lance-format / lance-format/lance

Differentiate between NaN, infinite with ZoneMap filter

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A-index enhancement
Dominant language
Rust
Stars
7.1k
Forks
852
Avg merge
3d 18h
Merged PRs (30d)
272

Description

The incoming ZoneMap filter uses the DataFusion accumulator to calculate min/max which follows total ordering

Say we have an array of [NaN, 0.0, 3.0, 2.0, 1.0, 5.0], the max will be set to NaN rather than 5.0 which is les than ideal. If a lot of zones have the NaN value, the zonemap filter will become inefficient.

We should further improve the categorization for these special values to achieve optimal performance.

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First steps

  1. Read the whole issue, then the project's contributing guide.
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  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start by tracing the incoming ZoneMap filter and the DataFusion accumulator used to calculate min/max. Reproduce the array containing NaN, then define and verify separate categorization for NaN and infinite values so zones can be filtered efficiently.

Written by the indexing model from the issue text.

Assessment

Tech stack
rust
Domain
databases
Issue type
Feature
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

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