Which tool is used to define relationships between fields in an import set table and a target table?

A Schema Map visually represents the database schema and table relationships, but it is not used to define field-level data transformations for imports.

"Field Transformer" is not a standard ServiceNow component or tool used for defining field relationships in the context of data imports.

A Transform Map is a set of field maps that determine the relationships between fields in an import set table and fields in an existing ServiceNow table. It specifies how data from the staging (import set) table should be transformed and mapped to the target table during an import process.

"Transform Schema" is not a standard ServiceNow component or tool used for defining field relationships in the context of data imports; the correct term is Transform Map.