HI,
swiftdata is new to me and any help would be appreciated.
In my swiftui app I have a functionality that reinstates the database from an archive.
I first move the three database files (database.store datebase.store-wal and database.store-shm) to a new name (.tmp added for backup incase) and then copy the Archived three files to the same location.
the move creates the following errors:
" BUG IN CLIENT OF libsqlite3.dylib: database integrity compromised by API violation: vnode renamed while in use: /private/var/mobile/Containers/Data/Application/499A6802-02E5-4547-83C4-88389AEA50F5/Library/Application Support/database.store.tmp
invalidated open fd: 4 (0x20)"
I get the same message in console for all three files.
then I reinitialise the model container and get no errors as my code below
....
let schema = Schema([....my different models are here])
let config = ModelConfiguration("database", schema: schema)
do {
// Recreate the container with the same store URL
let container = try ModelContainer(for: schema, configurations: config)
print("ModelContainer reinitialized successfully!")
} catch {
print("Failed to reinitialize ModelContainer: (error)")
}
}
I get the success message but when I leave the view (backup-restore view) to the main view I get:
CoreData: error: (6922) I/O error for database at /var/mobile/Containers/Data/Application/499A6802-02E5-4547-83C4-88389AEA50F5/Library/Application Support/database.store. SQLite error code:6922, 'disk I/O error'
and
error: SQLCore dispatchRequest: exception handling request: <NSSQLFetchRequestContext: 0x302920460> , I/O error for database at /var/mobile/Containers/Data/Application/499A6802-02E5-4547-83C4-88389AEA50F5/Library/Application Support/database.store. SQLite error code:6922, 'disk I/O error' with userInfo of {
NSFilePath = "/var/mobile/Containers/Data/Application/499A6802-02E5-4547-83C4-88389AEA50F5/Library/Application Support/database.store";
NSSQLiteErrorDomain = 6922;
}
error: -executeRequest: encountered exception = I/O error for database at /var/mobile/Containers/Data/Application/499A6802-02E5-4547-83C4-88389AEA50F5/Library/Application Support/database.store. SQLite error code:6922, 'disk I/O error' with userInfo = {
NSFilePath = "/var/mobile/Containers/Data/Application/499A6802-02E5-4547-83C4-88389AEA50F5/Library/Application Support/database.store";
NSSQLiteErrorDomain = 6922;
}
CoreData: error: SQLCore dispatchRequest: exception handling request: <NSSQLFetchRequestContext: 0x302920460> , I/O error for database at /var/mobile/Containers/Data/Application/499A6802-02E5-4547-83C4-88389AEA50F5/Library/Application Support/database.store. SQLite error code:6922, 'disk I/O error' with userInfo of {
NSFilePath = "/var/mobile/Containers/Data/Application/499A6802-02E5-4547-83C4-88389AEA50F5/Library/Application Support/database.store";
NSSQLiteErrorDomain = 6922;
}
Can anyone let me know how I should go about this - reseting the database from old backup files by copying over them.
or if there is a way to stop the database and restart it with the new files in swiftdata
my app is an ios app for phone and ipad
iCloud & Data
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I've got an application built on top of SwiftData (+ CloudKit) which is published to App Store.
I've got a problem where on each app update, the data saved in the database is duplicated to the end user.
Obviously this isn't wanted behaviour, and I'm really looking forward to fixing it. However, given the restrictions of SwiftData, I haven't found a single fix for this.
The data duplication happens automatically on the first initial sync after the update. My guess is that it's because it doesn't detect the data already in the device, so it pulls all data from iCloud and appends it to the database where data in reality exists.
Problem Description:
When a device (Device 2) stays offline for an extended period after a record is deleted from another synced device (Device 1) via CloudKit, is it possible for Device 2 to miss the deletion notification when it reconnects, even when using CKSyncEngine?
This scenario raises questions about whether CKSyncEngine can reliably sync changes if CloudKit archives or purges metadata related to deletions during the offline period.
Steps to Reproduce:
At time t0:
· Device 1 and Device 2 sync successfully via CKSyncEngine (shared record RecordA).
Device 2 goes offline.
On Device 1:
· Delete RecordA; sync completes via CKSyncEngine.
Wait for a duration potentially exceeding CloudKit’s change retention window (if such a window exists).
Bring Device 2 back online.
Observe synchronization:
· Expected Behavior: CKSyncEngine removes RecordA from Device 2.
