Quiz about Exam Dumps, MongoDB, MongoDB-C100DEV

Question 1

Suppose you have a sales collection with the following document structure:  { 
_id: ObjectId(\"5bd761dcae323e45a93ccfe8"), 
saleDate: ISODate("2015-03-23T21:06:49.506Z"), 
items: [ 
{ 
name: 'printer paper', 
tags: [ 'office', 'stationary' ], 
price: Decimal128("40.01"), 
quantity: 2 
} 
{ 
name: 'pens', 
tags: [ 'writing', 'office', 'school', 'stationary' ], 
price: Decimal128("56.12"), 
quantity: 5 
}, 
{ 
name: 'notepad', 
tags: [ 'office', 'writing', 'school' ], 
price: Decimal128("18.47"), 
quantity: 2 
} 
], 
storeLocation: 'Denver', 
couponUsed: true, 
purchaseMethod: 'Online' 
} 
Which of the following queries will return all document sales with 'printer paper' sold?

Accepted Answer

db.sales.find( { items: { $elemMatch: { name: 'printer paper' } } } )

Answer

db.sales.find( { items: { $match: { name: 'printer paper' } } } )

Answer

db.sales.find( { items: { elemMatch: { name: 'printer paper' } } } )

Question 2

Select true statement regarding to the MongoDB Atlas. (select 1)

Accepted Answer

MongoDB Atlas includes many tools and services specifically designed for the MongoDB database.

Answer

MongoDB Atlas is a MongoDB service that can work with any database.

Question 3

In your database there is a collection named companies with the following document structure:  { 
name: 'Wize', 
relationships: [ 
{ 
is_past: false, 
title: 'Head of Product', 
person: { 
first_name: 'Ethan', 
last_name: 'Smith', 
permalink: 'ethan-smith' 
} 
}, 
{ 
is_past: true, 
title: 'Director, Business Development', 
person: { 
first_name: 'Stephanie',

last_name: 'Quay', 
permalink: 'stephanie-quay' 
} 
}, 
{ 
is_past: true, 
title: 'Sr. Engineer', 
person: { 
first_name: 'Stefan', 
last_name: 'Antonowicz', 
permalink: 'stefan-antonowicz' 
} 
} 
] 
} 
Which of the following queries should you use to extract all companies that have \"Co-Founder" title in 
relationships field (Array)?

Accepted Answer

db.companies.find( { relationships: { $elemMatch: { title: 'Co-Founder' } } } )

Answer

db.companies.find( { relationships: { $eq: { title: 'Co-Founder' } } } )

Answer

db.companies.find( { relationships: { $match: { title: 'Co-Founder' } } } )

Question 4

In your database there is a movies collection with the following document structure:  { 
_id: ObjectId(\"573a1390f29313caabcd42e8"), 
genres: [ 'Short', 'Western' ], 
title: 'The Great Train Robbery', 
rated: 'TV-G', 
year: 1903, 
imdb: { rating: 7.4, votes: 9847, id: 439 }, 
countries: [ 'USA' ] 
}, 
{ 
_id: ObjectId("573a1390f29313caabcd4323"), 
genres: [ 'Short', 'Drama', 'Fantasy' ], 
rated: 'UNRATED', 
title: 'The Land Beyond the Sunset', 
year: 1912, 
imdb: { rating: 7.1, votes: 448, id: 488 }, 
countries: [ 'USA' ] 
} 
In some documents, where there is no rating information for movie, the value is set to '' (empty string). 
With that in mind, which of the following queries will return the title and rating (see below) of top 3 rated 
movies in this collection?

Accepted Answer

db.movies.find(      { 'imdb.rating': { $ne: '' } }, 
    { _id: 0, title: 1, 'imdb.rating': 1 } 
).sort( { 'imdb.rating': -1 } ).limit(3)

Answer

db.movies.find(     { 'imdb.rating': { $ne: '' } }, 
    { _id: 0, title: 1, 'imdb.rating': 1 } 
).sort( { 'imdb.rating': 1 } ).limit(3)

Answer

db.movies.find(     {}, 
    { _id: 0, title: 1, 'imdb.rating': 1 }
).sort( { 'imdb.rating': 1 } ).limit(3)

Answer

db.movies.find(      { 'imdb.rating': { $eq: '' } }, 
    { _id: 0, title: 1, 'imdb.rating': 1 } 
).sort( { 'imdb.rating': -1 } ).limit(3)

Question 5

Select all true statements regarding to the _id field in MongoDB documents. (select 4)

Accepted Answer

When inserting a document, the _id value is already generated as an ObjectId type, if not directly specified.

Accepted Answer

MongoDB adds an _id field to any inserted document if it doesn't have one.

