© 1986 by British Computer Society
EFDM: Extended Functional Data Model

1 Digital Equipment Corporation, 301 Rockrimmon Boulevard, Colorado Springs, Colorado 80919, USA, 2 Department of Computing Sciences, University of Glasgow, Glasgow, UK
This paper reports on an implementation of the functional data model and the associated data language. The notable features of the data model underlying the implementation include its object orientation, use of the extended function concept to model both attributes and relationships, hierarchically organised entity types with property inheritance, and the specification of derived functions which are used to infer automatically the data implied from that held explicitly in the database. The implementation provides an interactive user interface that supports a high-level set-based query and update language. Facilities for defining and using named views are provided. Meta data is made part of the database so that it can be examined using the data language. The implementation is done using the persistent algorithmic language PS-Algol.
Received February 1984.
* To whom correspondence should be addressed. Current address: Digital Equipment Corporation, 301 Rockrimmon Boulevard, Colorado Springs, Colorado 80919, U.S.A.
Current address: Department of Computing Sciences, University of Glasgow, Glasgow, U.K.
¶ Department of Computer Science, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JZ