I like Skip's version better, because it's closer to the dbm
"specification" instead of trying to mimic bsddb (first, last, etc.).
I'd like to keep such things out.

I've made a few changes to the sandbox project which I will check in
later today. The most important change is support for a "fast mode",
which doesn't commit changes until you call the synch() method. synch()
is also called on close().

Perhaps we should do automatic commits every n (like 1000) changes, too?

What's all this ORDER BY in both your implementations about? The dbm
"spec" says nothing about keys being ordered AFAIC. Can we get rid of these?