I have not had any successful Schema Migration with CloudKit so far so I'm trying to do with with just very basic attributes, with multiple Versioned Schemas This is the code in my App Main var sharedModelContainer: ModelContainer = { let schema = Schema(versionedSchema: AppSchemaV4.self) do { return try ModelContainer( for: schema, migrationPlan: AppMigrationPlan.self, configurations: ModelConfiguration(cloudKitDatabase: .automatic)) } catch { fatalError("Could not create ModelContainer: \(error)") } }() var body: some Scene { WindowGroup { ItemListView() } .modelContainer(sharedModelContainer) } And this is the code for my MigrationPlan and VersionedSchemas. typealias Item = AppSchemaV4.Item3 enum AppMigrationPlan: SchemaMigrationPlan { static var schemas: [any VersionedSchema.Type] { [AppSchemaV1.self, AppSchemaV2.self, AppSchemaV3.self, AppSchemaV4.self] } static var stages: [MigrationStage] { [migrateV1toV2, migrateV2toV3, migrateV3toV4] } static let migrateV1toV2 = MigrationStage.lightweight( fromVersion: AppSchemaV1.self, toVersion: AppSchemaV2.self ) static let migrateV2toV3 = MigrationStage.lightweight( fromVersion: AppSchemaV2.self, toVersion: AppSchemaV3.self ) static let migrateV3toV4 = MigrationStage.custom( fromVersion: AppSchemaV3.self, toVersion: AppSchemaV4.self, willMigrate: nil, didMigrate: { context in // Fetch all Item1 instances let item1Descriptor = FetchDescriptor<AppSchemaV3.Item1>() let items1 = try context.fetch(item1Descriptor) // Fetch all Item2 instances let item2Descriptor = FetchDescriptor<AppSchemaV3.Item2>() let items2 = try context.fetch(item2Descriptor) // Convert Item1 to Item3 for item in items1 { let newItem = AppSchemaV4.Item3(name: item.name, text: "Migrated from Item1 on \(item.date)") context.insert(newItem) } // Convert Item2 to Item3 for item in items2 { let newItem = AppSchemaV4.Item3(name: item.name, text: "Migrated from Item2 with value \(item.value)") context.insert(newItem) } try? context.save() } ) } enum AppSchemaV1: VersionedSchema { static var versionIdentifier: Schema.Version = Schema.Version(1, 0, 0) static var models: [any PersistentModel.Type] { [Item1.self] } @Model class Item1 { var name: String = "" init(name: String) { self.name = name } } } enum AppSchemaV2: VersionedSchema { static var versionIdentifier: Schema.Version = Schema.Version(2, 0, 0) static var models: [any PersistentModel.Type] { [Item1.self] } @Model class Item1 { var name: String = "" var date: Date = Date() init(name: String) { self.name = name self.date = Date() } } } enum AppSchemaV3: VersionedSchema { static var versionIdentifier: Schema.Version = Schema.Version(3, 0, 0) static var models: [any PersistentModel.Type] { [Item1.self, Item2.self] } @Model class Item1 { var name: String = "" var date: Date = Date() init(name: String) { self.name = name self.date = Date() } } @Model class Item2 { var name: String = "" var value: Int = 0 init(name: String, value: Int) { self.name = name self.value = value } } } enum AppSchemaV4: VersionedSchema { static var versionIdentifier: Schema.Version = Schema.Version(4, 0, 0) static var models: [any PersistentModel.Type] { [Item1.self, Item2.self, Item3.self] } @Model class Item1 { var name: String = "" var date: Date = Date() init(name: String) { self.name = name self.date = Date() } } @Model class Item2 { var name: String = "" var value: Int = 0 init(name: String, value: Int) { self.name = name self.value = value } } @Model class Item3 { var name: String = "" var text: String = "" init(name: String, text: String) { self.name = name self.text = text } } } My experiment was: To create Items for every version of the schema Updating the typealias along the way to reflect the latest Item version. Updating the Schema in my ModelContainer to reflect the latest Schema Version. By AppSchemaV4, I have expected all my Items to be displayed/migrated to Item3, but it does not seem to be the case. I can only see newly created Item3 records. My question is, is there something wrong with how I'm doing the migrations? or are migrations not really working with CloudKit right now?

