Merge two Ordering Results into one result in linq with C# - c#

I order two types of query. I want to show the result as one. if the first query and second query have count these both are merge and show the results of one. So i have created 3 list like jobs, jobs1, jobs2. I am getting values into jobs1 and jobs2. Then i have assigned using union into jobs3
Code
IQueryable<Job> jobs = _repository.GetJobs();
IQueryable<Job> jobs1 = _repository.GetJobs();
IQueryable<Job> jobs2 = _repository.GetJobs();
List<int> lstId = null;
List<int> lstUpdatedListId = null;
List<int> lstConId=null;
var order = _db.GetOrderDetails().Where(od => od.Masters.Id != null && od.OrderId == od.Master.OrderId && od.Master.Status == true && od.ValidityTill.Value >= currentdate).OrderByDescending(od => od.ValidityTill).Select(ord => ord.Master.Id.Value);
var order1 = _vasRepository.GetOrderDetails().Where(od => od.Masters.ConId != null && od.OrderId == od.Masters.OrderId && od.Masters.PaymentStatus == true && od.ValidityTill.Value >= currentdate).OrderByDescending(od => od.ValidityTill).Select(ord => ord.Masters.ConId.Value);
var updatedVacancyList = _repository.GetJobs().Where(c => c.UpdatedDate != null && updateFresh <= c.UpdatedDate).Select(c => c.Id);
if (order1 .Count() > 0)
{
lstConId = order1.ToList();
Func<IQueryable<Job>, IOrderedQueryable<Job>> orderingFunc = query =>
{
if (order1.Count() > 0)
return query.OrderByDescending(rslt => lstConId.Contains(rslt.Con.Id)).ThenByDescending(rslt=>rslt.CreatedDate);
else
return query.OrderByDescending(rslt => rslt.CreatedDate);
};
jobs1 = orderingFunc(jobs);
}
if (order.Count() > 0)
{
lstId = order.ToList();
lstUpdatedJobsListId = updatedVacancyList.ToList();
Func<IQueryable<Job>, IOrderedQueryable<Job>> orderingFunc = query =>
{
if (order.Count() > 0)
return query.OrderByDescending(rslt => lstId.Contains(rslt.Id)).ThenByDescending(rslt => lstUpdatedJobsListId.Contains(rslt.Id)).ThenByDescending(rslt=>rslt.CreatedDate);
if (updatedVacancyList.Count() > 0)
return query.OrderByDescending(rslt => lstUpdatedJobsListId.Contains(rslt.Id)).ThenByDescending(rslt => rslt.UpdatedDate);
else
return query.OrderByDescending(rslt => rslt.CreatedDate);
};
jobs2 = orderingFunc(jobs);
}
jobs = jobs1.Union(jobs2);
and i am getting an error while run the application as follows,
The text data type cannot be selected as DISTINCT because it is not comparable.
I need help to rectify this issue. I want to order in descending also.

One of your columns in Database is "Text" type. Convert it to varchar(MAX)

Related

C# Entity Framework how to dynamically add 'And' , 'or' condition to the query

I have following method which applies AND condition. But I would like to have OR condition based on parameter in filter.
public async Task<IList<PerformanceReportUser>> GetUsersForPerformanceReport(PerformanceReportFilter filter)
{
var query = _context.Set<EntityUser>()
.AsNoTracking()
.AsQueryable();
if(filter != null)
{
if (filter.Modified.HasValue)
{
query = query.Where(q => q.Modified >= filter.Modified);
}
// How can I have dynamically the OR condition based on filter parameter?
if (filter.Created.HasValue)
{
query = query.Where(q => q.Created >= filter.Created);
}
}
var result = query.Select(user => ToDomain(user));
return await result.ToListAsync();
}
Basically in SQL, I am expecting something like below.
If parameter is 'Or':
Select *
From EntityUser
Where Created >= '2021-01-01' Or Modified >= '2022-02-02'
If parameter is 'And'
Select *
From EntityUser
Where Created >= '2021-01-01' And Modified >= '2022-02-02'
If you want OR inside this types of querys, you have to do in same line, something similar to this:
var query = _context.Set<EntityUser>()
.AsNoTracking()
.AsQueryable();
if(filter != null)
{
query = query.Where(q =>
(filter.Modified.HasValue && q.Modified >= filter.Modified)
||
(filter.Created.HasValue && q.Created >= filter.Created)
);
}
EDITED
If you want dinamicaly condition based on filter use something similar to this...
var query = _context.Set<EntityUser>()
.AsNoTracking()
.AsQueryable();
if(filter != null)
{
if(filter.condition == "OR"){
query = query.Where(q =>
(filter.Modified.HasValue && q.Modified >= filter.Modified)
||
(filter.Created.HasValue && q.Created >= filter.Created)
);
}else{
query = query.Where(q =>
(filter.Modified.HasValue && q.Modified >= filter.Modified)
&&
(filter.Created.HasValue && q.Created >= filter.Created)
);
}
}

