Tom Harrington notes that several developers (including James Dempsey and Rich Siegel) have encountered a bug with Core Data’s -[NSPersistentStoreCoordinator migratePersistentStore:toURL:options:withType:error:] method. This is supposed to copy the data store from one location to another, e.g. for making a backup. The frameworks may also call the method on your behalf, e.g. if the user does … Continue reading Core Data Relationships Data Loss Bug