I tried to use the .deny deleteRule but it seems to have no effect. The toolbar button adds an item with a relationship to a category to the context. Swiping on the category deletes the category even though an item is referencing the category. There is also no error thrown when saving the context. It is as if the deleteRule was not there. For other deleteRules like .cascade, the provided sample code works as expected. import SwiftUI import SwiftData @Model class Category { var name: String @Relationship(deleteRule: .deny) var items: [Item] = [] init(name: String) { self.name = name } } @Model class Item { var name: String var category: Category? init(name: String, category: Category) { self.name = name self.category = category } } struct DenyDeleteRule: View { @Environment(\.modelContext) private var modelContext @Query private var categories: [Category] @Query private var items: [Item] var body: some View { List { Section("Items") { ForEach(items) { item in Text(item.name) } } Section("Categories") { ForEach(categories) { category in VStack(alignment: .leading) { Text(category.name).bold() ForEach(category.items) { item in Text("• \(item.name)") } } } .onDelete(perform: deleteCategory) } } .toolbar { Button("Add Sample") { let category = Category(name: "Sample") let item = Item(name: "Test Item", category: category) modelContext.insert(item) } } } func deleteCategory(at offsets: IndexSet) { for index in offsets { let category = categories[index] modelContext.delete(category) do { try modelContext.save() } catch { print(error) } } } } #Preview { NavigationStack { DenyDeleteRule() } .modelContainer(for: [Item.self, Category.self], inMemory: true) }

I have an iOS app using SwiftData with VersionedSchema. The schema is synchronized with an CloudKit container. I previously introduced some model properties that I have now removed, as they are no longer needed. This results in the current schema version being identical to one of the previous ones (except for its version number). This results in the following exception: 'NSInvalidArgumentException', reason: 'Duplicate version checksums across stages detected.' So it looks like we cannot have a newer schema version with an identical content to an older schema version. The intuitive way would be to re-add the old (identical) schema version to the end of the "schemas" list property in the SchemaMigrationPlan, in order to signal that it is the newest one, and to add a migration stage back to it, thus: public enum MySchemaMigrationPlan: SchemaMigrationPlan { public static var schemas: [any VersionedSchema.Type] { [ SchemaV100.self, SchemaV101.self, SchemaV100.self ] } public static var stages: [MigrationStage] { [ migrateV100toV101, migrateV101toV100 ] } However, I am not sure if this is the right way to go, as previously, as I wanted to write unit tests for schema migration and rollback, I tried defining an inverse for each migration stage, so that I could trigger a migration and a rollback from a unit test, which resulted in an exception saying that it is not supported to downgrade a VersionedSchema. I must admit that I solved the original problem by introducing a dummy model property that I will later remove. What would have been the correct approach?

When I update a variable inside my model that is marked @Transient, my view does not update with this change. Is this normal? If I update a non-transient variable inside the model at the same time that I update the transient one, then both changes are propagated to my view. Here is an example of the model: @Model public class WaterData { public var target: Double = 3000 @Transient public var samples: [HKQuantitySample] = [] } Updating samples only does not propagate to my view.

If I set my build settings "default actor isolation" to MainActor, how do my @ModelActor actors and model classes need to look like ? For now, I am creating instances of my @ModelActor actors and passing my modelContext container and processing all data there. Everything stays in this context. No models are transferred back to MainActor. Now, after changing my project settings, I am getting a huge amount of warnings. Do I need to set all my model classes to non-isolated and the @ModelActor actor as well? Is there any new sample code to cover this topic ... did not find anything for now. Thanks in advance, Marc

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?

We are trying to solve for the following condition with SwiftData + CloudKit: Lots of data in CloudKit Perform "app-reset" to clear data & App settings and start fresh. Reset data models with try modelContext.delete(model:_) myModel.count() confirms local deletion (0 records); but iCloud Console shows expectedly slow process to delete. Old CloudKit data is returning during the On Boarding process. Questions: • Would making a new iCloud Zone for each reset work around this, as the new zone would be empty? We're having trouble finding details about how to do this with SwiftData. • Would CKSyncEngine have a benefit over the default SwiftData methods? Open to hearing if anyone has experienced a similar challenge and how you worked around it!

