I previously got this error when I used a PassKey to log in. I'm not using that. I've put my password in multiple times, closed the browser, etc. It doesn't seem to be working. The only thing I can think is that because my Mac is using a different iCloud account, it's not letting me. Does anyone have any ideas?

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?

struct ModelContainerSetup { static let shared = ModelContainerSetup() private static let containerIdentifier = "iCloud.Journal" func setupModelContainer() -> ModelContainer { let schema = Schema([User.self]) let modelConfiguration = ModelConfiguration( schema: schema, isStoredInMemoryOnly: false, cloudKitDatabase: .private(Self.containerIdentifier) ) do { return try ModelContainer(for: schema, configurations: [modelConfiguration]) } catch { fatalError("Could not create ModelContainer: \(error)") } } **Expected Behavior: ** When CloudKit storage is full, the app should continue functioning with local storage Data should persist locally even if cloud sync fails Sync should resume when storage becomes available **Actual Behavior: ** ModelContainer initialization fails completely Local data also stops getting saved **Environment: ** iOS 17.0+ SwiftData Private CloudKit database Ideal Behaviour: When iCloud fails, the data should still be saved locally. I do not want to have two different containers so that I can maintain data consistency.

I've been trying to setup a successful migration, but it keeps failing with this error: NSCloudKitMirroringDelegate are not reusable and should have a lifecycle tied to a given instance of NSPersistentStore. I can't find any information about this online. I added breakpoints throughout the code in willMigrate, and it originally failed on this line: try? context.save() I removed that, and it still failed. After I reload the app, it doesn't run the migration again and the app loads successfully. I figured since it crashed, it would keep trying, but I guess not. Here's how my migration is setup. enum MigrationV1ToV2: SchemaMigrationPlan { static var schemas: [any VersionedSchema.Type] { [SchemaV1.self, SchemaV2.self] } static var stages: [MigrationStage] { [stage] } static let stage = MigrationStage.custom( fromVersion: SchemaV1.self, toVersion: SchemaV2.self, willMigrate: { context in // Get cycles let cycles = try? context.fetch(FetchDescriptor<SchemaV1.Cycle>()) if let cycles { for cycle in cycles { // Create new recurring objects based on what's in the cycle for income in cycle.income { let recurring = SchemaV2.Recurring(name: income.name, frequency: income.frequency, kind: .income) recurring.addAmount(.init(date: cycle.startDate, amount: income.amount)) context.insert(recurring) } for expense in cycle.expenses { let recurring = SchemaV2.Recurring(name: expense.name, frequency: expense.frequency, kind: .expense) recurring.addAmount(.init(date: cycle.startDate, amount: expense.amount)) context.insert(recurring) } for savings in cycle.savings { let recurring = SchemaV2.Recurring(name: savings.name, frequency: savings.frequency, kind: .savings) recurring.addAmount(.init(date: cycle.startDate, amount: savings.amount)) context.insert(recurring) } for investment in cycle.investments { let recurring = SchemaV2.Recurring(name: investment.name, frequency: investment.frequency, kind: .investment) recurring.addAmount(.init(date: cycle.startDate, amount: investment.amount)) context.insert(recurring) } } //try? context.save() } else { print("The cycles were not able to be fetched.") } }, didMigrate: { context in // Get new recurring objects let newRecurring = try? context.fetch(FetchDescriptor<SchemaV2.Recurring>()) if let newRecurring { for recurring in newRecurring { // Get all recurring with the same name and kind let sameName = newRecurring.filter({ $0.name == recurring.name && $0.kind == recurring.kind }) // Add amount history to recurring object, and then remove matching for match in sameName { recurring.amountHistory.append(contentsOf: match.amountHistory) context.delete(match) } } //try? context.save() } else { print("The new recurring objects could not be fetched.") } } ) } Here's is my modelContainer in the app file. There is a fatal error occurring here that's crashing the app. var sharedModelContainer: ModelContainer = { let schema = Schema(versionedSchema: SchemaV2.self) let modelConfiguration = ModelConfiguration(schema: schema, isStoredInMemoryOnly: false) do { return try ModelContainer( for: schema, migrationPlan: MigrationV1ToV2.self, configurations: [modelConfiguration] ) } catch { fatalError("Could not create ModelContainer: \(error)") } }() Does anyone have any suggestions for this? EDIT: I found this error in the console that may be relevant. BUG IN CLIENT OF CLOUDKIT: Registering a handler for a CKScheduler activity identifier that has already been registered (com.apple.coredata.cloudkit.activity.export.8F7A1261-4324-40B4-B041-886DF36FBF0A). CloudKit setup failed because it couldn't register a handler for the export activity. There is another instance of this persistent store actively syncing with CloudKit in this process. And here is the fatal error Fatal error: Could not create ModelContainer: SwiftDataError(_error: SwiftData.SwiftDataError._Error.loadIssueModelContainer, _explanation: nil)

