I’m using NSPersistentCloudKitContainer and I’m utilising the public database and also the user’s private database. For example I have an entity called Category which has a many-to-many relationship to an entity called NewsArticle. So the NewsArticles exist in the public database for the user to browse, but he can add them to a category which will live in his private database. So that’s my question, is it possible for an entity which exists a in the private database to have a relationship to another entity in a public database?

Hi, We are having problems with IOs Quick Look not working. Specifically, the AR button being greyed out after having opened the Scene / AR model previously. This is all running off our Web-App. What we have figured out is clearing the device's cache solves the issue and the greyed out button turns blue and clickable again. We are receiving this issue very inconsistently though - on iPad as well as iPhone and on both newer and older IOs versions. Very happy for any responses and advice to solve this issue as its behaviour makes the quick look function - even if it's great (when it works) unviable for Production (because it doesn't work consistently). Best Regards

How can we identify whether the remote change notification is triggered because some data was changed on a different device and it is downloaded from CloudKit, or it is triggered from the current device because new entity was saved into database. Because this notification is posted when both remote data is downloaded or local data is created. It would be great if there is a way to understand the origin of the notification.

I am using a Mac Catalyst app and saving the content of the app in core data. After uninstalling the app the saved core data file is not getting deleted. Due to this I am having major bugs during launch of the app. My requirement is core data contents should be removed once the app is uninstalled. Anybody with solutions for this?

CoreData: Zone metadata is missing it's encoded share data but is marked for a mutation: <CKRecordZoneID: 0x600003f044e0; zoneName=com.apple.coredata.cloudkit.share.30BE5FAE-3FE0-4142-90C4-E78FFA90B2A2, ownerName=defaultOwner> - <decode: bad range for [%@] got [offs:312 len:1242 within:0]>

I have a CoreData model, in a Swift Package with tests. I can successfully run the tests, when I load the model using NSPersistentContainer, however attempting this with NSPersistentCloudKitContainer always fails in the call to loadPersistentStores(completionHandler block: @escaping (NSPersistentStoreDescription, Error?) -> Void) The error is : [CK] BUG IN CLIENT OF CLOUDKIT: Not entitled to listen to push notifications. Please add the 'aps-connection-initiate' entitlement. This issue is described on StackOverflow however, the accepted solution does not appear to work in my case. I have tried adding the aps-connection-initiate key to my App Info.plist, the Test Info.plist and the SPM bundle. No change. (NB. adding this to the entitlements file just breaks auto signing). I have enabled App entitlements for App Groups, Remote Notifications background mode, Push Notifications and iCloud CloudKit with a store identifier. I have checked my model. All relationships have inverses. No unique constraints, etc. etc. I am sharing a Bundle ID with a previous version of the App, that also uses CoreData+CloudKit, each version has it's own Model and container identifier, each container identifier is available in the provisioning profile. The new version of the model has two NSPersistentStoreDescriptions, one is configured for CloudKit, the other is a local cache. I am completely stuck, suggestions would be very welcome.

Hello, I have class file, which should save data coreData and Im only able to save data via ui. Do you have any example, how can I save data in core data via class files? Greeting Fabian

I am currently writing an app that is about writing stories. As of now, it is fairly simple: ContentView is your "Collection" of stories. PopupView is when you click on a button in ContentView. In popup view you enter the story title. Once you do that, you are brought to a blank page which is StoryView, where the NavigationTitle is what your story title is. Once I finish the story and leave the page / StoryView, it is still there, but once I close the app on my phone and reopen it, the story is gone and is not saved. I am a relatively new developer, so ive been relying on ChatGPT and Google Gemini for the saving parts of this, but it rarely works, and the furthest ive gotten with it is that it saves the story title but doesn't save the content of the story. I have a feeling that the AI is overdoing it as well. If anyone could help, please do so. Ive been trying to fix this for days. If you need me to provide any code, I am happy to do so. [Edited by Moderator]

Hello. I recently released a new version (2.6) of my CloudKit syncing CoreData based app. The new version uses v18 of my data model. V18 is exactly like v17, except for a new optional string field in one of the entities. I diffed the two model versions to be extra sure. During my test I did not encounter any crash, and I also tested automatic migration, installing 2.55 and building 2.6 on top of it. No troubles. However my crash logger reports a number of crashes among my users. It's not a huge numbers (10 users over about 900 or more) but I am surprised it crashes at all. The crash happens when I call NSPersistentCloudKitContainer.loadPersistentStores, I get this error in the completion block: The model used to open the store is incompatible with the one used to create the store" I always assumed these slight changes (new field added to an existing model) did not require a manual migration. Any suggestions?

I am trying to profile my app for 'Data Persistence', but I am not getting any data in the Instruments. I tried restarting Xcode and Mac, still no progress. It is showing blank graph for faults, fetches and saves

We currently have a shoebox-based architecture but want to transition to a document-based architecture, so UIManagedDocument seems like an obvious choice. However, the UIManagedDocument API seems outdated given the relatively newer NSPersistentContainer API. Also, it’s not clear if UIManagedDocument’s managedObjectContext can be used on the main thread or not. Ideally, I would like to see a persistentContainer property added to UIManagedDocument which could then be used to obtain the view context or a background managed object context. Does anyone have any suggestions on the latest best practices for document-based architectures using CoreData? I’m more interested in Swift implementations, but knowing best practices for SwiftUI and SwiftData would be helpful too.

