MEAN Stack Development 2

Question 1

In a MEAN stack app, which Angular decorator is used to define a component's metadata such as its template and selector?

Accepted Answer

@Component

Answer

@Component decorator marks a class as an Angular component and provides configuration metadata including selector, template, and styles.

Question 2

Which MongoDB operator is used to update only specific fields in a document without replacing the entire document?

Accepted Answer

$set

Answer

The $set operator updates only the specified fields in a document, leaving all other fields unchanged.

Question 3

What is the purpose of Express.js middleware's `next()` function?

Accepted Answer

Passes control to the next middleware function

Answer

Calling next() passes control to the next middleware in the stack; without it, the request-response cycle would hang.

Question 4

In Node.js, what does the `EventEmitter` class primarily enable?

Accepted Answer

Asynchronous event-driven communication between objects

Answer

EventEmitter allows objects to emit named events and register listener functions that respond to those events asynchronously.

Question 5

Which of the following correctly describes a Mongoose 'virtual' field?

Accepted Answer

A computed property that is not persisted to the database

Answer

Mongoose virtuals are properties computed from existing document data at runtime and are not saved to MongoDB.

MEAN - Stack Development Practice Test