Updating live app in store to use Core Data that currently does not use Core Data

I currently have an app in the store which is SQLite-backed and does not use Core Data. In the past when I have wanted to release an update that had SQLite changes, the update would include some code that would detect the version of the app, and programmatically update the tables if necessary. Now I am working on an update that uses Core Data. I don't care about any of the old data that is currently live, and I know how I can delete all the old SQLite tables programmatically. Are all the Core Data model files included in the update binary, or do I have to programmatically generate some or 开发者_开发知识库all of the Core Data model? Will the .xcdatamodeld be included with the binary? Any other pitfalls I should be wary of?

Thanks for your help

With core data it can be quite tricky when updating to a new version. I have experienced many times that even the slightest changes in the core data model cause weird app behaviour (understandable to some extend). The easiest way to avoid any unwanted sideeffects is to just change the name. Here the code

- (NSPersistentStoreCoordinator *) persistentStoreCoordinator {
//  D_IN;   
if (persistentStoreCoordinator != nil) {
    return persistentStoreCoordinator;
}
persistentStoreCoordinator = [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel: [self managedObjectModel]];

// Allow inferred migration from the original version of the application.
NSDictionary *options = [NSDictionary dictionaryWithObjectsAndKeys:
                         [NSNumber numberWithBool:YES], NSMigratePersistentStoresAutomaticallyOption,
                         [NSNumber numberWithBool:YES], NSInferMappingModelAutomaticallyOption, nil];

NSURL *storeUrl = [NSURL fileURLWithPath: [[self applicationDocumentsDirectory] stringByAppendingPathComponent: @"myData073.sqlite"]];

NSError *error = nil;

if (![persistentStoreCoordinator addPersistentStoreWithType:NSSQLiteStoreType configuration:nil URL:storeUrl 
                                                    options:options error:&error]){
    NSLog(@"Unresolved error %@, %@", error, [error userInfo]);


}
//  D_OUT;

return persistentStoreCoordinator;

}

So all you really have to do is to change the name myData073.sqlite to for example myData074.sqlite

The data model description file is not really part of the binary, but the model behind it with all the classes and access methods surely is. You do not need to worry about that. ps even during development I change the name frequently, otherwise one might waste lots of time looking for coding errors that are not really there...

An App Store update replaces the entire app bundle, so everything in your app bundle, including any Core Data model, will be included. You can test this by installing an Ad Hoc or developer build over an App Store build on your own device (without deleting first). In the compiled App, the model files are compiled or processed, and have different extensions (.momd, .mom). So you'll see those instead of .xcdatamodeld or .xcdatamodel.

Other pitfalls: Now, the Core Data data file is not part of your bundle. If you want the updated app to start with an empty database, you don't have to do anything special. But if you want to install/update with a prepopulated database, you have to figure out a way to get that database into a read-write location on the device. Basically, you generate a Core Data file, included it in the app bundle as part of your Xcode project, then at first launch, programmatically copy it somewhere in your Documents or Library folders (using the correct Cocoa API for finding these).

Pitfall #2: modifying an empty core data file with SQLLite on the Mac is suggested on some web sites, but specifically dis-recommended by Apple. Instead, you might write an iOS app that puts data into core data and run it in the simulator. How do I initialize a store with default data?

As user387184 indicated, your next update that changes the model on an existing Core Data database can get tricky. Try to get the model as right as you can the first time.