So i created an App and for some time it was working fine. The app has features to show pdf to users without logging in. I needed to upload all data to cloudkit on public database. I was not having knowledge that there are 2 mode being a noob in coding so after i saved all records in development mode in cloudkit when i published my app, i was not able to see them (Reason because live mode works in Production mode). So i need help now to transfer data from development mode to production mode or any app or code that can help me upload all data in production mode.

I'm implementing SwiftData with inheritance in an app. I have an Entity class with a property name. This class is inherited by two other classes: Store and Person. The Entity model has a one-to-many relationship with a Transaction class. I can list all my Entity models in a List with a @Query annotation without a problem. However, then I try to access the name property of an Entity from a Transaction relationship, the app crashes with the following error: Thread 1: Fatal error: Never access a full future backing data - PersistentIdentifier(id: SwiftData.PersistentIdentifier.ID(backing: SwiftData.PersistentIdentifier.PersistentIdentifierBacking.managedObjectID(0x96530ce28d41eb63 <x-coredata://DABFF7BB-C412-474E-AD50-A1F30AC6DBE9/Person/p4>))) with Optional(F07E7E23-F8F0-4CC0-B282-270B5EDDC7F3) From my attempts to fix the issue, I noticed that: The crash seems related to the relationships with classes that has inherit from another class, since it only happens there. When I create new data, I can usually access it without any problem. The crash mostly happens after reloading the app. This error has been mentioned on the forum (for example here), but in a context not related with inheritance. You can find the full code here. For reference, my models looks like this: @Model class Transaction { @Attribute(.unique) var id: String var name: String var date: Date var amount: Double var entity: Entity? var store: Store? { entity as? Store } var person: Person? { entity as? Person } init( id: String = UUID().uuidString, name: String, amount: Double, date: Date = .now, entity: Entity? = nil, ) { self.id = id self.name = name self.amount = amount self.date = date self.entity = entity } } @Model class Entity: Identifiable { @Attribute(.preserveValueOnDeletion) var name: String var lastUsedAt: Date @Relationship(deleteRule: .cascade, inverse: \Transaction.entity) var operations: [Transaction] init( name: String, lastUsedAt: Date = .now, operations: [Transaction] = [], ) { self.name = name self.lastUsedAt = lastUsedAt self.operations = operations } } @available(iOS 26, *) @Model class Store: Entity { @Attribute(.unique) var id: String var locations: [Location] init( id: String = UUID().uuidString, name: String, lastUsedAt: Date = .now, locations: [Location] = [], operations: [Transaction] = [] ) { self.locations = locations self.id = id super.init(name: name, lastUsedAt: lastUsedAt, operations: operations) } } In order to reproduce the error: Run the app in the simulator. Click the + button to create a new transaction. Relaunch the app, then click on any transaction. The app crashes when it tries to read te name property while building the details view.

Problem Description: When a device (Device 2) stays offline for an extended period after a record is deleted from another synced device (Device 1) via CloudKit, is it possible for Device 2 to miss the deletion notification when it reconnects, even when using CKSyncEngine? This scenario raises questions about whether CKSyncEngine can reliably sync changes if CloudKit archives or purges metadata related to deletions during the offline period. Steps to Reproduce: At time t0: · Device 1 and Device 2 sync successfully via CKSyncEngine (shared record RecordA). Device 2 goes offline. On Device 1: · Delete RecordA; sync completes via CKSyncEngine. Wait for a duration potentially exceeding CloudKit’s change retention window (if such a window exists). Bring Device 2 back online. Observe synchronization: · Expected Behavior: CKSyncEngine removes RecordA from Device 2. · Observed Behavior: RecordA remains on Device 2. Key Questions: Under these conditions, can Device 2 permanently miss the deletion event due to CloudKit’s internal metadata management? Is there a documented retention policy for CloudKit’s change history, and how does CKSyncEngine handle scenarios where this history is truncated? What is the recommended pattern to ensure no events are missed, regardless of offline duration? Clarifications Needed: · If CloudKit does discard deletion metadata after a period, is this considered a framework limitation, or should developers implement additional safeguards? · Does CKSyncEngine log warnings or errors when it detects incomplete sync histories? Environment: · CKSyncEngine with SQLite · CloudKit Private Database · iOS/macOS latest versions Thank you for clarifying how CKSyncEngine is designed to handle this edge case!

