I have a simple model @Model final class Movie: Identifiable { #Index\<Movie\>(\[.name\]) var id = UUID() var name: String var genre: String? init(name: String, genre: String?) { self.name = name self.genre = genre } } I turned on SQL debugging by including '-com.apple.CoreData.SQLDebug 3' argument on launch. When I fetch the data using the following code, it selects 3 records initially, but then also selects each record individually even though I am not referencing any other attributes. var fetchDescriptor = FetchDescriptor\<Movie\>() fetchDescriptor.propertiesToFetch = \[.id, .name\] fetchDescriptor.fetchLimit = 3 do { print("SELECT START") movies = try modelContext.fetch(fetchDescriptor) print("SELECT END") } catch { print("Failed to load Movie model.") } I see it selecting the 3 rows initially, but then it selects each one separately. Why would it do this on the initial fetch? I was hoping to select the data that I want to display and let the system select the entire record only when I access a variable that I did not initially fetch. CoreData: annotation: fetch using NSSQLiteStatement <0x600002158af0> on entity 'Movie' with sql text 'SELECT 1, t0.Z_PK, t0.ZID, t0.ZNAME FROM ZMOVIE t0 LIMIT 3' returned 3 rows with values: ( "<NSManagedObject: 0x600002158d70> (entity: Movie; id: 0xa583c7ed484691c1 <x-coredata://71E60F4C-1A40-4DB7-8CD1-CD76B4C11949/Movie/p1>; data: <fault>)", "<NSManagedObject: 0x600002158d20> (entity: Movie; id: 0xa583c7ed482691c1 <x-coredata://71E60F4C-1A40-4DB7-8CD1-CD76B4C11949/Movie/p2>; data: <fault>)", "<NSManagedObject: 0x600002158f00> (entity: Movie; id: 0xa583c7ed480691c1 <x-coredata://71E60F4C-1A40-4DB7-8CD1-CD76B4C11949/Movie/p3>; data: <fault>)" ) CoreData: annotation: fetch using NSSQLiteStatement <0x600002154d70> on entity 'Movie' with sql text 'SELECT 0, t0.Z_PK, t0.Z_OPT, t0.ZGENRE, t0.ZID, t0.ZNAME FROM ZMOVIE t0 WHERE t0.Z_PK = ? ' returned 1 rows CoreData: annotation: with values: ( "<NSSQLRow: 0x600000c89500>{Movie 1-1-1 genre=\"Horror\" id=4C5CB4EB-95D7-4DC8-B839-D4F2D2E96ED0 name=\"A000036\" and to-manys=0x0}" ) This all happens between the SELECT START and SELECT END print statements. Why is it fulfilling the faults immediately?

I have two recordTypes in CloudKit: Author and Book. The Book records have their parent property set to an Author, enabling hierarchical record sharing (i.e., if an Author record is shared, the participant can see all books associated with that author in their shared database). When syncing with CKSyncEngine, I was expecting handleFetchedRecordZoneChanges to deliver all Author records before their associated Book records. However, unless I’m missing something, the order appears to be random. This randomness forces me to handle two codepaths in my app (opposed to just one) to replicate CloudKit references in my local persistency storage: Book arrives before its Author → I store the Book but defer setting its parent reference until the corresponding Author arrives. Author arrives before its Books → I can immediately set the parent reference when each Book arrives. Is there a way to ensure that Author records always arrive before Book records when syncing with CKSyncEngine? Or is this behavior inherently unordered and I have to implement two codepaths?

Hi everyone, I've recently implemented CKSyncEngine in my app, and I have two questions regarding its behavior: Duplicate FetchedRecordZoneChanges After Sending Changes: I’ve noticed that the engine sometimes receives a FetchedRecordZoneChanges event containing modifications and deletions that were just sent by the same device a few moments earlier. This event arrives after the SentRecordZoneChanges event, and both events share the same recordChangeTag, which results in double-handling the record. Is this expected behavior? I’d like to confirm if this is how CKSyncEngine works or if I might be overlooking something. Handling Initial Sync with a "Sync Screen": When a user opens the app for the first time and already has data stored in iCloud, I need to display a "Sync Screen" temporarily to prevent showing partial data or triggering abrupt, rapid UI changes. I’ve found that canceling current operations, then awaiting sendChanges() and fetchChanges() works well to ensure data is fully synced before dismissing the sync screen: displaySyncScreen = true await syncEngine.cancelOperations() try await syncEngine.sendChanges() try await syncEngine.fetchChanges() displaySyncScreen = false However, I’m unsure if canceling operations like this could lead to data loss or other issues. Is this a safe approach, or would you recommend a better strategy for handling this initial sync state?

