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Inner Join LINQ Without making a New Model [closed]

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I'm working with LINQ and I need to do a inner join. This is my code:
var requests =
(from request in db.Request
join estatus in db.typesStatus
on request.fkStatus equals estatus.idStatus
where request.fkStatus == status && DbFunctions.TruncateTime(request.dateRquest) == DbFunctions.TruncateTime(fecha)
select new { request = request, estatus = estatus.status, nombre = (String)UserAccessRequest.checkUserAsync(request.wiwMakeRequest, "name").Result })
.ToList();
I'm trying to call a method inside my LINQ query. This one calls an API and returns a string but I recieved the next error:
LINQ to Entities does not recognize the method
'System.Threading.Tasks.Task`1[System.Object]
checkUserAsync(System.String, System.String)' method, and this method
cannot be translated into a store expression.
Is any way to make the LINQ query without making a model to the result of this LINQ query?

Just call your method after LINQ query loaded data into memory:
var requests =
(from request in db.Request
join estatus in db.typesStatus
on request.fkStatus equals estatus.idStatus
where request.fkStatus == status && DbFunctions.TruncateTime(request.dateRquest) == DbFunctions.TruncateTime(fecha)
select new { request = request, estatus = estatus.status })
.ToList()
.Select(i => new { i.request, i.estatus, nombre = (String)UserAccessRequest.checkUserAsync(i.request.wiwMakeRequest, "name").Result })
.ToList()

how to use joining with LinQ To Entity [closed]

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I have this code
var value = (from dc in _context.ContractDetails
where dc.EmployeeID == id
select dc.Amount);
return value;
}
is it acceptable to do Value.Sum();

You want to return the sum it looks like. Instead of having query be a decimal, just let it be what it wants (var, it's really IEnumerable<decimal>). Then you can return an aggregate on that. Sum for example
var query = from emp in Employees
join cd in ContractDetails
on emp.EmployeeID equals cd.EmployeeID
where cd.EmployeeID == id
select cd.Amount;
return query.Sum();
If this is all it does, then I also feel like you don't need to join at all, and it would be simpler to do
var query = from cd in ContractDetails
where cd.EmployeeID == id
select cd.Amount;
return query.Sum();
... unless you were using the join to test for the existence of an employee in the Employee table as a condition.

Your linq statement results in an IQueryable<Amount>, you would need to take that result and call Sum() on it to get the result you're seeking.
First, isn't there a navigation property you can use (i.e. Employee.ContracteDetails) instead of manually joining the two sets? For example,
var sum = _context.Employee
.Where( e => e.Id == id )
.Select( e => e.ContractDetails.Sum( cd => cd.Amount ) )
.SingleOrDefault();
Second, you're not using any information you need from Employee, even your where clause references ContractDetails alone; why start your query there? Work with _context.ContractDetails instead:
var sum = _context.ContractDetails
.Where( cd => cd.EmployeeId == id )
.Sum( cd => cd.Amount );

How to write the below SQL query to LINQ query in C#? [closed]

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How to convert normal SQL to LINQ query? Is there tools that can do that?? Online Tools

Have you tried something like this (a few joins omitted for brevity):
var result = from s in TooltipsLanguage
join c in TooltipsLanguageSection on s.Id equals c.IdLanguage
join p in TooltipsSection on c.IdSection equals p.Id
join ...
select new MyDestinationObject()
{
Id = s.BusinessEntityID,
Language = s.Language,
IdLanguage = c.IdLanguage,
...
};

