An OmniStudio Developer is using a Data Mapper Transform.

A Data Mapper Transform is used to restructure input JSON into the output JSON format required by a target system. Since the target requires a nested array of objects, the developer must map the source value into the correct nested target path so the Data Mapper output structure creates the ContactDetails array and Phone object. A flat direct mapping does not describe the required parent array and child object structure. A Formula is not required just to place an existing source value into a nested output structure; formulas are used when the value itself must be calculated or transformed. Mapping to the root node would lose the required ContactDetails and Phone hierarchy. The correct method is nested target path mapping.

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