statistics: fix the error that init stats might got failure when decoding column bucket (#55685)

[ti-chi-bot]

This is an automated cherry-pick of #55685

…

What problem does this PR solve?

Issue Number: close #55684

Problem Summary:

What changed and how does it work?

The old init stats doesn't handle the collation string.

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

Attention: Patch coverage is 31.25000% with 22 lines in your changes missing coverage. Please review.

Please upload report for BASE (release-6.5@1097ba8). Learn more about missing BASE report.

Additional details and impacted files

@@               Coverage Diff                @@
##             release-6.5     #56024   +/-   ##
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  Coverage               ?   74.0206%           
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  Files                  ?       1097           
  Lines                  ?     355270           
  Branches               ?          0           
================================================
  Hits                   ?     262973           
  Misses                 ?      75598           
  Partials               ?      16699           

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: time-and-fate, winoros

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• OWNERS [time-and-fate,winoros]

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-09-12 08:26:25.587128283 +0000 UTC m=+517655.327552214: ☑️ agreed by winoros.
• 2024-09-12 08:53:47.667049208 +0000 UTC m=+519297.407473145: ☑️ agreed by time-and-fate.

[hawkingrei]

/retest