An input stream in which a data source, a data target, source data fields and target data fields is defined. Any field identifier that is identical to another field identifier is modified to be unique. Once the field identifiers are modified as necessary, the source data fields will be mapped to the target data fields based on the field identifiers. After mapping, the field identifiers will be changed back to their original state, and data associated with the source data fields will be communicated to the data target.