👀 Views: 83 💬 Answers: 1 📅 Created: 2025-06-27

core-data ios swift

I'm stuck on something that should probably be simple... I'm testing a new approach and I'm working with an scenario when fetching data from Core Data on my iPhone 13 simulator. I have a simple model with an entity called `User` that has `name` and `age` attributes. The fetch request I constructed is supposed to return all users over the age of 18, but it's returning an empty array even when I know there are users who meet this criterion. Here's the fetch request I'm using: ```swift let fetchRequest: NSFetchRequest<User> = User.fetchRequest() fetchRequest.predicate = NSPredicate(format: "age > %d", 18) ``` I also ensured that I have persisted some test data. I confirmed that a few `User` entities have ages greater than 18 by manually checking the persistent store. However, when I execute the fetch request with: ```swift let users = try context.fetch(fetchRequest) ``` ...the `users` array is always empty. I tried running the fetch request on both the simulator and a physical device with iOS 16.1 but got the same result. I've also verified that the context is saved properly after inserting users using: ```swift if context.hasChanges { try context.save() } ``` I suspect there might be an scenario with the context or the way I'm setting up the fetch request. Are there any common pitfalls I might be overlooking, or additional debugging steps I could take to understand why the fetch is not returning the expected results? Any insights would be greatly appreciated! This is happening in both development and production on Debian. Any feedback is welcome! I'm using Swift 3.10 in this project. Any ideas how to fix this?