I'm managing the database with SQLite in Flutter. I want to enable iCloud backup and restore on the Swift side when called from Flutter. I am using the following source code, but it is not working. What could be the cause? Could you provide a method and countermeasure? private func saveFileToICloud(fileName: String, localDatabasePath: String, result: @escaping FlutterResult) { guard let containerName = Bundle.main.object(forInfoDictionaryKey: "ICLOUD_CONTAINER_NAME") as? String else { result(FlutterError(code: "NO_ICLOUD_CONTAINER", message: "iCloud container is not available", details: nil)) return } guard let containerURL = FileManager.default.url(forUbiquityContainerIdentifier: containerName) else { result(FlutterError(code: "NO_ICLOUD_CONTAINER", message: "iCloud container is not available", details: nil)) return } let fileURL = containerURL.appendingPathComponent(fileName) let sourceURL = URL(fileURLWithPath: localDatabasePath) do { if FileManager.default.fileExists(atPath: fileURL.path) { try FileManager.default.removeItem(at: fileURL) } try FileManager.default.copyItem(at: sourceURL, to: fileURL) result("File saved successfully to iCloud: \(fileURL.path)") } catch { result(FlutterError(code: "WRITE_ERROR", message: "Failed to write file to iCloud", details: error.localizedDescription)) } } private func readFileFromICloud(fileName: String, localDatabasePath: String, result: @escaping FlutterResult) { let containerName = ProcessInfo.processInfo.environment["ICLOUD_CONTAINER_NAME"] guard let containerURL = FileManager.default.url(forUbiquityContainerIdentifier: containerName) else { result(FlutterError(code: "NO_ICLOUD_CONTAINER", message: "iCloud container is not available", details: nil)) return } let fileURL = containerURL.appendingPathComponent(fileName) let sourceURL = URL(fileURLWithPath: localDatabasePath) do { if FileManager.default.fileExists(atPath: sourceURL.path) { try FileManager.default.removeItem(at: sourceURL) } try FileManager.default.copyItem(at: fileURL, to: sourceURL) result("File restored successfully to sqlite: \(sourceURL.path)") } catch { result(FlutterError(code: "READ_ERROR", message: "Failed to read file from iCloud", details: error.localizedDescription)) } }

Are there any differences (either performance or memory considerations) between removing an array of model objects directly using .removeAll() vs using modelContext? Or, are they identical? Attached below is an example to better illustrate the question (i.e., First Way vs Second Way) // Model Definition @Model class GroupOfPeople { let groupName: String @Relationship(deleteRule: .cascade, inverse: \Person.group) var people: [Person] = [] init() { ... } } @Model class Person { let name: String var group: GroupOfPeople? init() { ... } } // First way struct DemoView: View { @Query private groups: [GroupOfPeople] var body: some View { List(groups) { group in DetailView(group: group) } } } struct DetailView: View { let group: GroupOfPeople var body: some View { Button("Delete All Participants") { group.people.removeAll() } } // Second way struct DemoView: View { @Query private groups: [GroupOfPeople] var body: some View { List(groups) { group in DetailView(group: group) } } } struct DetailView: View { @Environment(\.modelContext) private var context let group: GroupOfPeople var body: some View { Button("Delete All Participants") { context.delete(model: Person.self, where: #Predicate { $0.group.name == group.name }) } // assuming group names are unique. more of making a point using modelContext instead }

