Active Database Management Systems (ADBMSs) have been developed to support applications with detecting changes in databases. This includes support for specifying active rules that monitor changes to data and rules that perform some control tasks for the applications. Active rules can also be used for specifying constraints that must be met to maintain the integrity of the data, for maintaining long-running transactions, and for authorization control.

This thesis begins with presenting case studies on using ADBMSs for monitoring and control. The areas of Computer Integrated Manufacturing (CIM) and Telecommunication Networks have been studied as possible applications that can use active database technology. These case studies have served as requirements on the functionality that has later been developed in an ADBMS. After an introduction to the area of active database systems it is exemplified how active rules can be used by the applications studied. Several requirements are identified such as the need for efficient execution of rules with complex conditions and support for accessing and monitoring external data in a transparent manner.

The main body of work presented is a theory for incremental evaluation, named partial differencing. It is shown how the theory is used for implementing efficient rule condition monitoring in the AMOS ADBMS. The condition monitoring is based on a functional model where changes to rule conditions are defined as changes to functions. External data is introduced as foreign functions to provide transparency between access and monitoring of changes to local data and external data. The thesis includes several publications from both international journals and international conferences.The papers and the thesis deal with issues such as a system architecture for a CIM system using active database technology, extending a query language with active rules, using active rules in the studied applications, grouping rules into modules (rule contexts), efficient implementation of active rules by using incremental evaluation techniques, introducing foreign data into databases, and temporal support in active database systems for storing events monitored by active rules. The papers are complemented with background information and work done after the papers were published, both by the author and by colleagues.