*: add a limitation about not supporting NULLIF() and supporting CASE

[Frank945946]

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What is the related PR or file link(s)?

• This PR is translated from:*: add a limitation about not supporting NULLIF() and supporting CASE #18677
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[ti-chi-bot]

Hi @Frank945946. 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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[lilin90]

/lgtm

[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-09-02 05:51:49.463736381 +0000 UTC m=+250833.981789308: ☑️ agreed by hfxsd.
• 2024-09-02 06:19:33.809794307 +0000 UTC m=+252498.327847232: ☑️ agreed by lilin90.

[hfxsd]

/approve

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: hfxsd

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[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-8.2: #18767.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-8.3: #18768.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-7.1: #18769.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-7.5: #18770.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-8.1: #18771.