Modular and Rule-Based Database Programming in DBPL

Abstract

DBPL is the target language for the implementation of data-intensive applications in the DAIDA project. This chapter illustrates how DBPL supports the construction of correct, modular and efficient database programs integrating well-developed compilation and database technology.

After an introduction to the language concepts of DBPL, two methodological aspects central to the implementation of database applications are discussed. The first task is the representation of the classical abstraction principles of Conceptual Modelling (classification, aggregation, generalization, and association) by typed data structures and data derivation rules in DBPL. The second aspect is the decomposition of application systems consisting of multiple interacting programs into managable, shared modules using a novel abstraction mechanism for bulk data access.

By presenting the use of DBPL in some detail, we intend to support our claim that a set- and predicate-oriented view of database modelling resolves the traditional mismatch between declarative database languages and their general-purpose imperative counterparts.

Markus Bittner, Uwe Conradt, Hanno Klein, Michaela Lang, Andreas Rudloff and Norbert Schramek implemented the DBPL database system and its Sparc compiler. Andreas Rudloff also helped in making the DBPL system reliable enough to be distributed and used in education. Finally, we would like to thank Henning Eckhardt for his valuable contribution to the DBPL language design.