select colId,
colTaskType,
MaxID
from tblTaskType
join (
select tblCheckList.colTaskTypeID,
max(colItemNumber) MaxID
from tblCheckList
group by colTaskTypeID
) x on coltaskTypeID = tblTaskType.colID
Assuming you are using linq-to-sql and have the two tables in a datacontext.
The more or less exact translation would be:
var maxChecks = from checks in DataContext.tblChecklist
group checks by checks.colTaskTypeID into g
select new { colTaskTypeID, max = g.Group.Max(x => x.colItemNumber) };
var result = from t in DataContext.tblTaskType
join c in maxChecks on t.colTaskTypeID equals c.colTaskTypeID
select new { t.colId, t.colTaskTypeID, c.max };
But you could try:
var result = from t in DataContext.tblTaskType
select new {
t.colId,
t.colTaskTypeID,
Max = (from c in DataContext.tblChecklist
where c.colTaskTypeID == t.colTaskTypeID
select c.colItemNumber).Max() };
Related
I'd like to translate this SQL Query in LINQ with EF
SELECT Agts.AgtNum, Agts.AgtLastname, Agts.AgtFirstname, COUNT(Co.CoEnd) FROM [dbo].Agts AS Agts
INNER JOIN [dbo].[Contracts] AS Co ON Agts.AgtNum = Co.AgtNum
GROUP BY Agts.AgtNum, Agts.AgtLastname, Agts.Firstname
HAVING MAX(Co.CoEnd) <= '2020-05-17'
ORDER BY AgtNum asc
I tried that :
public List<AgentToPurge> AgentsToPurge(DateTime datePurge)
{
return (from agent in this.Entities.Agts
join contract in this.Entities.Contracts on agent.AgtNum equals contract.AgtNum
group agent by agent.AgtNum into g
where g.CoEnd <= datePurge
select new AgentToPurge
{
Id = g.Key,
Lastname = g.Key.AgtLastname,
Firstname = g.Key.AgtFirstname,
Contract_Deleted = g.Key.CoEnd.Count()
}).ToList();
}
But the line
where g.CoFin <= datePurge
doesn't work.
I think my "select new" isn't correct either.
Could you help me to solve this ?
Try the following query:
public List<AgentToPurge> AgentsToPurge(DateTime datePurge)
{
return (from agent in this.Entities.Agts
join contract in this.Entities.Contracts on agent.AgtNum equals contract.AgtNum
group contract by new { agent.AgtNum, agent.AgtLastname, agent.AgtFirstname } into g
where g.Max(x => x.CoEnd) <= datePurge
select new AgentToPurge
{
Id = g.Key.AgtNum,
Lastname = g.Key.AgtLastname,
Firstname = g.Key.AgtFirstname,
Contract_Deleted = g.Sum(x => x.CoEnd != null ? 1 : 0)
}).ToList();
}
Note that LINQ query is built from classes and navigation properties and probably you will not need JOIN, if you have properly defined Model.
I have a situation where two tables should be joined with multiple columns with or condition. Here, I have a sample of sql query but i was not able to convert it into linq query.
select cm.* from Customer cm
inner join #temp tmp
on cm.CustomerCode = tmp.NewNLKNo or cm.OldAcNo = tmp.OldNLKNo
This is how i have write linq query
await (from cm in Context.CustomerMaster
join li in list.PortalCustomerDetailViewModel
on new { OldNLKNo = cm.OldAcNo, NewNLKNo = cm.CustomerCode } equals new { OldNLKNo = li.OldNLKNo, NewNLKNo = li.NewNLKNo }
select new CustomerInfoViewModel
{
CustomerId = cm.Id,
CustomerCode = cm.CustomerCode,
CustomerFullName = cm.CustomerFullName,
OldCustomerCode = cm.OldCustomerCode,
IsCorporateCustomer = cm.IsCorporateCustomer
}).ToListAsync();
But this query doesn't returns as expected. How do I convert this sql query into linq.
Thank you
You didn't tell if list.PortalCustomerDetailViewModel is some information in the database, or in your local process. It seems that this is in your local process, your query will have to transfer it to the database (maybe that is why it is Tmp in your SQL?)
