Chapter 6, Problem 7PE

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Given a relation schema R = (A, B, C, D, E,G) with a set of functional dependencies F {ABCD BC → DE B→ D D→ A}. (a) Show that R is not in BCNF using the functional dependency A → BCD. (b) Show that AG is a superkey for R (c) Compute a canonical cover Fc for the set of functional dependencies F. Show your work. (d) Give a 3NF decomposition of R based on the canonical cover found in (c). Show your work. (e) Give a BCNF decomposition of R using F. Show your work.

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Chapter 6, Problem 7PE

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Given a relation schema R = (A, B, C, D, E,G) with a set of functional dependencies F {ABCD BC → DE B→ D D→ A}. (a) Show that R is not in BCNF using the functional dependency A → BCD. (b) Show that AG is a superkey for R (c) Compute a canonical cover Fc for the set of functional dependencies F. Show your work. (d) Give a 3NF decomposition of R based on the canonical cover found in (c). Show your work. (e) Give a BCNF decomposition of R using F. Show your work.

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