This archive contains a collection of reports generated by the faculty and students of the Institute for Systems Research (ISR), a permanent, interdisciplinary research unit in the A. James Clark School of Engineering at the University of Maryland. ISR-based projects are conducted through partnerships with industry and government, bringing together faculty and students from multiple academic departments and colleges across the university.
Browsing Institute for Systems Research Technical Reports by Subject "active rule bases"
(1991) Mark, Leo; Roussopoulos, N.; Cochrane, Roberta J.; ISR
Relational database systems suffer from the lack of a rich update language. In this paper we present the Update Dependency Language which allows the database designer to specify a procedure for each update that is activated when attempts are made to perform the update. Each procedure integrates the update dependencies for an update and provides an operational semantics for the update which is maintained by the system. We provide a formal definition for this language, illustrate its use, and discuss concurrency control issues related to integrating such a language into a database system.