4.10.1-4.10.3 Fundamentals of databases Quiz

What is the main purpose of a relational database?

• To store data in a non-structured format

• To manage data and maintain relationships between entities

• To create graphical representations of data

• To store data in a hierarchical format

Answer explanation

The main purpose of a relational database is to manage data and maintain relationships between entities, allowing for structured data storage and efficient querying.

In a relational database, what does each table represent?

• A single attribute

• A collection of unrelated data

• An entity

• A primary key

Answer explanation

In a relational database, each table represents an entity, which is a distinct object or concept, such as a customer or product. This allows for organized data storage and relationships between different entities.

Which of the following is an example of a one-to-one relationship in a relational database?

• A teacher and their students

• A student and their courses

• A person and their passport

• A course and its students

Answer explanation

A person and their passport is a one-to-one relationship because each person can have only one passport, and each passport is assigned to only one person. The other options represent many-to-one or one-to-many relationships.

What is a primary key in a relational database?

• An attribute that links to the primary key of another table

• A unique attribute or combination of attributes that uniquely identifies each record within a table

• A column that represents specific properties or characteristics of an entity

• A collection of related data representing an entity

Answer explanation

A primary key is a unique attribute or combination of attributes that uniquely identifies each record within a table, ensuring that no two records have the same key value.

Which type of relationship allows multiple records in one entity's table to be linked to multiple records in another entity's table?

• One-to-One Relationship

• One-to-Many Relationship

• Many-to-Many Relationship

• Many-to-One Relationship

Answer explanation

A Many-to-Many Relationship allows multiple records in one table to be associated with multiple records in another table, making it the correct choice for linking entities in this manner.

What is an attribute in a relational database?

• A unique identifier for each record

• A column in a table representing specific properties or characteristics of an entity

• A collection of related data representing an entity

• A table that links to the primary key of another table

Answer explanation

An attribute in a relational database is a column in a table that represents specific properties or characteristics of an entity, making it essential for defining the data structure.

What is the role of a foreign key in a relational database?

• To uniquely identify each record within a table

• To represent specific properties or characteristics of an entity

• To link to the primary key of another table and establish relationships between entities

• To store data in a non-structured format

Answer explanation

A foreign key links to the primary key of another table, establishing relationships between entities. This is crucial for maintaining referential integrity in a relational database.

Which of the following is an advantage of relational databases related to ensuring data accuracy and consistency?

• Flexibility in Data Retrieval

• Data Integrity

• Scalability

• Security

Answer explanation

Data integrity is a key advantage of relational databases, as they enforce rules and constraints that ensure data accuracy and consistency, preventing errors and maintaining reliable information.

What does SQL (Structured Query Language) allow for in relational databases?

• Ensuring data accuracy

• Complex queries to retrieve, update, and manipulate data

• Managing large datasets

• Controlling access to data

Answer explanation

SQL enables complex queries to efficiently retrieve, update, and manipulate data in relational databases, making it a powerful tool for managing structured data.

Which advantage of relational databases involves organizing data into related tables to reduce redundancy?

• Data Integrity

• Flexibility in Data Retrieval

• Normalisation

• Security

Answer explanation

Normalisation is the process of organizing data into related tables to minimize redundancy and dependency. This ensures data integrity and efficient data management in relational databases.