best practices: multi-column index optimization (#20955) #21269
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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 introduces new documentation to guide users on effectively utilizing multi-column indexes in TiDB for query optimization. The content delves into how TiDB's optimizer processes complex conditions to achieve significant performance improvements, providing practical examples and explanations of its internal mechanisms.
Highlights
- New Documentation Page: I've added a comprehensive new documentation page titled 'Best Practices for Optimizing Multi-Column Indexes'. This document explains the functionality, importance, and advanced optimization techniques for multi-column indexes in TiDB, including how the optimizer handles complex
ANDandORconditions. - Table of Contents Update: I've updated the
TOC.mdfile to include a link to the newly added 'Optimize Multi-Column Indexes' document under the 'Best Practices' section, making it easily discoverable for users. - TiDB Optimizer Insights: The new document provides detailed insights into TiDB's query optimizer, specifically its range derivation component, illustrating how it efficiently processes multi-column filters and complex row expressions, contrasting TiDB's capabilities with those of MySQL.
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Code Review
This pull request adds a new documentation page on best practices for multi-column index optimization. The content is well-structured and provides valuable insights. I've added a few comments to improve clarity, correct minor formatting issues in EXPLAIN outputs, and ensure consistency with the style guide. Overall, this is a great contribution.
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/approve |
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[APPROVALNOTIFIER] This PR is APPROVED This pull-request has been approved by: hfxsd The full list of commands accepted by this bot can be found here. The pull request process is described here
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This is an automated cherry-pick of #20955
First-time contributors' checklist
What is changed, added or deleted? (Required)
Which TiDB version(s) do your changes apply to? (Required)
Tips for choosing the affected version(s):
By default, CHOOSE MASTER ONLY so your changes will be applied to the next TiDB major or minor releases. If your PR involves a product feature behavior change or a compatibility change, CHOOSE THE AFFECTED RELEASE BRANCH(ES) AND MASTER.
For details, see tips for choosing the affected versions.
What is the related PR or file link(s)?
Do your changes match any of the following descriptions?