Abstract
An attempt is made to enhance the data modelling capabilities of the relational model. Reference pairs and reference graphs of relations are introduced as larger meaningful units than single relations are.
A reference pair models a stylized form of a referential integrity constraint. Together, the reference pairs in a database form a directed graph, which we call a reference graph. Reference graphs add to the relational model a structuring mechanism that is more general than and yet as elegant as related constructs such as complex objects, non first normal form or nested relations.
On these reference graphs an algebra is defined. For single node reference graphs this algebra is reduced to the classical relational algebra. The semantical richness of reference graphs is demonstrated by studying some possible effects on the SQL query language.
Preview
Unable to display preview. Download preview PDF.
References
P.A. Bernstein. "Synthesizing third normal form relations from functional dependencies." In Transactions on Database Systems 1, 4 (Dec. 1976), pp. 277–298.
E.F. Codd. "Extending the relational model to capture more meaning." In Transactions on Database Systems 4, 4 (Dec. 1979), pp. 397–434.
C.J. Date. "Referential integrity." in Proc. Conf. Very Large Databases, Cannes, 9–11 Sept. 1981, pp. 2–11.
R.L. Haskin and R.A. Lorie. "On extending the functions of a relational database system." In Proc. SIGMOD Intl. Conf. on Management of Data, Orlando, June 1982, pp. 207–212.
G. Jaeschke and H.-J. Schek. "Remarks on the algebra of non first normal form relations." In Proc. of ACM SIGACT-SIGMOD Symposium on Principles of Database Systems, Los Angeles, March 1982.
H.F. Korth and J.D. Ullman. "System/U: a database system based on the universal relation assumption." In Proc. XP/1 Conf., 1980.
E.Y. Lien. "Hierarchical schemata for relational databases." In Transactions on Database Systems 6, 1 (March 1981), pp. 48–69.
R. Lorie and W. Plouffe. "Complex objects and their use in design transactions." In Proc. of Annual IEEE Meeting — Database Week, 1983.
D. Maier, J.D. Ullman, M.Y. Vardi. "On the foundations of the universal relation model." In Transactions of Database Systems 9, 2 (June 1984), pp. 283–308.
A. Makinouchi. "A consideration on normal form of not-necessarily-normalized relations in the relational data model." In Proc. Conf. Very Large Databases, Tokyo, 1977, pp. 447–435.
H.-J. Scheck and P. Pistor. "Data structures for an integrated data base management and information retrieval system." In Proc. Conf. Very Large Databases, Mexico City, Sept. 8–10 1982, pp. 197–207.
J.M. Smith and D.C.P. Smith. "Database abstractions: aggregation and generalization." In Transactions on Database Systems 2, 2 (July 1977), 105–133.
J.D. Ullman. Principles of database systems, 2nd edition. Computer Science Press, Rockville, Maryland (1982), 484 p.
Author information
Authors and Affiliations
Editor information
Rights and permissions
Copyright information
© 1988 Springer-Verlag Berlin Heidelberg
About this paper
Cite this paper
Janssens, R. (1988). A theory of reference graphs in relational databases. In: Biskup, J., Demetrovics, J., Paredaens, J., Thalheim, B. (eds) MFDBS 87. MFDBS 1987. Lecture Notes in Computer Science, vol 305. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-19121-6_9
Download citation
DOI: https://doi.org/10.1007/3-540-19121-6_9
Published:
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-540-19121-6
Online ISBN: 978-3-540-39124-1
eBook Packages: Springer Book Archive