executor: fix ifnull bug when arg is enum/set (#25110)

[ti-srebot]

cherry-pick #25110 to release-4.0
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---

Signed-off-by: guo-shaoge [email protected]

What problem does this PR solve?

Issue Number: close #24944

Problem Summary: Just as this comment said. ifnull will be removed if its first argument has not null attributes. But it doesn't work properly if first argument is enum/set. Because enum/set has two semantics(int/string). We may use its string semantics unexpectedly. So we cannot remote ifnull if its first argument is enum/set.

What is changed and how it works?

What's Changed: If ifnull's first argument is enum/set, doesn't rewrite it.

Related changes

• Need to cherry-pick to the release branch

Check List

Tests

• Integration test

Side effects: We may lose some performance for ifnull expression when argument is enum/set. But we have to do it to make it right.

Release note

• executor: fix ifnull bug when arg is enum/set

[ti-srebot]

/run-all-tests

[ti-srebot]

@guo-shaoge you're already a collaborator in bot's repo.

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[XuHuaiyu]

LGTM

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• XuHuaiyu
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[zhouqiang-cl]

/merge

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

Commit hash: f9ccc5e

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