Question No : 1
We have an accounts collection with only one document:
{
_id: 54657,
account_id: 557378,
products: [ 'InvestmentStock', 'Commodity', 'CurrencyService' ]
}
We need to use Aggregation Framework to unwind the products Array to obtain new documents with
only one product per document (see below).
Expected output:
[
{ _id: 54657, account_id: 557378, products: 'InvestmentStock' },
{ _id: 54657, account_id: 557378, products: 'Commodity' },
{ _id: 54657, account_id: 557378, products: 'CurrencyService' }
]
Which pipeline should you use?

• A.[{ $facet: { path: "$products", } }]
• B.[{ $unwind: { path: "$products", } }]
• C.[{ $unset: { path: "$products", } }]
• D.[{ $project: { path: "$products", } }]

Show Answers

Answer:
Explanation:
https://docs.mongodb.com/manual/reference/operator/aggregation/unwind/

Question No : 2
Which of the following commands will delete a collection named restaurants?

• A.db.restaurants.dropCollection()
• B.db.restaurants.delete()
• C.db.restaurants.remove()
• D.db.restaurants.drop()

Show Answers

Answer:
Explanation:
https://docs.mongodb.com/manual/reference/method/db.collection.drop/

Question No : 3
Select all true statements regarding to the role of fields and values in a MongoDB document. (select 2)

• A.A field is a unique identifier for a specific data point.
• B.You can have duplicate field names within the same level of a single document.
• C.Values don't need to be attached to fields and can be standalone data points.
• D.Each field has a value associated with it.

Show Answers

Answer:
Explanation:
https://docs.mongodb.com/manual/core/document/

Question No : 4
Which of the following commands will successfully insert exactly two new documents into an empty companies collection?

• A.db.companies.insertMany([ {"_id": 1, "name": "Facebook"}, {"_id": 1, "name": "Twitter"}, {"_id": 2, "name": "Tesla"} ], {"ordered": false})
• B.db.companies.insertMany([ {"_id": 1, "name": "Facebook"}, {"_id": 1, "name": "Twitter"}, {"_id": 2, "name": "Tesla"} ])
• C.db.companies.insertMany([ {"_id": 1, "name": "Facebook"}, {"_id": 2, "name": "Twitter"} ]) D, db.companies.insertMany([ {"_id": 1, "name": "Facebook"}, {"_id": 2, "name": "Twitter"}, {"_id": 2, "name": "Tesla"} ])
• D.db.companies.insertMany([
• E.{"name": "Facebook"},
• F.{"name": "Twitter"}
• G.])

Show Answers

Answer:
Explanation:
https://docs.mongodb.com/manual/reference/method/db.collection.insertMany/

Question No : 5
Which of the following methods executes a database command? (mongo shell)

• A.db.execute({ <command> })
• B.db.ommand({ <command> })
• C.db.runCommand({ <command> })
• D.db.runThisCommand({ <command> })

Show Answers

Answer:
Explanation:
https://docs.mongodb.com/manual/reference/method/db.runCommand/

Question No : 6
You have the following index in a movies collection:
{ "title": 1, "imdb.rating": -1, "imdb.votes": -1, "type": 1 }
Can the following query use the given index for both filtering and sorting?

• A.db.movies.find( { "imdb.rating": 8, "title": "James Bond" } ).sort( { "imdb.votes": -1 } )
• B.Yes
• C.No

Show Answers

Answer:
Explanation:
Yes, this query can use the index prefix. The order of the fields in the query predicate does not matter.
Since both "imdb.rating" and "title" are part of an index prefix, this query can use the index for an equality condition.
https://docs.mongodb.com/manual/indexes/

Question No : 7
Suppose you insert the following documents into companies collection:
db.companies.insertMany([
{"_id": 1, "name": "Facebook"},
{"_id": 1, "name": "Twitter"},
{"_id": 2, "name": "Tesla"},
{"_id": 3, "name": "Amazon"}
], {"ordered": false})
Select all true statements about this operation. (select 3)

• A.Two documents will be inserted into the collection.
• B.This insert is unordered.
• C.Three documents will be inserted into the collection.
• D.MongoDB will insert each document with a unique _id value into the collection.
• E.One document will be inserted into the collection.

Show Answers

Answer:
Explanation:
https://docs.mongodb.com/manual/reference/method/db.collection.insertMany/

Question No : 8
What does it command do in the mongo shell?

• A.Iterates through the cursor results.
• B.Terminates the current query execution.
• C.it is not a mongo shell command.
• D.Displays cluster statistics.

Show Answers

Answer:

Question No : 9
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
},
{
_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
}
What is the default sort order in the result set returned in response to the following query?

• A.db.companies.aggregate( [ { "$sortByCount": "$category_code" } ] )
• B.ascending
• C.descending

Show Answers

Answer:
Explanation:
https://docs.mongodb.com/manual/reference/operator/aggregation/sortByCount/

Question No : 10
Select all options when you should deploy a MongoDB deployment with security enabled.

• A.Deployment of the development environment.
• B.Deployment of the evaluation environment.
• C.Deployment of the staging environment.
• D.Deployment of the production environment.

Show Answers

Answer:
Explanation:
https://docs.mongodb.com/manual/reference/configuration-options/#security-options