Distinct on with entity framework core

Entity Framework 6 query with Distinct filter

I have a problem. When I run the code below: ...var data = context.TableX.Where(w => w.userId == 9999&& w.id == 9999) .Distinct().ToList(); ...This is the query generated: ...SELECT [Extent1].[id] AS [id], [Extent1].[name] AS [name], [Extent1].[companyId] AS [companyId], [Extent1].[userId] AS [userId] FROM [TableX] AS [Extent1] WHERE (9999 = [Exten...

Deleting parent-child relation with Entity Framework or Entity Framework Core

I'm learning how to use Entity Framework, having a NHibernate background. There are plenty of tutorials on the net, but I didn't find something for my specific case. I don't want to delete the Category record, I only want to delete the relation!...I have following poco's:... public class TrainingCourse { [Key] public int Cour...

Issue when inserting new entity with relationships to existing entities (Entity Framework Core 1.1.0 )

I have encountered an issue when inserting (...Add... method of EF API) or updating (...Update... method of EF API) entities holding reference properties to existing entities (I call existing entity an entity that already exists in the database, and has its PK properly set)....The model consists in ...Place..., ...Person..., ...Address..., and ...S...

Log DbContext.SaveChanges Exception to the database in Entity Framework/Entity Framework Core

In my asp.net core web application, I am logging the exceptions to the database.Till now everything works fine but problem is that when the ...DbConext.SaveChanges... in try block throws an exception, cannot log the exception to the database as ...DbConext.SaveChanges... in ...catch block... also throws the same exception....Here is the code I hav...

Add migration - Both Entity Framework Core and Entity Framework 6 are installed

I have a solution with multiple projects one of them with EF 6 and another one with entityframeworkcore....The migrations were working fine before adding EF6 project, but now I can't use the migration's command : ...add-migration 'anything'...Both Entity Framework Core and Entity Framework 6 are installed. The Entity Framework Core tools are runnin...

Entity Framework Core 2.1 How to OrderBy() and Distinct()

I want to select distinct from my table to get list of years So I wrote the code: ...return await _context.SdrSettingHistory .Where( x => x.StartDate != null) .OrderBy(x => x.StartDate) .Select(x => x.StartDate.Value.Year) .Distinct() .ToListAsync(); ...But it returned...

Selecting all rows based on a distinct column in Entity Framework Core

I have a table with some data which I want to select rows with unique dates using the .NET core entity framework. I want to return the results as a list of the unique rows. Here is the code....public async Task<IEnumerable<Records>> GetUniqueRecordsByDate(int bId) { var rowsToReturn = await _context.Records .Where(b => b.SId ==...

Add or Update child entities when updating a parent entity in Entity Framework Core

In a new project we are using Entity Framework Core instead of EntityFramework 6.2.0. Works good but it causes a problem when updating a parents children while also inserting new children....Example:...Current model:...public class Profile { public Profile() { Interests = new List<Interest>(); } [Key] [DatabaseGenerate...

Get Distinct Entries Based On Specific Column in Entity Framework

I have a SQLite table that contains every test result we've run, and I'm looking to write an entity framework query that returns only the most recent test result per project. ...Normally, I'd assume this would be "group by project id, return row with the max updated value," or, alternatively, "sort by date and return first". However, when I try the...

Entity Framework - Distinct Facets - Performance Optimization

Suppose we have a complex generated query......IQueryable<...> query = ... //something complex ...And then I would like to return multiple "facets" and my current implementation is...... var facets = new { Countries = query.Select(r => new { Id = r.CountryId, Name = r.Country.Name }) .Distinct().ToList(),...