ddl: supports non-unique global index (#58678)

[ti-chi-bot]

This is an automated cherry-pick of #58678

What problem does this PR solve?

Issue Number: close #58650

Problem Summary: Supports non-unqiue global index. Not found bugs right now, we will add more test cases later.

What changed and how does it work?

Check List

Tests

• 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

[codecov]

Codecov Report

❌ Patch coverage is 90.00000% with 1 line in your changes missing coverage. Please review.
⚠️ Please upload report for BASE (release-8.5@1336d40). Learn more about missing BASE report.

Additional details and impacted files

@@               Coverage Diff                @@
##             release-8.5     #63607   +/-   ##
================================================
  Coverage               ?   57.9075%           
================================================
  Files                  ?       1783           
  Lines                  ?     633663           
  Branches               ?          0           
================================================
  Hits                   ?     366939           
  Misses                 ?     242142           
  Partials               ?      24582           

Flag	Coverage Δ
integration	38.4100% <90.0000%> (?)
unit	72.9264% <70.0000%> (?)

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	63.4799% <0.0000%> (?)

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[bb7133]

LGTM

[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2025-09-19 02:47:34.325427948 +0000 UTC m=+154415.804008594: ☑️ agreed by Defined2014.
• 2025-09-19 03:10:09.405503147 +0000 UTC m=+155770.884083804: ☑️ agreed by bb7133.

[Benjamin2037]

LGTM

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: bb7133, Benjamin2037, Defined2014

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• OWNERS [Benjamin2037,Defined2014,bb7133]
• pkg/ddl/OWNERS [Benjamin2037]

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[Defined2014]

/retest

[Defined2014]

/retest

[Defined2014]

/retest