delta-io/delta

[Feature Request] Automatically generate partition filters for generated columns using the floor function

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#1,444 opened on Oct 18, 2022

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 (1 comment) (1 reaction) (0 assignees)Scala (2,100 forks)batch import
enhancementgood first issue

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Description

See #1442

We can automatically generated partition filters when a partition column is generated by the floor function.

i.e. if x < y then floor(x) <= floor(y)

Contributor guide

Research direction
Examine the existing partition filter generation logic in Delta Lake, specifically in the context of generated columns and the floor function. Identify where filter pushdown is implemented and extend it to infer that if x < y then floor(x) <= floor(y). Consider adding a new entry in SupportedGenerationExpressions.scala for floor and implement the corresponding filter generation in PartitionFiltering.scala.
Tech stack
scalaspark
Domain
backenddatabasedistributed systemsdata engineering
Issue type
Feature
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
4
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
3-5 days
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
ScalaApache SparkDelta Lake
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
30