Hello, I'm trying to work on an iPadOS and macOS app that will rely on the document-based system to create some kind of orientation task to follow. Let say task1.myfile will be a check point regulation from NYC to SF and task2.myfile will be a visit as many key location as you can in SF. The file represent the specific landmark location and rules of the game. And once open, I will be able to read KML/GPS file to evaluate their score based with the current task. But opened GPS files does not have to be stored in the task file itself, it stay alongside. I wanted to use that scenario to experiment with SwiftData (I'm a long time CoreData user, I even wrote my own WebDAV based persistent store back in the day), and so, mix both on file and in memory persistent store, with distribution based on object class. With CoreData it would have been possible, but I do not see how to achieve that with SwiftData and DocumentGroup integration. Any idea how to do that?

How do I filter data using @Query with a Set of DateComponents? I successfully saved multiple dates using a MultiDatePicker in AddView.swift. In ListView.swift, I want to retrieve all records for the current or today’s date. There are hundreds of examples using @Query with strings and dates, but I haven’t found an example of @Query using a Set of DateComponents Nothing will compile and after hundreds and hundreds of attempts, my hair is turning gray. Please, please, please help me. For example, if the current date is Tuesday, March 4 205, then I want to retrieve both records. Since both records contain Tuesday, March 4, then retrieve both records. Sorting works fine because the order by clause uses period which is a Double. Unfortunately, my syntax is incorrect and I don’t know the correct predicate syntax for @Query and a Set of DateComponents. Class Planner.swift file import SwiftUI import SwiftData 
 @Model class Planner { //var id: UUID = UUID() var grade: Double = 4.0 var kumi: Double = 4.0 var period: Double = 1.0 var dates: Set<DateComponents> = [] init( grade: Double = 4.0, kumi: Double = 4.0, period: Double = 1.0, dates: Set<DateComponents> = [] ) { self.grade = grade self.kumi = kumi self.period = period self.dates = dates 
 } } @Query Model snippet of code does not work The compile error is to use a Set of DateComponents, not just DateComponents. @Query(filter: #Predicate<Planner> { $0.dates = DateComponents(calendar: Calendar.current, year: 2025, month: 3, day: 4)}, sort: [SortDescriptor(\Planner.period)]) var planner: [Planner] ListView.swift image EditView.swift for record #1 DB Browser for SQLlite: record #1 (March 6, 2025 and March 4, 2025) 
 
 [{"isLeapMonth":false,"year":2025,"day":6,"month":3,"calendar":{"identifier":"gregorian","minimumDaysInFirstWeek":1,"current":1,"locale":{"identifier":"en_JP","current":1},"firstWeekday":1,"timeZone":{"identifier":"Asia\/Tokyo"}},"era":1},{"month":3,"year":2025,"day":4,"isLeapMonth":false,"era":1,"calendar":{"locale":{"identifier":"en_JP","current":1},"timeZone":{"identifier":"Asia\/Tokyo"},"current":1,"identifier":"gregorian","firstWeekday":1,"minimumDaysInFirstWeek":1}}]
 EditView.swift for record #2 DB Browser for SQLlite: record #2 (March 3, 2025 and March 4, 2025) 
 [{"calendar":{"minimumDaysInFirstWeek":1,"locale":{"current":1,"identifier":"en_JP"},"timeZone":{"identifier":"Asia\/Tokyo"},"firstWeekday":1,"current":1,"identifier":"gregorian"},"month":3,"day":3,"isLeapMonth":false,"year":2025,"era":1},{"year":2025,"month":3,"era":1,"day":4,"isLeapMonth":false,"calendar":{"identifier":"gregorian","current":1,"firstWeekday":1,"minimumDaysInFirstWeek":1,"timeZone":{"identifier":"Asia\/Tokyo"},"locale":{"current":1,"identifier":"en_JP"}}}]
 
 Any help is greatly appreciated.

Hi, I'm using SwiftData in my app, and I want to sent data to iCloud with CloudKit, but I found that If the user turns off my App iCloud sync function in the settings App, the local data will also be deleted. A better way is maintaining the local data, just don't connect to iCloud.How should I do that? I need guidance!!! I'm just getting started with CloudKit And I would be appreciated!

