The objective of all Whitemarsh products is successful enterprise database. Thus, Whitemarsh products address database projects, its staffing, the underlying database technology, DBMS, and repository selection and evaluation.
Supporting this objective is an underlying organization that ensures continuity among all products. The Whitemarsh approach guarantees continuity because all the products are derived from the database taxonomy.
WHITEMARSH DATABASE TAXONOMY
The Whitemarsh enterprise database model is drawn from a single taxonomy that insures continuity and an easy cross reference among topics.
The Whitemarsh enterprise database taxonomy has been under constant refinement since 1973, and is the standard against which all the Whitemarsh products measured. The taxonomy consists of the following four components.
The logical database is the semantics of database objects that are to be represented in the database. A database object contains four parts: data structure, database processes, database object information systems, and database object states. From the enterprise viewpoint, the logical database, through the database objects is the specifications of business policy and the procedures to carry them out. From the technology viewpoint, the logical database is the DBMS language specification of the database objects.
The logical database is prototyped to evolve and validate its final design. Then, during implementation, it is transformed to meet the DBMS's requirements. During the corporate business model maintenance, the logical database is adjusted as necessary.
The physical database is the actualization of the logical database. From the enterprise database model viewpoint, the physical database's specifications, that is, its size, loading and update requirements are determined. From the technology viewpoint, the physical database is database object access mechanisms, indexes, pointers and chains that relate record instances, database object loading and database object update systems, and database object backup procedures. Once specified, these are implemented and adjusted. Subsequent to implementation, these are evolved and maintained as appropriate.
Interrogation is the process of selecting, accessing, and formatting data from database objects for various reports. From the enterprise database model viewpoint, interrogation occurs first as specifications, then as critical or mandatory subsystems, and then finally as the ongoing reports that make database a valuable corporate asset. From the technology viewpoint, database interrogation is realized through a wide selection of computer access languages.
System control is a collection of software, techniques and procedures that support the efforts necessary to protect and secure the database objects, to manipulate the performance characteristics of the DBMS, and to evolve enterprise database to accommodate new requirements. From the enterprise database model viewpoint, system control requirements are initially determined, then fully implemented through subsystems and procedures, and then finally utilized in an on going manner to maintain maximum control over the database system. From the technology viewpoint, system control is either software utilities and/or sequences of technical procedures.
RELEVANCE OF THE TAXONOMY
The Whitemarsh database taxonomy is used to provide a single framework for:
- Developing database projects
- Identifying staffing requirements and manpower loadings
- Understanding the technology surrounding database
- Studying the various database management systems (DBMS)
Each Whitemarsh product is designed with the taxonomy as its basis. Depending upon the goals of the product, some portion of the taxonomy is emphasized more than the others. For example, in the conceptual specification phase of an database project, greater emphasis is placed on the development of the logical database requirements. It also touches on the other portions of the taxonomy as required during the construction of the conceptual specification of the database project.
The database project, reflecting the database taxonomy has a logical database, a physical database, interrogation, and system control.
The project's logical database, when fully developed, becomes a model of the business policy domain to be represented in the database. That business policy domain can be as narrow as an application database, or as broad as a subject area database. In the enterprise database specification phase, the logical database consists of a global statement, in graphic form, and a series of analytic specification, which together, serve to delimit the database's business policy boundaries and to support its integrity.
The specification of the logical database is translated into the specific requirements of the DBMS. At this point, the logical database exists both as a rigorously defined specification, and as a rigorously bound DBMS specification.
The project's physical database when implemented is the actual defined and loaded database. Its major specification component consists of an enumeration of the allowable operations that can occur to the database. Of utmost importance is the subset of update operations. From the DBMS point of view, the physical database is sized, loaded, updated, and saved/restored.
The project's interrogation aspect represents the proper and efficient use
of data. Efficiency is addressed from two angles: minimal consumption of computer resources in program execution, and minimal expenditure of human resources for program development.
The final aspect, the project's system control, is critically important. It addresses the care and control of the database, the DBMS which controls the database, and the application programs that interact against it. Requirements for all the system control components must be specified and rigorously implemented and maintained.