Hi, I am building an iOS app with SwiftUI and SwiftData for the first time and I am experiencing a lot of difficulty with this error: Thread 44: Fatal error: Never access a full future backing data - PersistentIdentifier(id: SwiftData.PersistentIdentifier.ID(backing: SwiftData.PersistentIdentifier.PersistentIdentifierBacking.managedObjectID(<ID> <x-coredata://<UUID>/MySwiftDataModel/p1>)), backing: SwiftData.PersistentIdentifier.PersistentIdentifierBacking.managedObjectID(<ID> <x-coredata://<UUID>/MySwiftDataModel/p1>)) with Optional(<UUID>) I have been trying to figure out what the problem is, but unfortunately I cannot find any information in the documentation or on other sources online. My only theory about this error is that it is somehow related to fetching an entity that has been created in-memory, but not yet saved to the modelContext in SwiftData. However, when I am trying to debug this, it's not clear this is the case. Sometimes the error happens, sometimes it doesn't. Saving manually does not always solve the error. Therefore, it would be extremely helpful if someone could explain what this error means and whether there are any best practices to do with SwiftData, or some pitfalls to avoid (such as wrapping my model context into a repository class). To be clear, this problem is NOT related to one area of my code, it happens throughout my app, at unpredictable places and time. Given that there is very little information related to this error, I am at a loss at how to make sure that this never happens. This question has been asked on the forum here as well as on StackOverflow, Reddit (can't link that here), but none of the answers worked for me. For reference, my models generally look like this: import Foundation import SwiftData @Model final class MySwiftDataModel { // Stable cross-device identity @Attribute(.unique) var uuid: UUID var someNumber: Int var someString: String @Relationship(deleteRule: .nullify, inverse: \AnotherSwiftDataModel.parentModel) var childModels: [AnotherSwiftDataModel] init(uuid: UUID = UUID(), someNumber: Int = 1, someString: String = "Some", childModels: [AnotherSwiftDataModel] = []) { self.uuid = uuid self.someNumber = someNumber self.someString = someString self.childModels = childModels } func addChildModel(model: AnotherSwiftDataModel) { self.childModels.append(model) } func removeChildModel(by id: PersistentIdentifier) { self.childModels = self.childModels.filter { $0.id != id } } } and the child model: import Foundation import SwiftData @Model final class AnotherSwiftDataModel { // Stable cross-device identity @Attribute(.unique) var uuid: UUID var someNumber: Int var someString: String var parentModel: MySwiftDataModel? init(uuid: UUID = UUID(), someNumber: Int = 1, someString: String = "Some") { self.uuid = uuid self.someNumber = someNumber self.someString = someString } } For now, you can assume I am not using CloudKit - i know for a fact the error is unrelated to CloudKit, because it happens when I am not using CloudKit (so I do not need to follow CloudKit's requirements for model design, such as nullable values etc). As I said, the error surfaces at different times - sometimes during assignments, a lot of times during deletions of related models, etc. Could you please explain what I am doing wrong and how I can make sure that this error does not happen? What are the architectural patterns that work best for SwiftData in this case? Do you have any examples of things I should avoid? Thanks

