ER Model and Normalization Practice Questions for GATE CSE

Question 1: Rent Payment Management in Hotel System

Consider the entities ‘Apartment’ and ‘Tenant’ with a many-to-many relationship ‘Lease’ as shown below:

If we wish to store information about the monthly rent paid by tenants occupying different apartments, this information should appear as an attribute of:

1. Tenant
2. Apartment
3. Lease
4. None of these

Question 2: Relational Schema in Normalization

Consider an Entity-Relationship Diagram (ERD), where two entities Branch and Department have a relationship Association of cardinality 1:m.

• Attributes of Branch: BID (key), BName, BCity
• Attributes of Department: DID (key), DName, DHead (multi-valued)

How many tables are required to satisfy 3NF in the database?

1. 2
2. 3
3. 4
4. 5

Question 3: Weak and Owner Entity Participation

In the context of Owner and Weak Entity Sets in the Entity-Relationship (ER) model, which one of the following statements is TRUE?

1. The weak entity set MUST have total participation in the identifying relationship.
2. The owner entity set MUST have total participation in the identifying relationship.
3. Both weak and owner entity sets MUST have total participation in the identifying relationship.
4. Neither weak entity set nor owner entity set MUST have total participation in the identifying relationship.

Question 4: Representation of Supporting Relationships

Which one of the following is used to represent the supporting many-one relationships of a weak entity set in an Entity-Relationship diagram?

1. Diamonds with double/bold borders
2. Rectangles with double/bold borders
3. Ovals with double/bold borders
4. Ovals that contain underlined identifiers

Question 5: Many-to-One Relationship in ER Model

In an Entity-Relationship (ER) model, suppose Association is a many-to-one relationship from entity set Teacher to entity set Course. Assume that Teacher and Course participate totally in the relationship, and that the cardinality of Teacher is greater than the cardinality of Course.

Which one of the following is TRUE about the relationship?

1. Every entity in Teacher is associated with exactly one entity in Course.
2. Some entities in Teacher are associated with more than one entity in Course.
3. Every entity in Course is associated with exactly one entity in Teacher.
4. Every entity in Course is associated with at most one entity in Teacher.

Question 6: Conditions for Relational Table Merging

Consider an ER model of a database consisting of entity types X and Y, connected by a relationship Association which does not have its own attributes. Under which one of the following conditions can the relational table for Association be merged with that of X?

1. Association is one-to-many and the participation of X is total.
2. Association is one-to-many and the participation of X is partial.
3. Association is many-to-one and the participation of X is total.
4. Association is many-to-one and the participation of X is partial.