IM1 | FINAL EXAMINATION

What is an Entity Relationship Diagram (ERD)?

• A graphical representation of data entities and their attributes.
• A mathematical model used for complex data calculations.
• A method of database encryption.
• A network topology diagram.

Which of the following is NOT a primary component of an ERD?

• Entity
• Relationship
• Attribute
• Loop

In an ERD, what does an entity represent?

• A relationship between two other entities.
• A specific instance of a table in a database.
• A primary key in a database.
• A collection of similar information.

What is the purpose of a relationship in an ERD?

• To define the structure of an attribute.
• To connect entities and show associations between them.
• To create a hierarchy of entities.
• To determine the data types of attributes.

Cardinality in an ERD represents:

• The uniqueness of an entity's identifier.
• The number of attributes an entity can have.
• The maximum number of relationships an entity can have.
• The number of entities in a database.

Which cardinality symbol represents "one and only one" relationship in an ERD?

• 1
• 0..1
• 0..*
• *

In an ERD, a primary key is used to:

• Establish relationships between entities.
• Ensure that entities are unique and identifiable.
• Define attributes for an entity.
• Link two databases together.

What is an attribute in an ERD?

• A relationship between two entities.
• A field that represents a characteristic of an entity.
• A graphical representation of an entity.
• A constraint that enforces data integrity.

In an ERD, a weak entity is an entity that:

• Lacks attributes.
• Does not have a primary key.
• Has a one-to-many relationship.
• Cannot participate in relationships.

What is the purpose of the crow's foot notation in an ERD?

• To represent derived attributes.
• To indicate the cardinality of a relationship.
• To show the primary key of an entity.
• To highlight weak entities.