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Toke Eskildsen commented on LUCENE-3079: ---------------------------------------- This is quite another design than the quarter-baked one I've proposed with SOLR-2412 (which is really just a thin wrapper around LUCENE-2369). While maintaining a sidecar index makes the workflow more complicated, I would expect that it is beneficial for re-open speed and scalability. Technical note: For hierarchical faceting, I find that it is possible to avoid storing all levels in the hierarchy. By maintaining two numbers for each tag, denoting the tag-level and the level for the previous tag that matches, only the relevant tags needs to be indexed (full explanation at https://sbdevel.wordpress.com/2010/10/05/fast-hierarchical-faceting/). Kudos for contributing solid code. I am looking forward to seeing the patch. > Facetiing module > ---------------- > > Key: LUCENE-3079 > URL: https://issues.apache.org/jira/browse/LUCENE-3079 > Project: Lucene - Java > Issue Type: Improvement > Reporter: Michael McCandless > Attachments: LUCENE-3079.patch > > > Faceting is a hugely important feature, available in Solr today but > not [easily] usable by Lucene-only apps. > We should fix this, by creating a shared faceting module. > Ideally, we factor out Solr's faceting impl, and maybe poach/merge > from other impls (eg Bobo browse). > Hoss describes some important challenges we'll face in doing this > (http://markmail.org/message/5w35c2fr4zkiwsz6), copied here: > {noformat} > To look at "faceting" as a concrete example, there are big the reasons > faceting works so well in Solr: Solr has total control over the > index, knows exactly when the index has changed to rebuild caches, has a > strict schema so it can make sense of field types and > pick faceting algos accordingly, has multi-phase distributed search > approach to get exact counts efficiently across multiple shards, etc... > (and there are still a lot of additional enhancements and improvements > that can be made to take even more advantage of knowledge solr has because > it "owns" the index that we no one has had time to tackle) > {noformat} > This is a great list of the things we face in refactoring. It's also > important because, if Solr needed to be so deeply intertwined with > caching, schema, etc., other apps that want to facet will have the > same "needs" and so we really have to address them in creating the > shared module. > I think we should get a basic faceting module started, but should not > cut Solr over at first. We should iterate on the module, fold in > improvements, etc., and then, once we can fully verify that cutting > over doesn't hurt Solr (ie lose functionality or performance) we can > later cutover. -- This message is automatically generated by JIRA. For more information on JIRA, see: http://www.atlassian.com/software/jira --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For additional commands, e-mail: dev-h...@lucene.apache.org