add _tidb_rowid document

[tangenta]

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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 introduces a new document explaining the _tidb_rowid hidden column in TiDB, which is used as the row handle for tables without a clustered index. The PR also updates existing documentation to reference this new document, improving the overall clarity and completeness of the TiDB documentation.

Highlights

• Documentation Enhancement: This PR adds documentation for the _tidb_rowid hidden column in TiDB, explaining its usage, availability, and restrictions.
• TOC Updates: The table of contents (TOC) files have been updated to include the new _tidb_rowid documentation.
• Reference Updates: Existing documentation on clustered indexes and SHARD_ROW_ID_BITS has been updated to reference the new _tidb_rowid documentation.

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[gemini-code-assist]

Code Review

This pull request introduces comprehensive documentation for _tidb_rowid, a hidden system column in TiDB. The changes include a new dedicated page for _tidb_rowid and updates to several existing documents to link to this new page, improving discoverability and consistency. The new documentation is well-structured and provides valuable information. My review includes a few suggestions to enhance clarity and adhere to the documentation style guide, such as refining the summary, clarifying technical terms, and ensuring consistent formatting.

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by:
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[D3Hunter]

lgtm

[bb7133]

LGTM

[ti-chi-bot]

@bb7133: adding LGTM is restricted to approvers and reviewers in OWNERS files.

Details

In response to this:

LGTM

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[hfxsd]

/retest