I have encountered the following error and reduced my code to the minimum necessary to reliably reproduce this error. Fatal error: Duplicate keys of type 'AnyHashable2' were found in a >Dictionary. This usually means either that the type violates Hashable's >requirements, or that members of such a dictionary were mutated after insertion. It occurs when instances of a swiftdata model are inserted (the error occurs reliably when inserting five or more instances. Fewer insertions seems to make the error either more rare or go away entirely) and a Picker with .menu pickerStyle is present. Any of the following changes prevents the error from occuring: adding id = UUID() to the Item class removing .tag(item) in the picker content using any pickerStyle other than .menu using an observable class instead of a swiftdata class I would greatly appreciate if anyone knows what exactly is going on here. Tested using XCode Version 16.4 (16F6), iPhone 16 Pro iOS 18.5 Simulator and iPhone 15 Pro iOS 18.5 real device. import SwiftUI import SwiftData @Model class Item { var name: String init(name: String) { self.name = name } } struct DuplicateKeysErrorView: View { @Environment(\.modelContext) private var modelContext @Query(sort: \Item.name) private var items: [Item] @State var selection: Item? = nil var body: some View { List { Picker("Picker", selection: $selection) { Text("Nil").tag(nil as Item?) ForEach(items) { item in Text(item.name).tag(item) } } .pickerStyle(.menu) Button("Add 5 items") { modelContext.insert(Item(name: UUID().uuidString)) modelContext.insert(Item(name: UUID().uuidString)) modelContext.insert(Item(name: UUID().uuidString)) modelContext.insert(Item(name: UUID().uuidString)) modelContext.insert(Item(name: UUID().uuidString)) } } .onAppear { try! modelContext.delete(model: Item.self) } } } #Preview { DuplicateKeysErrorView() .modelContainer(for: Item.self) }

I have used core data before via the model editor. This is the first time I'm using swift data and that too with CloudKit. Can you tell me if the following model classes are correct? I have an expense which can have only one sub category which in turn belongs to a single category. Here are my classes... // Expense.swift // Pocket Expense Diary // // Created by Neerav Kothari on 16/05/25. // import Foundation import SwiftData @Model class Expense { @Attribute var expenseDate: Date? = nil @Attribute var expenseAmount: Double? = nil @Attribute var expenseCategory: Category? = nil @Attribute var expenseSubCategory: SubCategory? = nil var date: Date { get { return expenseDate ?? Date() } set { expenseDate = newValue } } var amount: Double{ get { return expenseAmount ?? 0.0 } set { expenseAmount = newValue } } var category: Category{ get { return expenseCategory ?? Category.init(name: "", icon: "") } set { expenseCategory = newValue } } var subCategory: SubCategory{ get { return expenseSubCategory ?? SubCategory.init(name: "", icon: "") } set { expenseSubCategory = newValue } } init(date: Date, amount: Double, category: Category, subCategory: SubCategory) { self.date = date self.amount = amount self.category = category self.subCategory = subCategory } } // // Category.swift // Pocket Expense Diary // // Created by Neerav Kothari on 16/05/25. // import Foundation import SwiftData @Model class Category { @Attribute var categoryName: String? = nil @Attribute var categoryIcon: String? = nil var name: String { get { return categoryName ?? "" } set { categoryName = newValue } } var icon: String { get { return categoryIcon ?? "" } set { categoryIcon = newValue } } @Relationship(inverse: \Expense.expenseCategory) var expenses: [Expense]? = [] init(name: String, icon: String) { self.name = name self.icon = icon } } // SubCategory.swift // Pocket Expense Diary // // Created by Neerav Kothari on 16/05/25. // import Foundation import SwiftData @Model class SubCategory { @Attribute var subCategoryName: String? = nil @Attribute var subCategoryIcon: String? = nil var name: String { get { return subCategoryName ?? "" } set { subCategoryName = newValue } } var icon: String { get { return subCategoryIcon ?? "" } set { subCategoryIcon = newValue } } @Relationship(inverse: \Expense.expenseSubCategory) var expenses: [Expense]? = [] init(name: String, icon: String) { self.name = name self.icon = icon } } The reason why I have wrappers is the let the existing code (before CloudKit was integrated), work. In future versions I plan to query expenses even via category or sub category. I particularly doubt for the relationship i have set. should there be one from category to subcategory as well?