I'm building a SwiftUI app with SwiftData and want to centralize both query logic and related actions in a manager class. For example, let's say I have a reading app where I need to track the currently reading book across multiple views. What I want to achieve: @Observable class ReadingManager { let modelContext: ModelContext // Ideally, I'd love to do this: @Query(filter: #Predicate<Book> { $0.isCurrentlyReading }) var currentBooks: [Book] // ❌ But @Query doesn't work here var currentBook: Book? { currentBooks.first } func startReading(_ book: Book) { // Stop current book if any if let current = currentBook { current.isCurrentlyReading = false } book.isCurrentlyReading = true try? modelContext.save() } func stopReading() { currentBook?.isCurrentlyReading = false try? modelContext.save() } } // Then use it cleanly in any view: struct BookRow: View { @Environment(ReadingManager.self) var manager let book: Book var body: some View { Text(book.title) Button("Start Reading") { manager.startReading(book) } if manager.currentBook == book { Text("Currently Reading") } } } The problem is @Query only works in SwiftUI views. Without the manager, I'd need to duplicate the same query in every view just to call these common actions. Is there a recommended pattern for this? Or should I just accept query duplication across views as the intended SwiftUI/SwiftData approach?

I am developing an app that uses CloudKit sharing. I recently upgraded my iPad to use 23A5336a. After that upgrade, I can no longer accept a share that is sent to me. I have rebooted the iPad and logged out of the iCloud account and logged back in. Every time I get a share link and tap it, it says: " The owner stopped sharing or your account (xxx) doesn't have permission to open it" This same code, running on the iOS26 device can share with device running iOS18. Is this a known defect? Anything I can do to help resolve this issue?

If Cloudkit is enabled, SwiftData @Query operation hangs when the View scenePhase becomes active. Seems like the more @Query calls you have, the more it hangs. This has been first documented some time ago, but in typical Apple style, it has not been addressed or even commented on. https://developer.apple.com/forums/thread/761434

I have some code which handles doing some computation on a background thread before updating Core Data NSManagedObjects by using the NSManagedObjectContext.perform functions. This code is covered in Sendable warnings in Xcode 26 (beta 6) because my NSManagedObject subclasses (autogenerated) are non-Sendable and NSManagedObjectContext.perform function takes a Sendable closure. But I can't really figure out what I should be doing. I realize this pattern is non-ideal for Swift concurrency, but it's what Core Data demands AFAIK. How do I deal with this? let moc = object.managedObjectContext! try await moc.perform { object.completed = true // Capture of 'object' with non-Sendable type 'MySpecialObject' in a '@Sendable' closure try moc.save() } Thanks in advance for your help!

My entity has a startDate (NSTime) attribute where I use the date and time in my detail display of the entity. And in my list, I need to group my entities by day (YYMMDD) based on the start date; and I want to ensure that it can adapt to the region where the user is currently (e.g. if user travels or migrate, the YYMMDD should be adapted based on the current region). Does Core Data SectionedFetchRequest supports strftime() functions from SQLite (https://sqlite.org/lang_datefunc.html) or what is an effective alternative sectioned fetch in my case?

I'm working on a new app with SwiftData and now adding CloudKit Sync. Everything is working fine in the simulator against the development CloudKit Schema. I successfully deployed the schema to production. However, the TestFlight builds fail against production. This is what I see in the logs, but I haven't been able to find info on how to fix it. Help appreciated. CoreData+CloudKit: -[NSCloudKitMirroringDelegate _requestAbortedNotInitialized:](2205): <private> - Never successfully initialized and cannot execute request '<private>' due to error: Error Domain=CKErrorDomain Code=2 "CKInternalErrorDomain: 1011" UserInfo={ContainerID=<private>, NSDebugDescription=CKInternalErrorDomain: 1011, CKPartialErrors=<private>, RequestUUID=<private>, NSLocalizedDescription=<private>, CKErrorDescription=<private>, NSUnderlyingError=0x1078e9fe0 {Error Domain=CKInternalErrorDomain Code=1011 UserInfo={CKErrorDescription=<private>, NSLocalizedDescription=<private>, CKPartialErrors=<private>}}} CoreData+CloudKit: -[NSCloudKitMirroringDelegate _performSetupRequest:]_block_invoke(1153): <private>: Successfully set up CloudKit integration for store (<private>): <private> CoreData+CloudKit: -[NSCloudKitMirroringDelegate _enqueueRequest:]_block_invoke(1035): Failed to enqueue request: <private> Error Domain=NSCocoaErrorDomain Code=134417 UserInfo={NSLocalizedFailureReason=<private>}

As of 2025-05-03, when a macOS user enables iCloud Drive synchronization for Desktop &amp; Documents in US region, does iCloud filter xattrs upon upload or later when downloading back to another macOS host? Or is it the case that iCloud has no filtering of third-party xattrs? Where can I find the technical document outlining exactly what iCloud does with xattrs set on macOS host files and folders synchronized with iCloud Drive?

