MEAN MongoDB Advanced Operations 4

Question 1

Which MongoDB operator is used to perform a bitwise AND update on a field?

Accepted Answer

$bit with 'and'

Answer

The $bit operator with the 'and' key performs a bitwise AND update on integer fields in MongoDB.

Question 2

What does the MongoDB $facet aggregation stage allow you to do?

Accepted Answer

Run multiple aggregation pipelines within a single stage on the same input

Answer

$facet enables multi-faceted aggregations by processing multiple sub-pipelines on the same set of input documents in one pass.

Question 3

In MongoDB's change streams, what does the 'fullDocument' option set to 'updateLookup' do?

Accepted Answer

Returns the full document after an update by performing an extra lookup

Answer

Setting fullDocument to 'updateLookup' causes MongoDB to perform an additional query to return the full post-update document alongside the change event.

Question 4

Which read concern level guarantees that data has been written to a majority of replica set members before being read?

Accepted Answer

majority

Answer

The 'majority' read concern ensures that the data read has been acknowledged by a majority of replica set members, preventing rollback.

Question 5

What is the purpose of the MongoDB $bucket aggregation stage?

Accepted Answer

Categorizes documents into user-defined ranges (buckets) based on a field value

Answer

$bucket groups incoming documents into contiguous, user-specified ranges and counts (or computes) values within each range.

MEAN - Stack Development Practice Test

MEAN - Stack Development Practice Test

MEAN MongoDB Advanced Operations 4