LESSON 3

Why is data integrity important in database design?

• To optimize query performance

• To ensure accurate and reliable data

• To create database backups

• To define primary keys

What is the purpose of an attribute in a database?

• To define the characteristics of an entity

• To establish a connection between entities

• To represent a group of entities

• To define a relationship between entities

What is a strong entity?

• An entity with multiple attributes

• An entity that is easily identified

• An entity that does not require a relationship with another entity

• An entity with a single value attribute

What is a multivalued attribute?

• Attributes that can't be further divided

• Attributes with multiple values

• Attributes containing only one value

• Attributes that are not physically stored

What is the purpose of cardinality in an ER diagram?

• To show the relationship between entities

• To define the number of instances of one entity that can be associated with the number of instances of another entity

• To list the attributes of an entity

• To represent the dependency among entities

What is the purpose of a crow's foot notation in an ER diagram?

• Representing entity types

• Illustrating cardinality in relationships

• Denoting attribute types

• Highlighting primary keys

Why is it important to map attributes to entities in creating an ERD?

• To understand the relationships between attributes

• To define the structure of the database

• To identify the primary keys

• To ensure data integrity

Which attribute uniquely identifies a student in the database?

• Course_ID

• CourseName

• StudentName

• Student_ID

What is the purpose of entity types in an ERD?

• To define the structure of the database

• To represent real-world objects in the database

• To establish relationships between tables

• To ensure data integrity

What is the purpose of composite attributes in an ERD?

• To represent multiple values for an entity

• To represent attributes that can be further divided into sub-attributes

• To represent attributes that are derived from other attributes

• To represent single values for an entity