Hello, I'm using CoreData + CloudKit and I am facing the following error 134100 "The managed object model version used to open the persistent store is incompatible with the one that was used to create the persistent store." All my schema updates are composed of adding optional attributes to existing entities, adding non-optional attributes (with default value) to existing entities or adding new entities Basically, only things that lightweight migrations can handle. Every time I update the schema, I add a new model version of xcdatamodel - who only has a single configuration (the "Default" one). And I also deploy the updated CloudKit schema from the dashboard. It worked up to v3 of my xcdatamodel, but started to crash for a few users at v4 when I added 16 new attributes (in total) to 4 existing entities. Then again at v5 when I added 2 new optional attributes to 1 existing entity. I'm using a singleton and here is the code: private func generateCloudKitContainer() -> NSPersistentCloudKitContainer { let container = NSPersistentCloudKitContainer(name: "MyAppModel") let fileLocation = URL(...) let description = NSPersistentStoreDescription(url: fileLocation) description.shouldMigrateStoreAutomatically = true description.setOption(true as NSNumber, forKey: NSPersistentHistoryTrackingKey) description.setOption(true as NSNumber, forKey: NSPersistentStoreRemoteChangeNotificationPostOptionKey) let options = NSPersistentCloudKitContainerOptions(containerIdentifier: "iCloud.com.company.MyApp") options.databaseScope = .private description.cloudKitContainerOptions = options container.persistentStoreDescriptions = [description] container.viewContext.automaticallyMergesChangesFromParent = true container.loadPersistentStores { description, error in container.viewContext.mergePolicy = NSMergePolicy(merge: .mergeByPropertyObjectTrumpMergePolicyType) if let error { // Error happens here! } } return container } I can't reproduce it yet. I don't really understand what could lead to this error.

I need to know the current date to query CloudKit data with it, like: let predicate = NSPredicate(format: "publishedAt <= %@", currentDateAndTime) I don't need high precision, even +/- a few minutes is fine, but I can't rely on device's time since the user can manually change it. Researching this myself I see that the most reliable method is to get the date from the server. There are NTP servers, but accessing them requires additional libraries which adds complexity. TrueTime (last updated 6 years ago) and Kronos (updated like once a year) seem outdated, given how much Swift has changed in the past years. I can make an HTTP request to a website like Google or Apple and read the current time from its headers. But I don't know if this method is reliable. I know I can create a dummy record in CloudKit, update it, and read its modificationDate. But it feels hacky. Maybe there is another way to fetch the current date directly from CloudKit? It feels like it should be easy and there is a straightforward solution, but I just can't find it.

I've noticed several crashes that look like they're caused by an index out of bound in internal methods of NSFetchedResultsController. This happens while changes are merged from the persistent store container into the view context. Here's an example of the last exception backtrace. Exactly which internal methods that are called in - [NSFetchedResultsController(PrivateMethods) _core_managedObjectContextDidChange:] vary between crash reports but they all end up crashing from _NSArrayRaiseBoundException. The Core Data stack consists of one persistent store, one persistent store coordinator that the view context is set up to automatically merge changes from, and data is saved to disk from background context. persistentContainer.loadPersistentStores(...) viewContext = persistentContainer.viewContext viewContext.automaticallyMergesChangesFromParent = true backgroundContext = persistentContainer.newBackgroundContext() backgroundContext.mergePolicy = NSMergeByPropertyObjectTrumpMergePolicy backgroundClientContext = persistentContainer.newBackgroundContext() backgroundClientContext.mergePolicy = NSMergeByPropertyObjectTrumpMergePolicy Does anyone have any ideas what could be causing this? Thankful for any ideas or advice on how to investigate further.