First off, given that I didn't find a tag for Code Review, I hope I am not out of scope for the forums here. Second, some background. I am a long time Windows Power Shell developer, moving to Swift because I don't like self loathing. :) Currently I am trying to get my head around SwiftData, and experimenting with creating a Service to handle the actual SwiftData functionality, and a Manager to handle various tasks that relate to instances of the Model. I am doing this realizing that it MAY NOT be the best approach, but it gives me reps both producing code and thinking about how to solve a problem, which I think is useful even if the actual product in throw away. That said, I am hoping someone with more experience than I can comment on this approach, especially with respect to expanding to more models, more complex models, lots of data and a desire to use ModelActor eventually. DataManagerApp.swift import SwiftData import SwiftUI @main struct DataManagerApp: App { let container: ModelContainer init() { let schema = Schema([DataModel.self]) let config = ModelConfiguration("SwiftDataStore", schema: schema) do { let modelContainer = try ModelContainer(for: schema, configurations: config) DataService.instance.assignContainer(modelContainer) container = modelContainer } catch { fatalError("Could not configure SwiftData ModelContainer.") } } var body: some Scene { WindowGroup { ContentView() .modelContainer(container) } } } DataModel.swift import Foundation import SwiftData @Model final class DataModel { var date: Date init(date: Date) { self.date = date } } final class DataService { static let instance = DataService() private var modelContainer: ModelContainer? private var modelContext: ModelContext? private init() {} func assignContainer(_ container: ModelContainer) { if modelContainer == nil { modelContainer = container modelContext = ModelContext(modelContainer!) } else { print("Attempted to assign ModelContainer more than once.") } } func addModel(_ dataModel: DataModel) { modelContext?.insert(dataModel) } func removeModel(_ dataModel: DataModel) { modelContext?.delete(dataModel) } } final class ModelManager { static let instance = ModelManager() let dataService: DataService = DataService.instance private init() {} func newModel() { let newModel = DataModel(date: Date.now) DataService.instance.addModel(newModel) } } ContentView.swift import SwiftData import SwiftUI struct ContentView: View { @Environment(\.modelContext) var modelContext @State private var sortOrder = SortDescriptor(\DataModel.date) @Query(sort: [SortDescriptor(\DataModel.date)]) var models: [DataModel] var body: some View { VStack { addButton List { ForEach(models) { model in modelRow(model) } } .listStyle(.plain) } .padding() .toolbar { ToolbarItem(placement: .topBarTrailing) { addButton } } } } private extension ContentView { var addButton: some View { Button("+ Add") { ModelManager.instance.newModel() } } func modelRow(_ model: DataModel) -> some View { HStack { Text(model.date.formatted(date: .numeric, time: .shortened)) Spacer() } } }

Hey folks, I'm having an issue where iCloud sync is only working in the Development environment, not on Prod. I have deployed the schema to Prod through the CloudKit console, although I did it after the app went live on the AppStore. Even though the two schema are identical, iCloud sync just doesn't work on Prod. Things I tried on the code side: Initially I did the most basic SwiftData+CloudKit setup: var modelContainer: ModelContainer { let schema = Schema([Book.self, Goal.self]) let config = ModelConfiguration(isStoredInMemoryOnly: false, cloudKitDatabase: doesUserSyncToiCloud ? .automatic : .none) var container: ModelContainer do { container = try ModelContainer(for: schema, configurations: config) } catch { fatalError() } return container } var body: some Scene { WindowGroup { AnimatedSplashScreen { MainTabView() } } .modelContainer(modelContainer) } This is enough to make iCloud sync work at the Development level. Then when I noticed the issues on Prod I did some digging and found this on the Docs (https://developer.apple.com/documentation/swiftdata/syncing-model-data-across-a-persons-devices): let config = ModelConfiguration() do { #if DEBUG // Use an autorelease pool to make sure Swift deallocates the persistent // container before setting up the SwiftData stack. try autoreleasepool { let desc = NSPersistentStoreDescription(url: config.url) let opts = NSPersistentCloudKitContainerOptions(containerIdentifier: "iCloud.com.example.Trips") desc.cloudKitContainerOptions = opts // Load the store synchronously so it completes before initializing the // CloudKit schema. desc.shouldAddStoreAsynchronously = false if let mom = NSManagedObjectModel.makeManagedObjectModel(for: [Trip.self, Accommodation.self]) { let container = NSPersistentCloudKitContainer(name: "Trips", managedObjectModel: mom) container.persistentStoreDescriptions = [desc] container.loadPersistentStores {_, err in if let err { fatalError(err.localizedDescription) } } // Initialize the CloudKit schema after the store finishes loading. try container.initializeCloudKitSchema() // Remove and unload the store from the persistent container. if let store = container.persistentStoreCoordinator.persistentStores.first { try container.persistentStoreCoordinator.remove(store) } } } #endif modelContainer = try ModelContainer(for: Trip.self, Accommodation.self, configurations: config) } catch { fatalError(error.localizedDescription) } I've no idea why Apple would include this CoreData setup in a SwiftData documentation, but I went ahead and adapted it to my code as well. I see now that some new "assets" were added to my Development schema, but I'm afraid to deploy these changes to Prod, since I'm not even confident that this CoreData setup is necessary in a SwiftData app. Does anyone have any thoughts on this? Have you run into similar issues? Any help would be much appreciated; thanks!