Greetings i have an app that uses three different SwiftData models and i want to know what is the best way to use the them accross the app. I though a centralized behaviour and i want to know if it a correct approach.First let's suppose that the first view of the app will load the three models using the @Enviroment that work with @Observation. Then to other views that add data to the swiftModels again with the @Environment. Another View that will use the swiftData models with graph and datas for average and min and max.Is this a corrent way? or i should use @Query in every view that i want and ModelContext when i add the data. @Observable class CentralizedDataModels { var firstDataModel: [FirstDataModel] = [] var secondDataModel: [SecondDataModel] = [] var thirdDataModel: [ThirdDataModel] = [] let context: ModelContext init(context:ModelContext) { self.context = context } }

Hi, I am creating an app that can include videos or images in it's data. While @Attribute(.externalStorage) helps with images, with AVAssets I actually would like access to the URL behind that data. (as it would be stupid to load and then save the data again just to have a URL) One key component is to keep all of this clean enough so that I can use (private) CloudKit syncing with the resulting model. All the best Christoph

My project is using swiftData and I want to implement iCloud sync in it. Now, my data base doesnt have any optional attributes or relationships and CloudKit wants them to be optional. So, rather than editing all code with unwrapping code for the optionals, how can I provide a bridge that does so in the last stage of actually saving to the store? Sort of, capture it in a proxy object before writing and after reading from the store. Is there a neat way that can save a lot of debugging? I have code snippets from chat gpt and they are hard to debug. This is my first project in swiftUI. Thanks. Neerav

I have a strange crash which I have problems understanding. It only happens on a few devices, after a ModelContainer migration, and it doesn't seem to crash on the migration itself. The fetch is done in onAppear, and shouldn't necessarily result in a crash, as it is an optional try: let request = FetchDescriptor<Rifle>() let data = try? modelContext.fetch(request) if let data, !data.isEmpty { rifle = data.first(where: { $0.uuid.uuidString == settings.selectedRifleId }) ?? data.first! } When I get logs from users, there seems to be an error in encoding? Exception Type: EXC_BREAKPOINT (SIGTRAP) Exception Codes: 0x0000000000000001, 0x000000018e8bfd78 Termination Reason: SIGNAL 5 Trace/BPT trap: 5 Terminating Process: exc handler [71687] Triggered by Thread: 0 Thread 0 name: Dispatch queue: com.apple.main-thread Thread 0 Crashed: 0 libswiftCore.dylib 0x18e8bfd78 _assertionFailure(_:_:file:line:flags:) + 264 1 SwiftData 0x24e18b480 0x24e14c000 + 259200 2 SwiftData 0x24e193968 0x24e14c000 + 293224 3 SwiftData 0x24e195a78 0x24e14c000 + 301688 4 libswiftCore.dylib 0x18e8e4084 _KeyedEncodingContainerBox.encodeNil<A>(forKey:) + 352 5 libswiftCore.dylib 0x18e8d79f0 KeyedEncodingContainer.encodeNil(forKey:) + 64 6 SwiftData 0x24e19f09c 0x24e14c000 + 340124 7 SwiftData 0x24e1a3dec 0x24e14c000 + 359916 8 libswiftCore.dylib 0x18ec10be8 dispatch thunk of Encodable.encode(to:) + 32 9 SwiftData 0x24e1cd500 0x24e14c000 + 529664 10 SwiftData 0x24e1cd0c8 0x24e14c000 + 528584 11 SwiftData 0x24e1da960 0x24e14c000 + 584032 12 SwiftData 0x24e1ee2ec 0x24e14c000 + 664300 13 SwiftData 0x24e1d97d8 0x24e14c000 + 579544 14 SwiftData 0x24e1eada0 0x24e14c000 + 650656 15 SwiftData 0x24e1d989c 0x24e14c000 + 579740 16 SwiftData 0x24e1eee78 0x24e14c000 + 667256 17 Impact 0x1027403bc 0x10268c000 + 738236

