I have to join outer table column with inner table minimum value column
Here is my sql query:
SELECT O.Id, O.Name, O.Designation
FROM TableA AS O INNER JOIN
(SELECT MIN(SrNo) AS A_SNo, Id
FROM TableA
WHERE (Active = 1)
GROUP BY Id) AS I ON O.Id = I.Id AND O.SrNo = I.A_SNo AND O.Active = 1
I have tried this:
from tres in TableA join O in
(from tresp in TableA
where tresp.Active == true
group tresp by new { tresp.Id } into G
select new { Id = G.Key.Id, A_Sno =(int?)G.Min(X=>X.SrNo)}
) on new {tres.Id,a=(int?)tres.SrNo } equals new {O.Id,a=O.A_Sno } into tresss
where (tres.Active==true)
select new { tres.Id, tres.Name, tres.Designation }
in sql query I'm not getting duplicate rows but when i tried this in linq getting duplicate rows
try
from tres in TableA join O in
(from tresp in TableA
where tresp.Active == true
group tresp by new { tresp.Id } into G
select new { Id = G.Key.Id, A_Sno =(int?)G.Min(X=>X.SrNo)}
) on new {tres.Id,a=(int?)tres.SrNo } equals new {O.Id,a=O.A_Sno }
where (tres.Active==true)
select new {tres.Id,tres.Name,tres.Designation} into tresss
select new { tresss.Id, tresss.Name, tresss.Designation }
Related
SELECT *
FROM
ProcedureLookup ProcLookup
INNER JOIN (SELECT PatientProcedures.PP_ProcedureId, COUNT(*) as ProcCount
FROM (PatientProcedures INNER JOIN Treatments ON PatientProcedures.PP_TreatmentId = Treatments.TS_TreatmentId)
WHERE YEAR(Treatments.TS_Date) = YEAR(GETDATE())
GROUP BY PatientProcedures.PP_ProcedureId) cyearProc ON ProcLookup.PL_ProcedureId = cyearProc.PP_ProcedureId
ORDER BY ProcCount DESC;
Here ProcedureLookup, Treatments, PatientProcedures are the tables.
Here linq query.
var result = (from ProcLookup in db.ProcedureLookup
join cyearProc in (
from p in db.PatientProcedures
join t in db.Treatments on p.PP_TreatmentId equals
t.TS_TreatmentId
where
t.TS_Date.Year == DateTime.Now.Year
group p by p.PP_ProcedureId into g
select new
{
PP_ProcedureId = g.Key,
ProcCount = g.Count()
}
) on ProcLookup.PL_ProcedureId equals
cyearProc.PP_ProcedureId
orderby cyearProc.ProcCount descending
select new
{
// Columns
PP_ProcedureId = ProcLookup.PP_ProcedureId,
ProcCount = cyearProc.ProcCount
}).ToList();
I want to convert this sql query to linq
SELECT Students.StdId, Mark.Value
FROM Departments INNER JOIN
Mark ON Departments.DepId = Mark.DepId INNER JOIN
Students ON Departments.DepId = Students.DepId AND Mark.StdId = Students.StdId
I did this, but it's wont working
from s in Students
join d in Departments on s.DepId equals d.DepId
join m in Marks on new {s.StdId, d.DepId} equals new {m.StdId, m.DepId}
select new{
SId=s.StdId,
Value=m.Value
}
Lets try with
from s in Students
join d in Departments on s.DepId equals d.DepId
join m in Marks
on new {StdId = s.StdId, DepId = d.DepId} equals new {StdId = m.StdId, DepId= m.DepId}
select new{
SId=s.StdId,
Value=m.Value
}
How about
from s in Students
join m in Marks on s.StdId equals m.StdId
join d in Departments on m.DepId equals d.DepId
select new { s.StdId, m.Value };
I have a database where the tables are:
Table1:
Table1Id int
Table2:
Table2Id int
ForeignKeyToTable1 int
LookupTable:
Table2Id
Table3Id
Table3:
Table3Id int
Table3Field varchar
I want to:
select table1.* from table1
inner join table2 on table1.Table1Id = ForeignKeyToTable1
inner join LookupTable on LookupTable.Table2Id = table2.Table2Id
inner join Table3 on table3.Table3Id = LookupTable.Table3Id
where table3.Table3Field ='qwerty'
How can this be achieved in Linq?