Difference between LINQ Lambda and SQL statement

I have the following lambda statement:
var resources = Db.Resource.Where(w => w.ResValue.Any(a => a.ApplicationFk == applicationPk) && w.CategoryFk == (categoryId ?? w.CategoryFk ) && w.IsEditable);
if (cultureIdsMissing!= null)
{
resources = resources.Where(w => w.ResValue.Any(a => cultureIdsMissing.Any(aa => aa == a.CultureFk) && a.Value == string.Empty));
}
This is not returning the result which I want, which is returned by:
SELECT Resource.ResourcePk, Resource.CategoryFk, Resource.Name, Resource.IsEditable, ResValue.ApplicatieFk, ResValue.CultureFk, ResValue.Value
FROM Resource
INNER JOIN ResValue ON Resource.ResourcePk = ResValue.ResourceFk
WHERE (ResValue.ApplicatieFk = 6)
AND (Resource.IsEditable = 1)
AND (ResValue.Value = '')
AND (ResValue.CultureFk = 1 OR ResValue.CultureFk = 2)
Not that cultureIdsMissing is a List containing both the numbers 1 and 2.
What am I missing or doing wrong with the lambda query?
I think you have to remove && w.CategoryFk == (categoryId ?? w.CategoryFk ) from your linq lemda expression. if categoryId = 1 then it will take only records with value 1. So try after remove that. Your linq code should be this.
var resources = Db.Resource.Where(w => w.ResValue.Any(a => a.ApplicationFk == applicationPk)&& w.IsEditable);
if (cultureIdsMissing!= null)
{
resources = resources.Where(w => w.ResValue.Any(a => cultureIdsMissing.Any(aa => aa == a.CultureFk) && a.Value == string.Empty));
}
You should take it from your sql statement :
Db.Resource
.Join(Db.ResValue
, rs => rs.ResourcePk
, resV => resv.resourceFk
, (rs, resv) => new { res = rs, resV = resV })
.Where(w => w.resv.ApplicatieFk == 6
&& w.res ==1
&& resv.Value == string.empty()
&& (resv.CultureFk == 1 || resv.CultureFk == 2))
It's not tested so maybe it won't work on first try.
I would translate the SQL to query comprehension syntax. In general, convert phrases in query comprehension order, use table aliases as range variables (or create range variables), and put unary/overall aggregate functions (such as TOP, DISTINCT or SUM) as function calls outside the whole query. For your SQL,
var ans = from r in Resource
where r.IsEditable == 1
join rv in ResValue on r.ResourcePk equals rv.ResourceFk
where rv.ApplicatieFk == 6 && rv.Value == "" && (rv.CultureFk == 1 || rv.CultureFk == 2)
select new { r.ResourcePk, r.CategoryFk, r.Name, r.IsEditable, rv.ApplicatieFk, rv.CultureFk, rv.Value };

How to combine the multiple part linq into one query?

