PNG60403 TOPIC 3.4

What is the purpose of an Entity-Relationship Diagram (ERD) in database design?

• To create backup copies of the database

• To design user interfaces for the database

• To execute SQL queries directly

• To represent the entities and relationships in a database visually

How are entities typically represented in an ERD?

• Squares

• Circles

• Triangles

• Rectangles

What is a primary key in an ERD?

• A way to link entities to each other

• An attribute that is not important

• A secondary identifier for each entity instance

• A unique identifier for each entity instance

How are attributes represented in an ERD?

• Ovals connected to entity rectangles

• Squares connected to entity rectangles

• Triangles connected to entity rectangles

• Circles connected to entity rectangles

What do relationships describe in an ERD?

• The page layout of the diagram

• The font size of the text

• How entities interact with each other

• The color scheme of the diagram

What does cardinality specify in an ERD?

• The number of instances of one entity that can be associated with instances of another entity

• The color of the entities

• The shape of the attributes

• The size of the relationships

What is a foreign key in an ERD?

• A key used for encryption purposes

• A key that opens a secret door in the database

• An attribute in one entity that links to the primary key of another entity

• A key that is not important

What is the purpose of the University Database ERD example?

• To demonstrate the entities and relationships in a university database

• To showcase the use of colors in ERDs

• To create a fictional story about a university

• To design a new database system

What is the main function of the Products table in the manufacturing ERD?

• Stores details of customer orders

• Stores details of customers

• Stores details of suppliers

• Stores details of each product manufactured

What does the Supplies relationship describe in the manufacturing ERD?

• The relationship between Products and Production processes

• The relationship between Orders and Products

• The relationship between Customers and Orders

• The relationship between Suppliers and Products