MEAN Stack Development MCQ 2

Question 1

Which MongoDB operator is used to update a field only if the new value is greater than the current value?

Accepted Answer

$max

Answer

The $max operator updates the field only when the specified value is greater than the existing field value.

Question 2

In Express.js, what does the `next()` function do when called with an error argument like `next(err)`?

Accepted Answer

Invokes the next error-handling middleware

Answer

Calling next(err) skips all remaining non-error middleware and passes control to the next error-handling middleware (which has four parameters: err, req, res, next).

Question 3

In Angular, what is the purpose of the `ChangeDetectionStrategy.OnPush` setting?

Accepted Answer

Limits change detection to when input references change or events are emitted

Answer

OnPush strategy tells Angular to run change detection only when input properties change by reference or an observable emits, improving performance.

Question 4

What does `npm ci` do differently compared to `npm install`?

Accepted Answer

Installs from package-lock.json exactly, deleting node_modules first

Answer

npm ci removes node_modules and installs dependencies exactly as specified in package-lock.json, ensuring reproducible builds.

Question 5

Which Node.js module is used to work with file and directory paths in a cross-platform way?

Accepted Answer

path

Answer

The path module provides utilities for working with file and directory paths, handling differences between POSIX and Windows systems automatically.

MEAN - Stack Development Practice Test

MEAN - Stack Development Practice Test

MEAN Stack Development MCQ 2