After Xcode 26.1 was updated and installing the OS 26.1 simulators, my app started crashing related to transformable properties. When I checked my schema, I noticed that properties with array collection types are suddenly set with an option transformable with Optional("NSSecureUnarchiveFromData")], even though I do not use any transformable types. I verified the macros, no transformable was specified. This is causing ModelCoders to encode/decode my properties incorrectly. This is not an issue when I switch back to OS 26.0 simulators.

This simple test fails in my project. Similar code in my application also crashes. How do I debug the problem? What project settings are required. I have added SwiftData as a framework to test (and application) targets? Thanks, The problem is with: modelContext.insert(item) Thread 1: EXC_BAD_INSTRUCTION (code=EXC_I386_INVOP, subcode=0x0) import XCTest import SwiftData @Model class FakeModel { var name: String init(name: String) { self.name = name } } @MainActor final class FakeModelTests: XCTestCase { var modelContext: ModelContext! override func setUp() { super.setUp() do { let container = try ModelContainer(for: FakeModel.self, configurations: ModelConfiguration(isStoredInMemoryOnly: true)) modelContext = container.mainContext } catch { XCTFail("Failed to create ModelContainer: \(error)") modelContext = nil } } func testSaveFetchDeleteFakeItem() { guard let modelContext = modelContext else { XCTFail("ModelContext must be initialized") return } let item = FakeModel(name: "Test") modelContext.insert(item) let fetchDescriptor = FetchDescriptor<FakeModel>() let items = try! modelContext.fetch(fetchDescriptor) XCTAssertEqual(items.count, 1) XCTAssertEqual(items.first?.name, "Test") modelContext.delete(item) let itemsAfterDelete = try! modelContext.fetch(fetchDescriptor) XCTAssertEqual(itemsAfterDelete.count, 0) } }

Hello, I recently published an app that uses Swift Data as its primary data storage. The app uses concurrency, background threads, async await, and BLE communication. Sadly, I see my app incurs many fringe crashes, involving EXC_BAD_ACCESS, KERN_INVALID_ADDRESS, EXC_BREAKPOINT, etc. I followed these guidelines: One ModelContainer that is stored as a global variable and used throughout. ModelContexts are created separately for each task, changes are saved manually, and models are not passed around. Threads with different ModelContexts might manipulate and/or read the same data simultaneously. I was under the impression this meets the usage requirements. I suspect perhaps the issue lies in my usage of contexts in a single await function, that might be paused and resumed on a different thread (although same execution path). Is that the case? If so, how should SwiftData be used in async scopes? Is there anything else particularly wrong in my approach?

I have an image field on a Core Data entity with "Allows External Storage" enabled. When I delete a record, the external binary data file remains on disk. How can I ensure that all externally stored data is deleted along with the record?

Hello, I have an asset pack that I'm use to periodically distribute a sqlite database thats being used to an NSPersistentStore. Because the database is over a few GBs, and the files in an AssetPack are not mutable, I have to stream the database into a temporary file, then replace my NSPersistentStore. This requires that the user has 3x the storage available of the database, and permanently uses twice to storage needed. I'd like: To be able to mark a URL/File to be accessible for read/write access To be able to mark a file / URL as consumed when it's no needed. So that it can be cleared from the user storage while still maintaining an active subscription to the asset pack for updates. Thank you

