PC++ uses the technique of data manipulation language (DML) binding to provide type-orthogonal persistency . The PC++ programmer can choose the classes and the instances that s/he wants to make persistent. S/he uses a new key word, namely dbclass, to declare persistent classes. PC++ accomplishes the translation from the object to the relational model by extending persistent classes with a new data member, OID, and with new methods to handle the communication with the RDBMS through ODBC, like for example a new method Store() to enable the storage of class instances. Every class is extended to provide persistency also for the instances of classes related to a persistent class, for instance through a part-of or inheritance relation.