I was doing some speed tests of the BPT engine on Mac OS X Tiger, which ships with SQLite 3.1.3.  I accidentally built Emdros against the SQLite 3 that ships with Tiger, and found that GET OBJECTS HAVING MONADS IN was painfully slow. It took up to 10 minutes to run a basic query.

I found out that SQLite 3.1.3 doesn't have some optimizations for column_name BETWEEN X AND Y which are present in later versions of SQLite 3.  GET OBJECTS HAVING MONADS IN makes heavy use of precisely this construct.

So I changed all cases of this construct to the idiom "column_name >= X AND column_name <= Y". This has no noticeable side-effects on the speed on Linux, but does give a great increase in speed on Mac OS X.

Still, BPT beats SQLite 3 by a wide margin: 270 seconds for SQLite 3, 214 seconds for BPT, to run all test-queries in one of my test suites (124 queries against a syntactic database of 1.4 million syntactic objects). That's a 20% speed increase on this particular combination of harware and Mac OS X 10.4. (The hardware is a 2007 Mac Mini, Intel Core Duo 1.6GHz, 1GB Ram).

Ulrik