Hi everyone! I have an app on the App Store that uses Core Data as its data store. (It's called Count on Me: Tally Counter. Feel free to check it out.) One of the app's core feature is an interactive widget with a simple button. When the button is tapped, it's supposed to update the entity in the store. My requirement is that the changes are then reflected with minimal latency in the main app and – ideally – also on other devices of the same iCloud user. And vice-versa: When an entity is updated in the app (or on another device where the same iCloud user is logged in), the widget that shows this entity should also refresh to reflect the changes. I have read multiple articles, downloaded sample projects, searched Stackoverflow and the Apple developer forums, and tried to squeeze a solution out of AI, but couldn't figure out how to make this work reliably. So I tried to reduce the core problem to a minimal example project. It has two issues that I cannot resolve: When I update an entity in the app, the widget is immediately updated as intended (due to a call to WidgetCenter's reloadAllTimelines method). However, when I update the same entity from the interactive widget using the same app intent, the changes are not reflected in the main app. For the widget and the app to use the same local data store, I need to enable App Groups in both targets and set a custom location for the store within the shared app group. So I specify a custom URL for the NSPersistentStoreDescription when setting up the Core Data stack. The moment I do this, iCloud sync breaks. Issue no. 1 is far more important to me as I haven't officially enabled iCloud sync yet in my real app that's already on the App Store. But it would be wonderful to resolve issue no. 2 as well. Surely, there must be a way to synchronize changes to the source of truth triggered by interactive widget with other devices of the same iCloud user. Otherwise, the feature to talk to the main app and the feature to synchronize with iCloud would be mutually exclusive. Some other developers I talked to have suggested that the widget should only communicate proposed changes to the main app and once the main app is opened, it processes these changes and writes them to the NSPersistentCloudKitContainer which then synchronizes across devices. This is not an option for me as it would result in a stale state and potential data conflicts with different devices. For example, when a user has the same widget on their iPhone and their iPad, taps a button on the iPhone widget, that change would not be reflected on the iPad widget until the user decides to open the app on the iPhone. At the same time, the user could tap the button multiple times on their iPad widget, resulting in a conflicting state on both devices. Thus, this approach is not a viable solution. An answer to this question will be greatly appreciated. The whole code including the setup of the Core Data stack is included in the repository reference above. Thank you!

Hello, From the documentation linked below, the limitations for Background Assets are the following: Size Limit: 200 GB Asset Pack Count: 100 I'm expecting I will need ~175 Asset Packs and around 500GB of storage. I understand Background Assets is a new, but is there a process or a potential that these limits will be increased in the future? Or is there a way to request an increase? I've tried contacting Apple Support as this is more of an Admin issue, however they've directed me here. Case ID 102725356578 https://developer.apple.com/help/app-store-connect/reference/apple-hosted-asset-pack-size-limits Thank you, Tanner