For a CRM application, I want users to be able to switch between accounts and have their saved contacts stored locally. Whenever a user logs in, the app should fetch data from their specific database location. What’s the best practice to achieve this? Should I create a separate database for each user? Should I store all the data in one database and filter it by user? Or is there a better approach I should consider?

CloudKit CKRecordZone Deletion Issue Problem: CloudKit record zones deleted via CKDatabase.modifyRecordZones(deleting:) or CKModifyRecordZonesOperation are successfully removed but then reappear. I suspect they are automatically reinstated by CloudKit sync, despite successful deletion confirmation. Environment: SwiftData with CloudKit integration Custom CloudKit zones created for legacy zone-based sharing Observed Behavior: Create custom zone (e.g., "TestZone1") via CKDatabase.modifyRecordZones(saving:) Copy records to zone for sharing purposes Delete zone using any CloudKit deletion API - returns success, no errors Immediate verification: Zone is gone from database.allRecordZones() After SwiftData/CloudKit sync or app restart: Zone reappears Reproduction: Tested with three different deletion methods - all exhibit same behaviour: modifyRecordZones(deleting:) async API CKModifyRecordZonesOperation (fire-and-forget) CKModifyRecordZonesOperation with result callbacks Zone deletion succeeds, change tokens (used to track updates to shared records) cleaned up But zones are restored presumably by CloudKit background sync Expected: Deleted zones should remain deleted Actual: Zones are reinstated, creating orphaned zones

I have a single multiplatform application that I use NSPersistentCloudKitContainer on. This works great, except I noticed when I open two instances of the same process (not windows) on the same computer, which share the same store, data duplication and "Metadata Inconsistency" errors start appearing. This answer (https://stackoverflow.com/a/67243833) says this is not supported with NSPersistentCloudKitContainer. Is this indeed true? If it isn't allowed, is the only solution to disable multiple instances of the process via a lock file? I was thinking one could somehow coordinate a single "leader" process that syncs to the cloud, with the others using NSPersistentContainer, but this would be complicated when the "leader" process terminates. Currently, it seems iPad split views are new windows, not processes -- but overall I'm still curious :0 Thank you!

Running Tahoe 26.1 in a virtual machine, I can't sign into my Apple account. There is an error message saying "Could not communicate with the server." Internet access otherwise seems to be working in the VM. I tried both UTM and VirtualBuddy. Is this supposed to work?

Hi, thank you for your reply. I have checked and confirmed that all AppleUser entity fields (id, name, email, password, createdAt) are optional, relationships (posts, comments) are optional, and I assign values when creating a new object, but Core Data still throws a nilError during registration; I have uploaded my project to GitHub for your reference here: https://github.com/Kawiichao/job. If reviewing it requires any payment, please let me know in advance. Thank you very much for your kind offer—I really appreciate it!

Trying to support undo & redo in an app that utilizes Swift Data and as with anything other than provided simplistic Apple demo examples the experience is not great. The problem: Im trying to build functionality that allows users to add items to an item group, where item and item group have a many-to-many relationship e.g. item group can hold many items and items can appear in multiple groups. When trying to do so with relatively simple setup of either adding or removing item group from items relationship array, I am pretty consistently met with a hard crash after performing undo & redo. Sometimes it works the first few undo & redos but 95% of the time would crash on the first one. Could not cast value of type 'Swift.Optional<Any>' (0x20a676be0) to 'Swift.Array<App.CodableStructModel>' (0x207a2bc08). Where CodableStructModel is a Codable Value type inside Item. Adding and removing this relationship should be undoable & redoable as typical for Mac interaction and is "supported" by SwiftData by default, meaning that the developer has to actively either wholly opt out of undo support in their modelContainer setup or do it on a per action scale with the only thing I know of: modelContext.processPendingChanges() modelContext.undoManager?.disableUndoRegistration() ..... modelContext.processPendingChanges() modelContext.undoManager?.enableUndoRegistration() General rant on SwiftData: Random crashes, inconsistencies, random cryptic errors thrown by the debugger and general lack of production level stability. Each update breaks something new and there is very little guidance and communication from the Swift Data team on how to adapt and more importantly consideration for developers that have adopted Swift Data. If SwiftData is not ready for production, it would go a long way to clearly communicate that and mark it as Beta product.