Combining Theory and Practice in Integrity Control: A Declarative Approach to the Specification of a Transaction Modification Subsystem

Integrity control is generally considered an important topic in the field of database system research. In the database literature, many proposals for integrity control mechanisms canbe found. A large group of proposals has a formal character, and does not cover complete algorithms that can be used in a real-world database system with multi-update transactions. Another group of proposals is system-oriented and often lacks a complete formalbackground on transactions and integrity control; algorithms are usually described in system terms. This paper combines the essentials of both groups: it presents a declarative specification of a transaction-based integrity control technique that has a solidformal basis and can easily be applied in real-world database systems. The technique, called transaction modification, features simple semantics, full transaction support, and extensibility to parallel data processing. These claims are supported by a prototype implementation of a transaction modification subsystem in the high-performance PRISMA/DB database system. This paper shows that it is well possible for an integrity control technique tocombine a formal approach with complete functionality and high performance.