I have a simple app that makes an HTTPS call to gather some JSON which I then parse and add to my SwiftData database. The app then uses a simple @Query in a view to get the data into a list. on iOS 16 this works fine. No problems. But the same code on iOS 26 (targeting iOS 18.5) crashes after about 15 seconds of idle time after the list is populated. The error message is: Could not cast value of type '__NSCFNumber' (0x1f31ee568) to 'NSString' (0x1f31ec718). and occurs when trying to access ANY property of the list. I have a stripped down version of the app that shows the crash available. To replicate the issue: open the project in Xcode 26 target any iOS 26 device or simulator compile and run the project. after the list is displayed, wait about 15 seconds and the app crashes. It is also of note that if you try to run the app again, it will crash immediately, unless you delete the app from the device. Any help on this would be appreciated. Feedback number FB20295815 includes .zip file Below is the basic code (without the data models) The Best Seller List.Swift import SwiftUI import SwiftData @main struct Best_Seller_ListApp: App { var body: some Scene { WindowGroup { ContentView() } .modelContainer (for: NYTOverviewResponse.self) } } ContentView.Swift import os.log import SwiftUI struct ContentView: View { @Environment(\.modelContext) var modelContext @State private var listEncodedName = String() var body: some View { NavigationStack () { ListsView() } .task { await getBestSellerLists() } } func getBestSellerLists() async { guard let url = URL(string: "https://api.nytimes.com/svc/books/v3/lists/overview.json?api-key=\(NYT_API_KEY)") else { Logger.errorLog.error("Invalid URL") return } do { let decoder = JSONDecoder() var decodedResponse = NYTOverviewResponse() //decode the JSON let (data, _) = try await URLSession.shared.data(from: url) decoder.keyDecodingStrategy = .convertFromSnakeCase decodedResponse = try decoder.decode(NYTOverviewResponse.self, from: data) //remove any lists that don't have list_name_encoded. Fixes a bug in the data decodedResponse.results!.lists = decodedResponse.results!.lists!.filter { $0.listNameEncoded != "" } // sort the lists decodedResponse.results!.lists!.sort { (lhs, rhs) -> Bool in lhs.displayName < rhs.displayName } //delete any potential existing data try modelContext.delete(model: NYTOverviewResponse.self) //add the new data modelContext.insert(decodedResponse) } catch { Logger.errorLog.error("\(error.localizedDescription)") } } } ListsView.Swift import os.log import SwiftData import SwiftUI @MainActor struct ListsView: View { //MARK: - Variables and Constants @Query var nytOverviewResponses: [NYTOverviewResponse] enum Updated: String { case weekly = "WEEKLY" case monthly = "MONTHLY" } //MARK: - Main View var body: some View { List { if nytOverviewResponses.isEmpty { ContentUnavailableView("No lists yet", systemImage: "list.bullet", description: Text("NYT Bestseller lists not downloaded yet")) } else { WeeklySection MonthlySection } } .navigationBarTitle("Bestseller Lists", displayMode: .large) .listStyle(.grouped) } var WeeklySection: some View { let rawLists = nytOverviewResponses.last?.results?.lists ?? [] // Build a value-typed array to avoid SwiftData faulting during sort let weekly = rawLists .filter { $0.updateFrequency == Updated.weekly.rawValue } .map { (name: $0.displayName, encoded: $0.listNameEncoded, model: $0) } .sorted { $0.name < $1.name } return Section(header: Text("Weekly lists to be published on \(nytOverviewResponses.last?.results?.publishedDate ?? "-")")) { ForEach(weekly, id: \.encoded) { item in Text(item.name).font(Font.custom("Georgia", size: 17)) } } } var MonthlySection: some View { let rawLists = nytOverviewResponses.last?.results?.lists ?? [] // Build a value-typed array to avoid SwiftData faulting during sort let monthly = rawLists .filter { $0.updateFrequency == Updated.monthly.rawValue } .map { (name: $0.displayName, encoded: $0.listNameEncoded, model: $0) } .sorted { $0.name < $1.name } return Section(header: Text("Monthly lists to be published on \(nytOverviewResponses.last?.results?.publishedDate ?? "-")")) { ForEach(monthly, id: \.encoded) { item in Text(item.name).font(Font.custom("Georgia", size: 17)) } } } }

