delta-io/delta

[Kernel] Validate readSchema is a subset of the table schema in ScanBuilder

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#2,149 opened on Oct 6, 2023

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 (5 comments) (0 reactions) (1 assignee)Scala (2,100 forks)batch import
enhancementgood first issuekernel

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Description

Feature request

Which Delta project/connector is this regarding?

  • Spark
  • Standalone
  • Flink
  • Kernel
  • Other (fill in here)

Overview

Validate that the read schema provided in ScanBuilder is a subset of the snapshot schema. https://github.com/delta-io/delta/blob/master/kernel/kernel-api/src/main/java/io/delta/kernel/internal/ScanBuilderImpl.java#L80

Motivation

Better validation / error messages.

Contributor guide

Research direction
Examine ScanBuilderImpl.java to understand how readSchema is currently set and validate it as a subset of the table snapshot schema using existing schema utilities.
Tech stack
java
Domain
backenddatabase
Issue type
Feature
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
Half day
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
JavaDelta Kernel concepts
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
60