Recover from a corrupt pkg DB

I had a crash while building ffmpeg on a new system. The build had not
begun, so I don't think ffmpeg is really an issue. portmaster(8) was
walking the dependency tree when the system panicked and, after a reboot
and full fsck, I get the error:
pkg: sqlite error while executing PRAGMA user_version; in file
pkgdb.c:2357: database disk image is malformed

Is there any way to rebuild the DB or, if not, how do I remove it and start
from scratch?
-- 
Kevin Oberman, Part time kid herder and retired Network Engineer
E-mail: rkoberman@gmail.com
PGP Fingerprint: D03FB98AFA78E3B78C1694B318AB39EF1B055683