In a large number of implementations which I took part in, sooner or later, the question arise – what can we do to get faceting as a tree structure. Of course there some tricks for that, however, their use was to modify the data and appropriate processing of the results on application side. It was not particularly functional, nor especially comfortable. However, a few days ago Solr version 4.0 has been enhanced with code that is marked as Solr-792 in the system JIRA. Let’s see in this case, how to get the faceting results as a tree.
grouping
Quick look – FieldCollapsing
FieldCollapsing, or in other words grouping of search results has just been commited to the svn repository. I decided to take a look at this functionality and see how it works.