Back-End Development Basics of Back End Development 3

Question 1

Which of the following is a characteristic of a NoSQL document database like MongoDB?

Accepted Answer

Stores data as flexible JSON-like documents

Answer

Document databases store records as self-contained JSON-like documents, allowing flexible and nested data structures without a fixed schema.

Question 2

What does horizontal scaling mean for a back-end server?

Accepted Answer

Adding more server instances to distribute load

Answer

Horizontal scaling (scaling out) adds more machines or instances, while vertical scaling (scaling up) increases resources on a single machine.

Question 3

Which protocol is most commonly used for real-time, bidirectional communication between a browser and a server?

Accepted Answer

WebSocket

Answer

WebSocket provides a persistent, full-duplex channel over a single TCP connection, enabling real-time communication without repeated HTTP overhead.

Question 4

What is a race condition in a back-end context?

Accepted Answer

A bug where outcome depends on unpredictable timing of concurrent operations

Answer

A race condition occurs when multiple operations access shared state concurrently and the final result depends on the order of execution, leading to inconsistent behavior.

Question 5

Which of the following best describes an idempotent HTTP method?

Accepted Answer

A method that can be called multiple times without changing the result beyond the first call

Answer

An idempotent method produces the same server state whether it is called once or many times; GET, PUT, and DELETE are idempotent, while POST generally is not.

Back-End Development Practice Test

Back-End Development Practice Test

Back-End Development Basics of Back End Development 3