Let R be a relation schema with a set F of FDs. Prove that the decomposition of

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Let R be a relation schema with a set F of FDs. Prove that the decomposition of R into R1 and R2 is lossless-join if and only if F+ contains R1 ∩ R2 → R1 or R1 ∩ R2 → R2.

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Database management systems

ISBN: 978-0072465631

3rd edition

Authors: Raghu Ramakrishan, Johannes Gehrke, Scott Selikoff

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Question Posted: Jun 27, 2016 06:07 AM

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Let R be a relation schema with a set F of FDs. Prove that the decomposition of

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For both directions if and onlyif we use the notation C R 1 R 2 X R 1 C Y R 2 C so thatR 1 XC R 2 CY ...View the full answer

Database management systems

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