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Define functional and multivalued dependencies.
Ans: A functional dependency is a assets of the semantics of the attributes in a relation. The semantics point out how attributes relate to one another, and identify the functional dependencies between attributes. While a functional dependency is available, the dependency is fixed as a constraint among the attributes. Refer a relation with attributes A and B, in which attribute B is functionally dependent on attribute A. If we know the value of A and we inspect the relation that holds this dependency, we will find out just only one value of B in all of the tuples which have a given value of A, at any moment in time. Note though, that for a given value of B there may be various different values of A.
Multivalued Dependencies: A multivalued dependency is an outcome of two independent 1: N relationships A: B and A: C being mixed in similar relation R(A,B,C)
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A relation instance indicates as r is a collection of tuples for a given relational schema at a exact point of time. A relation state r of the relation schema R (A 1 ,A 2 ,.....
Why older data models are being replaced by new data modelling 100 words accepted#
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Question: (a) One of the steps in the five-step problem-solving model is implementation. Implementation is considered a key step in the problem-solving model. A problem may be
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