I want to clear all the data in the zone, but I can't delete it. Below is my code, no logs are printed when running. static func clearData() { let coordinator = shared.container.persistentStoreCoordinator let fm = FileManager.default for d in shared.container.persistentStoreDescriptions { guard let url = d.url else { continue } do { if fm.fileExists(atPath: url.path()) { try coordinator.destroyPersistentStore(at: url, type: .sqlite) } } catch { logger.debug("Failed to delete db file, \(error)") } } for description in shared.container.persistentStoreDescriptions { guard let originalStoreURL = description.url else { continue } let walFileURL = originalStoreURL.deletingPathExtension().appendingPathExtension("sqlite-wal") let shmFileURL = originalStoreURL.deletingPathExtension().appendingPathExtension("sqlite-shm") for url in [originalStoreURL, walFileURL, shmFileURL] { do { if fm.fileExists(atPath: url.path()) { try fm.removeItem(at: url) } } catch { logger.debug("Failed to delete db file, \(error)") } } } let container = CKContainer(identifier: appContainerID) container.privateCloudDatabase.fetchAllRecordZones { zones, error in if let error = error { print("Error fetching zones: ") } else if let zone = zones?.first, zone.zoneID.zoneName == "_defaultZone" { PersistenceController.shared.container.purgeObjectsAndRecordsInZone(with: zone.zoneID, in: nil) { ckShare, error in if let error = error { print("Error purge zones: \(error)") } if ckShare == nil { print("ckShare is nil") } } } } }

