Why is Core Data shm file not removed in journal_mode DELETE?

Question

I'm using the following code to to consolidate my Core Data sqlite store files, which current consists of the database itself, a -wal and a -shm file. I am doing this so I can manipulate it as a single file using NSFileManager.

NSPersistentStoreCoordinator *tmpPSC = [[NSPersistentStoreCoordinator alloc] 
      initWithManagedObjectModel...];

NSDictionary *options = @{NSSQLitePragmasOption: 
                        @{@"journal_mode": @"DELETE"}};

NSPersistentStore *persistentStore = [tmpPSC 
   addPersistentStoreWithType:NSSQLiteStoreType configuration:nil 
   URL:storeURL options:options error:NULL];

if (persistentStore) {
   [tmpPSC removePersistentStore:persistentStore error:NULL];
   tmpPSC = nil;
}

However, after the above code execute, I am seeing the -wal file disappear, but the -shm file is still there.

Any idea why this is so?

score 0 · Answer 1 · edited May 23 '17 at 10:10

0

Never mind, found my answer here:

How to save the content of a MOC to a file, with no -wal and no -shm?

shm file can safely be deleted, which is what I did.

edited May 23 '17 at 10:10

Community

1
1

answered Mar 25 '15 at 10:24

Eric

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and at what moment do you delete it? – vomi Apr 17 '20 at 18:42

Why is Core Data shm file not removed in journal_mode DELETE?

1 Answers1