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What is theta join explain?
Theta Join - The theta join operation is an extension to the natural-join operation which permits us to merge selection and a Cartesian product within a single operation. Consider relations r(R) and s(S), and let θ be a predicate on attributes in the schema R ∪ S. The theta join operation r θ s is described as follows:
r θ s = σθ (r x s)
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 at
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how to solve the C type problems?
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