The semantic schema enrichment process used to take an existing relational database schema and map this into a JADE object model makes use of existing JADE object concepts and language constructs, to access the external database in a unified manner.
The schema enrichment process of the External Schema Wizard is not a simple deterministic mapping from a pure relational schema to a JADE object model, as a relational database schema does not generally provide the additional higher level semantic information required for deriving useful relationships between classes.
The transformation of a relational schema into a JADE object model by using the External Schema Wizard is therefore a partially automated process that requires you to specify additional information and for you to have some knowledge of the semantics of the relational database that is being mapped.
In many cases, JADE can derive certain useful information directly from the relational catalog; for example, primary and foreign key specifications. Often, foreign key relationships can also be derived from naming conventions; for example, if dept-id is the primary key of the department table, the External Schema Wizard deduces dept-id in the employee table is probably a foreign key.