· Observed Behavior: RecordA remains on Device 2.
Key Questions:
Under these conditions, can Device 2 permanently miss the deletion event due to CloudKit’s internal metadata management?
Is there a documented retention policy for CloudKit’s change history, and how does CKSyncEngine handle scenarios where this history is truncated?
What is the recommended pattern to ensure no events are missed, regardless of offline duration?
Clarifications Needed:
· If CloudKit does discard deletion metadata after a period, is this considered a framework limitation, or should developers implement additional safeguards?
· Does CKSyncEngine log warnings or errors when it detects incomplete sync histories?
Environment:
· CKSyncEngine with SQLite
· CloudKit Private Database
· iOS/macOS latest versions
Thank you for clarifying how CKSyncEngine is designed to handle this edge case!
Hi,
I have developed a calendar app with swiftData. I have set it to sync iCloud. When testing it, it seems that everything is fine. But after it's released, today, I uninstalled it and reinstalled it again. And I found that iCloud hasn't sync with local swiftData for six days. I have lost six days agenda and relevant information. I have checked the document, and it's said that there is no method to force to sync with iCloud. How to solve the issue? I think that the users can't forgive that it hasn't synced for six days.
Best Wishes,
Topic:
App & System Services
SubTopic:
iCloud & Data
I am trying to port my application over to CloudKit. My app worked fine before, but then I made scheme of changes and am trying to deploy to a new container. For some reason, the database is not being created after I create the container through Xcode.
I think I have configured the app correctly and a container was created, but no records were deployed. My app current stores data locally on individual devices just fine but they don't sync with each other. That's why I would like to use CloudKit.
See screenshot from Xcode of where I have configured the container. I also have background notifications enabled. Also see screenshot from console where the container has been created, but no records have been.
Any suggestions would be greatly appreciated.
Thank you
I have a model with a FamilyActivitySelection, currently i'm using a codable struct to store it with UserDefaults, but would prefer strongly to transition to Swift Data
In my app, I've been using ModelActors in SwiftData, and using actors with a custom executor in Core Data to create concurrency safe services.
I have multiple actor services that relate to different data model components or features, each that have their own internally managed state (DocumentService, ImportService, etc).
The problem I've ran into, is that I need to be able to use multiple of these services within another service, and those services need to share the same context. Swift 6 doesn't allow passing contexts across actors.
The specific problem I have is that I need a master service that makes multiple unrelated changes without saving them to the main context until approved by the user.
I've tried to find a solution in SwiftData and Core Data, but both have the same problem which is contexts are not sendable. Read the comments in the code to see the issue:
/// This actor does multiple things without saving, until committed in SwiftData.
@ModelActor
actor DatabaseHelper {
func commitChange() throws {
try modelContext.save()
}
func makeChanges() async throws {
// Do unrelated expensive tasks on the child context...
// Next, use our item service
let service = ItemService(modelContainer: SwiftDataStack.shared.container)
let id = try await service.expensiveBackgroundTask(saveChanges: false)
// Now that we've used the service, we need to access something the service created.
// However, because the service created its own context and it was never saved, we can't access it.
let itemFromService = context.fetch(id) // fails
// We need to be able to access changes made from the service within this service,
/// so instead I tried to create the service by passing the current service context, however that results in:
// ERROR: Sending 'self.modelContext' risks causing data races
let serviceFromContext = ItemService(context: modelContext)
// Swift Data doesn't let you create child contexts, so the same context must be used in order to change data without saving.
}
}
@ModelActor
actor ItemService {
init(context: ModelContext) {
modelContainer = SwiftDataStack.shared.container
modelExecutor = DefaultSerialModelExecutor(modelContext: context)
}
func expensiveBackgroundTask(saveChanges: Bool = true) async throws -> PersistentIdentifier? {
// Do something expensive...
return nil
}
}
Core Data has the same problem:
/// This actor does multiple things without saving, until committed in Core Data.
actor CoreDataHelper {
let parentContext: NSManagedObjectContext
let context: NSManagedObjectContext
/// In Core Data, I can create a child context from a background context.