I’m getting a 0xdead10cc crash in a basic CoreData/CloudKit application. I only have one CoreData save call and its made when the app is in the foreground and it's minor so I don't think its being caused by that. My best guess is that it's related to background syncing of CloudKit. Does anyone know how to fix it? I've been advised that adding the following code around any saves will fix it, but it seems weird that this is the solution. I would expect the inner CoreData/CloudKit engine to handle this. ProcessInfo().performActivity(reason: "Persisting to context") { // Save to context here } Here is the crashing thread Thread 7: 0 libsystem_kernel.dylib 0x00000001edc086f4 guarded_pwrite_np + 8 (:-1) 1 libsqlite3.dylib 0x00000001ca71b6e4 seekAndWrite + 456 (sqlite3.c:44287) 2 libsqlite3.dylib 0x00000001ca6d5df4 unixWrite + 180 (sqlite3.c:44365) 3 libsqlite3.dylib 0x00000001ca723b90 pagerWalFrames + 872 (sqlite3.c:67093) 4 libsqlite3.dylib 0x00000001ca6d5b14 sqlite3PagerCommitPhaseOne + 316 (sqlite3.c:70409) 5 libsqlite3.dylib 0x00000001ca6c6494 sqlite3BtreeCommitPhaseOne + 172 (sqlite3.c:81106) 6 libsqlite3.dylib 0x00000001ca6c605c vdbeCommit + 1136 (sqlite3.c:94124) 7 libsqlite3.dylib 0x00000001ca69f778 sqlite3VdbeHalt + 1340 (sqlite3.c:94534) 8 libsqlite3.dylib 0x00000001ca6c0618 sqlite3VdbeExec + 42648 (sqlite3.c:103922) 9 libsqlite3.dylib 0x00000001ca6b56c0 sqlite3_step + 960 (sqlite3.c:97886) 10 CoreData 0x00000001a459ab38 _execute + 128 (NSSQLiteConnection.m:4614) 11 CoreData 0x00000001a45fe004 -[NSSQLiteConnection commitTransaction] + 728 (NSSQLiteConnection.m:3278) 12 CoreData 0x00000001a469888c _executeGenerateObjectIDRequest + 388 (NSSQLCore_Functions.m:6021) 13 CoreData 0x00000001a46986a4 -[NSSQLGenerateObjectIDRequestContext executeRequestCore:] + 28 (NSSQLObjectIDRequestContext.m:42) 14 CoreData 0x00000001a45fb380 -[NSSQLStoreRequestContext executeRequestUsingConnection:] + 240 (NSSQLStoreRequestContext.m:183) 15 CoreData 0x00000001a45fb0a8 __52-[NSSQLDefaultConnectionManager handleStoreRequest:]_block_invoke + 60 (NSSQLConnectionManager.m:307) 16 CoreData 0x00000001a45fafe0 __37-[NSSQLiteConnection performAndWait:]_block_invoke + 48 (NSSQLiteConnection.m:755) 17 libdispatch.dylib 0x00000001a4357fa8 _dispatch_client_callout + 20 (object.m:576) 18 libdispatch.dylib 0x00000001a43677fc _dispatch_lane_barrier_sync_invoke_and_complete + 56 (queue.c:1104) 19 CoreData 0x00000001a45b5ba4 -[NSSQLiteConnection performAndWait:] + 176 (NSSQLiteConnection.m:752) 20 CoreData 0x00000001a45b5a68 -[NSSQLDefaultConnectionManager handleStoreRequest:] + 248 (NSSQLConnectionManager.m:302) 21 CoreData 0x00000001a45b5938 -[NSSQLCoreDispatchManager routeStoreRequest:] + 228 (NSSQLCoreDispatchManager.m:60) 22 CoreData 0x00000001a45b573c -[NSSQLCore dispatchRequest:withRetries:] + 172 (NSSQLCore.m:4044) 23 CoreData 0x00000001a46737b4 -[NSSQLCore _obtainPermanentIDsForObjects:withNotification:error:] + 1324 (NSSQLCore.m:2830) 24 CoreData 0x00000001a460ba98 -[NSSQLCore _prepareForExecuteRequest:withContext:error:] + 272 (NSSQLCore.m:2946) 25 CoreData 0x00000001a460a0f8 __65-[NSPersistentStoreCoordinator executeRequest:withContext:error:]_block_invoke.547 + 8988 (NSPersistentStoreCoordinator.m:2995) 26 CoreData 0x00000001a45d6660 -[NSPersistentStoreCoordinator _routeHeavyweightBlock:] + 264 (NSPersistentStoreCoordinator.m:668) 27 CoreData 0x00000001a45ded28 -[NSPersistentStoreCoordinator executeRequest:withContext:error:] + 1200 (NSPersistentStoreCoordinator.m:2810) 28 CoreData 0x00000001a4655988 -[NSManagedObjectContext save:] + 984 (NSManagedObjectContext.m:1593) 29 CoreData 0x00000001a46f47dc __52+[NSCKEvent beginEventForRequest:withMonitor:error:]_block_invoke_2 + 352 (NSCKEvent.m:76) 30 CoreData 0x00000001a45c28f0 developerSubmittedBlockToNSManagedObjectContextPerform + 476 (NSManagedObjectContext.m:3984) 31 libdispatch.dylib 0x00000001a4357fa8 _dispatch_client_callout + 20 (object.m:576) 32 libdispatch.dylib 0x00000001a43677fc _dispatch_lane_barrier_sync_invoke_and_complete + 56 (queue.c:1104) 33 CoreData 0x00000001a4615c34 -[NSManagedObjectContext performBlockAndWait:] + 308 (NSManagedObjectContext.m:4108) 34 CoreData 0x00000001a46f45ac __52+[NSCKEvent beginEventForRequest:withMonitor:error:]_block_invoke + 192 (NSCKEvent.m:66) 35 CoreData 0x00000001a4825e68 -[PFCloudKitStoreMonitor performBlock:] + 92 (PFCloudKitStoreMonitor.m:148) 36 CoreData 0x00000001a46f4394 +[NSCKEvent beginEventForRequest:withMonitor:error:] + 256 (NSCKEvent.m:61) 37 CoreData 0x00000001a47cc6ec __57-[NSCloudKitMirroringDelegate _performExportWithRequest:]_block_invoke + 260 (NSCloudKitMirroringDelegate.m:1433) 38 CoreData 0x00000001a47c9970 __92-[NSCloudKitMirroringDelegate _openTransactionWithLabel:assertionLabel:andExecuteWorkBlock:]_block_invoke + 72 (NSCloudKitMirroringDelegate.m:957) 39 libdispatch.dylib 0x00000001a4356248 _dispatch_call_block_and_release + 32 (init.c:1549) 40 libdispatch.dylib 0x00000001a4357fa8 _dispatch_client_callout + 20 (object.m:576) 41 libdispatch.dylib 0x00000001a435f5cc _dispatch_lane_serial_drain + 768 (queue.c:3934) 42 libdispatch.dylib 0x00000001a4360158 _dispatch_lane_invoke + 432 (queue.c:4025) 43 libdispatch.dylib 0x00000001a436b38c _dispatch_root_queue_drain_deferred_wlh + 288 (queue.c:7193) 44 libdispatch.dylib 0x00000001a436abd8 _dispatch_workloop_worker_thread + 540 (queue.c:6787) 45 libsystem_pthread.dylib 0x0000000227213680 _pthread_wqthread + 288 (pthread.c:2696) 46 libsystem_pthread.dylib 0x0000000227211474 start_wqthread + 8 (:-1)

