Persistence layer

The interaction between the business objects and persistence layer is isolated in an object called the Business Object Mediator. Business object document (BOD) commands interact with the Business Object Mediator to handle the interaction with the logical objects and how they are persisted.

The persistence layer maps these structured objects to the persistence implementation to perform the data retrieval or updates. The persistence layer accepts structured data objects (SDOs) which are transformed (mediated) into objects called physical SDOs. Physical SDOs are stored in the data service layer. All persistence-specific assets, such as SQL queries, are isolated within the data service layer. To simplify maintenance, the query template file stores SQL.