json: add json_storage_free function

[YangKeao]

Signed-off-by: YangKeao [email protected]

What problem does this PR solve?

Issue Number: close #38517

Problem Summary:

Implement json_storage_free function

What is changed and how it works?

As TiDB doesn't support in place json partial update, json_storage_free function is implemented with simply return an zero for any valid json value.

1. If it's NULL, return NULL
2. If it's an invalid json, return error
3. Else, return 0.

Related tipb updates: pingcap/tipb#274

Check List

Tests

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

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

Add `json_storage_free` function to keep compatible with MySQL

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• xhebox
• xiongjiwei

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[YangKeao]

/run-all-tests

[YangKeao]

Here are some extra changes, because someone forgot to update the bazel rules (through make bazel_prepare). I have checked with @hawkingrei and I could submit these diffs with this PR.

[YangKeao]

/run-unit-test

[YangKeao]

@xiongjiwei @xhebox Could you help me to merge this PR?

[xhebox]

/merge

[ti-chi-bot]

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

Commit hash: e6b896b