8.28 Show that the following decomposition of the schema r (A, B, C, D, E) is not a lossless-join decomposition: (A,B,C) (C,D, E). Hint: Give an example of a relation r on schema R such that IIA.B.C(r) X IIc.D.E(r) ≠r
Added by Debra C.
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We have the schema r (A, B, C, D, E) and the decomposition (A,B,C) (C,D,E). Show more…
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Key Concepts
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