Recall DB Design
Week 9: Worksheet
CSC 343 Winter 2021 University of Toronto Mississauga
March 25/26, 2021
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Task I
Consider a relation R with a set of attributes ¦Á = {A, B, C, D, E, F } and the set of Functional Dependencies F = { A ¡ú BC, B ¡ú E, C ¡ú BD, D ¡ú A, E ¡ú F, F ¡ú BE}
(a) Compute the closure of each attribute.
(b) Find all candidate keys (i.e., minimal keys) of relation R.
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Task II
Consider a relation R with a set of attributes ¦Á = {A, B, C, D, E} and the set of Functional Dependencies F = { A ¡ú B, BC ¡ú E, ED ¡ú A}
(a) Is R in 3NF? (b) Is R in BCNF?
HINT 1: Compute the keys first, then solve (a) and (b). HINT 2: Define 3NF and BCNF after HINT 1.
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