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 } }

Exact same app works fine in debug builds, but on release builds I see this stacktrace indicating that assert() was hit. Incident Identifier: *** Distributor ID: com.apple.TestFlight Hardware Model: iPhone14,3 Process: AuditOS [67847] Path: /private/var/containers/Bundle/Application/*** Identifier: *** Version: 1.0 (15) AppStoreTools: 16C5031b AppVariant: 1:iPhone14,3:18 Beta: YES Code Type: ARM-64 (Native) Role: Foreground Parent Process: launchd [1] Coalition: *** Date/Time: 2025-02-11 12:37:54.7801 -0600 Launch Time: 2025-02-11 12:37:33.1737 -0600 OS Version: iPhone OS 18.3 (22D63) Release Type: User Baseband Version: 4.20.03 Report Version: 104 Exception Type: EXC_BREAKPOINT (SIGTRAP) Exception Codes: 0x0000000000000001, 0x000000019d388e2c Termination Reason: SIGNAL 5 Trace/BPT trap: 5 Terminating Process: exc handler [67847] Triggered by Thread: 0 Thread 0 Crashed: 0 libswiftCore.dylib 0x000000019d388e2c _assertionFailure(_:_:file:line:flags:) + 264 (AssertCommon.swift:147) 1 SwiftData 0x0000000261842e04 Schema.KeyPathCache.validateAndCache(keypath:on:) + 2628 (Schema.swift:0) 2 SwiftData 0x000000026178cac4 static PersistentModel.keyPathToString(keypath:) + 360 (DataUtilities.swift:36) 3 SwiftData 0x000000026184c9e4 static PersistentModel.fetchDescriptorKeyPathString(for:) + 36 (FetchDescriptor.swift:51) 4 SwiftData 0x00000002617b9770 closure #1 in PredicateExpressions.KeyPath.convert(state:) + 172 (FetchDescriptor.swift:458) 5 SwiftData 0x00000002617b7f48 PredicateExpressions.KeyPath.convert(state:) + 352 (FetchDescriptor.swift:438) 6 SwiftData 0x00000002617bb7ec protocol witness for ConvertibleExpression.convert(state:) in conformance PredicateExpressions.KeyPath&lt;A, B&gt; + 16 (&lt;compiler-generated&gt;:0) 7 SwiftData 0x00000002617baaa0 PredicateExpression.convertToExpressionOrPredicate(state:) + 716 (FetchDescriptor.swift:219) 8 SwiftData 0x00000002617ba6dc PredicateExpression.convertToExpression(state:) + 32 (FetchDescriptor.swift:237) 9 SwiftData 0x00000002617b7cfc PredicateExpressions.Equal.convert(state:) + 328 (:-1) 10 SwiftData 0x00000002617bba08 protocol witness for ConvertibleExpression.convert(state:) in conformance PredicateExpressions.Equal&lt;A, B&gt; + 64 (&lt;compiler-generated&gt;:0) 11 SwiftData 0x00000002617baaa0 PredicateExpression.convertToExpressionOrPredicate(state:) + 716 (FetchDescriptor.swift:219) 12 SwiftData 0x00000002617b7abc PredicateExpression.convertToPredicate(state:) + 28 (FetchDescriptor.swift:244) 13 SwiftData 0x00000002617b7190 nsFetchRequest&lt;A&gt;(for:in:) + 1204 (FetchDescriptor.swift:64) 14 SwiftData 0x0000000261783358 DefaultStore.fetch&lt;A&gt;(_:) + 292 (DefaultStore.swift:496) 15 SwiftData 0x000000026178322c protocol witness for DataStore.fetch&lt;A&gt;(_:) in conformance DefaultStore + 16 (&lt;compiler-generated&gt;:0) 16 SwiftData 0x00000002617847fc asDataStore #1 &lt;A&gt;&lt;A1&gt;(_:) in closure #1 in ModelContext.fetch&lt;A&gt;(_:) + 3152 (ModelContext.swift:2590) 17 SwiftData 0x00000002617a74d8 partial apply for closure #1 in ModelContext.fetch&lt;A&gt;(_:) + 100 (&lt;compiler-generated&gt;:0) 18 SwiftData 0x00000002617a7438 closure #1 in ModelContext.enumerateFetchableStores&lt;A&gt;(_:_:) + 208 (ModelContext.swift:2527) 19 SwiftData 0x00000002617a731c specialized ModelContext.enumerateFetchableStores&lt;A&gt;(_:_:) + 200 (ModelContext.swift:2522) 20 SwiftData 0x00000002617a6f08 ModelContext.fetch&lt;A&gt;(_:) + 144 (ModelContext.swift:2534) 21 SwiftData 0x00000002617a6e70 dispatch thunk of ModelContext.fetch&lt;A&gt;(_:) + 56 (:-1) 22 AuditOS 0x00000001041af3f4 0x10419c000 + 78836 23 AuditOS 0x00000001041bebd5 0x10419c000 + 142293 24 AuditOS 0x00000001041bbbf5 0x10419c000 + 130037 25 AuditOS 0x00000001041d8be5 0x10419c000 + 248805 26 AuditOS 0x00000001041bde6d 0x10419c000 + 138861 27 libswift_Concurrency.dylib 0x00000001aa6bfe39 completeTaskWithClosure(swift::AsyncContext*, swift::SwiftError*) + 1 (Task.cpp:497) The code in question looks like this: func addRecord&lt;T: MyDtoProtocol&gt;(_ someDTO: T) async throws { var zone: ZoneModel? = nil let recordName = someDTO.recordNameType let fetchDescriptor = FetchDescriptor&lt;T.ModelType&gt; (predicate: #Predicate {$0.recordName == recordName}) &gt; var localEntitites: [T.ModelType] = try modelContext.fetch(fetchDescriptor) &lt;---- I have isolated crash to this line. Basically for each swiftdata model type I have associatedType for Data Transfer Object type and vice versa.

