My entity has a startDate (NSTime) attribute where I use the date and time in my detail display of the entity.
And in my list, I need to group my entities by day (YYMMDD) based on the start date; and I want to ensure that it can adapt to the region where the user is currently (e.g. if user travels or migrate, the YYMMDD should be adapted based on the current region). Does Core Data SectionedFetchRequest supports strftime() functions from SQLite (https://sqlite.org/lang_datefunc.html) or what is an effective alternative sectioned fetch in my case?
iCloud & Data
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I am developing an app that uses CloudKit sharing. I recently upgraded my iPad to use 23A5336a. After that upgrade, I can no longer accept a share that is sent to me.
I have rebooted the iPad and logged out of the iCloud account and logged back in. Every time I get a share link and tap it, it says:
" The owner stopped sharing or your account (xxx) doesn't have permission to open it"
This same code, running on the iOS26 device can share with device running iOS18.
Is this a known defect? Anything I can do to help resolve this issue?
I'm setting up App Entities for my SwiftData models and I'm not sure about the best way to reference SwiftData model properties in the AppEntity.
I have a SwiftData model with many properties:
@Model
final class Contact {
@Attribute(.unique) var id: UUID = UUID()
var name: String
var phoneNumber: String
var email: String
var website: URL?
var birthday: Date?
var notes: String
// ... many more properties
}
I want to expose these properties on my AppEntity so they're available for system features, such as giving Apple Intelligence more context about on-screen content.
struct ContactEntity: AppEntity {
var id: UUID
@Property(title: "Name")
var name: String
@Property(title: "Phone")
var phoneNumber: String
@Property(title: "Email")
var email: String
// ... all the other properties
}
I couldn't find guidance in the documentation for this specific situation. I've considered two approaches:
Add @Property variables to the AppEntity for each SwiftData model property and copy all values from the SwiftData model to the AppEntity in the AppEntity initializer — but I recall this being discouraged in previous WWDC sessions since it duplicates data and can become stale
Use @ComputedProperty to fetch the model and access the single properties — this seems like an alternative, but fetching the entire model just to access individual properties doesn't feel right
What is the recommended approach when SwiftData is the data source?
Thank you!
i want to save data like images, text,amd mapviews with swiftui. It is only saved but if you delete the app of buy a new iPhone everything is deleted, how can I make if that the information saved on my app is saved even after I update the app, delete the app, or put the app in another iPhone with SwiftUI? i have watched youtube videos and im still confused,please help.
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?
I'm trying to set up an application using SwiftData to have a number of models backed by a local datastore that's not synced to CloudKit, and another set of models that is. I was able to achieve this previously with Core Data using multiple NSPersistentStoreDescription instances.
The set up code looks something like:
do {
let fullSchema = Schema([
UnsyncedModel.self,
SyncedModel.self,
])
let localSchema = Schema([UnsyncedModel.self])
let localConfig = ModelConfiguration(schema: localSchema, cloudKitDatabase: .none)
let remoteSchema = Schema([SyncedModel.self])
let remoteConfig = ModelConfiguration(schema: remoteSchema, cloudKitDatabase: .automatic)
container = try ModelContainer(for: fullSchema, configurations: localConfig, remoteConfig)
} catch {
fatalError("Failed to configure SwiftData container.")
}
However, it doesn't seem to work as expected. If I remove the synced/remote schema and configuration then everything works fine, but the moment I add in the remote schema and configuration I get various different application crashes. Some examples below:
A Core Data error occurred." UserInfo={Reason=Entity named:... not found for relationship named:...,
Fatal error: Failed to identify a store that can hold instances of SwiftData._KKMDBackingData<...>
Has anyone ever been able to get a similar setup to work using SwiftData?
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
I'm using SwiftData with CloudKit private database. I was able to identify the error on my device by debugging in Xcode with com.apple.CoreData.SQLDebug flag. However, in Production, I couldn't find a way to get the cause of errors.
I tried inspecting the error coming from eventChangedNotification. The NSPersistentCloudKitContainer.Event error does not contain any underlying error (neither CKError.userInfo nor in NSError.underlyingError). It only reports a partial failure with CKErrorDomain code 2.
If a user encounter an error, there seems to be no way to retrieve the error details.
Is there any way to access the error details or logs in Production?
Running Tahoe 26.1 in a virtual machine, I can't sign into my Apple account. There is an error message saying "Could not communicate with the server." Internet access otherwise seems to be working in the VM. I tried both UTM and VirtualBuddy. Is this supposed to work?
Does the CloudKit participant limit of 100 include the owner?
As of 2025-05-03, when a macOS user enables iCloud Drive synchronization for Desktop & Documents in US region, does iCloud filter xattrs upon upload or later when downloading back to another macOS host? Or is it the case that iCloud has no filtering of third-party xattrs? Where can I find the technical document outlining exactly what iCloud does with xattrs set on macOS host files and folders synchronized with iCloud Drive?
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
Topic:
App & System Services
SubTopic:
iCloud & Data
Tags:
Files and Storage
On demand resources
Core Data
Background Assets
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)
}
}
Here’s the situation:
• You’re downloading a huge list of data from iCloud.
• You’re saving it one by one (sequentially) into SwiftData.
• You don’t want the SwiftUI view to refresh until all the data is imported.
• After all the import is finished, SwiftUI should show the new data.
The Problem
If you insert into the same ModelContext that SwiftUI’s @Environment(.modelContext) is watching, each insert may cause SwiftUI to start reloading immediately.
That will make the UI feel slow, and glitchy, because SwiftUI will keep trying to re-render while you’re still importing.
How to achieve this in Swift Data ?
