change illegal to invalid

[hfxsd]

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[gemini-code-assist]

Summary of Changes

Hello @hfxsd, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request focuses on a significant terminology refinement within the documentation. The word "illegal" has been systematically replaced with "invalid" to provide more accurate and consistent language when referring to data, values, or operations that do not conform to expected rules or formats. This change enhances the precision of the documentation, making it clearer for users to understand error conditions and system behaviors.

Highlights

• Terminology Consistency: The term "illegal" has been consistently replaced with "invalid" across various documentation files to improve clarity and precision in describing data states or operations that are not permissible.
• Documentation Updates: Numerous documentation pages, including those related to character sets, SQL modes, literal values, and release notes, have been updated to reflect this terminology change.
• Impact on Specific Features: Changes affect descriptions of character compatibility (GBK), SQL mode behavior (ONLY_FULL_GROUP_BY, strict modes), handling of hexadecimal and bit-value literals, and various bug fixes mentioned in release notes concerning data types, memory access, and optimizer hints.

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[gemini-code-assist]

Code Review

This pull request consistently replaces the term "illegal" with "invalid" across numerous documentation files, which is a commendable effort to improve terminology consistency. The changes are mostly accurate and enhance the clarity of the documentation. I have identified a few areas for further improvement, including a suggestion for conciseness, a recommendation for further terminological consistency, and one instance where reverting to "illegal" would be more appropriate for the context. Overall, this is a valuable and well-executed documentation update.

[lilin90]

/lgtm

[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2025-11-18 10:19:25.441379572 +0000 UTC m=+6929.090574029: ☑️ agreed by lilin90.

[hfxsd]

/approve

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: hfxsd

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[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-8.5: #22065.