In a document based SwiftData app for macOS, how do you go about opening a (modal) child window connected to the ModelContainer of the currently open document? Using .sheet() does not really result in a good UX, as the appearing view lacks the standard window toolbar. Using a separate WindowGroup with an argument would achieve the desired UX. However, as WindowGroup arguments need to be Hashable and Codable, there is no way to pass a ModelContainer or a ModelContext there: WindowGroup(id: "myWindowGroup", for: MyWindowGroupArguments.self) { $args in ViewThatOpensInAWindow(args: args) } Is there any other way?

I have a CoreData model with two configuration - but several problems. Notably the viewContext only shows data from the .private configuration. Here is the setup: The private configuration holds entities, for example, User and Course and the shared one holds entities, for example, Player and League. I setup the NSPersistentStoreDescriptions to use the same container but with a databaseScope of .private/.shared and with the configuration of "Private"/"Shared". loadPersistentStores() does not report an error. If I try container.initializeCloudKitSchema() only the .private configuration produces CKRecord types. If I create a companion app using one configuration (w/ all entities) the schema initialization creates all CKRecord types AND I can populate some data in the .private and a created CKShare. I see that data in the CloudKit dashboard. If I axe the companion app and run the real thing w/ two configurations, the viewContext only has the .private data. Why? If when querying history I use NSPersistentHistoryTransaction.fetchRequest I get a nil return when using two configurations (but non-nil when using one).

Let's say I have a CloudKit database schema where I have records of type Author that are referenced by multiple records of type Article. I want to delete an Author record if no Article is referencing it. Now consider the following conflict: device A deleted the last Article referencing Author #42 device B uploads a new Article referencing Author #42 at the same time The result should be that Author #42 is not deleted after both operations are finished. But both device don't know from each other changes. So either device B could miss that device A deleted the author. Or device A could have missed that a new Article was uploaded and therefore the Author #42 was deleted right after the upload of device B. I though about using a reference count first. But this won't work if the ref count is part of the Author record. This is because deletions do not use the changeTag to detect lost updates: If device A found a reference count 0 and decides to delete the Author, it might miss that device B incremented the count meanwhile. I currently see two alternatives: Using a second record that outlives the Author to keep the reference count and using an atomic operation to update and delete it. So if the update fails, the delete would fail either. Always adding a new child record to the Author whenever a reference is made. We could call it ReferenceToken. Since child records may not become dangling, CloudKit would stop a deletion, if a new ReferenceToken sets the parent reference to the Author. Are there any better ways doing this?

I'm developing an app that uses CloudKit synchronization with SwiftData and on visionOS I added an App Settings bundle. I have noticed that sometimes, when the app is open and the user changes a setting from the App Settings bundle, the following fatal error occurs: SwiftData/BackingData.swift:831: Fatal error: This model instance was destroyed by calling ModelContext.reset and is no longer usable. The setting is read within the App struct in the visionOS app target using @AppStorage and this value is in turn used to set the passthrough video dimming via the .preferredSurroundingsEffect modifier. The setting allows the user to specify the dimming level as dark, semi dark, or ultra dark. The fatal error appears to occur intermittently although the first time it was observed was after adding the settings bundle. As such, I suspect there is some connection between those code changes and this fatal error even though they do not directly relate to SwiftData.

