A Massive Speed Difference in iPhone Core Data

Samuel Goodwin:

It was brought to my attention last night by my good friend, Collin Donnell, that using a fetch request to grab objects based on their objectID’s was much slower than simply using a for loop and the NSManagedObjectContext method -existingObjectWithID:error: to grab each object one by one. My initial response was supreme disbelief. How could this be true? I needed a break today from my pile of work to do, so I thought I would investigate and see what’s up.