Understanding ERD Concepts

What does an Entity represent in an ERD?

• A connection between two relationships

• A real-world object or concept

• An attribute of a primary key

• A unique identifier for a relationship

Which symbol is used to represent an Entity in an ERD?

• Diamond

• Rectangle

• Oval

• Triangle

In an ERD, what is the purpose of a Primary Key?

• To link two entities together

• To uniquely identify each record in an entity

• To describe a relationship between entities

• To represent a many-to-many relationship

What does a Many-to-Many (M) relationship between two entities require in an ERD to be implemented in a relational database?

• A primary key

• A foreign key

• An associative (junction) table

• A composite key

Which of the following is an example of a One-to-Many (1) relationship?

• A student enrolls in multiple courses, and each course has multiple students

• A department has one manager, and a manager can manage multiple departments

• A customer places multiple orders, and each order belongs to one customer

• An employee is assigned to a unique parking space

What symbol represents a relationship in an ERD?

• Oval

• Rectangle

• Diamond

• Line

What is the term used for an attribute or set of attributes in one entity that refers to the primary key of another entity in a relationship?

• Primary Key

• Candidate Key

• Foreign Key

• Composite Key

Which of the following represents a Weak Entity in an ERD?

• A department entity that can exist independently of other entities

• A dependent entity that requires an employee entity for identification

• A course entity that is associated with multiple students

• A product entity that has multiple suppliers

What type of attribute can have multiple values for a single entity?

• Simple Attribute

• Composite Attribute

• Multivalued Attribute

• Derived Attribute

Which relationship type cannot exist directly in a relational database without the use of an intermediate table?

• One-to-One (1:1)

• One-to-Many (1)

• Many-to-One (M:1)

• Many-to-Many (M)