Hello, I'm currently developing an app using SwiftData. I want the app to use CloudKit to sync data, so I made sure all my model properties are optional. I've defined a Codable enum as follows: enum Size: Int, Codable { case small case medium case large } I've defined a Drink SwiftData model as follows: @Model class Drink { var name: String? var size: Size? init( name: String? = nil, size: Size? = nil ) { self.name = name self.size = size } } In one of my Views, I want to use a @Query to fetch the data, and use a Predicate to filter the data. The Predicate uses the size enumeration of the Drink model. Here is the code: struct DrinksView: View { @Query var drinks: [Drink] init() { let smallRawValue: Int = Size.small.rawValue let filter: Predicate<Drink> = #Predicate<Drink> { drink in if let size: Size = drink.size { return size.rawValue == smallRawValue } else { return false } } _drinks = Query(filter: filter) } var body: some View { List { ForEach(drinks) { drink in Text(drink.name ?? "Unknown Drink") } } } } The code compiles, but when I run the app, it crashes with the following error: Thread 1: Fatal error: Couldn't find \Drink.size!.rawValue on Drink with fields [SwiftData.Schema.PropertyMetadata(name: "name", keypath: \Drink.name, defaultValue: nil, metadata: nil), SwiftData.Schema.PropertyMetadata(name: "size", keypath: \Drink.size, defaultValue: nil, metadata: nil)] How can I filter my data using this optional variable on the Drink model? Thanks, Axel

Hello, thank you Apple for supporting custom store with SwiftData and the Schema type is superb to work with. I have successfully set one up with SQL and have some feedback and issues regarding its APIs. There’s a highlighted message in the documentation about not using internal restricted symbols directly, but they contradict with the given protocols and I am concerned about breaking any App Store rules. Are we allowed to use these? If not, they should be opened up as they’re useful. BackingData is required to set up custom snapshots, initialization, and getting/setting values. And I want to use it with createBackingData() to directly initialize instances from snapshots when transferring them between server and client or concurrency. RelationshipCollection for casting to-many relationships from backing data or checking if an array contains a PersistentModel. SchemaProperty for type erasure in a collection. Schema.Relationship has KeyPath properties, but it is missing for Schema.Attribute and Schema.CompositeAttribute. Which means you can’t purely depend on the schema to map data. I am unable to access the properties of a custom struct type in a predicate unless I use Mirror with schemaMetadata() or CustomStringConvertible on the KeyPath directly to extract it. Trivial, but… the KeyPath property name is inconsistent (it’s all lowercase). It would be nice to retrieve property names from custom struct types, since you are unable access CodingKeys that are auto synthesized by Codable for structs. But I recently realized they’re a part Schema.CompositeAttribute, however I don’t know how to match these without the KeyPath… I currently map my entities using CodingKeys to their PredicateCodableKeyPathProviding.… but I wish for a simpler alternative! It’s unclear how to provide the schema to the snapshot before new models are created. I currently use a static property, but I want to make it flexible if more schemas and configurations are added later on. I considered saving and loading the schema in a temporary location, but doubtful that the KeyPath values will be available as they are not Codable. I suspect schemaMetadata() has the information I need to map the backing data without a schema for snapshots, but as mentioned previously, properties are inaccessible… Allow access to entity metatypes, like value types from SchemaProperty. They’re useful for getting data out of snapshots and casting them to CodingKeys and PredicateCodableKeyPathProviding. They do not carry over when you provide them in the Schema. I am unable to retrieve the primary key from PersistentIdentifier. It seems like once you create one, you can’t get it out, like the DataStoreConfiguration in ModelContainer is not the one you used to set it up. I cannot cast it, it is an entirely different struct? I have to use JSONSerialization to extract it, but I want to get it directly since it is not a column in my database. It is transformed when it goes to/from my tables. It’s unknown how to support some schema options, such as Spotlight and CloudKit. Allow for extending macro options, such as adding options to set as primary key, whether to auto increment, etc… You can create a schema for super and sub entities, but it doesn’t appear you can actually set them up from the @Model macro or use inheritance on these models… SwiftData history tracking seems incomplete for HistoryDelete, because that protocol requires HistoryTombstone, but this type cannot be instantiated, nor does it contain anything useful to infer from. As an aside, I want to create my own custom ModelActor that is a global actor. However, I’m unable to replicate the executor that Apple provides where the executor has a ModelContext, because this type does not conform to Sendable. So how did Apple do this? The documentation doesn’t mention unchecked Sendable, but I figure if the protocol is available then we would be able to set up our own. And please add concurrency features! Anyway, I hope for more continued support in the future and I am looking forward to what’s new this WWDC! 😊