Hello everyone, I'm trying to adopt the new Staged Migrations for Core Data and I keep running into an error that I haven't been able to resolve. The error messages are as follows: warning: Multiple NSEntityDescriptions claim the NSManagedObject subclass 'Movie' so +entity is unable to disambiguate. warning: 'Movie' (0x60000350d6b0) from NSManagedObjectModel (0x60000213a8a0) claims 'Movie'. error: +[Movie entity] Failed to find a unique match for an NSEntityDescription to a managed object subclass This happens for all of my entities when they are added/fetched. Movie is an abstract entity subclass, and it has the error error: +[Movie entity] Failed to find which is unique to the subclass entities, but this occurs for all entities. The NSPersistentContainer is loaded only once, and I set the following option after it's loaded: storeDescription.setOption( [stages], forKey: NSPersistentStoreStagedMigrationManagerOptionKey ) The warnings and errors only appear after I fetch or save to context. It happens regardless of whether the database was migrated or not. In my test project, using the generic NSManagedObject with NSEntityDescription.insertNewObject(forEntityName: "MyEntity", into: context) does not cause the issue. However, using the generic NSManagedObject is not a viable option for my app. Setting the module to "Current Project Module" doesn't change anything, except that it now prints "claims 'MyModule.Show'" in the warnings. I have verified that there are no other entities with the same name or renameIdentifier. Has anyone else encountered this issue, or can offer any suggestions on how to resolve it? Thanks in advance for any help!

I built a SwiftData App that relies on CloudKit to synchronize data across devices. That means all model relationships must be expressed as Optional. That’s fine, but there is a limitation in using Optional’s in SwiftData SortDescriptors (Crashes App) That means I can’t apply a SortDescriptor to ModelA using some property value in ModelB (even if ModelB must exist) I tried using a computed property in ModelA that referred to the property in ModelB, BUT THIS DOESN”T WORK EITHER! Am I stuck storing redundant data In ModelA just to sort ModelA as I would like???

I have made a Swift App for MacOS 15 under XCode 16.3, which runs fine. I also want to run it under the previous MacOS 14. Unfortunately it crashes without even starting up (it does not even reach the first log output statement on the first view) The crash reason is Crashed Thread: 0 Dispatch queue: com.apple.main-thread Exception Type: EXC_BAD_INSTRUCTION (SIGILL) Exception Codes: 0x0000000000000001, 0x0000000000000000 Termination Reason: Namespace SIGNAL, Code 4 Illegal instruction: 4 Terminating Process: exc handler [2970] I have set the miminium deployment to MacOS 14.0 but to no effect. The XCode machine is a MacOS 15.4 on Arm M3 and the target machine is MacOS 14.7.5 on Intel (MacBook Air) I think it might be related to the compiler and linker settings.

Environment visionOS 26 Xcode 26 Issue I am experiencing crash when trying to access a [String] from a @Model data, after dismissing an immersiveSpace and opening a WindowGroup. This crash only occurs when trying to access the [String] property of my Model. It works fine with other properties. Thread 1: Fatal error: This backing data was detached from a context without resolving attribute faults: PersistentIdentifier(...) Steps to Reproduce Open WindowGroup Dismiss window, open ImmersiveSpace Dismiss ImmersiveSpace, reopen WindowGroup Any guidance would be appreciated! @main struct MyApp: App { var body: some Scene { WindowGroup(id: "main") { ContentView() } .modelContainer(for: [Item.self]) ImmersiveSpace(id: "immersive") { ImmersiveView() } } } // In SwiftData model @Model class Item { var title: String = "" // Accessing this property works fine var tags: [String] = [] @storageRestrictions(accesses: _$backingData, initializes: _tags) init(initialValue) { _$backingData.setValue(forKey: \. tags, to: initialValue) _tags =_ SwiftDataNoType() } get { _$observationRegistrar.access(self, keyPath: \.tags) **return self getValue(forkey: \.tags)** // Crashes here }

I would like to have a SwiftData predicate that filters against an array of PersistentIdentifiers. A trivial use case could filtering Posts by one or more Categories. This sounds like something that must be trivial to do. When doing the following, however: let categoryIds: [PersistentIdentifier] = categoryFilter.map { $0.id } let pred = #Predicate<Post> { if let catId = $0.category?.persistentModelID { return categoryIds.contains(catId) } else { return false } } The code compiles, but produces the following runtime exception (XCode 26 beta, iOS 26 simulator): 'NSInvalidArgumentException', reason: 'unimplemented SQL generation for predicate : (TERNARY(item != nil, item, nil) IN {}) (bad LHS)' Strangely, the same code works if the array to filter against is an array of a primitive type, e.g. String or Int. What is going wrong here and what could be a possible workaround?

