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Illustrate the statement 'Projection operation distributes over the union operation'. Give an example.
Ans: ΠL(E1 ∪ E2) = (ΠL(E1)) ∪ (ΠL(E2))
This says that result acquired by projecting on an attribute set A, after taking union of two relations is similar as union of two relations each of which is a projection of original relations on A.
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WHAT IS SQL
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