planner: use ordered index with is null predicate

[HaoW30]

What problem does this PR solve?

Issue Number: close #54188

Problem Summary:
Properly classify columns with null predicates (e.g. WHERE a IS NULL) as constant so index selection can take advantage of that to satisfy a sort in
as constant so index selection can take advantage of that to satisfy a sort in:

tidb/pkg/planner/core/find_best_task.go

Dupe of #54253 and #54290 with CI failure fixes. @ari-e is out for a bit so attempting to unblock this while he is out.

What changed and how does it work?

Added checks for is null predicate during planning and fill corresponding data structures marking that column as a constant.

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

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

Documentation

• 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.

None

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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1 out of 2 committers have signed the CLA.

✅ ari-e
❌ Hao Wang

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[ti-chi-bot]

Hi @HaoW30. 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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[hawkingrei]

/ok-to-test

[tiprow]

@HaoW30: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
fast_test_tiprow	c6b4520	link	true	/test fast_test_tiprow

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[ti-chi-bot]

@HaoW30: 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/mysql-test	c6b4520	link	true	/test mysql-test
idc-jenkins-ci-tidb/check_dev	c6b4520	link	true	/test check-dev
idc-jenkins-ci-tidb/unit-test	c6b4520	link	true	/test unit-test
idc-jenkins-ci-tidb/check_dev_2	c6b4520	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.

[codecov]

Codecov Report

Attention: Patch coverage is 88.00000% with 3 lines in your changes missing coverage. Please review.

Project coverage is 55.6750%. Comparing base (ef0a3eb) to head (c6b4520).
Report is 10 commits behind head on master.

Additional details and impacted files

@@                Coverage Diff                @@
##             master     #54512         +/-   ##
=================================================
- Coverage   72.8750%   55.6750%   -17.2000%     
=================================================
  Files          1544       1665        +121     
  Lines        436218     608332     +172114     
=================================================
+ Hits         317894     338689      +20795     
- Misses        98779     246403     +147624     
- Partials      19545      23240       +3695     

Flag	Coverage Δ
integration	23.0392% <88.0000%> (?)

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

Components	Coverage Δ
dumpling	52.9656% <ø> (ø)
parser	∅ <ø> (∅)
br	52.6041% <ø> (+6.7332%)	⬆️

[HaoW30]

Closing this PR as we switching back to Ari's original PR ticket