Perfect error-correcting databases
Discrete Applied Mathematics
The characterization of branching dependencies
Discrete Applied Mathematics - Special issue on combinatorial problems in databases
The number of keys in relational and nested relational databases
Discrete Applied Mathematics - Special issue on combinatorial problems in databases
Horn clauses and database dependencies
Journal of the ACM (JACM)
Foundations of Databases: The Logical Level
Foundations of Databases: The Logical Level
Extremal Combinatorial Problems in Relational Data Base
FCT '81 Proceedings of the 1981 International FCT-Conference on Fundamentals of Computation Theory
Counter-free keys and functional dependencies in higher-order datamodels
Fundamenta Informaticae
Keys and Armstrong databases in trees with restructuring
Acta Cybernetica
Minimum matrix representation of closure operations
Discrete Applied Mathematics
Coding theory motivated by relational databases
SDKB'10 Proceedings of the 4th international conference on Semantics in data and knowledge bases
On the existence of armstrong data trees for XML functional dependencies
FoIKS'10 Proceedings of the 6th international conference on Foundations of Information and Knowledge Systems
Note on the size of binary Armstrong codes
Designs, Codes and Cryptography
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The existence of Armstrong-instances of bounded domains is investigated for specific key systems. This leads to the concept of Armstrong(q, k, n)-codes. These are q-ary codes of length n, minimum distance n - k + 1 and have the property that for any possible k - 1 coordinate positions there are two codewords that agree exactly there. We derive upper and lower bounds on the length of the code as function of q and k. The upper bounds use geometric arguments and bounds on spherical codes, the lower bounds are probabilistic.