Computational problems related to the design of normal form relational schemas
ACM Transactions on Database Systems (TODS)
Subset Dependencies and a Completeness Result for a Subclass of Embedded Multivalued Dependencies
Journal of the ACM (JACM)
Properties of functional-dependency families
Journal of the ACM (JACM)
A complete axiomatization for functional and multivalued dependencies in database relations
SIGMOD '77 Proceedings of the 1977 ACM SIGMOD international conference on Management of data
Principles of Database Systems
Principles of Database Systems
Data Models
Computers and Intractability: A Guide to the Theory of NP-Completeness
Computers and Intractability: A Guide to the Theory of NP-Completeness
Inferences involving embedded multivalued dependencies and transitive dependencies
SIGMOD '80 Proceedings of the 1980 ACM SIGMOD international conference on Management of data
Applying approximate order dependency to reduce indexing space
SIGMOD '82 Proceedings of the 1982 ACM SIGMOD international conference on Management of data
Inclusion dependencies and their interaction with functional dependencies
PODS '82 Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems
Interactive support for non-programmers: The relational and network approaches
SIGFIDET '74 Proceedings of the 1974 ACM SIGFIDET (now SIGMOD) workshop on Data description, access and control: Data models: Data-structure-set versus relational
The relational and network approaches: Comparison of the application programming interfaces
SIGFIDET '74 Proceedings of the 1974 ACM SIGFIDET (now SIGMOD) workshop on Data description, access and control: Data models: Data-structure-set versus relational
Proceedings of the VLDB Endowment
Differential dependencies: Reasoning and discovery
ACM Transactions on Database Systems (TODS)
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The notion of "sort set" is introduced here to formalize the fact that certain database relations can be sorted so that two or more columns are simultaneously listed in order. This notion is shown to be applicable in several ways to enhance the efficiency of an implemented database. A characterization of when order dependency implies the existence of sort sets in a database is presented, along with several corollaries concerning conplexlty, Armstrong relations and cliques of certain graphs.Sort-set dependencies are then introduced A (finite) sound and complete set of inference rules for sort-set deoendencies is presented, but there is no such set for functional and sort-set dependencies taken together. Deciding logical immplication for sort-set dependencies is proved to be polynomial, but if functional dependencies are included the problem is co-NP complete. Each set of sort-set and functional dependencies is shown to have an Armstrong relation A natural generalization of Armstrong relation, here called "separator," is given and then used to study the relationship between order and sort-set dependencies.