Hi all In pursuit of adopting widgets in my application, I have transitioned from AppSupport to AppGroup as storage location for Core Data. I have done a migration process/flow that goes as follows and which have been tested multiple times although I have yet to publish the update: Check if migration has taken place or not 1a. if yes continue to app 1b. If no continue flow Begin migration process 2a. Backup original store in AppSupport 2b. Migrate store to AppGroup 2c. Migrate userdefaults to AppGroup 2d. Update userdefaults with true for both hasMigratedToAppGroup and hasMigratedUserDefaultsToAppGroup Is there any tips or stuff to look for that hasn’t been taken in to account? How have you done it previously, and what would be recommended? Also, is there some specific tests to run/over many times get a baseline of how many is succeeding or failing? Thanks in advance.

persist images even after the app is uninstalled, if we reinstall the app can we display same images in app? but our app not use any cloud or server. Thanks in advance.

I am building an app that manages ScreenTime and I would like to persist the tokens of which apps are frequently limited to CoreData locally. I attempted to do so by converting to a string but was unable to find a way to initialize an ActivityCategoryToken with a string. Is this possible? Am I going about it the wrong way? Thanks.

What sets the SwiftData framework apart from traditional iOS data storage solutions like Core Data or Realm? Could you elaborate on SwiftData's unique features and architecture that enable developers to efficiently manage data in their Swift projects? How does SwiftData enhance the development experience by seamlessly integrating with Swift's language features and paradigms

I recently discovered the new documentation for enabling CloudKit sync with SwiftData. A key step I was missing in my previous setup was this step: Initialize the CloudKit development schema. When I run this though, I get Core Data errors in my log... CoreData: Unsupported attribute type I've noticed that it seems to be preventing adding fields for my model properties that are Codable structs. I've been able to add Codable structs to my SwiftData models synced with CloudKit before. But using Core Data to initialize the CloudKit schema like the documentation suggests just doesn't work. Is there some other way around this? I'm about to just give up on CloudKit sync altogether. I need this to work because I'm trying to add some new fields and populate the fields with data based on existing data during the migration, but this seems to be preventing migration completely. If I don't initialize the schema, I get different errors and the ModelContainer won't initialize at all.

Some of my users are reporting an inability to sync via CloudKit between devices. I have not seen it on any of my devices, but one user got me some console logs that are showing the following error: <CKError 0x600000a0f840: "Partial Failure" (2/1011); "Failed to modify some records"; uuid = EDC7B3E3-02F8-43B7-83B6-22D17EF0442A; container ID = "iCloud.cribaudo.iphemeris"; partial errors: { C611E11F-3DC0-484C-8FC1-23473062D9D0:(com.apple.coredata.cloudkit.zone:defaultOwner) = <CKError 0x600000a04660: "Invalid Arguments" (12/2006); server message = "Cannot create or modify field 'CD_nameFirstChar' in record 'CD_Charts' in production schema"; op = D83EF1F7DD772042; uuid = EDC7B3E3-02F8-43B7-83B6-22D17EF0442A> I do not understand this: The field CD_nameFirstChar was added to the data model in the version 15. Automatic Migration is enabled. The CloudKit Console says the Private Database Container being used by my App is deployed to production. The entity CD_Charts (I only have one) that is deployed to production shows that field as present (CD_nameFirstChar). Why would this user be getting this error? As far as I can see they are running a version where migration to Model 15 should have been triggered at some point in the past. If somehow something went wrong with their migration, how would I fix it? Any thoughts / ideas are appreciated. One thing I should add is that the migration from Model 14 to 15 was not lightweight. I did use: @interface ModelMigration14to15 : NSEntityMigrationPolicy -(NSString *)nameFirstChar:(NSString *)name; @end And I used a MapModel14to15 which used the above function to set the value of nameFirstChar. The Value Expression for that attribute is: FUNCTION($entityPolicy,` "nameFirstChar:" , $source.name) from the above mentioned NSEntityMigrationPolicy class. This worked ok on all my devices and apparently on some user devices. This issues seems to effect only a small subset of my users but not all? So I am at a loss to understand why this would happen or how to fix it.

Porting some Core Data code that was written several years ago. It has an entity called Transaction. This pre-dates Transaction that appeared in Animation. So Apple is now colliding with my naming. Looks like light weight migration isn't going to do the trick and I need to do more work for migration to work. Checking whether there is some magical use of namespace where I could separate my entity use of Transaction. Or it's full weight migration...

Hi, I thought this should be quite easy and maybe I only have tomatoes on my eyes, but I cannot find out how to call an action when the user clicks the red button or use CMD-W to close the Preferences window (= Settings Scene). I use Core Data. In the Preferences, many data structures, which define my system, are changed. I learned, that you shouldn't save too often to avoid performance problems, so now I want to save the Core Data context when the user closes the Preferences window. I tried .onDisappear, onChange of focus etc. but this didn't work. How can I define an action? Any hints are welcome :-)

Hello I have a TestFlight tester getting a random repeated crash when the app is interacting with core data. Every time it crashes we get the call stack like below from line 6 stating -NSManagedObject _processRecentChanges. Searching for _sharedIMPL_setvfk_core it seems to indicate a multithreading issue but my managedObjectContext is initialized with main queue concurrency. - (NSManagedObjectContext *)managedObjectContext { if (managedObjectContext != nil) { return managedObjectContext; } NSPersistentStoreCoordinator *coordinator = [self persistentStoreCoordinator]; if (coordinator != nil) { managedObjectContext = [[NSManagedObjectContext alloc] initWithConcurrencyType: NSMainQueueConcurrencyType]; [managedObjectContext setPersistentStoreCoordinator:coordinator]; } return managedObjectContext; } When I pulled the cashpoint in to the Xcode project everything appears to be running on the main thread. I can't seem to find documentation on what might be causing the issue. Any pointers would be appreciated. The app is compiled on Xcode 15 targeting iOS 15. Users device is iOS 17.3.1.