Both appleIDs(create and modify/save) sign in iCloud. I use the following code to modify and save records: self.containerIdentifier).publicCloudDatabase database.fetch(withRecordID: CKRecord.ID(recordName:groupID), completionHandler: { record, error in if error == nil && record != nil { if let iDs : [String] = record!.object(forKey: "memberIDs") as? Array { if iDs.count < self.maxMemberCount { if let mems: [String] = record!.object(forKey: "memberNames") as? Array { if !(mems as NSArray).contains(name) { var members = mems members.append(name) record!.setObject(members as CKRecordValue, forKey: "memberNames") var iDs : [String] = record!.object(forKey: "memberIDs") as! Array iDs.append(self.myMemberID) record!.setObject(iDs as CKRecordValue, forKey:"memberIDs") database.save(record!, completionHandler: { record, error in if error == nil { } else { completion(error as NSError?) dPrint("Error : \(String(describing: error))") } }) }else{ let DBError : NSError = NSError(domain: "DBError", code: 89, userInfo: ["localizedDescription": NSLocalizedString("Your nickname already used.", comment:"")]) completion(DBError) print("change your nickname") } }else{ print("group DB error") let DBError : NSError = NSError(domain: "DBError", code: 88, userInfo: ["localizedDescription": NSLocalizedString("Please try later.", comment:"")]) completion(DBError) } } }else{ print("Error : \(String(describing: error))") } }) I received the following error message: ?Error saving records: <CKError 0x600000bbe970: "Service Unavailable" (6/NSCocoaErrorDomain:4099); "Error connecting to CloudKit daemon. This could happen for many reasons, for example a daemon exit, a device reboot, a race with the connection inactivity monitor, invalid entitlements, and more. Check the logs around this time to investigate the cause of this error."; Retry after 5.0 seconds> baseNSError@0 NSError domain: "CKErrorDomain" - code: 6 _userInfo __NSDictionaryI * 4 key/value pairs 0x000060000349e300 [0] (null) "NSLocalizedDescription" : "Error connecting to CloudKit daemon. This could happen for many reasons, for example a daemon exit, a device reboot, a race with the connection inactivity monitor, invalid entitlements, and more. Check the logs around this time to investigate the cause of this error." key __NSCFConstantString * "NSLocalizedDescription" 0x00000001117155a0 value __NSCFConstantString * "Error connecting to CloudKit daemon. This could happen for many reasons, for example a daemon exit, a device reboot, a race with the connection inactivity monitor, invalid entitlements, and more. Check the logs around this time to investigate the cause of this error." 0x000000011057e700 [1] (null) "CKRetryAfter" : Int32(5) key __NSCFConstantString * "CKRetryAfter" 0x000000011057c680 value NSConstantIntegerNumber? Int32(5) 0x00000001105c2ed0 [2] (null) "CKErrorDescription" : "Error connecting to CloudKit daemon. This could happen for many reasons, for example a daemon exit, a device reboot, a race with the connection inactivity monitor, invalid entitlements, and more. Check the logs around this time to investigate the cause of this error." key __NSCFConstantString * "CKErrorDescription" 0x0000000110568d00 value __NSCFConstantString * "Error connecting to CloudKit daemon. This could happen for many reasons, for example a daemon exit, a device reboot, a race with the connection inactivity monitor, invalid entitlements, and more. Check the logs around this time to investigate the cause of this error." 0x000000011057e700 [3] (null) "NSUnderlyingError" : domain: "NSCocoaErrorDomain" - code: 4099 key __NSCFConstantString * "NSUnderlyingError" 0x0000000111715540 value NSError? domain: "NSCocoaErrorDomain" - code: 4099 0x00006000016cc300

While reading the developer documentation article Adopting SwiftData for a Core Data App, one particular line piqued my interest. For apps that evolve from a version that doesn’t have any app group container to a version that has one, SwiftData copies the existing store to the app group container. Given how troublesome it has been to migrate the Core Data persistent store to an app group container, I decided to try this out myself. I created an Xcode project using the default Core Data template. I then added a few Item objects with timestamps. There, I had what we would consider a regular Core Data app. I then created a widget extension for this app since this is one of the most common uses for adopting an app group in an Xcode project. After that, I linked the main target with the widget extension using an app group. In the widget extension, I tried to fetch the Item objects. I utilized the SwiftData code in the sample project associated with the article above. struct Provider: TimelineProvider { private let modelContainer: ModelContainer init() { let appGroupContainerID = "group.com.genebogdanovich.CoreDataSwiftDataAppGroup" guard let appGroupContainer = FileManager.default.containerURL(forSecurityApplicationGroupIdentifier: appGroupContainerID) else { fatalError("Shared file container could not be created.") } let url = appGroupContainer.appendingPathComponent("CoreDataSwiftDataAppGroup.sqlite") print("\(url)") do { modelContainer = try ModelContainer(for: Item.self, configurations: ModelConfiguration(url: url)) } catch { fatalError("Failed to create the model container: \(error)") } } } func getTimeline(in context: Context, completion: @escaping (Timeline<Entry>) -> ()) { Task { @MainActor in let fetchDescriptor = FetchDescriptor<Item>() let items: [Item] = try! modelContainer.mainContext.fetch(fetchDescriptor) print(items) let entry = SimpleEntry(date: .now, emoji: "😀", count: items.count) let timeline = Timeline(entries: [entry], policy: .never) completion(timeline) } } The fetch yielded no results. However, as I explored the app group directory in the file system, I found a .sqlite file. That is interesting because SwiftData creates .store files by default. So, I am guessing that SwiftData did copy something. Or the ModelContainer initializer just created another empty SQLite file since the fetch returned zero results. I would highly appreciate someone elaborating on that quote from the documentation.

