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Shai Erera commented on LUCENE-4715: ------------------------------------ bq. so you get the gains of NO_PARENTS without the cost (end rollup) I'd like to clarify the difference between the 3 OrdinalPolicies, through example. Say that you add the facet Date/2010/March/11, then the ordinals that will be encoded are of: * ALL_PARENTS: Date, Date/2010, Date/2010/March, Date/2010/March/11 (4 ordinals) * NO_PARENTS: Date/2010/March/11 (1 ordinal) * ALL_BUT_DIMENSION: Date/2010, Date/2010/March, Date/2010/March/11 (3 ordinals) The aggregation of ALL_PARENTS and ALL_BUT_DIM is the same, but you don't get the count of Date/ with the latter policy. The aggregation of NO_PARENTS is the same as ALL_PARENTS, only you need to do the rollup in the end. Maybe we should have just ALL and ALL_BUT_DIM? Given the results of NO_PARENTS (not that significant gains), and the complexity involved (i.e. currently only CountingFC supports it) ... But I just wanted to clarify the differences, because the ALL_BUT_DIM is not that much different than ALL, except that you'll encode and decode the same ordinal for many documents, so that has got to buy us something ... > Add OrdinalPolicy.ALL_BUT_DIMENSION > ----------------------------------- > > Key: LUCENE-4715 > URL: https://issues.apache.org/jira/browse/LUCENE-4715 > Project: Lucene - Core > Issue Type: Improvement > Components: modules/facet > Reporter: Shai Erera > Assignee: Shai Erera > > With the move of OrdinalPolicy to CategoryListParams, > NonTopLevelOrdinalPolicy was nuked. It might be good to restore it, as > another enum value of OrdinalPolicy. > It's the same like ALL_PARENTS, only doesn't add the dimension ordinal, which > could save space as well as computation time. It's good for when you don't > care about the count of Date/, but only about its children counts. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators 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