Long story short: I did something daft with a module's db table (Forward module, if anyone's interested)

I tried to manually recreate the tables but am obviously missing something as I'm getting sql errors all over the site when I try to utilize the module. So I just want to go back to scratch and start again.

When I got into this difficulty, I deleted all the Forward module files AND deleted both db tables, forward_log and forward_statistics. And got ready to start from zero.

Yet, when I uploaded the module again and activated it, the forward.install fine evidently didn't run and there were no new tables added to the db. Is there something, some flag, elsewhere on the db that tells the system the tables have already been created and there's no need to do it again?? If so, how do I switch it off/delete a value to allow forward.install to run again?

Neil