We can use the following three rules to find logically implied functional dependencies. This collection of rules is calledOptionsAxiomsArmstrong’s axiomsArmstrongClosure
Question
We can use the following three rules to find logically implied functional dependencies. This collection of rules is calledOptionsAxiomsArmstrong’s axiomsArmstrongClosure
Solution
The correct answer is Armstrong’s axioms. These are a set of three inference rules that are used to infer all the functional dependencies on a relational database. They are named after William W. Armstrong, who introduced them in his 1974 paper. The three rules are:
- Reflexivity: If beta is a subset of alpha, then alpha determines beta.
- Augmentation: If alpha determines beta, then gamma & alpha determines gamma & beta.
- Transitivity: If alpha determines beta and beta determines gamma, then alpha determines gamma.
These rules can be applied repeatedly to infer all the functional dependencies in a database.
Similar Questions
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