expression: resolve bug caused by CAST during expression rewriting in compare subquery

[dash12653]

What problem does this PR solve?

Issue Number: close #50785

Problem Summary:

What changed and how does it work?

Update rexpr when a cast function is necessary before building compare condition.
As discussed in #50785.

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

[ti-chi-bot]

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[ti-chi-bot]

Hi @dash12653. Thanks for your PR.

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[tiprow]

Hi @dash12653. Thanks for your PR.

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[dash12653]

Hi @elsa0520 @wjhuang2016 Could you please review this PR when you get a chance? Thank you!

[wjhuang2016]

@winoros PTAL