expression: simplify the code with the ExtractColumnsFromExpressions (#62825)

[ti-chi-bot]

This is an automated cherry-pick of #62825

What problem does this PR solve?

Issue Number: ref https://github.com/pingcap/tidb/issues/63810

Problem Summary:

What changed and how does it work?

ExtractColumnsFromExpressions has been able to remove duplicates. In this PR, we enhence this function to make it reusing the memory and avoid allocating the slices.

Check List

Tests

• [x] Unit test
• [ ] Integration test
• [ ] Manual test (add detailed scripts or steps below)
• [ ] No need to test

  • [ ] I checked and no code files have been changed.

Side effects

• [ ] Performance regression: Consumes more CPU
• [ ] Performance regression: Consumes more Memory
• [ ] Breaking backward compatibility

Documentation

• [ ] Affects user behaviors
• [ ] Contains syntax changes
• [ ] Contains variable changes
• [ ] Contains experimental features
• [ ] Changes MySQL compatibility

Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

None

[ti-chi-bot]

@hawkingrei This PR has conflicts, I have hold it. Please resolve them or ask others to resolve them, then comment /unhold to remove the hold label.

[ti-chi-bot[bot]]

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[codecov[bot]]

Codecov Report

:x: Patch coverage is 91.66667% with 12 lines in your changes missing coverage. Please review. :warning: Please upload report for BASE (release-8.5@f5289a7). Learn more about missing BASE report.

Additional details and impacted files

@@               Coverage Diff                @@
##             release-8.5     #64781   +/-   ##
================================================
  Coverage               ?   76.6178%           
================================================
  Files                  ?       1672           
  Lines                  ?     463661           
  Branches               ?          0           
================================================
  Hits                   ?     355247           
  Misses                 ?      86765           
  Partials               ?      21649           

Flag	Coverage Δ
integration	49.7080% <89.5833%> (?)

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
dumpling	52.9278% <0.0000%> (?)
parser	∅ <0.0000%> (?)
br	57.1951% <0.0000%> (?)

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[ti-chi-bot[bot]]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: hawkingrei Once this PR has been reviewed and has the lgtm label, please assign windtalker for approval. For more information see the Code Review Process. Please ensure that each of them provides their approval before proceeding.

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[ti-chi-bot[bot]]

[LGTM Timeline notifier]

Timeline:

• 2025-12-12 10:18:35.457001343 +0000 UTC m=+1209060.270778915: :ballot_box_with_check: agreed by hawkingrei.

[EmmaDuDu]

/test unit-test

[tiprow[bot]]

@EmmaDuDu: No presubmit jobs available for pingcap/[email protected]

In response to this:

/test unit-test

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[ti-chi-bot[bot]]

@ti-chi-bot: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
idc-jenkins-ci-tidb/unit-test	61a535f9365fc4e91f0003a0e814c337b8a10ec2	link	true	/test unit-test

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