util: the incorrectly handle string compare with whitespace

[fanrenhoo]

What problem does this PR solve?

Issue Number: close #52938

Problem Summary: TiDB incorrectly handle the comparision of Strings with whitespace ending

What changed and how does it work?

In collation string compare functions, remove the TrimRightSpace(str) for Compare and Key funcs

Check List

Tests

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

  • I checked and no code files have been changed.

Side effects
No

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation
No

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

Fix the issue that in expression the comparision of strings with whitespaces padding will be treated as same

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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[ti-chi-bot]

Hi @fanrenhoo. Thanks for your PR.

I'm waiting for a pingcap member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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[fanrenhoo]

/cc @xiongjiwei

[ti-chi-bot]

@fanrenhoo: GitHub didn't allow me to request PR reviews from the following users: xiongjiwei.

Note that only pingcap members and repo collaborators can review this PR, and authors cannot review their own PRs.

In response to this:

/cc @xiongjiwei

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[fanrenhoo]

/cc @lance6716

[fanrenhoo]

Hi, I found it seems TiDB intendly to trim the spaces at the ending of characters before comparision, including hashjoin with columns, or raw strings. But it does not comply with MySQL. So please review if this fix is correct

[fanrenhoo]

/test

[ti-chi-bot]

@fanrenhoo: Cannot trigger testing until a trusted user reviews the PR and leaves an /ok-to-test message.

In response to this:

/test

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[lance6716]

/ok-to-test

[codecov]

Codecov Report

Attention: Patch coverage is 80.00000% with 1 lines in your changes are missing coverage. Please review.

Project coverage is 73.5822%. Comparing base (3ca57c1) to head (5f541d0).
Report is 4 commits behind head on master.

Additional details and impacted files

@@               Coverage Diff                @@
##             master     #53036        +/-   ##
================================================
+ Coverage   72.0269%   73.5822%   +1.5553%     
================================================
  Files          1499       1499                
  Lines        431250     431883       +633     
================================================
+ Hits         310616     317789      +7173     
+ Misses       101328      94193      -7135     
- Partials      19306      19901       +595     

Flag	Coverage Δ
integration	29.0856% <80.0000%> (?)

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

Components	Coverage Δ
dumpling	53.9957% <ø> (ø)
parser	∅ <ø> (∅)
br	46.3671% <ø> (+8.0212%)	⬆️

[ti-chi-bot]

@fanrenhoo: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
idc-jenkins-ci-tidb/unit-test	5f541d0	link	true	/test unit-test
idc-jenkins-ci-tidb/mysql-test	5f541d0	link	true	/test mysql-test
pull-integration-ddl-test	5f541d0	link	true	/test pull-integration-ddl-test
idc-jenkins-ci-tidb/check_dev	5f541d0	link	true	/test check-dev
idc-jenkins-ci-tidb/check_dev_2	5f541d0	link	true	/test check-dev2

Full PR test history. Your PR dashboard.

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/test-infra repository. I understand the commands that are listed here.

[xiongjiwei]

do not fix like this. create table with collate utf8mb4_unicode_ci in mysql, you will get the same result with tidb

[fanrenhoo]

do not fix like this. create table with collate utf8mb4_unicode_ci in mysql, you will get the same result with tidb

OK，so this issue dont need fix. I will close this issue and pull requet

[fanrenhoo]

close