Relational databases
ACM SIGMOD Record
New methods and fast algorithms for database normalization
ACM Transactions on Database Systems (TODS)
ACM SIGMOD Record
Yet another note on minimal covers
ACM SIGMOD Record
Principles of Database Systems
Principles of Database Systems
Normalizing relational database schemas using mathematica
ICCS'06 Proceedings of the 6th international conference on Computational Science - Volume Part II
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In [1] Nummenmaa and Tanisch show that the algorithm in [2] for computing minimal covers is incorrect even though it purports to correct the algorithms in [3-6]. As they illustrate with F = { A B → C}, the algorithm in [2] allows B to be eliminated as an extraneous attribute since the dependency AB → C is implied by A → C using augmentation. Thus F is replaced by F′ = [A → C], which is clearly not equivalent to F. The problematic step of the algorithm in [2] that allows this to occur is Consider each dependency X → A in some order. If Z is a subset of X such that F is contained in the closure of (F - {X → A}) ∪ {Z → A], then immediately replace X → A by Z → A in F. This step continues until no left side of any dependency in F can be reduced