[Zope] Question about ZCatalog

Hello all, I'm just writing my first major Zope website, and I'm stuck with a (probably easy) question. My site consists of dtml-documents, ZSAL methods that access an Oracle database and some Local File Systems (using LocalFS). I want to add an option that enables the users to search through all this contents. My question now is: is ZCatalog the way to go, or do I need something else? I know I can use ZCatalog to search through the objects in the ZODB, but I'm not sure if you can use it to search through the results of ZSQLMethods or Local File Systems... If ZCatalog is the way to go, do I need to take care of special stuff? What I'm most concerned about are the LocalFS (as they are over 600MB of raw data). Kind regards, Pieter