Question: Let R1, R2, Rn be a decomposition of schema U. Let u (U) be a relation, and let r i = IIRI (u). Show that

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

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