expression: separate BuildContext and EvalContext

[lcwangchao]

What problem does this PR solve?

Issue Number: close #52310

Problem Summary:

It's better to separate EvalContext and BuildContext in expression because they all have their respective method in semantics.

For example, if we add a new method EvalContext.Clone in the future to "clone" an EvalContext, BuildContext will also have this method in the current implementation because BuildContext extends EvalContext. It is strange that BuildContext.Clone can be called and an EvalContext returns, so it's better to separate these two methods.

What changed and how does it work?

• BuildContext does not extend EvalContext anymore in this PR.
• BuildContext gives a new method GetEvalContext to return the context for evaluation.

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

[tiprow]

Hi @lcwangchao. Thanks for your PR.

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[YangKeao]

LGTM

[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-04-03 07:39:51.422970903 +0000 UTC m=+429652.950511447: ☑️ agreed by YangKeao.
• 2024-04-03 08:34:59.433768424 +0000 UTC m=+432960.961308970: ☑️ agreed by XuHuaiyu.

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: lance6716, tangenta, XuHuaiyu, YangKeao

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• OWNERS [XuHuaiyu,YangKeao,lance6716,tangenta]
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• pkg/executor/importer/OWNERS [lance6716]
• pkg/expression/OWNERS [XuHuaiyu]
• pkg/lightning/OWNERS [lance6716]
• pkg/table/OWNERS [tangenta]

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