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! 😊

Hi, I am developing a Screen Time App and I am having issues with the ShieldConfigurationExtension (ShieldConfigurationDataSource). I know this extensions is sandboxed but I should be able to read data from the main app. I am using SwiftData as my database, but I am unable to initialize it in the extensions with an error indicating insufficient file permissions. I have App Group set up and I am able to share data using UserDefaults but that is just inconvenient. Is there any way I could just open the SwiftData in read only mode so that I could display the user some info on the shield? SwiftData Init: private func setupContainer() throws { let schema = Schema([ DogEntity.self, HouseEntity.self ]) // Use app group container if available let config: ModelConfiguration if let containerURL = FileManager.default.containerURL( forSecurityApplicationGroupIdentifier: "group.\(Bundle.app.bundleIdentifier ?? "")" ) { config = ModelConfiguration(schema: schema, url: containerURL.appendingPathComponent("default.sqlite")) } else { config = ModelConfiguration(schema: schema) } self.container = try ModelContainer(for: schema, configurations: [config]) } Error in extension: fault: Attempt to add read-only file at path file:///private/var/mobile/Containers/Shared/AppGroup/51431199-5919-4AE6-940C-6FE3C53EEB46/default.sqlite read/write. Adding it read-only instead. This will be a hard error in the future; you must specify the NSReadOnlyPersistentStoreOption. error: (3) access permission denied error: Encountered exception error during prepareSQL for SQL string 'SELECT TBL_NAME FROM SQLITE_MASTER WHERE TBL_NAME = 'Z_METADATA'' : access permission denied with userInfo { NSFilePath = "/private/var/mobile/Containers/Shared/AppGroup/51431199-5919-4AE6-940C-6FE3C53EEB46/default.sqlite"; NSSQLiteErrorDomain = 3; } while checking table name from store: <NSSQLiteConnection: 0x154100300> error: Store failed to load. <NSPersistentStoreDescription: 0x15402d590> (type: SQLite, url: file:///private/var/mobile/Containers/Shared/AppGroup/51431199-5919-4AE6-940C-6FE3C53EEB46/default.sqlite) with error = Error Domain=NSCocoaErrorDomain Code=256 "The file “default.sqlite” couldn’t be opened." UserInfo={NSFilePath=/private/var/mobile/Containers/Shared/AppGroup/51431199-5919-4AE6-940C-6FE3C53EEB46/default.sqlite, NSSQLiteErrorDomain=3} with userInfo { NSFilePath = "/private/var/mobile/Containers/Shared/AppGroup/51431199-5919-4AE6-940C-6FE3C53EEB46/default.sqlite"; NSSQLiteErrorDomain = 3; } Any help appreciated 🙂

I am following Apple's instruction to sync SwiftData with CloudKit. While initiating the ModelContainer, right after removing the store from Core Data, the error occurs: FAULT: NSInternalInconsistencyException: This NSPersistentStoreCoordinator has no persistent stores (unknown). It cannot perform a save operation.; (user info absent) I've tried removing default.store and its related files/folders before creating the ModelContainer with FileManager but it does not resolve the issue. Isn't it supposed to create a new store when the ModelContainer is initialized? I don't understand why this error occurs. Error disappears when I comment out the #if DEBUG block. Code: import CoreData import SwiftData import SwiftUI struct InitView: View { @Binding var modelContainer: ModelContainer? @Binding var isReady: Bool @State private var loadingDots = "" @State private var timer: Timer? var body: some View { VStack(spacing: 16) { Text("Loading\(loadingDots)") .font(.title2) .foregroundColor(.gray) } .padding() .onAppear { startAnimation() registerTransformers() let config = ModelConfiguration() let newContainer: ModelContainer 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.my-container-identifier") desc.cloudKitContainerOptions = opts // Load the store synchronously so it completes before initializing the // CloudKit schema. desc.shouldAddStoreAsynchronously = false if let mom = NSManagedObjectModel.makeManagedObjectModel(for: [Page.self]) { let container = NSPersistentCloudKitContainer(name: "Pages", 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) } } // let fileManager = FileManager.default // let sqliteURL = config.url // let urls: [URL] = [ // sqliteURL, // sqliteURL.deletingLastPathComponent().appendingPathComponent("default.store-shm"), // sqliteURL.deletingLastPathComponent().appendingPathComponent("default.store-wal"), // sqliteURL.deletingLastPathComponent().appendingPathComponent(".default_SUPPORT"), // sqliteURL.deletingLastPathComponent().appendingPathComponent("default_ckAssets") // ] // for url in urls { // try? fileManager.removeItem(at: url) // } } #endif newContainer = try ModelContainer(for: Page.self, configurations: config) // ERROR!!! } catch { fatalError(error.localizedDescription) } modelContainer = newContainer isReady = true } .onDisappear { stopAnimation() } } private func startAnimation() { timer = Timer.scheduledTimer( withTimeInterval: 0.5, repeats: true ) { _ in updateLoadingDots() } } private func stopAnimation() { timer?.invalidate() timer = nil } private func updateLoadingDots() { if loadingDots.count > 2 { loadingDots = "" } else { loadingDots += "." } } } import CoreData import SwiftData import SwiftUI @main struct MyApp: App { @State private var modelContainer: ModelContainer? @State private var isReady: Bool = false var body: some Scene { WindowGroup { if isReady, let modelContainer = modelContainer { ContentView() .modelContainer(modelContainer) } else { InitView(modelContainer: $modelContainer, isReady: $isReady) } } } }

