Control Programs and Data Structures for a Multiple Alerter Implementation in a Relational Data Base.
Abstract
This paper describes the control programs and data structures used to implement multiple alerters in a relational data model environment. Alerters provide data base management systems with the capabilities of dynamically monitoring for the presence of user defined states of the data, and executing some predetermined action as a consequence of their detection. One of the main considerations in the implementation of an alerter system on a relational data base is the efficiency with which a change to a virtual relation can be detected. Programs are described for the definition, maintenance and evaluation of virtual relations. This work includes details of the use of construction diagrams as a means for their representation, as well as descriptions of the techniques for avoiding unnecessary recomputation and, when required, efficiently performing partial evaluation. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1978
- Accession Number
- ADA067168
Entities
People
- Carlos J. Serra