[LUCENE-9952] FacetResult#value can be inaccurate in SortedSetDocValueFacetCounts

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 9.0
• Fix Version/s: 9.1
• Component/s: modules/facet
• Lucene Fields: New
• Assignee: Greg Miller
• Reporter: Greg Miller
• Created: 10/May/21 16:33
• Updated: 28/Aug/22 16:21
• Resolved: 25/Jan/22 20:31

Description

As described in a dev@ list thread, the value of FacetResult#value can be incorrect in SSDV faceting when docs are multi-valued (affects both SortedSetDocValueFacetCounts and ConcurrentSortedSetDocValueFacetCounts). If a doc has multiple values in the same dimension, it will be counted multiple times when populating the counts of FacetResult#value.

We should either provide an accurate count, or provide -1 if we don't have an accurate count (like we do in taxonomy faceting). I think this change will be a bit involved though as SSDV facet counting likely needs to be made aware of FacetConfig.

NOTE: I've updated this description to describe only the SSDV case after spinning off LUCENE-9953 to track the LongValueFacetCounts case.

Issue Links

• links to: GitHub Pull Request #611
• links to: GitHub Pull Request #621