No, it does not. But the version of db included in the Racket development tree (and soon, 5.2) has an option to use places to avoid blocking all Racket threads. Ryan <div style="font-family: arial, sans-serif; font-size: 12px;color: #999999">-- Sent from my HP TouchPad</div><hr align="left" style="width:75%">On Nov 9, 2011 12:16 PM, YC <yinso.chen@gmail.com> wrote: Hi all - does anyone know whether the ODBC driver in ryanc/db.plt (I am aware it's FFI-based) goes around the limitation of FFI calls serialize all racket threads?  Thanks, yc