sql: add note about table aliases in FOR UPDATE OF clause

[cryo-zd]

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Added a note about table aliases in the FOR UPDATE OF clause

ZH PR: pingcap/docs-cn#21489

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• Other reference link(s): planner: support table aliases in FOR UPDATE OF Clause tidb#65532

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[gemini-code-assist]

Summary of Changes

Hello, 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 enhances the TiDB documentation for the SELECT statement by incorporating crucial information about the handling of table aliases in the FOR UPDATE OF clause. The update specifically addresses changes introduced in TiDB v8.5.6, providing users with clear guidance on alias usage, ensuring backward compatibility, and explaining how the system resolves potential ambiguities in complex queries involving identically named tables across different databases.

Highlights

• Documentation Update for FOR UPDATE OF Clause: A new note has been added to the SELECT statement documentation, detailing the support for table aliases within the FOR UPDATE OF clause starting from TiDB v8.5.6. This note clarifies behavior regarding backward compatibility, warnings for using base table names when aliases are defined, and how ambiguity is resolved when multiple tables with the same name are involved.

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Changelog

• sql-statements/sql-statement-select.md
  • Added a detailed note explaining the new support for table aliases in the FOR UPDATE OF clause, effective from TiDB v8.5.6.
  • Included guidance on backward compatibility, the issuance of warnings when base table names are used with aliases, and the resolution mechanism for ambiguous table references.

Activity

• The author confirmed completion of the Contributor License Agreement.
• The changes are designated to be applied to the master, v9.0, and v8.5 branches of the documentation.

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All committers have signed the CLA.

[gemini-code-assist]

Code Review

This pull request adds a helpful note about the new support for table aliases in the FOR UPDATE OF clause. My review includes a suggestion to refine the wording for better clarity and consistency with the documentation style guide, particularly regarding the use of active voice and addressing the user directly.

[lilin90]

/ok-to-test

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[bb7133]

LGTM

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Timeline:

• 2026-04-01 02:57:38.477105695 +0000 UTC m=+320263.682465752: ☑️ agreed by hfxsd.