fix the issue that decimal divide not round.

[LittleFall]

What problem does this PR solve?

Issue Number: close #6393, close #6462, close #4488

Problem Summary: The result of decimal divide won't round at some precision.

What is changed and how it works?

add round logic

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

fix the issue that decimal divides not round in some precision.

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• SeaRise
• bestwoody

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[ti-chi-bot]

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

Commit hash: 04012f1

[LittleFall]

/merge

[ti-chi-bot]

@LittleFall: It seems you want to merge this PR, I will help you trigger all the tests:

/run-all-tests

You only need to trigger /merge once, and if the CI test fails, you just re-trigger the test that failed and the bot will merge the PR for you after the CI passes.

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[ti-chi-bot]

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

Commit hash: 153ea48

[LittleFall]

/merge

[ti-chi-bot]

@LittleFall: It seems you want to merge this PR, I will help you trigger all the tests:

/run-all-tests

You only need to trigger /merge once, and if the CI test fails, you just re-trigger the test that failed and the bot will merge the PR for you after the CI passes.

If you have any questions about the PR merge process, please refer to pr process.

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.

[ti-chi-bot]

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

Commit hash: f1a9064

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-6.1: #6794.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-6.5: #6795.