I got a preview crash info as this: *** crashed due to fatalError in PersistentModel.swift at line 559. This KeyPath does not appear to relate RecordInfo to anything - \RecordInfo.<computed 0x00000001921dfb4e (Array<SomeInfo>)> If I change preview device to iPhoneSE, It is no crash. I think the reason is I have some dirty data in iPhone16 Pro preview device. If I'm right and how to delete it? Model of RecordInfo like this: @Model class RecordInfo { @Relationship(deleteRule: .cascade) var someInfo:[SomeInfo] } @Model class SomeInfo { var date: Date var info: String }

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 am trying to add a custom JSON DataStore and DataStoreConfiguration for SwiftData. Apple kindly provided some sample code in the WWDC24 session, "Create a custom data store with SwiftData", and (once updated for API changes since WWDC) that works fine. However, when I try to add a relationship between two classes, it fails. Has anyone successfully made a JSONDataStore with a relationship? Here's my code; firstly the cleaned up code from the WWDC session: import SwiftData final class JSONStoreConfiguration: DataStoreConfiguration { typealias Store = JSONStore var name: String var schema: Schema? var fileURL: URL init(name: String, schema: Schema? = nil, fileURL: URL) { self.name = name self.schema = schema self.fileURL = fileURL } static func == (lhs: JSONStoreConfiguration, rhs: JSONStoreConfiguration) -> Bool { return lhs.name == rhs.name } func hash(into hasher: inout Hasher) { hasher.combine(name) } } final class JSONStore: DataStore { typealias Configuration = JSONStoreConfiguration typealias Snapshot = DefaultSnapshot var configuration: JSONStoreConfiguration var name: String var schema: Schema var identifier: String init(_ configuration: JSONStoreConfiguration, migrationPlan: (any SchemaMigrationPlan.Type)?) throws { self.configuration = configuration self.name = configuration.name self.schema = configuration.schema! self.identifier = configuration.fileURL.lastPathComponent } func save(_ request: DataStoreSaveChangesRequest<DefaultSnapshot>) throws -> DataStoreSaveChangesResult<DefaultSnapshot> { var remappedIdentifiers = [PersistentIdentifier: PersistentIdentifier]() var serializedData = try read() for snapshot in request.inserted { let permanentIdentifier = try PersistentIdentifier.identifier(for: identifier, entityName: snapshot.persistentIdentifier.entityName, primaryKey: UUID()) let permanentSnapshot = snapshot.copy(persistentIdentifier: permanentIdentifier) serializedData[permanentIdentifier] = permanentSnapshot remappedIdentifiers[snapshot.persistentIdentifier] = permanentIdentifier } for snapshot in request.updated { serializedData[snapshot.persistentIdentifier] = snapshot } for snapshot in request.deleted { serializedData[snapshot.persistentIdentifier] = nil } try write(serializedData) return DataStoreSaveChangesResult<DefaultSnapshot>(for: self.identifier, remappedIdentifiers: remappedIdentifiers) } func fetch<T>(_ request: DataStoreFetchRequest<T>) throws -> DataStoreFetchResult<T, DefaultSnapshot> where T : PersistentModel { if request.descriptor.predicate != nil { throw DataStoreError.preferInMemoryFilter } else if request.descriptor.sortBy.count > 0 { throw DataStoreError.preferInMemorySort } let objs = try read() let snapshots = objs.values.map({ $0 }) return DataStoreFetchResult(descriptor: request.descriptor, fetchedSnapshots: snapshots, relatedSnapshots: objs) } func read() throws -> [PersistentIdentifier : DefaultSnapshot] { if FileManager.default.fileExists(atPath: configuration.fileURL.path(percentEncoded: false)) { let decoder = JSONDecoder() decoder.dateDecodingStrategy = .iso8601 let data = try decoder.decode([DefaultSnapshot].self, from: try Data(contentsOf: configuration.fileURL)) var result = [PersistentIdentifier: DefaultSnapshot]() data.forEach { s in result[s.persistentIdentifier] = s } return result } else { return [:] } } func write(_ data: [PersistentIdentifier : DefaultSnapshot]) throws { let encoder = JSONEncoder() encoder.dateEncodingStrategy = .iso8601 encoder.outputFormatting = [.prettyPrinted, .sortedKeys] let jsonData = try encoder.encode(data.values.map({ $0 })) try jsonData.write(to: configuration.fileURL) } } The data model classes: import SwiftData @Model class Settings { private(set) var version = 1 @Relationship(deleteRule: .cascade) var hack: Hack? = Hack() init() { } } @Model class Hack { var foo = "Foo" var bar = 42 init() { } } Container: lazy var mainContainer: ModelContainer = { do { let url = // URL to file let configuration = JSONStoreConfiguration(name: "Settings", schema: Schema([Settings.self, Hack.self]), fileURL: url) return try ModelContainer(for: Settings.self, Hack.self, configurations: configuration) } catch { fatalError("Container error: \(error.localizedDescription)") } }() Load function, that saves a new Settings JSON file if there isn't an existing one: @MainActor func loadSettings() { let mainContext = mainContainer.mainContext let descriptor = FetchDescriptor<Settings>() let settingsArray = try? mainContext.fetch(descriptor) print("\(settingsArray?.count ?? 0) settings found") if let settingsArray, let settings = settingsArray.last { print("Loaded") } else { let settings = Settings() mainContext.insert(settings) do { try mainContext.save() } catch { print("Error saving settings: \(error)") } } } The save operation creates a JSON file, which while it isn't a format I would choose, is acceptable, though I notice that the "hack" property (the relationship) doesn't have the correct identifier. When I run the app again to load the data, I get an error (that there wasn't room to include in this post). Even if I change Apple's code to not assign a new identifier, so the relationship property and its pointee have the same identifier, it still doesn't load. Am I doing something obviously wrong, or are relationships not supported in custom data stores?

