Back-End Development Basics of Back End Development 5

Question 1

What is the difference between authentication and authorization in a back-end system?

Accepted Answer

Authentication verifies identity; authorization determines what the verified user is allowed to do

Answer

Authentication confirms identity (who you are), while authorization determines permissions (what you are allowed to access or do).

Question 2

Which of the following is a common use case for caching in a back-end application?

Accepted Answer

Keeping frequently read, rarely changed data in memory to reduce database load

Answer

Caching stores the results of expensive operations (e.g., DB queries or API calls) in fast storage like Redis so that repeated requests are served without hitting the database again.

Question 3

What is a foreign key in a relational database?

Accepted Answer

A column that references the primary key of another table to enforce referential integrity

Answer

A foreign key column stores values that match the primary key of a related table, ensuring that relationships between records remain consistent and valid.

Question 4

In a microservices architecture, what is service discovery used for?

Accepted Answer

Allowing services to dynamically find the network location of other services

Answer

Service discovery lets services locate each other dynamically (via a registry like Consul or Kubernetes DNS) rather than relying on hard-coded addresses that change with deployments.

Question 5

What is the purpose of the HTTP OPTIONS method?

Accepted Answer

To retrieve the communication options available for a resource, often used in CORS preflight

Answer

OPTIONS is used by browsers as a preflight request in CORS to ask the server which methods and headers it will accept before sending the actual cross-origin request.

Back-End Development Practice Test

Back-End Development Practice Test

Back-End Development Basics of Back End Development 5