executor: fix the wrong output when the whole data of partition table…

[winoros]

What problem does this PR solve?

Issue Number: close #41801

Problem Summary:

What is changed and how it works?

In the master branch, we support the merge operation for Reader executor.
In this release branch, we provide a quick fix on the order prop push down for partitioned table miss the corner case for index scan.

Check List

Tests

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

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.

Fix the bug that TiDB might return wrong results when the partition table is tiny and is put into only one region.

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• Defined2014
• time-and-fate

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[hawkingrei]

/retest

[hawkingrei]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: 998c5f1

[hawkingrei]

/retest

[chrysan]

/retest

[hawkingrei]

/retest

[Defined2014]

It's not a unstable test :(
PTAL about TestIndexJoinUnionScan @winoros

[Defined2014]

/hold

[winoros]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: 7177845

[winoros]

/unhold

[winoros]

/merge

[ti-chi-bot]

@winoros: 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
idc-jenkins-ci-tidb/unit-test	4f48c81	link	true	/test unit-test

Full PR test history. Your PR dashboard.

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