I have a Core Data app on the App Store that places its persistent store in the default location within the Application Support directory. At some point, I add widgets to the app while utilizing SwiftData. I create a widget extension and the app group to link both targets. I migrate my persistent store from the default location to the app group container directory. Now, the SwiftData code pointing to the shared container in the widget extension can query data. Here's the sample project for illustration up to this point. Then, I decided to get rid of the Core Data code entirely. Move everything in the main target to SwiftData. I need to keep my persistence controller object, however, because I can never assume that the entirety of my user base has migrated. I do need to ditch the Core Data model file. Otherwise, my new SwiftData models would conflict with the auto-generated ones from that file. But once I do that, my migration code breaks. I can't set up a persistent container without the model. And I need the container for migration. SwiftData has no native interface to migrate the store to a new location. There is a line in the documentation stating that the framework copies the store to an app group container automatically. But I wasn't able to verify that claim.

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??

Hello, I recently switched my app from flutter which was using sqlite3 database. I would like to migrate my existing users to SwiftData. The issue is I do not know where to start in finding the database for the current users, reading the data and inserting into the SwiftData schema. I tried searching but not clear on how to proceed. Any help pointing in the right direction would be great. Thanks.

Currently, I have an Unversioned Schema, and lightweight changes are automatically applied to the Models. However, I'm planning to transition to a VersionedSchema, and I have a few questions: Do I need to write all lightweight migrations in the Migration Plan? or is it automatically applied like the Unversioned Schema? What happens if I do not create a lightweight migration? and just directly do lightweight changes to the latest VersionedSchema (example: Add a new property)?

