Claudio Ranieri and I briefly discussed collator based sorting for facets in the thread "Problem with accented words sorting" on the solr-user mailing list. Here's the idea:
Solr faceting supports sorting by either count or index order. Claudio and I both need the order to be collator-based. My understanding of the issue is that it is not currently possible. Collator-based document sorting in Solr uses CollationKeys as field values. This does not work with faceting on fields with multiple values as there is no mapping from the key to the human readable value. ICU sort keys are always null (00) terminated and when two keys are compared, the comparison stops as soon as null is reached(?) http://userguide.icu-project.org/collation/architecture If we concatenate the keys with the original values: <key><00><original value><offset of original value> we get an entity where the ordering is still correct upon comparison and where the original value can be extracted by using the offset from the last int (or maybe short, to spare 2 bytes) in the BytesRef. If the idea is sound, I'll open a JIRA issue. Unfortunately I do not have time right now for hacking on it. --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For additional commands, e-mail: dev-h...@lucene.apache.org