Perhaps I just have the wrong expectations, but I discovered some odd behavior from SwiftData that sure seems like a bug to me... If you make any change to any SwiftData model object — even just setting a property to its current value — every SwiftUI view that uses SwiftData is rebuilt. Every query and every entity reference, even if the property was set on a model class that is completely unrelated to the view. SwiftUI does such a good job of optimizing UI updates that it's hard to notice the issue. I only noticed it because the updates were triggering my debug print statements. To double-check this, I went back to Apple's new iOS app template — the one that is just a list of dated items — and added a little code to touch an unrelated record in the background: @Model class UnrelatedItem { var name: String init(name: String) { self.name = name } } @main struct jumpyApp: App { var sharedModelContainer: ModelContainer = { let schema = Schema([ Item.self, UnrelatedItem.self ]) let modelConfiguration = ModelConfiguration(schema: schema, isStoredInMemoryOnly: false) do { return try ModelContainer(for: schema, configurations: [modelConfiguration]) } catch { fatalError("Could not create ModelContainer: \(error)") } }() init() { let context = sharedModelContainer.mainContext // Create 3 items at launch so we immediately have some data to work with. if try! context.fetchCount(FetchDescriptor<Item>()) == 0 { for _ in 0..<3 { let item = Item(timestamp: Date()) context.insert(item) } } // Now create one unrelated item. let unrelatedItem = UnrelatedItem(name: "Mongoose") context.insert(unrelatedItem) try? context.save() // Set up a background task that updates the unrelated item every second. Task { while true { try? await Task.sleep(nanoseconds: 1_000_000_000) Task { @MainActor in // We don't even have to change the name or save the contxt. // Just setting the name to the same value will trigger a change. unrelatedItem.name = "Mongoose" } } } } var body: some Scene { WindowGroup { ContentView() } .modelContainer(sharedModelContainer) } } I also added a print statement to the ContentView so I could see when the view updates. struct ContentView: View { @Environment(\.modelContext) private var modelContext @Query private var items: [Item] var body: some View { NavigationSplitView { List { let _ = Self._printChanges() ... The result is that the print statement logs 2 messages to the debug console every second. I checked in iOS 17, 18.1, and 18.2, and they all behave this way. Is this the intended behavior? I thought the whole point of the new Observation framework in iOS 17 was to track which data had changed and only send change notifications to observers who were using that data.

I'm experiencing a crash during a lightweight Core Data migration when a widget that accesses the same database is installed. The migration fails with the following error: CoreData: error: addPersistentStoreWithType:configuration:URL:options:error: returned error NSCocoaErrorDomain (134100) error: userInfo: CoreData: error: userInfo: error: metadata : { NSPersistenceFrameworkVersion = 1414; NSStoreModelVersionChecksumKey = "dY78fBnnOm7gYtb+QT14GVGuEmVlvFSYrb9lWAOMCTs="; NSStoreModelVersionHashes = { Entity1 = { ... }; Entity2 = { ... }; Entity3 = { ... }; Entity4 = { ... }; Entity5 = { ... }; }; NSStoreModelVersionHashesDigest = "aOalpc6zSzr/VpduXuWLT8MLQFxSY4kHlBo/nuX0TVQ/EZ+MJ8ye76KYeSfmZStM38VkyeyiIPf4XHQTMZiH5g=="; NSStoreModelVersionHashesVersion = 3; NSStoreModelVersionIdentifiers = ( "" ); NSStoreType = SQLite; NSStoreUUID = "9AAA7AB7-18D4-4DE4-9B54-893D08FA7FC4"; "_NSAutoVacuumLevel" = 2; } The issue occurs only when the widget is installed. If I remove the widget’s access to the Core Data store, the migration completes successfully. The crash happens only once—after the app is restarted, everything works fine. This occurs even though I'm using lightweight migration, which should not require manual intervention. My suspicion is that simultaneous access to the Core Data store by both the main app and the widget during migration might be causing the issue. Has anyone encountered a similar issue? Is there a recommended way to ensure safe migration while still allowing the widget to access Core Data? Any insights or recommendations would be greatly appreciated.

