Inferences for numerical dependencies
Theoretical Computer Science
Principles of database and knowledge-base systems, Vol. I
Principles of database and knowledge-base systems, Vol. I
On the satisfiability of dependency constraints in entity-relationship schemata
Information Systems
Object-oriented systems analysis: a model-driven approach
Object-oriented systems analysis: a model-driven approach
Reasoning about functional dependencies generalized for semantic data models
ACM Transactions on Database Systems (TODS)
The design of relational databases
The design of relational databases
Making object-oriented schemas more expressive
PODS '94 Proceedings of the thirteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Cardinality constraints in semantic data models
Data & Knowledge Engineering
Dependency preserving refinements and the fundamental problem of database design
Data & Knowledge Engineering - Special issue on ER '96
Complete rules for n-ary relationship cardinality constraints
Data & Knowledge Engineering
The entity-relationship model—toward a unified view of data
ACM Transactions on Database Systems (TODS) - Special issue: papers from the international conference on very large data bases: September 22–24, 1975, Framingham, MA
A relational model of data for large shared data banks
Communications of the ACM
Entity-Relationship Modeling: Foundations of Database Technology
Entity-Relationship Modeling: Foundations of Database Technology
Transforming an Entity-Relationship Schema into Object-Oriented Database Schemas
ADBIS '95 Proceedings of the Second International Workshop on Advances in Databases and Information Systems
Decomposition of Relationships through Pivoting
ER '96 Proceedings of the 15th International Conference on Conceptual Modeling
Improving Quality in Conceptual Modelling by the Use of Schema Transformations
ER '96 Proceedings of the 15th International Conference on Conceptual Modeling
On the Consistency of Int-cardinality Constraints
ER '98 Proceedings of the 17th International Conference on Conceptual Modeling
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In the relational data model, the problem of data redundancy has been successfully tackled via decomposition. In advanced data models, decomposition by pivoting provides a similar concept. Pivoting has been introduced by Biskup et al. [5], and used for decomposing relationship types according to a unary nonkey functional dependency. Our objective is to study pivoting in the presence of cardinality constraints which are commonly used in semantic data models. In order to ensure the equivalence of the given schema and its image under pivoting, the original application-dependent constraints have to be preserved. We discuss this problem for sets of participation and co-occurrence constraints. In particular, we prove the necessity of path cardinality constraints, and give an appropriate foundation for this concept.