Can i get/set the index generated by checking the 'indexed' checkbox? (core data)

I have 2 entities. entity A will hold many entity Bs and order will matter.

if i check the little box that says 'indexed' in xcode, how do i go about using that index, if i even can? ( i know that i CAN use it in some way: http://cocoawithlove.com/2008/03/testing-core-data-with-very-big.html but i am not so spiffy with Obj-c yet.)

I ha开发者_运维百科ve seen this Indexed Relationships in Core Data , but it seems broken and too much over my head to fix myself.

Index doesn't mean what you think it means. In this context, "indexed" means like the index of a book. It add a lookup table so the database can find individual records quickly. If you need to be able to sort the records into a specific order, use NSSortDescriptor with the NSFetchRequest. If the existing properties are not what you want to sort on, you'll need to add another property.