null PRs

Hi
I've deleted about one hundred PRs (test and other rubbish) directly 
from my database folders. Now when I submit a query I can see the 
same number of empty PRs at the beginning of my search result list. I 
can't edit these empty lines ("Error, you must specify a problem 
report number") . I tried to run "gen-index -d" and "check-db -d" but 
it didn't help. How to get rid of these empty PRs? Can I access gnats 
databases directly with sql?
Cheers
Adam