Feed Selection Options

I'm only currently importing one feed of about 40,000+ products into my website, and want to know how I can pull out the categories from that feed and use them as the categories on my website.

Is it possible to pull out single columns of results from just one datafeed? Or even be able to filter out by a keyword within that feed?

Thanks

you can filter on import ( affiliatefeeds.nl/callbacks.html ) and during display ( tab filters in the menu configuration)

the first method results in a smaller database thus faster.