var query =
from table1 in db.Table1
join table2 in db.Table2 on new { Table1Id = table1.Table1Id } equals new { Table1Id = table2.ForeignKeyToTable1 }
join lookuptable in db.LookupTable on table2.Table2Id equals lookuptable.Table2Id
join table3 in db.Table3 on lookuptable.Table3Id equals table3.Table3Id
where
table3.Table3Field == "qwerty"
select new {
table1.Table1Id
};
I believe something like this will go
var query = from t1 in context.Table1
join t2 in context.Table2
on t1.Table1Id equals t2.ForeignKeyToTable1
join lt in context.LookupTable
on t2.Table2Id equals lt.Table2Id
join t3 in context.Table3
on lt.Table3Id equals t3.Table3Id
where t3.Table3Field == "qwerty"
select t1;
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
};
I have Table1 and Table2 in the form of IEnumerable<DataRow>. Both the tables have columns Column1 and Column2.
I would like to do a left outer join on Column1 and would like to get a count of the rows present in Table2 and load the records into a DataTable.
I tried the following query
var query = from p in Table1
join q in Table2 on p.Field<string>("Column1") equals q.Field<string>("Column1") into pq
from xyz in pq.DefaultIfEmpty()
group xyz by new { Col1 = p.Field<string>("Column1"), Col2 = p.Field<string>("Column2") } into g
select dtFinalData.LoadDataRow(new object[]
{
g.Key.Col1,
g.Key.Col2,
g.Count
}, false);
Since the 'g' represents the grouped data the g.count returns 1 for rows which does not have entries in Table 2. I would like to return '0' for those rows.
Input :
Table 1
Col1Val1 Col2Val1
Col1Val2 Col2Val2
Table 2
Col1Val1 Col2Val1
Col1Val1 Col2Val1
Current Output :
Col1Val1 Col2Val1 2
Col2Val2 Col2Val2 1
Expected Results :
Col1Val1 Col2Val1 2
Col2Val2 Col2Val2 0
I have looked at LINQ - Left Join, Group By, and Count but I could not apply the same into my query ...
Can you help me fix this query ?
let it be so:
from p in Table1
let p1 = p.Field<string>("Column1")
let p2 = p.Field<string>("Column2")
let qs =
from q in Table2
where p1 == q.Field<string>("Column1")
select q
let qCount = qs.Count()
select dtFinalData.LoadDataRow(new object[]
{
p1,
p2,
qCount
}, false);
Since I didn't join, I don't have to group. Each result row corresponds to a row in Table1.
Here's a GroupJoin solution:
from p in Table1
let pkey = new { c1 = p.Field<string>("Column1"), c2 = p.Field<string>("Column2") }
join q in Table2 on pkey equals
new { c1 = q.Field<string>("Column1"), c2 = q.Field<string>("Column2") }
into qs
select dtFinalData.LoadDataRow(new object[]
{
pkey.c1,
pkey.c2,
qs.Count()
}, false);
And here's a Join and Group solution.
from p in Table1
let pkey = new { c1 = p.Field<string>("Column1"), c2 = p.Field<string>("Column2") }
join q in Table2 on pkey equals
new { c1 = q.Field<string>("Column1"), c2 = q.Field<string>("Column2") }
into right
from q in right.DefaultIfEmpty()
group q by pkey into g
select dtFinalData.LoadDataRow(new object[]
{
g.Key.c1,
g.Key.c2,
g.Count(q => q != null)
}, false);