[LUCENE-10122] Explore using NumericDocValue to store taxonomy parent array

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 9.0
• Fix Version/s: 9.0, 10.0 (main)
• Component/s: modules/facet
• Lucene Fields: New
• Assignee: Unassigned
• Reporter: Patrick Zhai
• Created: 24/Sep/21 22:39
• Updated: 28/Aug/22 16:26
• Resolved: 19/Nov/21 21:21

Description

We currently use term position of a hardcoded term in a hardcoded field to represent the parent ordinal of each taxonomy label. That is an old way and perhaps could be dated back to the time where doc values didn't exist.

We probably would want to use NumericDocValues instead given we have spent quite a lot of effort optimizing them.

Issue Links

• links to: GitHub Pull Request #420
• links to: GitHub Pull Request #442
• links to: GitHub Pull Request #451
• links to: GitHub Pull Request #454
• links to: GitHub Pull Request #458