system variables: document tidb_opt_index_join_build_v2 compat by qiancai · Pull Request #22739 · pingcap/docs · GitHub
Skip to content

system variables: document tidb_opt_index_join_build_v2 compat#22739

Open
qiancai wants to merge 1 commit intopingcap:masterfrom
qiancai:docs-index-join-build-v2-compat-21434
Open

system variables: document tidb_opt_index_join_build_v2 compat#22739
qiancai wants to merge 1 commit intopingcap:masterfrom
qiancai:docs-index-join-build-v2-compat-21434

Conversation

@qiancai
Copy link
Copy Markdown
Collaborator

@qiancai qiancai commented Apr 13, 2026

What is changed, added or deleted? (Required)

Document the compatibility behavior of tidb_opt_index_join_build_v2.

  • Add the system variable entry in system-variables.md.
  • Clarify that TiDB always uses index join build v2 now.
  • Clarify that setting this variable to OFF returns an error and cannot switch back to v1.
  • Clarify that historical values left in mysql.global_variables after upgrade are still treated as ON.
  • Add the corresponding entry to system-variable-reference.md.

Which TiDB version(s) do your changes apply to? (Required)

  • master (the latest development version)
  • v9.0 (TiDB 9.0 versions)
  • v8.5 (TiDB 8.5 versions)
  • v8.1 (TiDB 8.1 versions)
  • v7.5 (TiDB 7.5 versions)
  • v7.1 (TiDB 7.1 versions)
  • v6.5 (TiDB 6.5 versions)
  • v6.1 (TiDB 6.1 versions)
  • v5.4 (TiDB 5.4 versions)

What is the related PR or file link(s)?

Do your changes match any of the following descriptions?

  • Delete files
  • Change aliases
  • Need modification after applied to another branch
  • Might cause conflicts after applied to another branch

@qiancai qiancai added translation/from-docs-cn This PR is translated from a PR in pingcap/docs-cn. v9.0-beta.3 This PR/issue applies to TiDB v9.0-beta.3. labels Apr 13, 2026
@ti-chi-bot ti-chi-bot Bot added the size/XS Denotes a PR that changes 0-9 lines, ignoring generated files. label Apr 13, 2026
Copy link
Copy Markdown
Contributor

@gemini-code-assist gemini-code-assist Bot left a comment

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Code Review

This pull request adds a placeholder file named temp.md. The reviewer noted that this file should be removed as it does not contain the documentation for tidb_opt_index_join_build_v2 mentioned in the pull request description, and suggested placing the documentation in the correct system variable files instead.

I am having trouble creating individual review comments. Click here to see my feedback.

temp.md (1)

low

This file appears to be a placeholder and does not contain the documentation for tidb_opt_index_join_build_v2 as described in the pull request title and description. Remove this file and include the documentation in the appropriate files (system-variables.md and system-variable-reference.md).

References
  1. The documentation should be complete and accurate, covering all aspects described in the pull request summary. (link)

Synced from: pingcap/docs-cn#21434
Target PR: pingcap#22739
AI Provider: azure

Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
@github-actions
Copy link
Copy Markdown
Contributor

@github-actions github-actions Bot force-pushed the docs-index-join-build-v2-compat-21434 branch from 95eb41e to 691df73 Compare April 13, 2026 04:02
@ti-chi-bot
Copy link
Copy Markdown

ti-chi-bot Bot commented Apr 13, 2026

@ti-chi-bot ti-chi-bot Bot added size/S Denotes a PR that changes 10-29 lines, ignoring generated files. and removed size/XS Denotes a PR that changes 0-9 lines, ignoring generated files. labels Apr 13, 2026
@qiancai qiancai self-assigned this Apr 17, 2026
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Labels

size/S Denotes a PR that changes 10-29 lines, ignoring generated files. translation/from-docs-cn This PR is translated from a PR in pingcap/docs-cn. v9.0-beta.3 This PR/issue applies to TiDB v9.0-beta.3.

Projects

None yet

Development

Successfully merging this pull request may close these issues.

1 participant