I have a document based SwiftData app in which I would like to implement a persistent cache. For obvious reasons, I would not like to store the contents of the cache in the documents themselves, but in my app's data directory. Is a use case, in which a document based SwiftData app uses not only the ModelContainers from the currently open files, but also a ModelContainer writing a database file in the app's documents directory (for cache, settings, etc.) supported? If yes, how can you inject two different ModelContexts, one tied to the currently open file and one tied to the local database, into a SwiftUI view?

I've developed an app that allow me to send messages to all users by entering a record in Public database. On each users device, the app takes that Public record and creates a record in their Private database to track the Read and Deleted status. It works flawlessly on the simulator and about 1/3 of the devices enrolled in my TestFlight. The other 2/3 are unable to write to their Private database. In fact, the CKContainer.default().privateCloudDatabase.save() operation causes the app to crash if I let it run. I've looked at every Google link and I just can't figure out why this works for 1/3 of the users, but not the other 2/3. Incidentally, the 2/3 of the group that can't save to their Private database are also unable to save their Notification Subscription. All devices are running iOS 18.0 or better iPhone 11 through 16 in testing pool. Each portion of the working/not working group are a mix of iPhone versions. if !found && checkIcloudStatus() { CKContainer.default().privateCloudDatabase.save(loadPrivateData(n: processedMessages[index].recordName)) { returnedRecord, returnedError in print("Adding new message to Private and error is: \(String(describing: returnedError))") DispatchQueue.main.async { self.processedMessages[index].record = returnedRecord ?? CKRecord(recordType: "messages_private") self.processedMessages[index].unRead = true self.processedMessages[index].deleted = false } } } func loadPrivateData(n: String) -> CKRecord { let record = CKRecord(recordType: "messages_private") record["deleted"] = "false" record["messageId"] = n record["unRead"] = "true" return record }

I'm using SwiftData, and I'm using iCloud's CloudKit feature to back up my data. The problem here is that once you start backing up your data, you can't erase it completely. Even if the user adds 4 data and erases 4 again, I'm using about 2.5kb. I don't know how the user using the app will accept this. I'm trying to provide the user with the ability to erase data at once, what should I do??

About 4 months ago, I shipped the first version of my app with 4 versioned schemas that, unintentionally, had the same versionIdentifier of 1.2.0 in 2 of them: V1: 1.0.0 V2: 1.1.0 V3: 1.2.0 V4: 1.2.0 They are ordered correctly in the MigrationPlan, and they are all lightweight. Migration works, SwiftData doesn't crash on init and I haven't encountered any issues related to this. The app syncs with iCloud. Questions, preferable for anybody with knowledge of SwiftData internals: What will break in SwiftData when there are 2 duplicate numbers? Not that I would expect it to be safe, but does it happen to be safe to ship an update that changes V4's version to 1.3.0, what was originally intended?