I'm beta-testing a CloudKit-based app. One of my testers suddenly reported that they got a .badContainer CloudKit error: <CKError 0x302619800:"Bad Container" (5/1014); server message = "Invalid container to get bundle ids"; op = <...>; uuid = <...>; container ID = "<...>"> (all private info replaced with <...>) The container ID in the message was exactly what I expected, and exactly what other users are successfully using. When I followed up on the report, the user said she tried again later and everything was fine. It's still working fine days later. What could cause a user to get a .badContainer message, when all other users using the same app are fine, the container ID makes sense, and future runs work fine? Is this something I need to worry about? Does it maybe sometimes happen when CloudKit is having some kind of outage?

I am using SwiftData for storage and have a view that uses the @Query property wrapper with a sort descriptor that points to a relationship on a model. In a release build on device running iOS 18.3, the app crashes. This is the line that crashes: @Query(sort: \Item.info.endDate, order: .reverse) private var items: [Item] Item has a relationship to ItemInfo, which is where the endDate property is defined. This code works in debug and on a simulator. In the project referenced here: https://github.com/lepolt/swiftdata-crash, change the scheme build configuration to “Release” and run on device. The app will crash. Using Xcode Version 16.2 (16C5032a) iPhone 12, iOS 18.3 (22D60)

For the past several days every time I log in to to the Cloudkit dashboard I get Error looking up Developer Teams, Please sign out and try again. No amount of singing out and back in changes anything.

