HCU PHD CS MAY 2015
May 17, 2024Question 3744 – Compiler-Design
May 17, 2024GATE 2008
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Question 82
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Consider the following ER diagram
The minimum number of tables needed to represent M, N, P, R1, R2 is
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3
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4
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5
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Question 82 Explanation:
➝ M, P are entities so they require individual tables.
➝ Here N is a Weak entity, but it need to modify the primary key of P such as P1
M = {M1, M2, M3, P1}
P = {P1, P2}
N = {N1, N2, P1}
➝ Relationship set has its own attribute, then no need to create a separate table.
➝ Finally we require 3 minimum tables to represent M, P, N, R1, R2.
➝ Here N is a Weak entity, but it need to modify the primary key of P such as P1
M = {M1, M2, M3, P1}
P = {P1, P2}
N = {N1, N2, P1}
➝ Relationship set has its own attribute, then no need to create a separate table.
➝ Finally we require 3 minimum tables to represent M, P, N, R1, R2.
Correct Answer: B
Question 82 Explanation:
➝ M, P are entities so they require individual tables.
➝ Here N is a Weak entity, but it need to modify the primary key of P such as P1
M = {M1, M2, M3, P1}
P = {P1, P2}
N = {N1, N2, P1}
➝ Relationship set has its own attribute, then no need to create a separate table.
➝ Finally we require 3 minimum tables to represent M, P, N, R1, R2.
➝ Here N is a Weak entity, but it need to modify the primary key of P such as P1
M = {M1, M2, M3, P1}
P = {P1, P2}
N = {N1, N2, P1}
➝ Relationship set has its own attribute, then no need to create a separate table.
➝ Finally we require 3 minimum tables to represent M, P, N, R1, R2.