Hi guys. Can someone please confirm this bug so I report it? The issue is that SwiftData relationships don't update the views in some specific situations on devices running iOS 18 Beta. One clear example is with CloudKit. I created a small example for testing. The following code creates two @models, one to store bands and another to store their records. The following code works with no issues. (You need to connect to a CloudKit container and test it on two devices) import SwiftUI import SwiftData struct ContentView: View { @Environment(\.modelContext) private var modelContext @Query private var records: [Record] var body: some View { NavigationStack { List(records) { record in VStack(alignment: .leading) { Text(record.title) Text(record.band?.name ?? "Undefined") } } .toolbar { ToolbarItem { Button("Add Record") { let randomNumber = Int.random(in: 1...100) let newBand = Band(name: "New Band \(randomNumber)", records: nil) modelContext.insert(newBand) let newRecord = Record(title: "New Record \(randomNumber)", band: newBand) modelContext.insert(newRecord) } } } } } } @Model final class Record { var title: String = "" var band: Band? init(title: String, band: Band?) { self.title = title self.band = band } } @Model final class Band { var name: String = "" var records: [Record]? init(name: String, records: [Record]?) { self.name = name self.records = records } } This view includes a button at the top to add a new record associated with a new band. The data appears on both devices, but if you include more views inside the List, the views on the second device are not updated to show the values of the relationships. For example, if you extract the row to a separate view, the second device shows the relationships as "Undefined". You can try the following code. struct ContentView: View { @Environment(\.modelContext) private var modelContext @Query private var records: [Record] var body: some View { NavigationStack { List { ForEach(records) { record in RecordRow(record: record) } } .toolbar { ToolbarItem { Button("Add Record") { let randomNumber = Int.random(in: 1...100) let newBand = Band(name: "New Band \(randomNumber)", records: nil) modelContext.insert(newBand) let newRecord = Record(title: "New Record \(randomNumber)", band: newBand) modelContext.insert(newRecord) } } } } } } struct RecordRow: View { let record: Record var body: some View { VStack(alignment: .leading) { Text(record.title) Text(record.band?.name ?? "Undefined") } } } Here I use a ForEach loop and move the row to a separate view. Now on the second device the relationships are nil, so the row shows the text "Undefined" instead of the name of the band. I attached an image from my iPad. I inserted all the information on my iPhone. The first three rows were inserted with the first view. But the last two rows were inserted after I extracted the rows to a separate view. Here you can see that the relationships are nil and therefore shown as "Undefined". The views are not updated to show the real value of the relationship. This example shows the issue with CloudKit, but this also happens locally in some situations. The system doesn't detect updates in relationships and therefore doesn't refresh the views. Please, let me know if you can reproduce the issue. I'm using Mac Sequoia 15.1, and two devices with iOS 18.0.

I have a simple app that uses SwiftUI and SwiftData to maintain a database. The app runs on multiple iPhones and iPads and correctly synchronises across those platforms. So I am correct setting Background Modes and Remote Notifications. I have also correctly setup my Model Configuration and ModelContainer (Otherwise I would expect syncing to fail completely). The problem arises when I run on a Mac (M1 or M3) either using Mac Designed for iPad or Mac Catalyst. This can be debugging in Xcode or running the built app. Then the app does not reflect changes made in the iPhone or iPad apps unless I follow a specific sequence. Leave the app, (e.g click on a Finder window), then come back to the app (i.e click on the app again). Now the app will show the changes made on the iPhone/iPad. It looks like the app on the Mac is not processing remote notifications when in the background - it only performs them when the app has just become active. It also looks like the Mac is not performing these sync operations when the app is active. I have tried waiting 30 minutes and still the sync doesn't happen unless I leave the app and come back to it. I am using the same development CloudKit container in all cases

Hi all, has anybody found the trick how to get SwiftData working with SpotLight Search? Setting the attribute "spotlight" in the Model definition seems to do nothing at all, as pointed out by Paul Hudson in his new book as well (https://www.hackingwithswift.com/quick-start/swiftdata/how-to-index-swiftdata-objects-in-spotlight) Thanks a lot!