SwiftData ModelContainer instances don't seem to have a value for setting the Data Protection class. Is the best way to set that by setting the Data Protection in the app capabilities? Is that the only way? I have a need for log data that would be "Complete unless open" and user data that would be "Complete", but how do I change one of the containers data protection class?

iOS 18.2, Swift, Xcode 16.2 I have a Core Data model with two entities - WarehouseArea (of which there is only one object) and StockReeipt (of which there are a couple of hundred thousand). Each StockReceipt must be linked to a WarehouseArea, and a WarehouseArea can be linked to zero, one or many StockReceipts. My problem is that when I create and add one more StockReceipt, the Core Data save takes over 3 seconds to complete. I don't understand why this is so slow. Saving the initial 200,000 StockReceipts only takes 5-6 seconds. When I enable SQL logging I can see that when the WarehouseArea attribute is being set on a StockReceipt, Core Data fetches all of the other StockReceipts (I don't know why) but that only takes 0.2 seconds and none of those StockReceipts are modified, so there shouldn't be any need to process them when saving the context. I have prepared a test project which can be found at https://github.com/DaleReilly/CoreDataSaveTester . Running the project will produce NSLog output showing the times before and after the slow save. Please help me understand what is going on in the background and tell me if there is any way I can speed this up?

I'm using SwiftData with CloudKit and have been trying to migrate from SchemaV1 to SchemaV2, but it seems reducing the Entities crashes my app. // Example of migrating from V1 to V2 // Dropping `Person` because it's no longer needed do { // SchemaV1: Person.self, Author.self // SchemaV2: Author.self let schema = Schema(versionedSchema: SchemaV2.self) return try ModelContainer( for: schema, migrationPlan: AppSchemaMigrationPlan.self, configurations: ModelConfiguration( cloudKitDatabase: .automatic) ) } catch { fatalError("Could not create ModelContainer: \(error)") } Is it possible to drop Entities in the Schema Migration Plan? How can I delete the Person model from my Schema and CloudKit?

SwiftData delete isn't working, when I attempt to delete a model, my app crashes and I get the following error: SwiftData/PersistentModel.swift:359: Fatal error: Cannot remove My_App.Model2 from relationship Relationship - name: model2, options: [], valueType: Model2, destination: Model2, inverseName: models3, inverseKeypath: Optional(\Model2.models3) on My_App.Model3 because an appropriate default value is not configured. I get that it's saying I don't have a default value, but why do I need one? Isn't @Relationship .cascade automatically deleting the associated models? And onto of that, why is the error occurring within the do block, shouldn't it be caught by the catch, and printed? I have put together a sample project below. import SwiftUI import SwiftData @main struct MyApp: App { var body: some Scene { WindowGroup { ContentView() .modelContainer(for: Model3.self) } } } @Model class Model1 { var name: String @Relationship(deleteRule: .cascade, inverse: \Model2.model1) var models2: [Model2] = [] init(name: String) { self.name = name } } @Model class Model2 { var name: String var model1: Model1 @Relationship(deleteRule: .cascade, inverse: \Model3.model2) var models3: [Model3] = [] init(name: String, model1: Model1) { self.name = name self.model1 = model1 } } @Model class Model3 { var name: String var model2: Model2 init(name: String, model2: Model2) { self.name = name self.model2 = model2 } } struct ContentView: View { @Query var models1: [Model1] @Environment(\.modelContext) var modelContext var body: some View { NavigationStack { List(models1) { model1 in Text(model1.name) .swipeActions { Button("Delete", systemImage: "trash", role: .destructive) { modelContext.delete(model1) do { try modelContext.save() //SwiftData/PersistentModel.swift:359: Fatal error: Cannot remove My_App.Model2 from relationship Relationship - name: model2, options: [], valueType: Model2, destination: Model2, inverseName: models3, inverseKeypath: Optional(\Model2.models3) on My_App.Model3 because an appropriate default value is not configured. } catch { print(error.localizedDescription) } } } } .toolbar { Button("Insert", systemImage: "plus") { modelContext.insert(Model3(name: "model3", model2: Model2(name: "model2", model1: Model1(name: "model1")))) } } } } }

