Suppose R is a relation with attributes A 1 , A 2 ,.An As a function of

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Suppose R is a relation with attributes A ₁, A ₂,……….An

As a function of n, tell how many superkeys R has , if: Theonly keys are (A1, A2}and{A1,A3}

Prove that {X ⁺} ⁺= {X} ⁺

Related Book For answer-question

Database management systems

ISBN: 978-0072465631

3rd edition

Authors: Raghu Ramakrishan, Johannes Gehrke, Scott Selikoff

Posted Date: Apr 02, 2019 10:22 AM

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Suppose R is a relation with attributes A 1 , A 2 ,.An As a function of

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The super keys of the relation R are any subset that contains A 1 A 2 or A 1 A 3 ... View the full answer

Database management systems

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