When you read data from a relational source and write JSON data to a Kafka target, you must use a Hierarchy Builder transformation.

The transformation processes relational input from the upstream transformation and provides JSON output to the downstream transformation. The Hierarchy Builder transformation produces JSON output based on the sample schema of the target table that you associate with the transformation and the way that you map the data.

For more information on using the Hierarchy Builder transformation with Kafka Connector, see https://docs.informatica.com/integration-cloud/cloud-data-integration-connectors/h2l/1544-converting-relational-input-into-hierarchical-output-using-.html.