Data Access and Abstraction Layer

Data access is performed through Hibernate O/R mapping and query service. Hibernate as mentioned before is a service that hosts all the entity business objects mappings, provides data access through the mapping of table rows to objects, object persistence, caching facilities, RDBMS independent SQL statements etc.

Accessing the service of Hibernate is done through utility classes that provide the abstraction to allow the use of a different O/R mapping service with no need of changing the Business components. Hibernate is the O/R mapping service of choice but this can be changed. There are multiple O/R mapping services for Java such as TopLink, CocoBase, Torque, ObjectRelationalBridge, Castor.

CRM.COM Software in some cases executes directly SQL statements residing in some XML files called datasets. Datasets are defined using a CRM.COM tool called Dataset Designer. Using the dataset designer the developer can define very easily and quickly datasets, lookups and database tree definitions. Utilities are available within the dataset designer to enable the developer to test the resulting SQL statements in all database environments (e.g. Oracle and MS SQL Server). Once the dataset definitions have been developed and tested, they can be used by the application. Datasets are used on the View layer mostly for data searches.