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The $\text{ER}$ diagram shown below depicts a relation between an $\text{EMPLOYEE}$ and its Dependent.

When the above $\text{ER}$ diagram mapped to a relational model, then number of attributes of employee entity and dependent entity which remain non-prime attributes (attributes that are not part of primary key here)?

  1. Employee: $3\: \&$ Dependent: $2$
  2. Employee: $3\: \&$ Dependent: $1$
  3. Employee: $2\: \&$ Dependent: $1$
  4. Employee: $2\: \&$ Dependent: $2$
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First of all we have to check the ER diagram carefully.In this we have :

A) Strong entity employee with eid as the key

B) Weak entity dependent with dob as the partial key

C) A multivalued attribute phoneno..

So we need to have 3 relations :

a) For employee with eid as key

b) For {dependent , has} with {eid,dob} as key with eid being identifier

c) For multivalued attribute phoneno..

So no of attributes which are non prime in employee = 2 [which are dob,ename]

    no of attributes which are non prime in {dependent , has} = 1 [which is dname only]

Hence C) is the correct answer..

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