This meight be help you.
var temp= edbContext.TooltipsLanguage.select(
c=> new {
TooltipsLanguage.Id,
TooltipsLanguage.Language,
TooltipsLanguage.TooltipsLanguageSection.Id,
TooltipsLanguage.TooltipsLanguageSection.IdLanguage,
TooltipsLanguage.TooltipsLanguageSection.IdSection,
TooltipsLanguage.TooltipsLanguageSection.TooltipsSection.Id,
TooltipsLanguage.TooltipsLanguageSection.TooltipsSection.Section,
TooltipsLanguage.TooltipsLanguageSection.TooltipsSection.Section.TooltipsItem.Id,
TooltipsLanguage.TooltipsLanguageSection.TooltipsSection.Section.TooltipsItem.IdItem,
TooltipsLanguage.TooltipsLanguageSection.TooltipsSection.Section.TooltipsItem.TooltipsItemText.Id,
TooltipsLanguage.TooltipsLanguageSection.TooltipsSection.Section.TooltipsItem.TooltipsItemText.IdItem,
TooltipsLanguage.TooltipsLanguageSection.TooltipsSection.Section.TooltipsItem.TooltipsItemText.IdText,
TooltipsLanguage.TooltipsLanguageSection.TooltipsSection.Section.TooltipsItem.TooltipsItemText.TooltipsText.Id,
TooltipsLanguage.TooltipsLanguageSection.TooltipsSection.Section.TooltipsItem.TooltipsItemText.TooltipsText.Texts});

Convert SQL statement to LINQ with case condition [closed]

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I have a problem with converting a native select statement with CASE statement using LINQ.
This is the native SQL which is working in SQL Server :
select
v.vehl_ContainerNo as cont_name, v.vehl_Name,
v.vehl_drivername, v.vehl_entrancedate, v.vehl_customsdec,
c.Capt_AR as VehicleState,
case
when v.vehl_rampid is null
then ''
else (select ramp_Name
from Ramp
where ramp_RampID = v.vehl_rampid)
end as cont_rampid
from
Vehicle v, Custom_Captions c
where
v.vehl_state = c.Capt_Code
and c.Capt_Family = 'vehl_state'
and v.vehl_ClearanceCompany = 471
I want to get the ramp_name:
if vehl_rampid is null then return an empty string
else do another select statement to get the ramp_name from the ramp table where vehl_rampid equals ramp_rampid.
when i use the following linq statement:
//List<qryRslt> query = (from v in db.Vehicles
// join cus in db.Custom_Captions on v.vehl_state equals cus.Capt_Code
// join ram in db.Ramps on v.vehl_rampid equals ram.ramp_RampID
// where
// cus.Capt_Family == "vehl_state" && v.vehl_Deleted == null && v.vehl_ClearanceCompany == p.pusr_CompanyId
// select new qryRslt
// {
// vehl_ContainerNo = v.vehl_ContainerNo,
// vehl_Name = v.vehl_Name,
// vehl_drivername=v.vehl_drivername,
// vehl_entrancedate=v.vehl_entrancedate,
// vehl_customsdec=v.vehl_customsdec,
// VehicleState=v.vehl_state,
// cont_rampid=v.vehl_rampid==null?" ":ram.ramp_Name
// }).ToList();
it gives me an unexpected result that differs from native sql statement written in sql server
How can I implement sql statement with another sql in case statement?

It depends what you returning. Let's assume you are trying to return class: MyClass
Then LINQ would looks something like:
List<MyClass> result = (from c in Vehicle
from x in Custom_Captions
join z in Ramp on c.vehl_rampId equals z.ramp_RampID
where c.vehl_state == x.Capt_Code
&& x.Capt_Family == 'vehl_state'
&& c.vehl_ClearanceCompany == 471
select new MyClass{
prop1 = c.vehl_rampid is null ? "" : z.ramp_Name
}).ToList();
Above code is using Object Initialiser to define object by filling it's all properties.

linq convert query syntax to method syntax [closed]

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How can I convert this query syntax to method syntax in linq:
return (from x in db.Table1
join y in db.Table1 on x.ID equals y.ID - 1
where Convert.ToInt32(y.ID) >= Convert.ToInt32(x.ID)
orderby x.Name
select x).Distinct();
Which approach is better? I like this query approach better but I was asked to work with method syntax which looks too bloated to me.

var results = db.Table1.Join
(
db.Table1,
x=>x.ID,
x=>x.ID - 1,
(x,y)=>new{OuterTable = x, xid = x.ID, yid = y.ID}
)
.Where(x=>Convert.ToInt32(x.yid ) >= Convert.ToInt32(x.xid))
.Select(x=>x.OuterTable)
.OrderBy(x=>x.Name)
.Distinct();