Operator should be ‘AND’ and not a ‘OR’.
I am trying to refactor the following code and i understood the following way of writing linq query may not be the correct way. Can somone advice me how to combine the following into one query.
AllCompany.Where(itm => itm != null).Distinct().ToList();
if (AllCompany.Count > 0)
{
//COMPANY NAME
if (isfldCompanyName)
{
AllCompany = AllCompany.Where(company => company["Company Name"].StartsWith(fldCompanyName)).ToList();
}
//SECTOR
if (isfldSector)
{
AllCompany = AllCompany.Where(company => fldSector.Intersect(company["Sectors"].Split('|')).Any()).ToList();
}
//LOCATION
if (isfldLocation)
{
AllCompany = AllCompany.Where(company => fldLocation.Intersect(company["Location"].Split('|')).Any()).ToList();
}
//CREATED DATE
if (isfldcreatedDate)
{
AllCompany = AllCompany.Where(company => company.Statistics.Created >= createdDate).ToList();
}
//LAST UPDATED DATE
if (isfldUpdatedDate)
{
AllCompany = AllCompany.Where(company => company.Statistics.Updated >= updatedDate).ToList();
}
//Allow Placements
if (isfldEmployerLevel)
{
fldEmployerLevel = (fldEmployerLevel == "Yes") ? "1" : "";
AllCompany = AllCompany.Where(company => company["Allow Placements"].ToString() == fldEmployerLevel).ToList();
}
Firstly, unless AllCompany is of some magic custom type, the first line gives you nothing.
Also I have a doubt that Distinctworks the way You want it to. I don't know the type of AllCompany but I would guess it gives you only reference distinction.
Either way here'w what I think You want:
fldEmployerLevel = (fldEmployerLevel == "Yes") ? "1" : "";
var result = AllCompany.Where(itm => itm != null)
.Where(company => !isfldCompanyName || company["Company Name"].StartsWith(fldCompanyName))
.Where(company => !isfldSector|| fldSector.Intersect(company["Sectors"].Split('|')).Any())
.Where(company => !isfldLocation|| fldLocation.Intersect(company["Location"].Split('|')).Any())
.Where(company => !isfldcreatedDate|| company.Statistics.Created >= createdDate)
.Where(company => !isfldUpdatedDate|| company.Statistics.Updated >= updatedDate)
.Where(company => !isfldEmployerLevel|| company["Allow Placements"].ToString() == fldEmployerLevel)
.Distinct()
.ToList();
Edit:
I moved Distinct to the end of the query to optimize the processing.
How about trying like this;
AllCompany = AllCompany .Where(company => (company => company.Statistics.Created >= createdDate)) && (company.Statistics.Updated >= updatedDate));
If every part of query is optional (like created date, last update date..) then you can build linq query string.
Here's a sneaky trick. If you define the following extension method in its own static class:
public virtual IEnumerable<T> WhereAll(params Expression<Predicate<T> filters)
{
return filters.Aggregate(dbSet, (acc, element) => acc.Where(element));
}
then you can write
var result = AllCompany.WhereAll(itm => itm != null,
company => !isfldCompanyName || company["Company Name"].StartsWith(fldCompanyName),
company => !isfldSectorn || fldSector.Intersect(company["Sectors"].Split('|')).Any(),
company => !isfldLocation || fldLocation.Intersect(company["Location"].Split('|')).Any(),
company => !isfldcreatedDate || company.Statistics.Created >= createdDate,
company => !isfldUpdatedDate || company.Statistics.Updated >= updatedDate,
company => !isfldEmployerLevel || company["Allow Placements"].ToString() == fldEmployerLevel)
.Distinct()
.ToList();

Select two columns from the table via linq

I use the query below to get all columns(20 more) in Entity Framework Linq. Because of out of memory exception, I only want to get two of them. One is "FileName", the other one is "FilePath". How to modify my code?
var query = DBContext.Table1
.Where(c => c.FacilityID == facilityID && c.FilePath != null && c.TimeStationOffHook < oldDate)
.OrderBy(c => c.FilePath)
.Skip(1000)
.Take(1000)
.ToList();
foreach(var t in query)
{
Console.WriteLine(t.FilePath +"\\"+t.FileName);
}
var query = DBContext.Table1.Where(c => c.FacilityID == facilityID && c.FilePath != null && c.TimeStationOffHook < oldDate)
.OrderBy(c => c.FilePath)
.Skip(1000)
.Take(1000)
.Select(c => new { c.FilePath, c.FileName })
.ToList();
foreach(var t in query)
{
Console.WriteLine(t.FilePath +"\\"+t.FileName);
}
You need to use Select.
Just select out two of the columns:
DBContext.Table1.Select(c => new { c.FileName, c.FilePath });
How about something like
using (var entity = new MyModel(ConnectionString))
{
var query = (from myTable in entity.theTable
where myTable.FacilityID == facilityID &&
myTable.FilePath != null &&
myTable.TimeStationOffHook < oldDate
orderby myTable.FilePath
select new
{
myTable,FileName,
myTable.FilePath
}).Skip(1000).Take(1000).ToList();
//do what you want with the query result here
}

