A normal form for relational databases that is based on domains and keys
ACM Transactions on Database Systems (TODS)
A simplied universal relation assumption and its properties
ACM Transactions on Database Systems (TODS)
On the Equivalence of Database Models
Journal of the ACM (JACM)
On the Desirability of Acyclic Database Schemes
Journal of the ACM (JACM)
Degrees of acyclicity for hypergraphs and relational database schemes
Journal of the ACM (JACM)
A relational model of data for large shared data banks
Communications of the ACM
Principles of Database Systems
Principles of Database Systems
Functional dependencies on cyclic database schemes
SIGMOD '83 Proceedings of the 1983 ACM SIGMOD international conference on Management of data
Answering queries in relational databases
SIGMOD '83 Proceedings of the 1983 ACM SIGMOD international conference on Management of data
GYO reductions, canonical connections, tree and cyclic schemas and tree projections
PODS '83 Proceedings of the 2nd ACM SIGACT-SIGMOD symposium on Principles of database systems
On the recognition of coverings of acyclic database hypergraphs
PODS '83 Proceedings of the 2nd ACM SIGACT-SIGMOD symposium on Principles of database systems
Elimination of intersection amomalies from database schemes
PODS '83 Proceedings of the 2nd ACM SIGACT-SIGMOD symposium on Principles of database systems
The tree property is fundamental for query processing
PODS '82 Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems
Transforming cyclic schemas into trees
PODS '82 Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems
Acyclic Database Schemes (of Various Degrees): A Painless Introduction
CAAP '83 Proceedings of the 8th Colloquium on Trees in Algebra and Programming
Graphs and Hypergraphs
Theory of Relational Databases
Theory of Relational Databases
Alpha-acyclic decompositions of relational database schemes
PODS '86 Proceedings of the fifth ACM SIGACT-SIGMOD symposium on Principles of database systems
On the properties and characterization of connection-trap-free schemes
PODS '86 Proceedings of the fifth ACM SIGACT-SIGMOD symposium on Principles of database systems
Coding theory motivated by relational databases
SDKB'10 Proceedings of the 4th international conference on Semantics in data and knowledge bases
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The acyclicity degree of a relational database scheme is an interesting topic due to several desirable properties of the corresponding database [5,16]. In this paper a simple and homogeneous way to characterize the acyclicity degree of a database scheme is given. The method is based on the existence in all acyclic database schemes of a nonempty set of relation schemes that satisfy a "pruning predicate", which is a property similar to the property satisfied by the leaves in an ordinary tree. This fact implies that such relation schemes may be eliminated using a recursive pruning algorithm in order to determine the acyclicity degree. Furthermore, if we use an incremental step by step design methodology, enriching the scheme one relation at a time, the pruning predicate suggests a set of properties that have to be verified by the new relation scheme in order to preserve the acyclicity degree of the database scheme.