Sometimes the primary key of a table does not only keep a counter for the uniqueness of the row but also additional information like the name of a person. This name is copied in all tables that have foreign key references to the person table. With OpenAccess ORM it is possible to map this foreign key reference to a reference field in the class model. This is fine if you need the complete information of the referenced person, but if you need only the name you do not want to build up the referenced person object in memory and you do not want to make an sql join statement to fetch the information.
OpenAccess ORM has the possibility to map the content of a column to more then one field. In this case you can use this to map the referenced person’s name to a string field in the referencing object (refer to Mapping Value References for information about how the mapping is set up).