EF Core: How can i Select (Distinct) after join?

How to select Distinct / Group By child property in both LINQ method and syntax?

There's no reason to join to the parent, because you can just use ...Child.ParentId...Anyway, you can do this:...var result = db.Set<Child>().Where(c => c.Parent.ParentId = 1).GroupBy(c => c.Grade); ...Or without the join;...var result = db.Set<Child>().Where(c => c.ParentId = 1).GroupBy(c => c.Grade); ...And distinct is simply:...var result = db.S...

EF Core Left Join and then Inner Join

As @Daniel García Rubio noted, it is hard to answer your question with the small amount of information you provided in your question. Without knowing more though, it would seem like you are looking for the following:...List<TableBid> bid = _context.TableBid .Include(bid => bic.Product.TableStock) .ThenInclude(stock => stock...

Linq select distinct count performed in memory

The query is executing in memory because you instantiating a collection of BookListViewModel objects with the statement ....Select(i => new BookListViewModel {...}) ...If you simply remove the class BookListViewModel, Linq will execute the perform the query on the db side (which is a good idea since the optimizer is much more efficient)...

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

var rowsToReturn = await _context.Records .Where(b => b.SId == bId) .Select(d => d.Date) .Distinct() .OrderBy(d => d) .AsEnumerable() .ToListAsync(); return rowsToReturn; ...Use AsEnumerable() before ToListAsync(). It will work.

How to implement a left join with some condition on second table in EF / EF Core?

Something like:...var filteredCenterCodeSends = dbContext.HISBaseCenterCodeSends .Include( ccs => ccs.Insur ) // assuming navigation property name .Where( ccs => ccs.Center.CenterCode == 2 && ccs.ServiceGroup.ID == 4 ); // if ccs.Insur/ID is nullable, also add `&& ccs.Insur != null` var insurersWithFilteredCcs = d...

INNER Join and LEFT OUTER JOIN in EF-Core with Linq

Below you can find a simplified version of your example, using a single ...DbContext...:...var batchId = 123; var transactionDetailFailureReasonsToExcludeQuery = from r in dbContext.TransactionDetailFailureReasons where r.TransactionFailureReasonID == "NRD" || r.TransactionFailureReasonID == "RDP" || r.TransactionFa...

What is the difference between EF Core Database-First and EF Core Code-First approaches?

Database-First...DB-First is that you reverse engineer an existing database to create an Entity Framework model.Instead of designing the EDMX manually and generating the SQL script to create the Database, we build the latter and then generate the former using the Entity Framework Designer tool....Code-First...Code-First uses migrations to create th...

Migrating from EF Core 2 to EF Core 3

Answer to your question is going to be really verbose because it's corresponds to some different changes happened in EF Core 3.0; So, let's just consider a little part of it....As you've mentioned in your question, microsoft has a somehow confusing description about the changes on version 3.0 in ...this post.......The first part of the above post i...

EF Core Navigation Property Include uses Left Join instead of Inner Join

Relational databases cannot enforce one-to-one (i.e. both ends required) relationship, because no standard FK constraint can prevent deleting the dependent record (...TeamSettings... in your case). ...Hence EF Core does not support it (...[Required]... attribute on ...[Team.TeamSettings]... is ignored). This is sort of explained in the ...Required ...

Selecting mutiple rows for each distinct value in column EF Core in C#

Language: C#...For simplicitys sake lets say I have a DbSet containing products and the Product class looks like this:...public class Product { public DateTime Time { get; set; } public string Category { get; set; } } ...Time is a record of when the product was added to the database....I have a list of strings with all categories that exist...