I am attempting to migrate a cloudkit module that calls on manual cloudkit methods for fetching record zone changes, modifying records, etc to one that utilizes CKSyncEngine. I've got a basic implementation working with just a create method for one of my data models, however it seems like the sync engine keeps calling sync events on the same pending changes. Here is my current flow: The user will hit some button that lets them fill out a form to create a data model. The user saves the form. This triggers a method that takes the resulting data model and queues it to the sync engine's state (engine.state.add(pendingRecordZoneChanges: pendingChanges) I have my delegate method nextRecordZoneChangeBatch(_ context:...) implemented where it fetches the corresponding data model using the record ID and returns a batch containing the corresponding populated record from the data model. I have the handleEvent(_ event:...) delegate method implemented where I handle both .fetchRecordZoneChanges and .sentRecordZoneChanges. I have set up .sentRecordZoneChanges to merge the server record into my local record (and persisted locally) so that the record change tags are the same. After this last portion, it seems that the sync engine continues to keep pushing syncs/updates and I end up with numerous handleEvent(_ event:) calls that keep returning savedRecords (and occasionally failedRecordSaves). Am I missing some step to remove the record from the changes after the sync engine recognizes that I have properly saved the record to the server?

I'm developing a SwiftUI app using SwiftData and encountering a persistent issue: Error Message: Thread 1: Fatal error: Duplicate keys of type 'Bland' were found in a Dictionary. This usually means either that the type violates Hashable's requirements, or that members of such a dictionary were mutated after insertion. Details: Occurrence: The error always occurs on the first launch of the app after installation. Specifically, it happens approximately 1 minute after the app starts. Inconsistent Behavior: Despite no changes to the code or server data, the error occurs inconsistently. Data Fetching Process: I fetch data for entities (Bland, CrossZansu, and Trade) from the server using the following process: Fetch Bland and CrossZansu entities via URLSession. Insert or update these entities into the SwiftData context. The fetched data is managed as follows: func refleshBlandsData() async throws { if let blandsOnServer = try await DataModel.shared.getBlands() { await MainActor.run { blandsOnServer.forEach { blandOnServer in if let blandOnLocal = blandList.first(where: { $0.code == blandOnServer.code }) { blandOnLocal.update(serverBland: blandOnServer) } else { modelContext.insert(blandOnServer.bland) } } } } } This is a simplified version of my StockListView. The blandList is a @Query property and dynamically retrieves data from SwiftData: struct StockListView: View { @Environment(\.modelContext) private var modelContext @Query(sort: \Bland.sname) var blandList: [Bland] @Query var users: [User] @State private var isNotLoaded = true @State private var isLoading = false @State private var loadingErrorState = "" var body: some View { NavigationStack { List { ForEach(blandList, id: \.self) { bland in NavigationLink(value: bland) { Text(bland.sname) } } } .navigationTitle("Stock List") .onAppear { doIfFirst() } } } // This function handles data loading when the app launches for the first time func doIfFirst() { if isNotLoaded { loadDataWithAnimationIfNotLoading() isNotLoaded = false } } // This function ensures data is loaded with an animation and avoids multiple triggers func loadDataWithAnimationIfNotLoading() { if !isLoading { isLoading = true Task { do { try await loadData() } catch { // Capture and store any errors during data loading loadingErrorState = "Data load failed: \(error.localizedDescription)" } isLoading = false } } } // Fetch data from the server and insert it into the SwiftData model context func loadData() async throws { if let blandsOnServer = try await DataModel.shared.getBlands() { for bland in blandsOnServer { // Avoid inserting duplicate keys by checking for existing items in blandList if !blandList.contains(where: { $0.code == bland.code }) { modelContext.insert(bland.bland) } } } } } Entity Definitions: Here are the main entities involved: Bland: @Model class Bland: Identifiable { @Attribute(.unique) var code: String var sname: String @Relationship(deleteRule: .cascade, inverse: \CrossZansu.bland) var zansuList: [CrossZansu] @Relationship(deleteRule: .cascade, inverse: \Trade.bland) var trades: [Trade] } CrossZansu: @Model class CrossZansu: Equatable { @Attribute(.unique) var id: String var bland: Bland? } Trade: @Model class Trade { @Relationship(deleteRule: .nullify) var user: User? var bland: Bland } User: class User { var id: UUID @Relationship(deleteRule: .cascade, inverse: \Trade.user) var trades: [Trade] } Observations: Error Context: The error occurs after the data is fetched and inserted into SwiftData. This suggests an issue with Hashable requirements or duplicate keys being inserted unintentionally. Concurrency Concerns: The fetch and update operations are performed in asynchronous tasks. Could this cause race conditions? Questions: Could this issue be related to how @Relationship and @Attribute(.unique) are managed in SwiftData? What are potential pitfalls with Equatable implementations (e.g., in CrossZansu) when used in SwiftData entities? Are there any recommended approaches for debugging "Duplicate keys" errors in SwiftData? Additional Info: Error Timing: The error occurs only during the app's first launch and consistently within the first minute.