Requirement: give me all properties of a CustomerMaster for all CustomerMasters where exists at least one PortalCustomerDetailViewModel where
customerMaster.CustomerCode == portalCustomerDetailViewModel.NewNLKNo
|| customerMaster.OldAcNo == portalCustomerDetailViewModel.OldNLKNo
You can't use a normal Join, because a Join works with an AND, you want to work with OR
What you could do, is Select all CustomerMasters where there is any PortalCustomerDetailViewModel that fulfills the provided OR:
I only transfer those properties of list.PortalCustomerDetailViewModel to the database that I need to use in the OR expression:
var checkProperties = list.PortalCustomerDetailViewModel
.Select(portalCustomerDetail => new
{
NewNlkNo = portalCustomerDetail.NewNlkNo,
OldNLKNo = portalCustomerDetail.OldNLKNo,
});
var result = dbContext.CustomerMasters.Where(customerMaster =>
checkProperties.Where(checkProperty =>
customerMaster.CustomerCode == checkProperty.NewNLKNo
|| customerMaster.OldAcNo == checkProperty.OldNLKNo)).Any()))
.Select(customerMaster => new CustomerInfoViewModel
{
Id = customerMaster.Id,
Name = customerMaster.Name,
...
});
In words: from each portalCustomerDetail in list.PortalCustomerDetailViewModel, extract the properties NewNKLNo and OldNLKNo.
Then from the table of CustomerMasters, keep only those customerMasters that have at least one portalCustomerDetail with the properties as described in the OR statement.
From every remaining CustomerMasters, create one new CustomerInfoViewModel containing properties ...
select cm.* from Customer cm
inner join #temp tmp
on cm.CustomerCode = tmp.NewNLKNo or cm.OldAcNo = tmp.OldNLKNo
You don't have to use the join syntax. Adding the predicates in a where clause could get the same result. Try to use the following code:
await (from cm in Context.CustomerMaster
from li in list.PortalCustomerDetailViewModel
where cm.CustomerCode == li.NewNLKNo || cm.OldAcNo = li.OldNLKNo
select new CustomerInfoViewModel
{
CustomerId = cm.Id,
CustomerCode = cm.CustomerCode,
CustomerFullName = cm.CustomerFullName,
OldCustomerCode = cm.OldCustomerCode,
IsCorporateCustomer = cm.IsCorporateCustomer
}).ToListAsync();
var result=_db.Customer
.groupjoin(_db.#temp ,jc=>jc.CustomerCode,c=> c.NewNLKNo,(jc,c)=>{jc,c=c.firstordefault()})
.groupjoin(_db.#temp ,jc2=>jc2.OldAcNo,c2=> c2.OldNLKNo,(jc2,c2)=>{jc2,c2=c2.firstordefault()})
.select(x=> new{
//as you want
}).distinct().tolist();
How can I convert below SQL to lambda or LINQ?
with cte
as (select * from test1
union all
select * from test2)
select * from cte
union all
select sum(columnA),sum(columnB),sum(columnC) from cte
In Linq UNION ALL is .Concat(), so:
var cte = test1.Concat(test2);
var sums = new MyModel
{
columnA = cte.Sum(c => c.columnA),
columnB = cte.Sum(c => c.columnB),
columnC = cte.Sum(c => c.columnC),
}
return cte.Concat(IEnumerable.Repeat(sums, 1));
You must remember that test1 and test2 must be type MyModel and MyModel contains only columnA, columnB and columnC.
I put two tables together in one datagridvie but in the last row of datagridview I need the total for both tables in the country, I can do one row in total for one table and another row for the other table I also don't need it, like I can only have one line with the total of both tables.
DataContex db = new DataContex();
var query = (
from v1 in db.View1
where shf.Date >= dpDate.Value && shf.Date <= dpDate1.Value
select new
{
v1.Name,
v1.Date,
v1.Quality,
v1.Rat,
v1.Total
}
).Concat
(
from v2 in db.View2
where f.Date >= dpDate.Value && f.Date <= dpDate1.Value
select new
{
v2.Name,
v2.Date,
v2.Quality,
v2.Rat,
v2.Total
}
).Concat
(from View2 in
(from v2 in db.View2
where v2.Date >= dpDate.Value && sh.Date <= dpDate1.Value
select new
{
v2.Name,
v2.Date,
v2.Quality,
v2.Rate,
v2.Total
})
group v2 by new { v2.NRFA } into g
select new
{
Name = "Total:",
Date = dpDate1.Value,
Quality = (decimal?)g.Sum(p => p.Quality),
Rate = (decimal?)g.Sum(p => p.Rate),
Total = (decimal?)g.Sum(p => p.Total)
}
);
Blockquote
I am a newbie intern way over my head, I promise I have researched this thoroughly and tried many different things. The following linq query works, but I want to group rows by last and first name and then only show the rows that appear more than once. When I un-comment out the group by statement, all my aliases below become unrecognized and changing them to the actual db.table names doesn't help.