I have one target building and filling the SwiftData store and then copying the same store file to another target of the app to use the contents.
That worked fine from iOS 17 to iOS 26.0.1
Under iOS 26.1 I am getting following error:
CoreData: error:
This store file was previously used on a build with Persistence-1522 but is now running on a build with Persistence-1518.
file:///Users/xxx/Library/Developer/CoreSimulator/Devices/0FE92EA2-57FA-4A5E-ABD0-DAB4DABC3E02/data/Containers/Data/Application/B44D3256-9B09-4A60-94E2-C5F11A6519E7/Documents/default.store
What does it mean and how to get back to working app under iOS 26.1?
Updated the phone to iOS 26.1 and now the app is not working anymore, even previously approved version published on App Store which works perfectly on iOS 26.0.1, and iOS 18+.
I deleted the app from the phone and installed fresh from App Store, still the same.
Logic is that on start app copies previously prepared SwiftData store file (using the same models) from app bundle to Documents directory and uses it.
Currently app just hungs with loader spinner spinning as it can t connect to the store.
Getting this error in console when running from Xcode on real device with iOS 26.1 installed:
CoreData: error:
CoreData: error: Store failed to load. <NSPersistentStoreDescription: 0x10c599e90> (type: SQLite, url: file:///var/mobile/Containers/Data/Application/DA32188D-8887-48F7-B828-1F676C8FBEF8/Documents/default.store)
with error = Error Domain=NSCocoaErrorDomain Code=134140
"Persistent store migration failed, missing mapping model."
UserInfo={sourceModel=(<NSManagedObjectModel: 0x10c503ac0>) isEditable 0,
entities { /// there goes some long models description
addPersistentStoreWithType:configuration:URL:options:error: returned error NSCocoaErrorDomain (134140)
Any help or workaround will be greatly appreciated.
Hi,
I am implementing a premium feature in my app where CloudKit syncing is available only for "Pro" users.
The Workflow:
Free Users: I initialize the ModelContainer with cloudKitDatabase: .none so their data stays local.
Pro Upgrade: When a user purchases a subscription, I restart the container with cloudKitDatabase: .automatic to enable syncing.
The Problem:
If a user starts as "Free" (creates local data) and later upgrades to "Pro", the app crashes immediately upon launch with the following error:
Fatal error: Failed to create ModelContainer: SwiftDataError(_error: SwiftData.SwiftDataError._Error.loadIssueModelContainer, _explanation: nil)
It seems that SwiftData fails to load the existing data once the configuration changes to expect a CloudKit-backed store.
My Question:
Is there a supported way to "toggle" CloudKit on for an existing local dataset without causing this crash? I want the user's existing local data to start syncing once they pay, but currently, it just crashes.
My code:
import Foundation
import SwiftData
public enum DataModelEnum: String {
case task, calendar
public static let container: ModelContainer = {
let isSyncEnabled = UserDefaults.isProUser
let config = ModelConfiguration(
groupContainer: .identifier("group.com.yourcompany.myApp"),
cloudKitDatabase: isSyncEnabled ? .automatic : .none
)
do {
return try ModelContainer(for: TaskModel.self, CalendarModel.self, configurations: config)
} catch {
fatalError("Failed to create ModelContainer: \(error)")
}
}()
}
Topic:
App & System Services
SubTopic:
iCloud & Data
Tags:
CloudKit
Cloud and Local Storage
SwiftData
I am using cloudkit to save users high scores in a public database. The preference over using Game Center is because of simplicity and works really well for what I want to achieve. I simply want to let users know their global position. Because of data privacy laws the app asks the user for their permission to submit their score each time they get a new high score.
However, I have noticed that CKRecords under 'created' and 'modified' in addition to UTC time and date also contain creatorUserRecordID. Could this be a privacy issue? Can you extract any personal information from this? Can this be used to track back to the user? Is it linked to CKUserIdentity which I understand does contain personal information, although as I understand you need users consent to get this information. Under creatorUserRecordID it says... "Every user of the app has a unique user record that is empty by default. Apps can add data to the user record on behalf of the user, but don’t store sensitive data in it"
Currently I simply ask the user if they are happy to submit their score. But do I need to point out that it also stores a creatorUserRecordID? Obviously I don't want to do this if it is not needed as the user will 1) Probably not understand what a creatorUserRecordID is and 2) It makes the question complicated and will likely make most people refuse to submit their score.
If it is a privacy issue, is there anyway to stop a CKRecord creating this ID and simply save a score? All I need is a list of scores so the app can determine their current position.
If creatorUserRecordID does not contain any personal details and cannot be tracked back to the user please let me know, so I can be reassured that my current set up is fine and I am not causing any privacy issues!
This post did seem to indicate you may possibly be able to fetch personal details??
https://stackoverflow.com/questions/55782166/how-do-i-fetch-any-info-about-user-that-modified-ckrecord
Users have been reporting that the TestFlight version of my app (compiled with Xcode 26 Beta 6 17A5305f) is sometimes crashing on startup. Upon investigating their ips files, it looks like Core Data is locking up internally during its initialization, resulting in iOS killing my app. I have not recently changed my Core Data initialization logic, and it's unclear how I should proceed.
Is this a known issue? Any recommended workaround? I have attached the crash stack below.
Thanks!
crash_log.txt
While experimenting with CloudKit dashboard, I accidentally turned off a iCloud container.
Now in the Certificates, Identifiers & Profiles section of developer portal, this iCloud container identifier is listed under "hidden" not "active"
I can edit its name but there is not way to unhide or active it again.
What am I missing?
Topic:
App & System Services
SubTopic:
iCloud & Data