faceted-search

I am planning on setting up a filter system (refine your search) in my ecommerce stores. You can see an example here: http://www.bettymills.com/shop/product/find/Air+and+HVAC+Filters Platforms such as PrestaShop, OpenCart and Magento have what's called a Layered Navigation. My question is what is the difference between the Layered Navigation in platforms such as Magento or PrestaShop in comparison to using something like Solr or Lucene for faceted navigation. Can a similar result be accomplished via just php and mysql? A detailed explanation is much appreciated. Layered Navigation == Faceted

What exactly is faceted search in the context of full-text search? I even read about it from Wikipedia , but I couldn't completely understand the use/benefit of it. Hope the community can answer/expand and explain with some good examples. NOTE: We're into the process of evaluating/researching different open search full-text search engine and mostly I'm seeing faceted search listed as one of the feature among others. So I'm trying to assess whether this would be helpful for our application requirement. Gnanam Faceted search is well-explained here and Lucene faceted through an example. EXAMPLE:

If a doc is listed as Book>Fiction>Sci-FI, it must be searchable when your facet query is "Book", "Book>Fiction", "Book>Fiction>Sci-fi". I searched the Internet and the methods I came up with are: 1 Split the "Book>Fiction>Sci-FI" into "Book", "Book>Fiction", "Book>Fiction>Sci-fi" at index-time itself and store them in same field . 2 Have separate fields cat, sub_cat, sub_sub_cat. Split the catogories into corresponding fields and use Pivot facets http://wiki.apache.org/solr/SimpleFacetParameters#Pivot_.28ie_Decision_Tree.29_Faceting What are other ways to do hierarchial facets, so that they