Expressive, yet tractable XML keys
Proceedings of the 12th International Conference on Extending Database Technology: Advances in Database Technology
On Inferences ofWeak Multivalued Dependencies
Fundamenta Informaticae
Spoilt for Choice: Full First-Order Hierarchical Decompositions
WoLLIC '09 Proceedings of the 16th International Workshop on Logic, Language, Information and Computation
Constraint acquisition for Entity-Relationship models
Data & Knowledge Engineering
On the role of the complementation rule for data dependencies over incomplete relations
WoLLIC'10 Proceedings of the 17th international conference on Logic, language, information and computation
Characterisations of multivalued dependency implication over undetermined universes
Journal of Computer and System Sciences
ACM Transactions on Database Systems (TODS)
Appropriate inferences of data dependencies in relational databases
Annals of Mathematics and Artificial Intelligence
On Inferences of Full First-Order Hierarchical Decompositions
Fundamenta Informaticae - Logic, Language, Information and Computation
On Inferences ofWeak Multivalued Dependencies
Fundamenta Informaticae
Probabilistic conditional independence under schema certainty and uncertainty
SUM'12 Proceedings of the 6th international conference on Scalable Uncertainty Management
Reasoning about functional and full hierarchical dependencies over partial relations
Information Sciences: an International Journal
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The implication of multivalued dependencies in relational databases has originally been defined in the context of some fixed finite universe. While axiomatisability and implication problems have been intensely studied with respect to this notion almost no research has been devoted towards the alternative notion of implication in which the underlying universe of attributes is left undetermined. Based on a set of common inference rules we establish all axiomatisations in undetermined universes, and all axiomatisations in fixed universes that indicate the role of the complementation rule as a means of database normalisation. This characterises the expressiveness of several incomplete sets of inference rules. We also establish relationships between axiomatisations in fixed and undetermined universes, and study the time complexity of the implication problem in undetermined universes. The results of this paper establish a foundation for reasoning about multivalued dependencies without the assumption of a fixed underlying universe.