I'm running into a crash when trying to delete an item from a list that's loaded using SwiftData. The app works fine when selecting or displaying the data, but the moment I confirm a deletion, it crashes with this error: SwiftData/ModelSnapshot.swift:46: Fatal error: A ModelSnapshot must be initialized with a known-keys dictionary This happens right after I delete an item from the list using modelContext.delete(). I’ve double-checked that the item exists and is valid, and I'm not sure what I'm doing wrong. The data is loaded using @Query and everything seems normal until deletion. For further information, I have tried this on a new IOS project where I have one super Model class with a cascading relationship on a child class. When trying to delete the parent class while connected to one or more children, it still gives me the error. The same thing is happening with my original project. Class A has a relationship (cascading) with Class B. Attempting to delete Class A while there are relationships with Class B throws this error. If anyone has experienced this or knows what causes it, please let me know. I’m not even sure where to start debugging this one. Thanks in advance!

I am using SwiftData for my model. Until Xcode 15 beta 4 I did not have issues. Since beta 5 I am receiving the following red warning multiple times: 'NSKeyedUnarchiveFromData' should not be used to for un-archiving and will be removed in a future release This seems to be a CoreData warning. However, I am not using CoreData directly. I have no way to change the config of CoreData as used by SwiftData. My model just uses UUID, Int, String, Double, some of them as optionals or Arrays. I only use one attribute (.unique).

Hi all, I’m encountering a consistent issue with SwiftData on watchOS when using CloudKit sync. After enabling: let config = ModelConfiguration(schema: schema, cloudKitDatabase: .automatic) …the app terminates ~30–60 seconds into a WKExtendedRuntimeSession. This happens specifically when: Always-On Display is OFF The iPhone is disconnected or in Airplane Mode The app is running in a WKExtendedRuntimeSession (e.g., used for meditation tracking) The Xcode logs show a warning: Background Task ("CoreData: CloudKit Setup"), was created over 30 seconds ago. In applications running in the background, this creates a risk of termination. It appears CloudKit sync setup is being triggered automatically and flagged by the system as an unmanaged long-running task, leading to termination. Workaround: Switching to: let config = ModelConfiguration(schema: schema, cloudKitDatabase: .none) …prevents the issue entirely — no background task warning, no crash. Feedback ID submitted: FB17685611 Just wanted to check if others have seen this behavior or found alternative solutions. It seems like something Apple may need to address in SwiftData’s CloudKit handling on watchOS.

I'm seeing a lot of these in my logs: PersistentIdentifier PersistentIdentifier(id: SwiftData.PersistentIdentifier.ID(url: x-swiftdata://Course/BC9CF99A-DE6A-46F1-A18D-8034255A56D8), implementation: SwiftData.PersistentIdentifierImplementation) was remapped to a temporary identifier during save: PersistentIdentifier(id: SwiftData.PersistentIdentifier.ID(url: x-coredata:///Course/t58C849CD-D895-4773-BF53-3F63CF48935B210), implementation: SwiftData.PersistentIdentifierImplementation). This is a fatal logic error in DefaultStore ... though everything seems to work. Does anyone know what this means in this context? Anything I can do to not have this appear?