Full-Stack Development Technology & Digital Applications 5

Question 1

What is the main benefit of using WebSockets over HTTP polling for real-time features?

Accepted Answer

WebSockets provide a persistent, full-duplex channel eliminating repeated request overhead

Answer

After the handshake, a WebSocket connection stays open, allowing both client and server to send messages instantly without the overhead of repeated HTTP requests.

Question 2

In semantic versioning (SemVer), when should the major version number be incremented?

Accepted Answer

When making backwards-incompatible (breaking) API changes

Answer

SemVer's major version signals breaking changes that require consumers to update their code to remain compatible.

Question 3

Which approach best describes server-side rendering (SSR) in a Next.js application?

Accepted Answer

HTML is generated on the server per request and sent to the client, improving initial load and SEO

Answer

With SSR, Next.js generates the full HTML on the server for each request, giving search engines crawlable content and users a faster first paint.

Question 4

What is the purpose of database indexing, and what is its main trade-off?

Accepted Answer

Indexing speeds up read queries on indexed columns; trade-off is additional storage and slower writes

Answer

An index creates an auxiliary data structure that allows the database to locate rows faster, but it must be updated on every write, adding overhead.

Question 5

In OAuth 2.0, what does the authorization code flow provide that the implicit flow does not?

Accepted Answer

The access token is exchanged server-to-server, never exposed to the browser

Answer

The authorization code flow keeps the access token out of the browser by exchanging the short-lived code server-side, preventing token exposure in browser history or logs.

Full-Stack Development Practice Test

Full-Stack Development Practice Test

Full-Stack Development Technology & Digital Applications 5