[ti-chi-bot]

This is an automated cherry-pick of #12675

What problem does this PR solve?

Issue Number: ref #12350

What is changed and how it works?

Support DM FK causality when foreign_key_checks=1 and syncer.worker-count > 1 with static one-to-one route rules.

This PR:

• builds FK causality relations with source table identity after route validation
• makes causality key generation follow the task case-sensitive setting, including routed FK causality keys
• respects the task case-sensitive setting when matching FK metadata and checking route topology
• rejects route rules that map multiple source tables in the task to the same target table
• rejects compact and multiple-rows DML boundary options when foreign_key_checks=1
• caches successful route topology checks and invalidates the cache after schema/config state changes
• adds unit and integration test coverage for routed multi-worker FK causality

A follow-up PR will explicitly reject hot updates that can change route/filter/case-sensitive/FK causality mode.

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

Questions

Will it cause performance regression or break compatibility?

Do you need to update user documentation, design documentation or monitoring documentation?

Release note

Support foreign key causality for static one-to-one routing in DM multi-worker sync.

[ti-chi-bot]

@OliverS929 This PR has conflicts, I have hold it.
Please resolve them or ask others to resolve them, then comment /unhold to remove the hold label.

[ti-chi-bot]

@ti-chi-bot: ## If you want to know how to resolve it, please read the guide in TiDB Dev Guide.

Details

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the ti-community-infra/tichi repository.

[gemini-code-assist]

Code Review

This pull request introduces support for foreign key (FK) causality in one-to-one routing scenarios within DM. It adds task-level route topology validation, case-insensitive table identity matching, and causality key generation adjustments. However, the pull request contains several critical issues that must be addressed: multiple unresolved git conflict markers are present across several configuration, test, and error definition files. Additionally, there are several potential nil pointer dereference panics in sameForeignKeyTableIdentity, causalityKeySourceTableNameForRowChange, and foreignKeyRouteTopologyTableID that require defensive nil checks.

Important

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For more details on the timeline and next steps, please review the Help Documentation.

[codecov]

Codecov Report

❌ Patch coverage is 94.28571% with 10 lines in your changes missing coverage. Please review.
⚠️ Please upload report for BASE (release-8.5@01a951d). Learn more about missing BASE report.

Additional details and impacted files

Components	Coverage Δ
cdc	57.5924% <0.0000%> (?)
dm	49.3679% <0.0000%> (?)
engine	50.7050% <0.0000%> (?)

Flag	Coverage Δ
cdc	57.5924% <90.0000%> (?)
unit	53.5566% <94.2857%> (?)

Flags with carried forward coverage won't be shown. Click here to find out more.

@@               Coverage Diff                @@
##             release-8.5     #12707   +/-   ##
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  Lines                  ?     138108           
  Branches               ?          0           
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[OliverS929]

/retest

[OliverS929]

/unhold

[ti-chi-bot]

@OliverS929: adding LGTM is restricted to approvers and reviewers in OWNERS files.

Details

In response to this:

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository.

[Benjamin2037]

LGTM

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Benjamin2037, OliverS929, yudongusa

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Details

Needs approval from an approver in each of these files:

• OWNERS [Benjamin2037]
• dm/OWNERS [Benjamin2037]
• dm/config/OWNERS [yudongusa]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[wuhuizuo]

/check-cla