I have been dealing with an error for almost 2 days now that caused my programme to crash on runtime with Thread 10: EXC_BAD_ACCESS (code=1, address=0x0) error , only when using Release mode. After many trial and errors and narrowing down the root problem I became suspicious to #Predicate and Generics being the root cause of the problem so I made these views to test it out. import SwiftUI import SwiftData struct DataBaseTestGeneric<Model : PersistentModel>: View { @State private var models: [Model] = [] var body: some View { viewLoader{ let reporter = Reporter() let pred = #Predicate<Model>{ model in return true } models = await reporter.fetch(pred) }content: { List{ ForEach(models){ model in Text("\(model.id)") } } } } } and a non-Generic version : import SwiftData struct DatabaseTest: View { @State private var transactions: [Transaction] = [] var body: some View { viewLoader { let reporter = Reporter() let pred = #Predicate<Transaction>{ dec in return true } let decs = await reporter.fetch(pred) transactions = decs }content:{ List{ ForEach(transactions){transaction in Text("\(transaction.id)") } } } } } to give you an insight viewLoader implentations is : struct viewLoader<Content : View>: View { var state : LoadingView.States = .loading let loadingTask : () async -> Void @State private var isLoading = true @ViewBuilder var content : Content var body: some View { if isLoading{ LoadingView(state) .task { await Task.detached(priority:.high){ await loadingTask() }.value isLoading = false } }else{ content } } } and I am accessing SwiftData using a background thread ( by implementing @ModelActor . the problem is that the code always crash on runtime when I am trying to fetch the data using reporter.fetch function. To make things even more weird I have to add the fact that Reporter class also have another function called fetchAll as follow : func fetchAll<T>(_ model : T.Type) async -> [T] where T : PersistentModel { let desc = FetchDescriptor<T>() let result = try? await context.fetch(desc) guard let result else { assertionFailure("Error fetching \(model) from context") return [] } return result } if i replace this function with reporter.fetch (which takes a predicate) the code will not crash either with or without using Generics , which brings me to the point that #Predicate is causing mayhem somehow ! PS: I am using Xcode Version 16.1 (16B40) , on macOs Sequoia Version 15.2 Beta (24C5089c)

Hello, our application works with Core Data to save some datas about its activity. We have background Tasks implemented and our app execution in background shows this error message in the Logs: error: Failed to acquire background task assertion for task 'CoreData: Executing write request'. Anyone could explain what this message means? Could it be that NSManagedObjectContext changes might not be written?

