CustomerID equals c.CustomerID
where (from ist in IssueStatuses
where ist.IsSubStatus == false
select ist.IssueStatusID).Contains(i.IssusStatusID)
&& (from iss in IssueStatuses
where iss.IsSubStatus == true
select iss.IssueStatusID).Contains(i.IssueSubStatusID)
&& c.Customer == "ABC"
&& l.Location == "MySite"
group i by i.IssueStatus
I have 3 tables which named Player, PlayerDetails and Team. I want to write a linq statement such as
from p in Player join d in PlayerDetails on p.ID equals d.PID
and then right join team table, Player has a column named TID which face to Team table's ID.
I have tried to write a statement like
from p in Player join d in PlayerDetails on p.ID equals d.PID into PlayerGroup
from t in team join g in PlayerGroup on t.ID equals g.p.ID
It certainly can't work. I'm not sure how to write such type of query statement, table left join table2 then right join table3.
Who can help?
I believe you could do something like this:
var LeftJoin =
from p in Player
join d in PlayerDetails on p.ID equals d.PID into pd
from d in pd.DefaultIfEmpty()
select new
{
pID = p.ID,
pTID = p.TID,
dID = d.ID
};
var RightJoin =
from t in Team
join l in LeftJoin on t.ID equals l.pTID into tl
from l in tl.DefaultIfEmpty()
select new
{
tID = t.ID,
pID = l.pID,
pTID = l.PTID,
dID = l.dID
};
To do everything in one query, I think you could do (not tested) something like this:
var RightJoin =
from t in Team
join l in
(from p in Player
join d in PlayerDetails on p.ID equals d.PID into pd
from d in pd.DefaultIfEmpty()
select new
{
pID = p.ID,
pTID = p.TID,
dID = d.ID
})
on t.ID equals l.pTID into tl
from l in tl.DefaultIfEmpty()
select new
{
tID = t.ID,
pID = l.pID,
pTID = l.PTID,
dID = l.dID
};