Added EXPLAIN FORMAT="cost_trace" (#21898)

[ti-chi-bot]

This is an automated cherry-pick of #21898

close #21897

What is changed, added or deleted? (Required)

Added cost_trace as EXPLAIN FORMAT

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[gemini-code-assist]

Summary of Changes

Hello @ti-chi-bot, 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 EXPLAIN statement functionality by adding a new cost_trace format. This new format is designed to provide users with more granular details about the estimated cost of query execution and the specific formulas used to calculate these costs, thereby aiding in advanced query optimization and performance analysis.

Highlights

• New EXPLAIN FORMAT: Introduced cost_trace as a new format option for the EXPLAIN statement. This format provides additional columns, estCost for the estimated cost and costFormula for the underlying cost formula, offering deeper insights into query plan costs.

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[gemini-code-assist]

Code Review

This pull request adds documentation for the cost_trace format in the EXPLAIN statement. The change is straightforward. I've suggested a minor wording improvement to enhance clarity and adhere to the documentation style guide by ensuring all code-like elements are properly formatted and avoiding repetition.

[hfxsd]

/approve

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: hfxsd

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