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I am new to sqlite. I successfully implemented CRUD methods to CloudKit in my app. I am not using Core Data. I read in the Apple developer documentation on Remote Records that:

CloudKit stores your records in iCloud and uses subscriptions to notify your app in real time about record changes. You then use change tokens to handle these changes efficiently. Additionally, you can improve your app’s performance and support offline use by storing records in a local cache.

I am interested in this local cache. After some digging around, it looks like this cache is automatically created and stored in the container referenced in AppDelegate.swift. I put a breakpoint in my code, and in the Debug Console, I typed: po (UIApplication.shared.delegate as! AppDelegate).persistentContainer to discover where the .sqlite file is located. It shows:

<NSPersistentCloudKitContainer: 0x600002934c40> CoreData: debug: CoreData+CloudKit: -NSCloudKitMirroringDelegate observeChangesForStore:inPersistentStoreCoordinator:: <NSCloudKitMirroringDelegate: 0x6000007e9d40>: Observing store: <NSSQLCore: 0x7f8276e1cc70> (URL: file:///Users/xxxxxxxx/Library/Developer/CoreSimulator/Devices/30CE52B9-E246-4B40-82F4-13DBE48EB7D6/data/Containers/Data/Application/5E26076E-12F0-4E86-9B1D-BED642C01BB6/Library/Application%20Support/MyAppName.sqlite)

In a Terminal window, I typed:

open file:///Users/xxxxxxxx/Library/Developer/CoreSimulator/Devices/30CE52B9-E246-4B40-82F4-13DBE48EB7D6/data/Containers/Data/Application/5E26076E-12F0-4E86-9B1D-BED642C01BB6/Library/Application%20Support/MyAppName.sqlite

It opened the .sqlite file in Liya. I see a bunch of tables like these:

Tables shown in Liya.

I inspected each table in the list. None of the table names match the name of the Record Type and none of the field names match the names of the Record Fields that I see in the CloudKit Dashboard. So, is this .sqlite file really the cache that CloudKit created locally to "mirror" the database in iCloud? If so, how do I make use of this local cache when I can't even recognize the table name or field names used in my app?

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The database you are viewing is, in fact, Core Data. When you use NSPersistentCloudKitContainer with CloudKit, your app will use Core Data as the local cache.

The SQLite database that Core Data uses is not meant to be manipulated directly since the Core Data framework manages how and when data is transacted with SQLite. You should only interface with the Core Data framework in your app and not worry about what is happening under the hood in SQLite.

If you want raw access to SQLite and full control over how your data is named and structured, then you will need to do things manually. You will need to setup and manage your own SQLite transactions and then manually manage how you sync with CloudKit.

Here are a couple good options for SQLite frameworks:

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I see that I did add import CoreData to AppDelegate.swift even though I didn't actually do anything with Core Data. All I am sure of is that CloudKit is working fine confirmed by what I see on the CK Dashboard. So you're saying that the presence of the .sqlite file means that Core Data does in fact "mirror" what I have in CloudKit without my having to do anything? There is a MyAppName.xcdatamodeld file in my project but it is empty. Do I need to populate it to match my CloudKit private database schema before I can access it in my app?
My experience with NSPersistentCloudKitContainer per se is somewhat limited, but I think you want to define your record types using the Core Data model definitions in your . xcdatamodeld file, and not change them in the CloudKit Dashboard.

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