I get this message when trying to save my Models. CoreData: error: SQLCore dispatchRequest: exception handling request: <NSSQLSaveChangesRequestContext: 0x303034540> , I/O error for database at /var/mobile/Containers/Data/Application/726ECA8C-6C67-4BFE-89E7-AFD8A83CAA5D/Library/Application Support/default.store. SQLite error code:1, 'no such table: ZCALENDARMODEL' with userInfo of { NSFilePath = "/var/mobile/Containers/Data/Application/726ECA8C-6C67-4BFE-89E7-AFD8A83CAA5D/Library/Application Support/default.store"; NSSQLiteErrorDomain = 1; } SwiftData.DefaultStore save failed with error: Error Domain=NSCocoaErrorDomain Code=256 "The file “default.store” couldn’t be opened." UserInfo={NSFilePath=/var/mobile/Containers/Data/Application/726ECA8C-6C67-4BFE-89E7-AFD8A83CAA5D/Library/Application Support/default.store, NSSQLiteErrorDomain=1} The App has Recipes and Calendars and the user can select a Recipe for each Calendar day. The recipe should not be referenced, it should be saved by SwiftData along with the Calendar. import SwiftUI import SwiftData enum CalendarSource: String, Codable { case created case imported } @Model class CalendarModel: Identifiable, Codable { var id: UUID = UUID() var name: String var startDate: Date var endDate: Date var recipes: [String: RecipeData] = [:] var thumbnailData: Data? var source: CalendarSource? // Computed Properties var daysBetween: Int { let days = Calendar.current.dateComponents([.day], from: startDate.midnight, to: endDate.midnight).day ?? 0 return days + 1 } var allDates: [Date] { startDate.midnight.allDates(upTo: endDate.midnight) } var thumbnailImage: Image? { if let data = thumbnailData, let uiImage = UIImage(data: data) { return Image(uiImage: uiImage) } else { return nil } } // Initializer init(name: String, startDate: Date, endDate: Date, thumbnailData: Data? = nil, source: CalendarSource? = .created) { self.name = name self.startDate = startDate self.endDate = endDate self.thumbnailData = thumbnailData self.source = source } // Convenience initializer to create a copy of an existing calendar static func copy(from calendar: CalendarModel) -> CalendarModel { let copiedCalendar = CalendarModel( name: calendar.name, startDate: calendar.startDate, endDate: calendar.endDate, thumbnailData: calendar.thumbnailData, source: calendar.source ) // Copy recipes copiedCalendar.recipes = calendar.recipes.mapValues { $0 } return copiedCalendar } // Codable Conformance private enum CodingKeys: String, CodingKey { case id, name, startDate, endDate, recipes, thumbnailData, source } required init(from decoder: Decoder) throws { let container = try decoder.container(keyedBy: CodingKeys.self) id = try container.decode(UUID.self, forKey: .id) name = try container.decode(String.self, forKey: .name) startDate = try container.decode(Date.self, forKey: .startDate) endDate = try container.decode(Date.self, forKey: .endDate) recipes = try container.decode([String: RecipeData].self, forKey: .recipes) thumbnailData = try container.decodeIfPresent(Data.self, forKey: .thumbnailData) source = try container.decodeIfPresent(CalendarSource.self, forKey: .source) } func encode(to encoder: Encoder) throws { var container = encoder.container(keyedBy: CodingKeys.self) try container.encode(id, forKey: .id) try container.encode(name, forKey: .name) try container.encode(startDate, forKey: .startDate) try container.encode(endDate, forKey: .endDate) try container.encode(recipes, forKey: .recipes) try container.encode(thumbnailData, forKey: .thumbnailData) try container.encode(source, forKey: .source) } } import SwiftUI struct RecipeData: Codable, Identifiable { var id: UUID = UUID() var name: String var ingredients: String var steps: String var thumbnailData: Data? // Computed property to convert thumbnail data to a SwiftUI Image var thumbnailImage: Image? { if let data = thumbnailData, let uiImage = UIImage(data: data) { return Image(uiImage: uiImage) } else { return nil // No image } } init(recipe: RecipeModel) { self.name = recipe.name self.ingredients = recipe.ingredients self.steps = recipe.steps self.thumbnailData = recipe.thumbnailData } } import SwiftUI import SwiftData @Model class RecipeModel: Identifiable, Codable { var id: UUID = UUID() var name: String var ingredients: String var steps: String var thumbnailData: Data? // Store the image data for the thumbnail static let fallbackSymbols = ["book.pages.fill", "carrot.fill", "fork.knife", "stove.fill"] // Computed property to convert thumbnail data to a SwiftUI Image var thumbnailImage: Image? { if let data = thumbnailData, let uiImage = UIImage(data: data) { return Image(uiImage: uiImage) } else { return nil // No image } } // MARK: - Initializer init(name: String, ingredients: String = "", steps: String = "", thumbnailData: Data? = nil) { self.name = name self.ingredients = ingredients self.steps = steps self.thumbnailData = thumbnailData } // MARK: - Copy Function func copy() -> RecipeModel { RecipeModel( name: self.name, ingredients: self.ingredients, steps: self.steps, thumbnailData: self.thumbnailData ) } // MARK: - Codable Conformance private enum CodingKeys: String, CodingKey { case id, name, ingredients, steps, thumbnailData } required init(from decoder: Decoder) throws { ... } func encode(to encoder: Encoder) throws { var container = encoder.container(keyedBy: CodingKeys.self) try container.encode(id, forKey: .id) try container.encode(name, forKey: .name) try container.encode(ingredients, forKey: .ingredients) try container.encode(steps, forKey: .steps) try container.encode(thumbnailData, forKey: .thumbnailData) } }

