1. A computer-implemented method for persisting an object in a relational database at an application program run-time, the method comprising the steps of: determining fields of said object; creating in a relational database a row corresponding to said object and one or more columns corresponding to said fields; creating a schema map object, said schema-map object defining a mapping between said fields of said object and said columns; unencapsulating said object to read values of said fields; and storing said values of said fields in said columns to which said fields are mapped in accordance with said schema map object.