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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)
);
}
}

EntityFremework: could a select before a where optimize this?

I'm trying to gain performance on this query, and I'd like to know if calling a Select() before the Where() I could have some improvement:
public async Task<List<PostValues>> GetValuesToTheDashboard(DataFilter filter, CancellationToken cancellationToken) {
long startTimestanp = Helpers.UnixTimeNow(filter.StartDate);
long endTimestanp = Helpers.UnixTimeNow(filter.EndDate);
return await
_context.CatchDetails.Where(
x => x.Monitoring.Client.Id == filter.CustomerId && x.Data.published >= startTimestanp
&& x.Data.published <= endTimestanp
&& ((filter.Sentiment == Sentiments.ALL) || x.Sentiment_enum == filter.Sentiment)
&& (filter.MonitoringId == 0 || x.Monitoring.id == filter.MonitoringId)
&& (filter.KeywordId == 0 || x.Keyword.Id == filter.KeywordId)
&& (filter.MotiveId == 0 || x.Motive.Id == filter.MotiveId)
&& (filter.SocialNetwork.Count == 0 || filter.SocialNetwork.Any(s => x.Data.social_media == s))
&& (filter.Busca == "" || x.Data.content_snippet.Contains(filter.Busca))
&& (filter.Gender.Count == 0 || filter.Gender.Any(g => x.Data.extra_author_attributes.gender_enum == g)))
.Select(s => new PostValues() {
CatchDetailsId=s.Id,
Monitoring=s.Monitoring.name,
Keyword=s.Keyword.Text,
Motive=s.Motive.Name,
Sentiment=s.Sentiment_enum,
Gender=s.Data.extra_author_attributes.gender_enum,
SocialMedia=s.Data.social_media,
Country=s.Data.extra_author_attributes.world_data.country_code,
State=s.Data.extra_author_attributes.world_data.region,
Published=s.Data.published
}).ToListAsync(cancellationToken);
}

There might be a way how to improve performance, but it won't be with switching Select and Where (as Chetan mentioned in the comment).
You could build the query in a sequence and based on the filter get a simpler query in the end. This would go like this:
var query = _context.CatchDetails.Where(
x => x.Monitoring.Client.Id == filter.CustomerId && x.Data.published >= startTimestanp
&& x.Data.published <= endTimestanp);
if (filter.Sentiment != Sentiments.ALL)
{
query = query.Where(x => x.Sentiment_enum == filter.Sentiment);
}
if (filter.MonitoringId != 0)
{
query = query.Where(x => x.Monitoring.id == filter.MonitoringId);
}
[...]
return await
query.Select(s => new PostValues() {
[...]
}).ToListAsync(cancellationToken);

Do not forget, the variable query is already on memory of the application when the SQL returns data. If there is many results it could throw memory exception.
I suggest that you limit the range of date on that search.

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 };

Merge two Ordering Results into one result in linq with 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)

Nullable Parameter used in Lambda Query is being ignored

I'm trying to pass a null value from a RenderAction to another view. But in between, at the controller, my linq lambda expression is not loading the right field, despite the null value going through correctly..
SprintManager.cshtml
<div id="Global_Backlog_Board" class="Board_Panel">
#{Html.RenderAction("ListOfSingleCards", new
{
State_ID = 1
});}
</div>
HomeController.cs
public PartialViewResult ListOfSingleCards( int? Sprint_ID,
int State_ID = 1)
{
var Cards = db.Cards.Where(x => x.State_ID == State_ID &&
x.Sprint_ID == Sprint_ID &&
x.Deleted != 1 &&
x.Archive != 1).ToList();
return PartialView(Cards);
}
So Sprint_ID is being passed over and loaded as null here, but I can't get the query to load the rows correctly.
In fact, the following works:
var Cards = db.Cards.Where(x => x.State_ID == State_ID &&
x.Sprint_ID == null &&
x.Deleted != 1 &&
x.Archive != 1).ToList();
So I suppose I could check if Sprint_ID is null and depending on the result run one of the two seperate queries, but I'd like to understand why my original attempt is not working.
Thank you!

I don't know the correct answer but based on your solution you should be able to tidy it up:
var cards = new List<Card>();
var query = db.Cards.Where(x => x.State_ID == State_ID &&
x.Deleted != 1 &&
x.Archive != 1);
if (Sprint_ID.HasValue)
query = query.Where(x => x.Sprint_ID == Sprint_ID);
else
query = query.Where(x => x.Sprint_ID == null);
cards = query.ToList();

A nullable int won't return "null" in the way that you're thinking. You have to check the HasValue property of it to determine if there is a value, and if so then use it otherwise use null:
public PartialViewResult ListOfSingleCards( int? Sprint_ID,
int State_ID = 1)
{
var Cards = db.Cards.Where(x => x.State_ID == State_ID &&
x.Sprint_ID == Sprint_ID.HasValue ? Sprint_ID.Value : null &&
x.Deleted != 1 &&
x.Archive != 1).ToList();
return PartialView(Cards);
}

Until something better comes a long, I'm using this:
var Cards = new List<Card>();
if (Sprint_ID == null)
{
Cards = db.Cards.Where(x => x.State_ID == State_ID &&
x.Sprint_ID == null &&
x.Deleted != 1 &&
x.Archive != 1).ToList();
}
else
{
Cards = db.Cards.Where(x => x.State_ID == State_ID &&
x.Sprint_ID == Sprint_ID &&
x.Deleted != 1 &&
x.Archive != 1).ToList();
}