ERROR: No one parent tuple was found

Hi,

I got error when running vacuum analyze:

discovery=> vacuum analyze;
ERROR: No one parent tuple was found
discovery=>
discovery=> vacuum analyze hits;
NOTICE: CreatePortal: portal <vacuum> already exists
ERROR: No one parent tuple was found

postgres 6.5.3, Linux x86

Everything seems work fine. How dangerous this error ?
I got it for the first time since project was started about 6 months ago -
vacuuming runs in background every hour.

Hmm, now vacuum works. I just restart psql.

Oleg
_____________________________________________________________
Oleg Bartunov, sci.researcher, hostmaster of AstroNet,
Sternberg Astronomical Institute, Moscow University (Russia)
Internet: oleg(at)sai(dot)msu(dot)su, http://www.sai.msu.su/~megera/
phone: +007(095)939-16-83, +007(095)939-23-83