When the following models in SwiftData, @Model final class UndoRedoData { var id: [Int] init(id: [Int]) { self.id = id } } I created the following code. struct ContentView: View { @ObservedObject var swiftDataViewModel = SwiftDataArrayViewModel.shared @State private var idArray: [Int] = [1,2,3,4] @State private var firstviewSwich: Bool = true @State private var twoviewSwich: Bool = false @State private var threeviewSwich: Bool = false var body: some View { VStack { if firstviewSwich == true { Button(action: addItem) { Text("1.New Item") } } if twoviewSwich == true { Button { forArrayData() } label: { Text("2.Data Road") } } if threeviewSwich == true { Button(action: undoItem) { Text("3.Undo") } } } } private func addItem() { withAnimation { let newItem = UndoRedoData(id: [1,2,3,4]) swiftDataViewModel.taskContext.insert(newItem) do { try swiftDataViewModel.taskContext.save() } catch { print(error) } swiftDataViewModel.fetchItems() firstviewSwich.toggle() twoviewSwich.toggle() } } private func forArrayData() { twoviewSwich.toggle() for data in idArray { swiftDataViewModel.idUndoCreate(id: data, undoManager: swiftDataViewModel.arrayItemUndoManager) } threeviewSwich.toggle() } private func undoItem() { swiftDataViewModel.arrayItemUndoManager.undo() threeviewSwich.toggle() firstviewSwich.toggle() } } class SwiftDataArrayViewModel: ObservableObject { static let shared = SwiftDataArrayViewModel() let modelContainer: ModelContainer @ObservationIgnored lazy var taskContext: ModelContext = { return ModelContext(modelContainer) }() @Published var arrayItems = [UndoRedoData]() @Published var arrayItemUndoManager = UndoManager() init() { let schema = Schema([UndoRedoData.self]) let modelConfiguration = ModelConfiguration(schema: schema, isStoredInMemoryOnly: false) do { modelContainer = try ModelContainer(for: schema, configurations: [modelConfiguration]) } catch { fatalError(error) } fetchItems() } func fetchItems() { let fetchDescriptor = FetchDescriptor<UndoRedoData>() do { arrayItems = try taskContext.fetch(fetchDescriptor) } catch { fatalError(error) } } func idUndoCreate(id: Int, undoManager: UndoManager?) { undoManager?.registerUndo(withTarget: self) { target in target.removeID() } } func removeID() { if let firstUndoRedoData = arrayItems.first { print("Before Delete:\(firstUndoRedoData.id)") if !firstUndoRedoData.id.isEmpty { firstUndoRedoData.id.removeLast() } print("After Delete:\(firstUndoRedoData.id)") } do { try taskContext.save() } catch { print(error) } fetchItems() } } In this code, 1. Create an Item in New Item, 2. Execute Data Road and register the data in the array that is the same value as the data created in New Item in SwiftData one by one in UndoManager by for data in idArray. This is done because the data in the array and the data created by New Item in SwiftData can be known in advance. private func forArrayData() { twoviewSwich.toggle() for data in idArray { swiftDataViewModel.idUndoCreate(id: data, undoManager: swiftDataViewModel.arrayItemUndoManager) } // class SwiftDataArrayViewModel: ObservableObject func idUndoCreate(id: Int, undoManager: UndoManager?) { undoManager?.registerUndo(withTarget: self) { target in target.removeID() } } After registering in UndoManager, when Undo is executed with 3. Undo, instead of being able to perform Undo where one id is deleted each time, all the data of the id in SwiftData is deleted in a one-time Undo. I would like to be able to delete one id each time Undo is performed and restore them in sequence, but I can only delete them all once. Does this mean that such registration to UndoManager should not be done with for statements, etc.? Or is there another problem in the code? I want to make sure that one id is deleted for each Undo executed.

I have this actor actor ConcurrentDatabase: ModelActor { nonisolated let modelExecutor: any ModelExecutor nonisolated let modelContainer: ModelContainer init(modelContainer: ModelContainer) { self.modelExecutor = DefaultSerialModelExecutor(modelContext: ModelContext(modelContainer)) self.modelContainer = modelContainer } /// Save pending changes in the model context. private func save() { if self.modelContext.hasChanges { do { try self.modelContext.save() } catch { ... } } } } I am getting a runtime crash on: try self.modelContext.save() when trying to insert something into the database and save Thread 1: Fatal error: Incorrect actor executor assumption; Expected same executor as MainActor. Can anyone explain why this is happening?

Hi! I believe there might be a small bug in the SwiftData Quakes Sample App.^1 The Quakes app requests a JSON feed from USGS.^2 What seems to be breaking is that apparently earthquake entities from USGS can return with null magnitudes. That is throwing errors from the decoder: struct GeoFeatureCollection: Decodable { let features: [Feature] struct Feature: Decodable { let properties: Properties let geometry: Geometry struct Properties: Decodable { let mag: Double let place: String let time: Date let code: String } struct Geometry: Decodable { let coordinates: [Double] } } } which is expecting mag to not be nil. Here is my workaround: struct GeoFeatureCollection: Decodable { let features: [Feature] struct Feature: Decodable { let properties: Properties let geometry: Geometry struct Properties: Decodable { let mag: Double? let place: String let time: Date let code: String } struct Geometry: Decodable { let coordinates: [Double] } } } And then: extension Quake { /// Creates a new quake instance from a decoded feature. convenience init(from feature: GeoFeatureCollection.Feature) { self.init( code: feature.properties.code, magnitude: feature.properties.mag ?? 0.0, time: feature.properties.time, name: feature.properties.place, longitude: feature.geometry.coordinates[0], latitude: feature.geometry.coordinates[1] ) } }

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 }