Let R1, R2, Rn be a decomposition of schema U. Let u (U) be a relation, and

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Let R1, R2, Rn be a decomposition of schema U. Let u (U) be a relation, and let r i = IIRI (u). Show that u ⊆ r1 1 r2 1 · · · 1 rn

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Database System Concepts

ISBN: 978-0072554816

4th Edition

Authors: Henry F. Korth, S. Sudarshan

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Question Posted: Jan 28, 2011 05:54 AM

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Let R1, R2, Rn be a decomposition of schema U. Let u (U) be a relation, and

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Consider some tuple t in u Note that ri IIRi u implies that tRi ri 1 i n Thus t...View the full answer

Database System Concepts

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