Lambda or Linq method to search multiple parameters

I have a List of Of Objects and id like to query the list with multiple parameters to whittle down the results on a search page.
int SecLink = (!string.IsNullOrEmpty(Request.QueryString["Sector"])) ? Convert.ToInt32(Request.QueryString["Sector"]) : 0;
int LocLink = (!string.IsNullOrEmpty(Request.QueryString["Location"])) ? Convert.ToInt32(Request.QueryString["Location"]) : 0;
int IndLink = (!string.IsNullOrEmpty(Request.QueryString["Industry"])) ? Convert.ToInt32(Request.QueryString["Industry"]) : 0;
int VacLink = (!string.IsNullOrEmpty(Request.QueryString["Vacancy"])) ? Convert.ToInt32(Request.QueryString["Vacancy"]) : 0;
string keyword = Request.QueryString["SearchTerm"];
var dx = new DataX();
var lstJobs = dx.GetAllJobs().Where(x => x.SectorLink.Equals(SecLink) && x.LocationLink.Equals(LocLink) && x.IndustryLink.Equals(IndLink) && x.VacancyTypeLink.Equals(VacLink) && x.JobName.Contains(keyword)).ToList();
if (lstJobs.Count > 0)
{
uiRptSearchJobs.DataSource = lstJobs;
uiRptSearchJobs.DataBind();
uiLitSearchResults.Text = string.Format("<h4>Search result found {0} matches</h4>", lstJobs.Count);
}
The search params may be '0' as not selected from the previous page, so the results should reflect his.
This is the querystring im passing:
Default.aspx?section=search&Sector=4&Location=0&Industry=0&Vacancy=0&SearchTerm=
but as you can see they querystring will change with what the user selects from the previous page.
If I understand correctly, you don't want to filter if the value of the parameters is 0? If so, two solutions:
Check if the parameter is equal to 0 in your condition:
var lstJobs = dx.GetAllJobs().Where(x =>
(SecLink == 0 || x.SectorLink.Equals(SecLink))
&& (LocLink == 0 || x.LocationLink.Equals(LocLink))
&& (IndLink == 0 || x.IndustryLink.Equals(IndLink))
&& (VacLink == 0 || x.VacancyTypeLink.Equals(VacLink))
&& x.JobName.Contains(keyword)).ToList();
Linq goodness, dynamically construct your query:
var query = dx.GetAllJobs().Where(x => x.JobName.Contains(keyword));
if (SecLink != 0)
{
query = query.Where(x => x.SectorLink.Equals(SecLink));
}
if (LocLink != 0)
{
query = query.Where(x => x.LocationLink.Equals(LocLink));
}
if (IndLink != 0)
{
query = query.Where(x => x.IndustryLink.Equals(IndLink));
}
if (VacLink != 0)
{
query = query.Where(x => x.VacancyTypeLink.Equals(VacLink));
}
var lstJobs = query.ToList();
One option is to conditionally perform the Where clauses:
If the search terms should be ANDed together:
var lstJobs = dx.GetAllJobs();
if (SecLink > 0)
lstJobs = lstJobs.Where(x => x.SectorLink.Equals(SecLink))
if (LocLink > 0)
lstJobs = lstJobs.Where(x => x.LocationLink.Equals(LocLink))
if (IndLink > 0)
lstJobs = lstJobs.Where(x => x.IndustryLink.Equals(IndLink))
if (VacLink > 0)
lstJobs = lstJobs.Where(x => x.VacationLink.Equals(VacLink))
// Performance does not suffer because the query will
// not get evaluated until it's required. For example,
// here we call .ToList, which forces the query to be evaluated.
var result = lstJobs.ToList();
However, you've made it clear you need the search terms ORed together. In that case:
var lstJobs = dx.GetAllJobs().Where(x => x.JobName.Contains(keyword));
if (SecLink > 0)
lstJobs = lstJobs.Union(
dx.GetAllJobs().Where(x => x.SectorLink.Equals(SecLink))
if (LocLink > 0)
lstJobs = lstJobs.Union(
dx.GetAllJobs().Where(x => x.LocationLink.Equals(LocLink))
etc...

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