Talking to Algebraix reminded me that David Childs is still alive and kicking. I only ever encountered Childs once, in the early/mid-1980s, when he was pushing his company Set Theoretic Information Systems. The main customer example for STIS was General Motors, for which he had achieved a remarkable amount of database compression. It was something like 4-5X, if I recall correctly, but for 1983 or whatever that was pretty darned good. The idea was to replace data by partitioning according to shared values. E.g., you didn’t store whether cars were red, blue, or green; instead, you stored records about all the red cars in one place, the blue cars in another, and so on. There was also some set-theoretic mumbo-jumbo, but I never figured out what it had to do with implementing anything.
Comshare — a BI vendor before anybody called it BI — did actually build a DBMS based on Childs’ ideas, as Ron Jeffries reminds us. It was relational. Eventually, if I recall correctly, it was swapped out for Essbase (the original MOLAP product, now owned by Oracle).
What Childs really focuses on, however, seems to be “Extended Set Theory.” (This was brought to my attention by Algebraix, even though Algebraix doesn’t actually use many of Childs’ ideas.) And he’s been doing it for a long time. Way back in 1968, Childs wrote a paper outlining how set theory, relations, and tuples could be applied to data management.
And that’s where I did a double-take, because 1968 < 1970. Sure enough, Footnote #1 in Codd’s seminal paper is to Childs’ 1968 work. Indeed, Childs’ paper is the only predecessor Codd acknowledges as having significant portions of his idea.
I’m far from convinced that “Extended set theory” has much to offer versus the standard relational model. But that debate quite aside — Childs’ original achievement doesn’t get the credit it deserves.