/// This lets you modify the context and save it without updating the main context.
init(progress: Progress = Progress()) {
parentContext = CoreDataStack.shared.newBackgroundContext()
let childContext = NSManagedObjectContext(concurrencyType: .privateQueueConcurrencyType)
childContext.parent = parentContext
self.context = childContext
}
/// To commit changes, save the parent context pushing them to the main context.
func commitChange() async throws {
// ERROR: Sending 'self.parentContext' risks causing data races
try await parentContext.perform {
try self.parentContext.save()
}
}
func makeChanges() async throws {
// Do unrelated expensive tasks on the child context...
// As with the Swift Data example, I am unable to create a service that uses the current actors context from here.
// ERROR: Sending 'self.context' risks causing data races
let service = ItemService(context: self.context)
}
}
Am I going about this wrong, or is there a solution to fix these errors?
Some services are very large and have their own internal state. So it would be very difficult to merge all of them into a single service. I also am using Core Data, and SwiftData extensively so I need a solution for both.
I seem to have trapped myself into a corner trying to make everything concurrency save, so any help would be 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 just released an App update the didn't touch ANYTHING to do with Core Data (nothing changed in our Coredata code for at least 8 months). The update uses SDK for iOS 18 and Xcode 16.2 and the app now requires iOS 18 and was a minor bug patch and UI improvements for recent iOS changes.
Since the update we are getting a steady trickle of users on iOS 18, some who allow the App to store data in iCloud (Cloudkit) and others who do not, all reporting that after the update to our recent release ALL their data is gone?!
I had not seen this on ANY device until today when I asked a friend who uses the App if they had the issue and it turned out they did, so I hooked their device up to Xcode and ALL the data in the CoreData database was gone?! They are NOT using iCloud. There were no errors or exceptions on Xcode console but a below code returned NO records at all?!
Chart is custom entity and is defined as:
@interface Chart : NSManagedObject {}
let moc = pc.viewContext
let chartsFetch = NSFetchRequest<NSFetchRequestResult>(entityName:"Charts") // Fetch all Charts
do {
let fetchedCharts = try moc.fetch(chartsFetch) as! [Chart]
for chart in fetchedCharts {
....
}
}
A break point inside the do on fetchedCharts show there are NO objects returned.
This is a serious issue and seems like an iOS 18 thing. I saw some people talking in here about NSFetchRequest issues with iOS 18. I need some guidance here from someone Apple engineer here who knows what the status of these NSFetchrequest bugs are and what possible workarounds are. Becasue this problem will grow for me as more users update to iOS 18.
Hello,
My app has had CloudKit enabled for a while, but it's not working. I get the error "Invalid bundle ID for container".
Configure CloudKit in your project from TN3164 suggests changing to a new container. I tried changing to a new container, but this leads to data loss.
The article recommends:
"If your CloudKit container is already used in the production environment and switching to a new container leads to data loss, consider filing a feedback report with the following information to request manually associating your CloudKit container with your app ID."
Where can I request this manual association? Is there anything else I can do?
Thank you for your time and assistance. I’d appreciate a prompt resolution, as this issue is blocking our update. Looking forward to guidance.
I have a very simple CoreData model that has 1 entity and 2 attributes.
This code works fine:
.onChange(of: searchText) { _, text in
evnts.nsPredicate = text.isEmpty ? nil :NSPredicate(format: "eventName CONTAINS %@ " , text )
but I'd like to also search with the same text string for my second attribute (which is a Date). I believe an OR is appropriate for two conditions (find either one). See attempted code below:
evnts.nsPredicate = text.isEmpty ? nil : NSPredicate(format: "(eventName CONTAINS %@) OR (dueDate CONTAINS %i) " , text )
This crashes immediately %@ does the same. Is there a way to accomplish this?
How is SwiftUI not an option below?
Hi,
I have designed an app which needs to reschedule notifications according to the user's calendar at midnight. The function has been implemented successfully via backgroundtask. But since the app has enabled iCloud sync, some users will edit their calendar on their iPad and expect that the notifications will be sent promptly to them on iPhone without launching the app on their iPhone. But the problem is that if they haven't launched the app on their iPhone, iCloud sync won't happen. The notifications on their iPhone haven't been updated and will be sent wrongly. How can I design some codes to let iCloud sync across the devices without launching the app at midnight and then reschedule notifications?
Hi,
Before the iOS 17.2 update the saving behavior of SwiftData was very straightforward, by default it saves to persistence storage and can be configured to save in memory only. Now it saves to memory by default and to make it save to persistence storage we need to use modelContext.Save(). But if we don't quit the App the changes will be saved after a while to persistence storage even without running modelContext.Save() ! How confusing can that be for both developer and the user ! Am I missing something here ?
