Abstract: A relational mapper supports the storage of objects from an object oriented environment in one or more relational databases. The relational mapper generates tables in a relational data store for abstract class types, and it generates a mapping, in any predetermined relationship, to map at least one member of an object to a table for the class type in the relational data store. The relational mapper maps members of a class type to members of a data source. A storage type map is generated to map the data source members of the data source to columns of the relational database table for the class type. The relational mapper is bidirectional such that the relational mapper maps data from a relational database to create objects in accordance with a type system of an object oriented environment. The relational mapper generates metadata to describe the object such that the object, created from the relational database, is a full fledged object of the object oriented system.