I am getting the following error while trying to delete a Record Type in Dev container. How do I solve it? invalid attempt to delete user record type

I have an app and widget that share access to a SwiftData container using App Groups. I have implemented a SwiftData migration plan, but I am unsure whether I should allow the widget to perform the migration (in addition to the app). I am concerned about two possible issues: If the app and widget are run at approximately the same time (e.g. the user taps Open after doing a manual update in the App Store), then both the app and widget might try to perform the migration at the same time, which could lead to race conditions / data corruption. If the widget is first to run but the widget gets suspended for some reasons (e.g., iOS decides it's using too many resources), then the migration might be suspended leaving the database in an corrupted state. To me, it feels like the safest option is to only allow the app itself to perform the migration – this will ensure that the migration can only happen once in a safe state. However, this will lead to problems for the widget. For example, if the user does not open the app for several days after an automatic update, the widget will be in a broken state, since it will not be able to open the container until it has been migrated by the app. Possible solutions I'm considering: Allow both the app and widget to perform the migration and cross my fingers. (Ignore Issue 1 and Issue 2) Implement some kind of UserDefaults flag that is set to true during migration, so that the app and widget will avoid performing the migration concurrently. (Solves Issue 1 but not Issue 2) Only perform the migration in the app, and then add code to the widget to detect which container version the widget has access to, so that the widget can continue to work with a v1 container until the app eventually updates it to a v2 container. (Solves Issue 1 and Issue 2, but leads to very convoluted code – especially over time) Things I'm unsure about: Will iOS continue to use v1 of the widget until the app is opened for the first time, at which point v2 of the widget is installed? Or does iOS immediately update the widget to v2 on update? Does iOS immediately refresh the widget timeline on update? Does SwiftData already have some logic to avoid migrations being performed twice, even from different threads? If so, how does it respond if one process tries to access a container while another process is performing a migration? Does anyone have any recommendations about how to handle these possible issues? What are best practices? Cheers!

SwiftData crashes 100% when fetching history of a model that contains an optional codable property that's updated: SwiftData/Schema.swift:389: Fatal error: Failed to materialize a keypath for someCodableID.someID from CrashModel. It is possible that this path traverses a type that does not work with append(), please file a bug report with a test. Would really appreciate some help or even a workaround. Code: import Foundation import SwiftData import Testing struct VaultsSwiftDataKnownIssuesTests { @Test func testCodableCrashInHistoryFetch() async throws { let container = try ModelContainer( for: CrashModel.self, configurations: .init( isStoredInMemoryOnly: true ) ) let context = ModelContext(container) try SimpleHistoryChecker.hasLocalHistoryChanges(context: context) // 1: insert a new value and save let model = CrashModel() model.someCodableID = SomeCodableID(someID: "testid1") context.insert(model) try context.save() // 2: check history it's fine. try SimpleHistoryChecker.hasLocalHistoryChanges(context: context) // 3: update the inserted value before then save model.someCodableID = SomeCodableID(someID: "testid2") try context.save() // The next check will always crash on fetchHistory with this error: /* SwiftData/Schema.swift:389: Fatal error: Failed to materialize a keypath for someCodableID.someID from CrashModel. It is possible that this path traverses a type that does not work with append(), please file a bug report with a test. */ try SimpleHistoryChecker.hasLocalHistoryChanges(context: context) } } @Model final class CrashModel { // optional codable crashes. var someCodableID: SomeCodableID? // these actually work: //var someCodableID: SomeCodableID //var someCodableID: [SomeCodableID] init() {} } public struct SomeCodableID: Codable { public let someID: String } final class SimpleHistoryChecker { static func hasLocalHistoryChanges(context: ModelContext) throws { let descriptor = HistoryDescriptor<DefaultHistoryTransaction>() let history = try context.fetchHistory(descriptor) guard let last = history.last else { return } print(last) } }

