Up to now, there were two space index types: 'BASIC' for equality (==) and 'EXTENDED' for equality and order (<, >).
The 'EXTENDED' index type maintains two data structures to support both query types, which requires extra memory footprint.
We're now introducing 3 new space index types:
EQUAL - for matching equality (==), same as BASIC (which is now deprecated)
ORDERED - for matching ordered (<, >). Also speeds up equality but not as fast.
EQUAL_AND_ORDERED - for matching both equality and order, same as EXTENDED (which is now deprecated)