--
Kind Regards
I have an app which uses ubiquitous containers and files in them to share data between devices. It's a bit unusual in that it indexes files in directories the user grants access to, which may or may not exist on a second device - those files are identified by SHA-1 hash. So a second device scanning before iCloud data has fully sync'd can create duplicate references which lead to an unpleasant user experience.
To solve this, I store a small binary index in the root of the ubiquitous file container of the shared data, containing all of the known hashes, and as the user proceeds through the onboarding process, a background thread is attempting to "prime" the ubiquitous container by calling FileManager.default.startDownloadingUbiquitousItemAt() for each expected folder and file in a sane order.
This likely creates a situation not anticipated by the iOS/iCloud integration's design, as it means my app has a sort of precognition of files it should not yet know about.
In the common case, it works, but there is a corner case where iCloud sync has just begun, and very, very little metadata is available (the common case, however, in an emulator), in which two issues come up:
I/O may hang indefinitely, trying to read a file as it is arriving. This one I can work around by running the I/O in a thread created with the POSIX pthread_create and using pthread_cancel to kill it after a timeout.
Attempts to call FileManager.default.startDownloadingUbiquitousItemAt() fails with an error Error Domain=NSCocoaErrorDomain Code=257 "The file couldn’t be opened because you don’t have permission to view it.". The permissions aspect of it is nonsense, but I can believe there's no applicable "sort of exists, sort of doesn't" error code to use and someone punted. The problem is that this same error will be thrown on any attempt to access that file for the life of the application - a restart is required to make it usable.
Clearly, the error or the hallucinated permission failure is cached somewhere in the bowels of iOS's FileManager. I was hoping startAccessingSecurityScopedResource() would allow me to bypass such a cache, as it does with URL.resourceValues() returning stale file sizes and last modified times. But it does not.
Is there some way to clear this state without popping up a UI with an Exit button (not exactly the desired iOS user experience)?
Topic:
App & System Services
SubTopic:
iCloud & Data
Tags:
Foundation
Files and Storage
iOS
iCloud Drive
anyone getting the following error with CloudKit+CoreData on iOS16 RC?
delete/resintall app, delete user CloudKit data and reset of environment don't fix.
[error] error: CoreData+CloudKit: -[NSCloudKitMirroringDelegate _requestAbortedNotInitialized:](2044): <NSCloudKitMirroringDelegate: 0x2816f89a0> - Never successfully initialized and cannot execute request '<NSCloudKitMirroringImportRequest: 0x283abfa00> 41E6B8D6-08C7-4C73-A718-71291DFA67E4' due to error: Error Domain=NSCocoaErrorDomain Code=4864 "*** -[NSKeyedUnarchiver _initForReadingFromData:error:throwLegacyExceptions:]: incomprehensible archive (0x53, 0x6f, 0x6d, 0x65, 0x20, 0x65, 0x78, 0x61)" UserInfo={NSDebugDescription=*** -[NSKeyedUnarchiver _initForReadingFromData:error:throwLegacyExceptions:]: incomprehensible archive (0x53, 0x6f, 0x6d, 0x65, 0x20, 0x65, 0x78, 0x61)}
Some users of my app are reporting total loss of data while using the app.
This is happening specifically when they enable iCloud sync.
I am doing following
private func setupContainer(enableICloud: Bool) {
container = NSPersistentCloudKitContainer(name: "")
container.viewContext.automaticallyMergesChangesFromParent = true
container.viewContext.mergePolicy = NSMergeByPropertyObjectTrumpMergePolicy
guard let description: NSPersistentStoreDescription = container.persistentStoreDescriptions.first else {
fatalError()
}
description.setOption(true as NSNumber, forKey: NSPersistentHistoryTrackingKey)
description.setOption(true as NSNumber, forKey: NSPersistentStoreRemoteChangeNotificationPostOptionKey)
if enableICloud == false {
description.cloudKitContainerOptions = nil
}
container.loadPersistentStores { description, error in
if let error {
// Handle error
}
}
}
When user clicks on Toggle to enable/disable iCloud sync I just set the description.cloudKitContainerOptions to nil and then user is asked to restart the app.
