Having worked on a number of customer implementations regarding this feature I can say that the number one requirement is for the facet counts to be accurate post collapsing. It all comes down to the user experience. For example, if I run a query that get collapsed and has a facet count for the non-collapsed value then when I click on that facet for refinement the number of hits in my subsequent query will not match the number of hits displayed by that facet count. Ie if it says there are 10 docs in my result set of type x then when I click on type x I expect to get back 10 hits. Further, I could easily end up with a result set with 15 total hits but a facet count hat says there are 200 results of type x which is very disconcerting from a user perspective.
I agree that there are times when pre-faceting is also good, but post-faceting has always been a rather hard requirement for most ecommerce/data discovery sites. - will -----Original Message----- From: Emmanuel Keller (JIRA) [mailto:[EMAIL PROTECTED] Sent: Sunday, June 10, 2007 7:33 AM To: solr-dev@lucene.apache.org Subject: [jira] Commented: (SOLR-236) Field collapsing [ https://issues.apache.org/jira/browse/SOLR-236?page=com.atlassian.jira.p lugin.system.issuetabpanels:comment-tabpanel#action_12503162 ] Emmanuel Keller commented on SOLR-236: -------------------------------------- Do we have to make a choice ? Both behaviors are interesting. What about a new parameter like collapse.facet=[pre|post] ? > Field collapsing > ---------------- > > Key: SOLR-236 > URL: https://issues.apache.org/jira/browse/SOLR-236 > Project: Solr > Issue Type: New Feature > Components: search > Affects Versions: 1.2 > Reporter: Emmanuel Keller > Attachments: field_collapsing_1.1.0.patch, SOLR-236-FieldCollapsing.patch, SOLR-236-FieldCollapsing.patch > > > This patch include a new feature called "Field collapsing". > "Used in order to collapse a group of results with similar value for a given field to a single entry in the result set. Site collapsing is a special case of this, where all results for a given web site is collapsed into one or two entries in the result set, typically with an associated "more documents from this site" link. See also Duplicate detection." > http://www.fastsearch.com/glossary.aspx?m=48&amid=299 > The implementation add 3 new query parameters (SolrParams): > "collapse.field" to choose the field used to group results > "collapse.type" normal (default value) or adjacent > "collapse.max" to select how many continuous results are allowed before collapsing > TODO (in progress): > - More documentation (on source code) > - Test cases > Two patches: > - "field_collapsing.patch" for current development version (1.2) > - "field_collapsing_1.1.0.patch" for Solr-1.1.0 > P.S.: Feedback and misspelling correction are welcome ;-) -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.
