Translation of entity-relationship diagrams into relational structures

Abstract An entity-relationship diagram (ERD) is considered to have two conceptual domains: its upper and lower conceptual domains. The semantic properties intrinsic in the upper conceptual domain were studied recently by Lien. In this paper, we discuss the properties inherent in the lower conceptual domain. We show that the latter contains a significant portion of the semantic information of an ERD and helps determine its data representation power. We develop the notions of fundamental functional dependencies (FDs) which can be readily recognized for the lower conceptual domain of an ERD, and regular ERDs which are ERDs such that all the FDs present among their attributes can be derived from their fundamental FDs. Then we give conditions under which a large number of ERDs are equivalent to their underlying relational structures.

[1]  Y. Edmund Lien,et al.  On the Equivalence of Database Models , 1982, JACM.

[2]  Catriel Beeri,et al.  A complete axiomatization for functional and multivalued dependencies in database relations , 1977, SIGMOD '77.

[3]  Ronald Fagin,et al.  A simplied universal relation assumption and its properties , 1982, TODS.

[4]  C. Robert Carlson,et al.  A generalized access path model and its application to a relational data base system , 1976, SIGMOD '76.

[5]  David Maier,et al.  Maximal objects and the semantics of universal relation databases , 1983, TODS.

[6]  Jeffrey D. Ullman,et al.  Principles of Database Systems , 1980 .

[7]  Sushil Jajodia,et al.  The Problem of Equivalence for Entity-Relationship Diagrams , 1983, IEEE Transactions on Software Engineering.

[8]  Edward Sciore,et al.  Some Observations on Real-World Data Dependencies , 1980, XP1 Workshop on Database Theory.

[9]  Catriel Beeri,et al.  On the Desirability of Acyclic Database Schemes , 1983, JACM.

[10]  Edward Sciore.  Real-world MVD's , 1981, SIGMOD '81.

[11]  Y. Edmund Lien.  Multivalued Dependencies With Null Values In Relational Data Bases , 1979, Fifth International Conference on Very Large Data Bases, 1979..

[12]  Sushil Jajodia,et al.  On the Representation of Relational Structures by Entity-Relationship Diagrams , 1983, ER.

[13]  Catriel Beeri,et al.  Elimination of intersection anomalies from database schemes , 1986, JACM.

[14]  Ronald Fagin,et al.  Degrees of acyclicity for hypergraphs and relational database schemes , 1983, JACM.

[15]  Catriel Beeri,et al.  Elimination of intersection amomalies from database schemes , 1983, PODS '83.

[16]  Carlo Zaniolo.  Database relations with null values , 1982, PODS '82.

[17]  ChenPeter Pin-Shan.  The entity-relationship modeltoward a unified view of data , 1976 .