1.R(name,ssn,phone#,city),F={ssn® (name,City)} A.Please calculate all the candidate KEY.B.Is R in 2NF?if R in not in 2NF,Decompose to 2NF.C.Is R in 3NF?if R in not in 3NF,Decompose to 3NF.D.Is R in BCNF?if R in not in BCNF,Decompose to BCNF
Question
1.R(name,ssn,phone#,city),F={ssn® (name,City)} A.Please calculate all the candidate KEY.B.Is R in 2NF?if R in not in 2NF,Decompose to 2NF.C.Is R in 3NF?if R in not in 3NF,Decompose to 3NF.D.Is R in BCNF?if R in not in BCNF,Decompose to BCNF
Solution
A. The candidate key for the relation R is ssn. This is because ssn can uniquely determine all other attributes in the relation.
B. The relation R is not in 2NF because the non-prime attribute 'city' is not fully functionally dependent on the candidate key 'ssn'. We can decompose R into two relations to achieve 2NF: R1(ssn, name) with a functional dependency ssn -> name R2(ssn, city) with a functional dependency ssn -> city
C. After decomposition, the relations R1 and R2 are in 3NF because every non-prime attribute is non-transitively dependent on every candidate key in the relation.
D. The relations R1 and R2 are also in BCNF because for every non-trivial functional dependency X -> Y, X is a superkey. In both R1 and R2, the only non-trivial functional dependency is ssn -> name and ssn -> city, and ssn is a superkey in both relations.
Similar Questions
1.R(name,ssn,phone#,city),F={ssn® (name,City)} A.Please calculate all the candidate KEY.B.Is R in 2NF?if R in not in 2NF,Decompose to 2NF.C.Is R in 3NF?if R in not in 3NF,Decompose to 3NF.D.Is R in BCNF?if R in not in BCNF,Decompose to BCNF
chap8 Homework 10-2024简答题3. Normalize schema :name,ssn,phone#,city1.R(name,ssn,phone#,city),F={ssn® (name,City)} A.Please calculate all the candidate KEY.B.Is R in 2NF?if R in not in 2NF,Decompose to 2NF.C.Is R in 3NF?if R in not in 3NF,Decompose to 3NF.D.Is R in BCNF?if R in not in BCNF,Decompose to BCNF
ssign and print the roll number, phone number and address of two students having names "Sam" and "John" respectively by creating two objects of the class 'Student'.
Imagine you need the information below. Follow the instructions and write the necessary question / response.Ask me about two phone brands. (Use as … as)
hich of the following command is used to get current working directory in R?
Upgrade your grade with Knowee
Get personalized homework help. Review tough concepts in more detail, or go deeper into your topic by exploring other relevant questions.