在CoreData中执行批量INSERT / UPDATE / DELETE的有效方法。

I've got a JSON object containing 200,000 items. I need to iterate through these objects, and determine if they exist or not and perform the relevant action (insert / update / delete). The shell for this is shown below. Granted, it's not actually saving anything yet. It was more to see how long this way would take. This action takes about 8 minutes to process on an iPhone 4, which seems insane, considering there isn't even any changes occurring yet. I've got a JSON object containing 200,000 items