planner: fix cost adjustment for high risk tablescan (#57086)

[ti-chi-bot]

This is an automated cherry-pick of #57086

What problem does this PR solve?

Issue Number: close #57085

Problem Summary:

What changed and how does it work?

Code to provide a minimum cost to table scan - should use "max" rather than "min" to ensure that the minimum is actually applied. Current code will produce a lower cost for tablescans greater than 1000 rows that fit the other criteria for requiring a minimum cost to table scans.

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

All modified and coverable lines are covered by tests ✅

Please upload report for BASE (release-8.5@4fb27d5). Learn more about missing BASE report.

Additional details and impacted files

@@               Coverage Diff                @@
##             release-8.5     #57190   +/-   ##
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  Coverage               ?   56.3352%           
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  Files                  ?       1778           
  Lines                  ?     635030           
  Branches               ?          0           
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  Hits                   ?     357746           
  Misses                 ?     253117           
  Partials               ?      24167           

Flag	Coverage Δ
integration	37.0600% <100.0000%> (?)
unit	72.4914% <100.0000%> (?)

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

Components	Coverage Δ
dumpling	52.9478% <0.0000%> (?)
parser	∅ <0.0000%> (?)
br	52.6516% <0.0000%> (?)

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: hawkingrei, qw4990

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-11-07 03:32:03.811340561 +0000 UTC m=+1098236.650496092: ☑️ agreed by hawkingrei.
• 2024-11-07 03:32:19.123056318 +0000 UTC m=+1098251.962211861: ☑️ agreed by qw4990.