MySQL, initially.

Later replaced with Oracle. Which Rob dissed thoroughly. Be interested to know Perrin's take on that -- better or worse or just different? Scuttlebut was that Oracle didn't like the fact that one of the top ten ecommerce sites wasn't running O.

Perrin wouldn't have been the only person to call it that either, regarding the other comment. OS/Z was in the process of shedding most of the original code as well. Definitely not built for collaborative development, nor was the initial developer minded to cooperate.

Edits: name fix

MySQL was principally "just a data store". There was relatively little reliance on higher-end database functions, and performance was at a premium. The claim was also that transactional integrity was provided through OM itself.

Then again, I keep my salt-sack open when considering Rob's dictums. I've caught him at several times at really major fibs. E.g.: Linux doesn't do networking at runlevel zero, Molar volume is a (practically) constant number of molecules of gas at constant T & P. Given his background -- graduate biology w/ significant chemistry, and years of Linux programming and admin -- he really should have known these. Worst, he was insistant on being wrong.