The issue was reported some time ago in the community Slack. NULL has to be passed as an actual null symbol (\N) instead of a string 'NULL'. See a similar fix in clickhouse-connect.
Checklist
[x] Unit and integration tests covering the common scenarios were added
[x] A human-readable description of the changes was provided to include in CHANGELOG
Summary
The issue was reported some time ago in the community Slack. NULL has to be passed as an actual null symbol (
\N) instead of a string'NULL'. See a similar fix in clickhouse-connect.Checklist