That's cool; amazing you indeed coded in MUMPS and not in ObjectScript ;-) Caché is (was) a great technology; ironically they tried to look like a relational database in the nineties, and then eventually came the NoSql boom. How did you get to MUMPS?
First job out of university and stuck around with it for the next dozen years, probably longer than sensible... in the context of maintaining a bag of software that got put together in the mid-80s, a substantial module of which continued to enjoy some moderate success to this day.
Also, the marketing term was post-relational if I recall correctly, the funny thing about that being that it was really pre-relational at first. Also, I forgot, it was IRIS this AOC stuff runs on - the $ZV actually needs that "R" in IRIS so it knows what label to jump to... and what file mode to use... it's wonderfully cursed ;P
That said, it doesn't hold a candle compared to this: https://stackoverflow.com/questions/4151554/need-mumps-sampl... which is just about the best obscured (or byte-saving rather) MUMPS snippet in existence.
One thing I miss about Caché/Ensemble/IRIS is the three different paradigms for manipulating the same bits of data - the whole object layer, SQL (with pre-compiled embedded SQL an option), and the raw global access.