I created 2 different schemas, and made a small change to one of them. I added a property to the model called "version". To see if the migration went through, I setup the migration plan to set version to "1.1.0" in willMigrate. In the didMigrate, I looped through the new version of Tags to check if version was set, and if not, set it. I did this incase the willMigrate didn't do what it was supposed to. The app built and ran successfully, but version was not set in the Tag I created in the app. Here's the migration: enum MigrationPlanV2: SchemaMigrationPlan { static var schemas: [any VersionedSchema.Type] { [DataSchemaV1.self, DataSchemaV2.self] } static let stage1 = MigrationStage.custom( fromVersion: DataSchemaV1.self, toVersion: DataSchemaV2.self, willMigrate: { context in let oldTags = try? context.fetch(FetchDescriptor<DataSchemaV1.Tag>()) for old in oldTags ?? [] { let new = Tag(name: old.name, version: "Version 1.1.0") context.delete(old) context.insert(new) } try? context.save() }, didMigrate: { context in let newTags = try? context.fetch(FetchDescriptor<DataSchemaV2.Tag>()) for tag in newTags ?? []{ if tag.version == nil { tag.version = "1.1.0" } } } ) static var stages: [MigrationStage] { [stage1] } } Here's the model container: var sharedModelContainer: ModelContainer = { let schema = Schema(versionedSchema: DataSchemaV2.self) let modelConfiguration = ModelConfiguration(schema: schema, isStoredInMemoryOnly: false) do { return try ModelContainer( for: schema, migrationPlan: MigrationPlanV2.self, configurations: [modelConfiguration]) } catch { fatalError("Could not create ModelContainer: \(error)") } }() I ran a similar test prior to this, and got the same result. It's like the code in my willMigrate isn't running. I also had print statements in there that I never saw printed to the console. I tried to check the CloudKit console for any information, but I'm having issues with that as well (separate post). Anyways, how can I confirm that my migration was successful here?

Hi all, I am using SwiftData and cloudkit and I am having an extremely persistent bug. I am building an education section on a app that's populated with lessons via a local JSON file. I don't need this lesson data to sync to cloudkit as the lessons are static, just need them imported into swiftdata so I've tried to use the modelcontainer like this: static func createSharedModelContainer() -> ModelContainer { // --- Define Model Groups --- let localOnlyModels: [any PersistentModel.Type] = [ Lesson.self, MiniLesson.self, Quiz.self, Question.self ] let cloudKitSyncModels: [any PersistentModel.Type] = [ User.self, DailyTip.self, UserSubscription.self, UserEducationProgress.self // User progress syncs ] However, what happens is that I still get Lesson and MiniLesson record types on cloudkit and for some reason as well, whenever I update the data models or delete and reinstall the app on simulator, the lessons duplicate (what seems to happen is that a set of lessons comes from the JSON file as it should), and then 1-2 seconds later, an older set of lessons gets synced from cloudkit. I can delete the old set of lessons if I just delete the lessons and mini lessons record types, but if I update the data model again, this error reccurrs. Sorry, I don't know if I managed to explain this well but essentially I just want to stop the lessons and minilessons from being uploaded to cloudkit as I think this will fix the problem. Am I doing something wrong with the code?

While reading CkSyncEngine demo project code, I don't find the code to remove items in syncEngine.state.pendingRecordZoneChanges explicitly. I suspect it might occur in two possible places: nextRecordZoneChangeBatch() or ``nextRecordZoneChangeBatch()`, but I can't figure out how it occurs. nextRecordZoneChangeBatch() has the following code: let batch = await CKSyncEngine.RecordZoneChangeBatch(pendingChanges: changes) { recordID in if let contact = contacts[recordID.recordName] { let record = contact.lastKnownRecord ?? CKRecord(recordType: Contact.recordType, recordID: recordID) contact.populateRecord(record) return record } else { // We might have pending changes that no longer exist in our database. We can remove those from the state. syncEngine.state.remove(pendingRecordZoneChanges: [ .saveRecord(recordID) ]) return nil } } (I'll ignore the syncEngine.state.remove(pendingRecordZoneChanges:) in the else clause, because it's unrelated) Could it be that CKSyncEngine.RecordZoneChangeBatch.init(pendingChanges:,recordProvider:) automatically remove a CKRecord when the recordProvider: closure returns a non-nil value? I checked its document, but it doesn't say anything about this. Thanks for any help.