Existing Applications and Ferret

I’m building an application that will supplant an existing application
that’s up and running right now. I want to use Ferret (coupled with
Acts As Ferret) for searching, but I’m a bit bamboozled about a few
things. I was hoping for some advice.

  1. With Acts As Ferret, is it possible to restrict searches to children
    of an instance? For instance, suppose you have a database with a
    hundred schools, and each school had many students. I might want to
    search school “A”'s students, and only those students.

  2. What’s the best way to build an index for the existing database? Is
    it best for me to use a crawler like RDig, or should I just load data
    and then build the index manually using something like a Rake task?

  3. Is it wise to prune the Ferret index now and then?

Thank you.

James H.