I must execute some type of subquery with my fetchedresultscontroller. I have got some products that have a flag like "seen" or "not seen". Can you really switch between these products... I could perform a complete refetch but this takes a while. It is possible to better method for carrying this out?

Thank you!

One option is to possess two versions of the NSFetchedResultsController, one for seen and something because of not seen. The secret would be to make certain they will use different cache files. This can permit the switching to become nearly immediate when the initial population from the cache is done.

You may also arrange it to ensure that only one of these simple is within memory at any given time to help keep the overhead low. The secret would be to make certain the cache names and fetch demands are consistent to ensure that you don't trigger a cache totally reset.