tableInfo: add more fields to make sharing schema more strictly

[hongyunyan]

What problem does this PR solve?

Issue Number: close #3911

What is changed and how it works?

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

Questions

Will it cause performance regression or break compatibility?

Do you need to update user documentation, design documentation or monitoring documentation?

Release note

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Summary by CodeRabbit

• Bug Fixes

  • Fixed schema comparison logic to properly account for index column prefix lengths. Schemas with different column prefix lengths are now correctly treated as distinct, improving cache behavior and schema handling accuracy.

• Tests

  • Added test case for schema caching with different index column lengths.

[gemini-code-assist]

Summary of Changes

Hello @hongyunyan, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request enhances the robustness of schema sharing by incorporating index column length into both the schema's unique identifier (digest) and its equality comparison logic. This change is crucial for preventing unintended schema sharing between tables that might otherwise appear similar but have different index prefix lengths, which could lead to incorrect primary key handle decoding, especially in scenarios involving clustered primary keys.

Highlights

• Schema Hashing: The hashTableInfo function now includes the col.Length of index columns in its digest calculation. This ensures that tables with different index prefix lengths will generate distinct schema digests, preventing incorrect schema sharing.
• Schema Equality Check: The sameColumnsAndIndices method has been updated to compare the col.Length of index columns. This makes schema equality checks stricter, preventing tables with differing index prefix lengths from being considered identical.
• New Test Case: A new test, TestGetOrSetColumnSchema_DifferentIndexColumnLength, was added to validate that schemas with different index column lengths are correctly identified as distinct, confirming the enhanced strictness of schema management.

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Changelog

• pkg/common/table_info_helper.go
  • Included index column length in the hashTableInfo digest calculation to ensure unique identification for schemas with varying index prefix lengths.
  • Added index column length comparison to sameColumnsAndIndices for stricter schema equality checks, preventing mismatches in handle decoding.
• pkg/common/table_info_helper_test.go
  • Added TestGetOrSetColumnSchema_DifferentIndexColumnLength to verify that schemas with differing index column lengths are correctly treated as distinct, validating the new schema comparison logic.

Activity

• No activity has been recorded for this pull request yet.

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[coderabbitai]

📝 Walkthrough

Walkthrough

The changes extend hashing and schema-equality logic in table info helpers to account for the length (prefix length) of index columns. This ensures schemas with different index column lengths are properly distinguished and not incorrectly shared.

Changes

Cohort / File(s)	Summary
Index Column Length Handling pkg/common/table_info_helper.go	Updated hashTableInfo to include column Length in hash calculations after Offset; modified sameColumnsAndIndices to require matching Length values for index columns when comparing schemas. Added clarifying comments on prefix length influence.
Test Coverage pkg/common/table_info_helper_test.go	Added TestGetOrSetColumnSchema_DifferentIndexColumnLength to verify that schemas with identical base columns but different index column lengths are treated as distinct, resulting in separate cached schemas with different Digest values.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~12 minutes

Suggested labels

lgtm, approved

Suggested reviewers

• wk989898
• lidezhu

Poem

🐰 Hops with glee at lengths now weighed,
No more shall schemas be mislaid,
Each index column's prefix clear,
Correctness blooms throughout the year! ✨

🚥 Pre-merge checks | ✅ 2 | ❌ 3

❌ Failed checks (2 warnings, 1 inconclusive)

Check name	Status	Explanation	Resolution
Description check	⚠️ Warning	The description includes the required issue reference but lacks details on what changed and how it works; most sections are left as empty template.	Add a 'What is changed and how it works?' section explaining the index column length addition; answer the checklist questions about compatibility and documentation needs.
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.
Linked Issues check	❓ Inconclusive	The PR implementation addresses part of issue #3911 by including index column length in hashing and equality checks, but does not fully address all stated objectives.	Verify whether PKIsHandle, IsCommonHandle, and index state have also been added to the digest calculation as required by issue #3911, or clarify if the PR scope is intentionally narrower.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately reflects the main change: adding index column length to schema hashing and equality checks to make schema sharing stricter.
Out of Scope Changes check	✅ Passed	All changes relate to the primary objective of improving schema sharing correctness through enhanced hashing and equality checks.

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[gemini-code-assist]

Code Review

This pull request enhances the strictness of schema sharing by incorporating the index column prefix length into the schema digest calculation and equality checks. The changes in pkg/common/table_info_helper.go correctly add col.Length to both hashTableInfo and sameColumnsAndIndices functions. This ensures that tables with different index prefix lengths are not considered to have the same schema, preventing potential issues with handle decoding. A new unit test, TestGetOrSetColumnSchema_DifferentIndexColumnLength, has been added to pkg/common/table_info_helper_test.go to verify this new behavior, confirming that different schemas and digests are generated as expected. The changes are correct and well-tested.

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: wk989898

The full list of commands accepted by this bot can be found here.

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Details

Needs approval from an approver in each of these files:

• OWNERS [wk989898]

Approvers can indicate their approval by writing /approve in a comment
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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2026-02-11 07:41:56.337304989 +0000 UTC m=+4269.417295684: ☑️ agreed by wk989898.