UGC NET CSE | December 2019 | Part 2 | Question: 23

Question

Find minimum number of tables required for converting the following entity relationship diagram into relational database?

• A. $2$
• B. $4$
• C. $3$
• D. $5$

Answer 1

Given ER diagram is 1:M relation.

For $R_2$ we need single table as we can combine $R_2$ with $R_{12}$

$T_1=(R_2,R_{12})$

Entity $R_1$ and attribute $B$ which is a multivalued attribute need a separate table.

$T_2=(R_1)$,

$T_3=(B)$

So total $3$ tables required.

Option $(3)$ is correct.

Answer 2

A will be the answer

First relation will be R12R2 and the other will be R1.

Answer 3

Correct answer will be 4

Considering best deisgn with no null values allowed in the tables

So B is the answer