Apart from that I periodically run the clear history
func deleteTransactionHistory() {
let sevenDaysAgo = Calendar.current.date(byAdding: .day, value: -7, to: Date())!
let purgeHistoryRequest = NSPersistentHistoryChangeRequest.deleteHistory(before: sevenDaysAgo)
let backgroundContext = container.newBackgroundContext()
backgroundContext.performAndWait {
try! backgroundContext.execute(purgeHistoryRequest)
}
}
I am having problems when I first loads the app. The time it takes for the Items to be sync from my CloudKit to my local CoreData is too long.
Code
I have the model below defined by my CoreData.
public extension Item {
@nonobjc class func fetchRequest() -> NSFetchRequest<Item> {
NSFetchRequest<Item>(entityName: "Item")
}
@NSManaged var createdAt: Date?
@NSManaged var id: UUID?
@NSManaged var image: Data?
@NSManaged var usdz: Data?
@NSManaged var characteristics: NSSet?
@NSManaged var parent: SomeParent?
}
image and usdz columns are both marked as BinaryData and Attribute Allows External Storage is also selected.
I made a Few tests loading the data when the app is downloaded for the first time. I am loading on my view using the below code:
@FetchRequest(
sortDescriptors: [NSSortDescriptor(keyPath: \Item.createdAt, ascending: true)]
)
private var items: FetchedResults<Item>
var body: some View {
VStack {
ScrollView(.vertical, showsIndicators: false) {
LazyVGrid(columns: columns, spacing: 40) {
ForEach(items, id: \.self) { item in
Text(item.id)
}
}
}
}
}
Test 1 - Just loads everything
When I have on my cloudKit images and usdz a total of 100mb data, it takes around 140 seconds to show some data on my view (Not all items were sync, that takes much longer time)
Test 2 - Trying getting only 10 items at the time ()
This takes the same amount of times the long one . I have added the following in my class, and removed the @FetchRequest:
@State private var items: [Item] = [] // CK
@State private var isLoading = false
@MainActor
func loadMoreData() {
guard !isLoading else { return }
isLoading = true
let fetchRequest = NSFetchRequest<Item>(entityName: "Item")
fetchRequest.predicate = NSPredicate(format: "title != nil AND title != ''")
fetchRequest.fetchLimit = 10
fetchRequest.fetchOffset = items.count
fetchRequest.predicate = getPredicate()
fetchRequest.sortDescriptors = [NSSortDescriptor(keyPath: \Item.createdAt, ascending: true)]
do {
let newItems = try viewContext.fetch(fetchRequest)
DispatchQueue.main.async {
items.append(contentsOf: newItems)
isLoading = false
}
} catch {}
}
Test 2 - Remove all images and usdz from CloudKit set all as Null
Setting all items BinaryData to null, it takes around 8 seconds to Show the list.
So as we can see here, all the solutions that I found are bad. I just wanna go to my CloudKit and fetch the data with my CoreData. And if possible to NOT fetch all the data because that would be not possible (imagine the future with 10 or 20GB or data) What is the solution for this loading problem? What do I need to do/fix in order to load lets say 10 items first, then later on the other items and let the user have a seamlessly experience?
Questions
What are the solutions I have when the user first loads the app?
How to force CoreData to query directly cloudKit?
Does CoreData + CloudKit + NSPersistentCloudKitContainer will download the whole CloudKit database in my local, is that good????
Storing images as BinaryData with Allow external Storage does not seems to be working well, because it is downloading the image even without the need for the image right now, how should I store the Binary data or Images in this case?
I have a SwiftData application that is using CloudKit. If user is on new device. How can I check and fetch data, instead of just waiting for it happen on its own randomly?
For example, I have onboarding which I do not want user to go through again if they already have an active installation.
Seems like SwiftData is severely limited in pretty much every way, specially any useful CloudKit debugging or control functionality.
I implemented the cloudkit function, where users can connect with each other. The problem is, that if User A is doing a friend request and User B is accepting the request. The friend entry is correct visible for User B but not for User A. I can see in cloud kit that after the accepted request, the friend connection is set up correctly, also with the correct userID, but it not showing up for User A (the one that send the request)
Topic:
App & System Services
SubTopic:
iCloud & Data
Tags:
CloudKit
CloudKit Dashboard
CloudKit Console
if it set com.apple.CoreData.ConcurrencyDebug 1 as launch arg the app always crashes and i cant proceed into the app. is there a way to only raise a warning for these issues so that i can go into the app and check every place in one session for coredata errors?