spark
represents a pre-registered Featureform object. In the df_transform API, explicit input setting is necessary. The decorated function should return a dataframe. Conversely, the SQL API embeds inputs using the {{name.variant}}
or {{name}}
syntax, depending on variant availability. The function should return a SQL-like string. This versatility enables you to harness the full potential of both SQL and dataframe transformations, tailored to your specific requirements, preferences, and infrastructure.