All Questions
11 questions
0
votes
2
answers
90
views
IQueryable Lambda Expression for every Nth date
I have a calendar table that contains a series of dates, and I'm trying to write a query that gives me every N dates. I can do this in SQL without difficulty, but when writing it in a IQueryable with ...
0
votes
0
answers
264
views
How to apply an expression to an IQueryable for Entity Framework?
I've got a dictionary of lambda expressions:
private readonly Dictionary<SortSpec, Func<IQueryable<CompanyData>, IQueryable<CompanyData>>> _sortHelp =
new Dictionary<...
- 1,805
1
vote
2
answers
348
views
How do I abstract out the select in this Entity Framework IQueryable query?
I have the following Entity Framework queries:
var items1 = items.Select(x=> x.Prop1)
.Select(...).OrderBy(..).ToArray();
var items2 = items.Select(x=> x.Prop2)
...
- 886
0
votes
1
answer
36
views
Finding the appropriate return type for linq to SQL generic functions
I'm trying to build an extension method to IQueryable which accepts a sort direction as an argument. I want to be able to apply this method to SQL server queries with EF. Here is what I have so far:
...
- 2,626
1
vote
3
answers
67
views
Building query to filter on OR conditions
I'm trying to build a query where I filter news based on themes. Every news item can have several themes. When I filter I want to get every news item that has any of the themes I filter with but what ...
0
votes
1
answer
1k
views
Execute IQueryable after it's being done building
I want to build filters on IQueryable depending on user input and execute the query only at the end. I'm trying to understand concept behind and if this is going to work as expected.
Will the query ...
- 4,511
0
votes
2
answers
175
views
Strange lambda Expression breaks down IIS
I do a query with an IQueryable<T> on an Entity.DbSet. When I insert this line of code:
query =
query.Where(x => x.VersionInt == query.Max(y => y.VersionInt))
The whole IIS breaks ...
user887983
0
votes
0
answers
803
views
Why is it that Entity Framework gives the error "Enumeration yielded no results" for typical many-to-many functionality?
Our ASP.NET C# web application is used in the following environment .NET Framework 4
ASP.NET Web Forms.
IIS 7
Windows 2008
Visual Studio 2010
.NET IDE C#
HTTPS ( SSL )
-Entity Framework 5
In ...
- 1,469
2
votes
3
answers
9k
views
Composing Expression<Func<T, bool>> predicates
I have a method that returns an
Expression<Func<T, bool>>
When I use this as a predicate in a where clause in EF this works fine, until I try to add more items to the predicate with ...
- 1,392
0
votes
1
answer
408
views
SelectMany on an IQueryable ignores conditions?
I'm trying to use SelectMany to evaluate a first query with conditions, based on those results execute another query. I've been told that SelectMany should be able to do this. The problem I'm having ...
- 4,484
2
votes
0
answers
1k
views
How to create filter expression dynamically in EF IQueryable?
Lets say we have interface:
public interface ISystemCompany
{
Guid SystemCompanyId { get; set; }
}
We also have IQueryable<> of type, that implements ISystemCompany.
We have specific ...
- 31.8k