Explain projection operation distribute over union operation, Database Management System

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Illustrate the statement 'Projection operation distributes over the union operation'. Give an example.

Ans: Π_L(E₁ ∪ E₂) = (Π_L(E₁)) ∪ (Π_L(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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