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Given a set of dependencies F on R, the projection of F on Ri, denoted by
'lTR(F) where Ri is a subset of R, is the set of dependencies X ---.. Y in P+ such that the
attributes in X U Yare all contained in Ri• Hence, the projection of F on each relation
schema Ri in the decomposition D is the set of functional dependencies in P+, the closure
of F, such that all their left- and right-hand-side attributes are in Ri• We say that a
decomposition D '= {R[, Rz, ... , Rm} of R is dependency-preserving with respect to F if
the union of the projections of F on each Ri in D is equivalent to F; that is,
(('lTR (F» U ... U ('lTR (F)W '= P+
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∙ 11y ago
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A region that belongs to another state?
Dependency
What is trivial dependency?
A DEPENDENCY X->Y IS SAID TO BE TRIVIAL DEPENDENCY IF Y IS A PROPER SUBSET OF X OTHERWISE NON TRIVIAL DEPENDENCY.
What is post-natal dependency?
Dependency after birth.
What is non trivial dependency?
A DEPENDENCY X->Y IS SAID TO BE TRIVIAL DEPENDENCY IF Y IS A PROPER SUBSET OF X OTHERWISE NON TRIVIAL DEPENDENCY.
When was Ross Dependency created?
Ross Dependency was created in 160.
What is Ross Dependency's population?
The population of Ross Dependency is 1,000.
What is the population of Ross Dependency?
Ross Dependency's population is 200.
What is Ross Dependency's motto?
Ross Dependency's motto is 'Not applicable'.
Easter Island is a dependency of what contry?
Easter Island is a dependency of Chile.
How do you spell depedndancy?
Dependency. You were close haha :)
What is non trivial functional dependency?
-->non trivial functional dependency is totally opposite to the trivial functional dependency. --> non trivial dependency means X-->Y that is if Y is not proper subset of X table or relation with X then it said to be non trivial functional dependency.
What is non dependence?
A DEPENDENCY X->Y IS SAID TO BE TRIVIAL DEPENDENCY IF Y IS A PROPER SUBSET OF X OTHERWISE NON TRIVIAL DEPENDENCY.
