[LUCENE-7744] default value for scoring payloads

• Type: New Feature
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 7.2
• Component/s: core/query/scoring
• Lucene Fields: New, Patch Available
• Assignee: Erik Hatcher
• Reporter: Nathan Gass
• Created: 13/Mar/17 13:16
• Updated: 28/Aug/22 15:12
• Resolved: 13/Nov/17 12:16

Description

In lucene 5, PayloadTermQuery used a hardcoded default of 1.0 for terms without a payload. The replacing PayloadScoreQuery in lucene 6 just ignores those terms. This is unflexible and wrong for many use cases (for example using Payloads to deemphasize some terms, where terms without payload should result in maximum score instead of being ignored).

In my pull request I defer the decision on what to do with missing payloads to the scorePayload method of the similarity, which has to check the given payload for null and handle that case. I believe this breaks backwards compatibility?

Issue Links

• Is contained by: LUCENE-8038 Decouple payload decoding from Similarity
• links to: GitHub Pull Request #167