Homework 6

# Homework 6 - CSC4402 Homework #6 1. Due Wednesday...

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CSC4402 Homework #6 Due Wednesday 11-11-2009 1. Shown belowisa relation value (instance) for the relation r ( R )where the relation schema Ris givenbyR(ABCDE). Relation value for r ( R ) AB CDE A 1 B 1 C 1 D 1 E 1 A 1 B 2 C 1 D 1 E 1 A 2 B 2 C 1 D 2 E 3 A 2 B 3 C 3 D 2 E 2 A 2 B 3 C 3 D 4 E 2 Consider the set of functional dependencies F = {A B, B C, D E, CD E}. Foreach functional dependency(fd) in F ,determine whether or not this fd is satisfied by this relation value for r ( R ). Briefly explain your answer for each fd (whythe fd is satisfied (or not) by this relation value). 2. Let R(ABC) be a relation with attributes A, B and C. Let F 1 and F 2 be sets of functional dependen- cies where F 1 ={ A B, A C}and F 2 ={A B, B C}. (Here to get some intuitions about the relation R, you may think of R as representing information about a person - attribute A represents the SSN of the person, attribute B represents the address of the person, and attribute C represents the phone number of the person. However, this visualization of R should NOTimpact your answers to the question) (a)
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## This note was uploaded on 01/25/2010 for the course CSC 4402 taught by Professor Staff during the Fall '08 term at LSU.

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