In a CloudKit private database, the Owner creates a custom zone and performs the following actions: Creates CKRecord1 with CKShare1 and invites Participant1 to it. Creates CKRecord2 with CKShare2 and invites Participant2 to it. Creates CKRecordShared, which should be accessible to both Participant1 and Participant2. How can I achieve step 3? I observed that: Setting a regular reference from CKRecord1 (or CKRecord2) to CKRecordShared does not automatically make CKRecordShared accessible to Participant1 (or Participant2). CKRecordShared can only have one parent, so it cannot be directly linked via parent reference to both Participant1 and Participant2 at the same time. One potential solution I see is to have the Owner create a separate CKShare for CKRecordShared and share it explicitly with each participant. However, this approach could lead to user errors, as it requires careful management of multiple shares for each participant. Is there a better way to handle this scenario, ensuring that CKRecordShared is accessible to multiple participants without introducing unnecessary complexity or potential errors?

I am trying to read and write a text file from an App written in Swift in XCode directly to the "iCloud Drive" folder in Files on the iPhone. The app worked readlly reading and writing to the Documents folder in the App container, and then readily to the "On My iPhone" folder in Files after adding 2 lines to the plist that I found in a search online. But I have been unable to get to the iCloud Drive folder. I found an item called "Enabling Document Storage in iCloud Drive" in "iCloud Design Guide" with additional plist entries that states "These settings allow iCloud Drive to provide public access to the files stored in your app’s container": NSUbiquitousContainers iCloud.com.example.MyApp NSUbiquitousContainerIsDocumentScopePublic NSUbiquitousContainerSupportedFolderLevels Any NSUbiquitousContainerName MyApp I think I changed the MyApp items appropriately. I have enabled iCloud in my App and the XCode General, and Signing entries. But this does not work. There are no error messages and no "Steps" shown in the "Capabilities" entry in Xcode. A little help? :-)

relationshipKeyPathsForPrefetching in SwiftData does not seem to work here when scrolling down the list. Why? I would like all categories to be fetched while posts are fetched - not while scrolling down the list. struct ContentView: View { var body: some View { QueryList( fetchDescriptor: withCategoriesFetchDescriptor ) } var withCategoriesFetchDescriptor: FetchDescriptor<Post> { var fetchDescriptor = FetchDescriptor<Post>() fetchDescriptor.relationshipKeyPathsForPrefetching = [\.category] return fetchDescriptor } } struct QueryList: View { @Query var posts: [Post] init(fetchDescriptor: FetchDescriptor<Post>) { _posts = Query(fetchDescriptor) } var body: some View { List(posts) { post in VStack { Text(post.title) Text(post.category?.name ?? "") .font(.footnote) } } } } @Model final class Post { var title: String var category: Category? init(title: String) { self.title = title } } @Model final class Category { var name: String init(name: String) { self.name = name } }