JSON null not support as a value for VARIANT column

[waichee]

Description

We have tried to insert JSON null value for a VARIANT column type but only able to create SQL null. There is a test for this in this codebase but the resultant column value created does not match the expectation.

Library version used

net.snowflake:snowflake-ingest-sdk:2.3.0

Steps to reproduce

Steps to reproduce using snowpipe streaming SDK

Example 1: setting null to the variant field named col1 in the Map sent to the sdk
JSON object inserted in app via snowpipe streaming SDK
Map entry: "col1",
Map value: null

Resultant Snowflake table
col1 returns SQL null

Expected results : col1 should return JSON null

Example 2: setting the col column to string "null"
JSON object inserted in app via snowpipe streaming SDK
Map entry: "col1",
Map value: "null"

Resultant Snowflake table (null string not JSON null)
col1 : "null"

[sfc-gh-rcheng]

Thanks for raising this issue. We are currently investigating the issue, you're right in that the test doesn't seem to cover this use case correctly.

you could use is_null_value(xxx) is null, however it doesn't quite resolve the original issue