Accepted Answer

We can select a non ObjectId type value for _id field when inserting a new document.

Accepted Answer

The _id values must be unique for the collection.

Answer

The _id can be an array data type.

Question 6

Suppose you have a companies collection in your database. Only the following documents are stored in  this collection: 
{ 
_id: ObjectId(\"52cdef7c4bab8bd675297da4"), 
name: 'Powerset', 
category_code: 'search', 
founded_year: 2006 
}, www.dumpsplanet.com

{ 
_id: ObjectId("52cdef7c4bab8bd675297da5"), 
name: 'Technorati', 
category_code: 'advertising', 
founded_year: 2002 
}, 
{ 
_id: ObjectId("52cdef7c4bab8bd675297da7"), 
name: 'AddThis', 
category_code: 'advertising', 
founded_year: 2004 
}, 
{ 
_id: ObjectId("52cdef7c4bab8bd675297da8"), 
name: 'OpenX', 
category_code: 'advertising', 
founded_year: 2008

}, 
{ 
_id: ObjectId("52cdef7c4bab8bd675297daa"), 
name: 'Sparter', 
category_code: 'games_video', 
founded_year: 2007 
}, 
{ 
_id: ObjectId("52cdef7c4bab8bd675297dac"), 
name: 'Veoh', 
category_code: 'games_video', 
founded_year: 2004 
}, 
{ 
_id: ObjectId("52cdef7c4bab8bd675297dae"), 
name: 'Thoof', 
category_code: 'web', 
founded_year: 2006 
} 
How many documents will be deleted when executing the following query?

Accepted Answer

3

Answer

db.companies.deleteMany( { \"category_code": "advertising" } )

Answer

7

Answer

0

Answer

4

Question 7

Which of the following commands can you use to exports data in BSON format from a MongoDB cluster?

Accepted Answer

mongodump

Answer

mongoexport

Answer

mongostore

Answer

mongoimport

Question 8

Suppose you have a developers collection with only two documents:

{ 
_id: 1, 
lname: 'Smith', 
tech_stack: [ 'sql', 'git', 'python', 'django' ], 
fname: 'Bob' 
}, 
{ 
_id: 2, 
fname: 'Michael', 
lname: 'Doe', 
tech_stack: [ 'git', 'python', 'sqlite', 'linux', 'flask' ] 
} 
Using Aggregation Framework you run the following stage: 
{ 
$unwind: { 
path: '$tech_stack' 
} 
} 
How many documents will you have in the pipeline after the $unwind stage?

Accepted Answer

9

Answer

2

Answer

7

Answer

5

Answer

4

Question 9

Select all true statements about auto bucketing feature in Aggregation Framework. ($bucketAuto stage)

Accepted Answer

This stage distributes documents evenly across predefined number of buckets.

Accepted Answer

The granularity option allows us to specify preferred bucket boundaries.

Accepted Answer

The syntax for this stage is as follows:

Question 10

A collection called players contains the following documents:  [ 
{ _id: 1, user: 'Tom', scores: [ 23, 56, 3, 52, 62 ], bonus: 5 }, 
{ _id: 2, user: 'Jane', scores: [ 42, 50, 10 ], bonus: 3 } 
] 
You want to add additional fields to each document:

-> total_score (sum of the scores Array) 
-> avg_score (average score in scores Array) 
-> total_score_with_bonus (total_score + bonus) 
Expected output: 
[ 
{ 
_id: 1, 
user: 'Tom', 
scores: [ 23, 56, 3, 52, 62 ], 
bonus: 5, 
total_score: 196, 
avg_score: 39.2, 
total_score_with_bonus: 201 
}, 
{ 
_id: 2, 
user: 'Jane', 
scores: [ 42, 50, 10 ], 
bonus: 3, 
total_score: 102, 
avg_score: 34, 
total_score_with_bonus: 105 
} 
] 
Which query do you need to use?

Accepted Answer

db.players.aggregate([{     $addFields: {
        total_score: {
            $sum: '$scores'
        },
        avg_score: {
            $avg: '$scores'
        }
    }
}, {
    $addFields: {
        total_score_with_bonus: {
            $add: ['$total_score', '$bonus']
        }
    }
}])

Answer

db.players.aggregate([{     $addFields: {
        total_score: {
            $sum: '$scores'
        },
        avg_score: {
            $avg: '$scores'
        },
        total_score_with_bonus: {
            $add: ['$total_score', '$bonus']
        }        
    }
}])

Quiz MongoDB-C100DEV

Free Test - Simulator MongoDB-C100DEV

MongoDB-C100DEV Practice test unlocks all online simulator questions

What to expect from our MongoDB-C100DEV practice tests and how to prepare for any exam?