Outdated data - how do I reset the QS database?

[JohnnytheHeat]

Hi folks,
I moved the bulk of my documents into my Shared folder several months
ago, but items in the old locations still appear in QS. Usually I get
the old 'ghost' item at the top of the list, then some way down I see
the item in it's correct new place.
I'd like to just trash the catalog (I think) and rescan the mac. I
dont want to lose my custom triggers etc though. Any advice?