👀 Views: 308 💬 Answers: 1 📅 Created: 2025-08-28

entity-framework linq c# C#

I've been researching this but I'm deploying to production and I'm working on a project and hit a roadblock... I'm running into an `InvalidOperationException` when trying to query related entities using Entity Framework Core (version 5.0.0). The specific behavior message I'm working with is: `The entity type 'RelatedEntity' want to be tracked because another instance with the same key value is already being tracked.` This happens when I execute a LINQ query to retrieve a parent entity along with its related entities. Here's the code snippet I'm using to retrieve the parent entity and its related entities: ```csharp var parentEntity = await _context.ParentEntities .Include(p => p.RelatedEntities) .FirstOrDefaultAsync(p => p.Id == parentId); ``` I've tried to ensure that I'm not attaching the same context instance multiple times. However, I'm still working with issues especially when I try to filter the related entities based on some conditions: ```csharp var filteredRelatedEntities = parentEntity.RelatedEntities .Where(re => re.SomeProperty == someValue); ``` To troubleshoot, I attempted using `.AsNoTracking()` for the main query: ```csharp var parentEntity = await _context.ParentEntities .AsNoTracking() .Include(p => p.RelatedEntities) .FirstOrDefaultAsync(p => p.Id == parentId); ``` However, this solution didn't resolve the question since I still need to modify the parent entity later in my application logic. Any suggestions on how to handle this situation without running into tracking issues? I’m working with SQL Server as my database provider. Also, I have a similar scenario when trying to nest the queries for different levels of related entities. Any insight would be greatly appreciated! I'm working on a application that needs to handle this. This is my first time working with C# 3.9. I appreciate any insights! Any ideas what could be causing this?