var query = from emps in db.Employees
join c in db.Cards on emps.SbiID equals c.SbiID
where c.StateID == 0 && c.CardNumberNumeric > 100000
//group emps by new {emps.Surname, emps.Name};
//orderby grp.Count() // something like 'where grp.Count > 1
select new
{
Surname = emps.Surname,
Name = emps.Name,
CorpID = emps.Identifier,
CardNum = c.CardNumber,
CostCenter = emps.EmployeeUserField.UF13,
Supervisor = (from e in db.Employees
where
e.Identifier.Equals(emps.EmployeeUserField.UF5)
select e.Surname).FirstOrDefault()
+ ", "
+ (from e in db.Employees
where e.Identifier.Equals(emps.EmployeeUserField.UF5)
select e.Name).FirstOrDefault(),
SupervisorID = emps.EmployeeUserField.UF5,
EmpCommence = emps.CommencementDateTime,
CardCommence = c.CommencementDateTime,
WorkPhone = emps.Telephone,
State = (from cf in db.ComboFields
from sp in db.StringProperties
where cf.ComboIndex.Equals(c.StateID)
&& cf.StringID.Equals(sp.StringID)
&& cf.TableName.Equals("Card")
&& cf.FieldName.Equals("StateID")
select sp.DefaultValue).FirstOrDefault()
};
this.tagsGridView.DataSource = query;
this.tagsGridView.DataBind();
I think the problem you're running into is that you're not flattening out your groups appropriately. For example:
var duplicateEmployees = db.Employees
.GroupBy(emp => emp, new EmployeeComparer())
.Where(grp => grp.Count() > 1)
.SelectMany(grp => grp.AsEnumerable());
var duplicateEmployeeInfo =
from emps in duplicateEmployees
join c in db.Cards on emps.SbiID equals c.SbiID
where c.StateID == 0 && c.CardNumberNumeric > 100000
select new
{
... what to select
};
With:
public class EmployeeComparer : IEqualityComparer<Employee>
{
public bool Equals(Employee x, Employee y)
{
return x.Surname == y.Surname && x.Name == y.Name;
}
public int GetHashCode(Employee obj)
{
unchecked { return (17 * obj.Surname.GetHashCode()) ^ (23 * obj.Name.GetHashCode()); }
}
}
This groups the employees by name, finds the groups that have a count > 1, then returns the elements of those groups. No guarantees on performance, but this should solve your issue.
var q = (from Labels in dc.tblArtworkDataLabels select Labels).ToList();
But I need this to do the quivalent of:
SELECT d.ID, d.labelID, d.dataID, d.data, l.templateID
FROM tblArtworkDataLabels AS d INNER JOIN
tblArtworkData AS l ON d.dataID = l.ID
WHERE (l.templateID = 238)
How do I do this in LINQ?
Edit
Sorry! Missed the WHERE clause on original statmenet!
var result = dc.tblArtworkDataLabels
.Join(dc.tblArtworkData, l => l.ID, d => d.dataID, (l, d) => new {l, d})
.Select(o => new {
Id = o.d.ID,
LabelId = o.d.labelID,
DataId = o.d.dataID,
Data = o.d.data,
TemplateId = o.l.templateID,
})
.Where(o => o.l.templateID == 238);
If you have a correct foreign key on tblArtworkData to the primary key on the tblArtworkDataLabels and have imported them correctly into the DBML designer you can have LINQ2SQL implicitly creating the join:
from l in tblArtworkData
where l.templateID = 238
select new {
Id = l.tblArtworkDataLabel.ID,
LabelId = l.tblArtworkDataLabel.labelID,
DataId = l.tblArtworkDataLabel.dataID,
Data = l.tblArtworkDataLabel.data,
TemplateId = l.templateID,
}
See my answer on the question "LINQ to SQL: Multiple joins ON multiple Columns. Is this possible?" for how the implicit join translates to SQL.
Edit:
In the case I misunderstood your relations and you have many tblArtworkDataLabels to one tblArtworkData you have to turn the query the other way around
from d in tblArtworkDataLabels
where d.tblArtworkData.templateID = 238
select new {
Id = d.ID,
LabelId = d.labelID,
DataId = d.dataID,
Data = d.data,
TemplateId = d.tblArtworkData.templateID,
}
try
var q = (from Labels in dc.tblArtworkDataLabels
join data in dc.tblArtworkData on Labels.ID equals data.DataID select Labels).ToList();