Given a set of functional dependencies, the Armstrong relation is a relation which satisfies all the functional dependencies in the closure and only those dependencies. Unfortunately, the minimum-size Armstrong relation for a given set of dependencies can have a size which is an exponential function of the number of attributes in the dependencies considered.
Read more about this topic: Armstrong's Axioms
Famous quotes containing the words armstrong and/or relation:
“There dwelt a man in faire Westmerland,
Jonnë Armestrong men did him call,
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—Unknown. Johnie Armstrong (l. 1–4)
“Our sympathy is cold to the relation of distant misery.”
—Edward Gibbon (1737–1794)