laboursonline – MCQs, Mock Tests | MongoDB MongoDB Mcq Question Set 19

Instead of Primary Key mongoDB use?

1. Embedded Documents
2. Default key _id
3. mongod
4. mongofiles

✅ Correct Answer: 2

How to create index in mongoDB?

1. index()
2. createIndex()
3. putIndex()
4. getIndex()

✅ Correct Answer: 2

Which of the following iis correct syntax of createindex?

1. db.COLLECTION_NAME.createIndex({KEY:1})
2. COLLECTION_NAME.createIndex({KEY:1})
3. db.COLLECTION_NAME.createIndex
4. db.createIndex({KEY:1})

✅ Correct Answer: 1

To create index in descending order, the value of key is?

1. 1
2. 0
3. -1
4. infinite

✅ Correct Answer: 3

The default value of background Parameter is :

1. TRUE
2. FALSE
3. 0
4. 1

✅ Correct Answer: 2

The default value of default_language Parameter is :

1. Mongo
2. DB
3. Mongod
4. English

✅ Correct Answer: 4

Which method deletes multiple (specified) indexes on a collection?

1. dropIndexes()
2. dropIndex()
3. Both A and B can be used
4. getIndexes()

✅ Correct Answer: 1

Which method returns the description of all the indexes int the collection?

1. putIndexes()
2. setIndexes()
3. getIndexes()
4. All of the above

✅ Correct Answer: 3

The maximum value of weights parameter is:

1. 999
2. 9999
3. 99999
4. 99

✅ Correct Answer: 3

What is the type of sparse parameter in createIndex()?

1. Boolean
2. string
3. integer
4. Documentation

✅ Correct Answer: 1

What is the type of weights parameter in createIndex()?

1. Boolean
2. string
3. integer
4. Document

✅ Correct Answer: 4

The basic syntax of Aggregation is?

1. db.COLLECTION_NAME.aggregate ({key:1})
2. db.COLLECTION_NAME.aggregation (AGGREGATE_OPERATION)
3. db.COLLECTION_NAME.aggregate (AGGREGATE_OPERATION)
4. aggregate (AGGREGATE_OPERATION)

✅ Correct Answer: 3

Which of th following expression is used to calculates the average of all given values from all documents in the collection?

1. $sum
2. $avg
3. $min
4. $maximum

✅ Correct Answer: 2

Which of th following expression is used to gets the maximum of the corresponding values from all documents in the collection?

1. $sum
2. $push
3. $min
4. $max

✅ Correct Answer: 4

Which of th following expression is used to Inserts the value to an array in the resulting document?

1. $addToSet
2. $first
3. $push
4. $last

✅ Correct Answer: 3

Which of th following expression is used to gets the first document from the source documents according to the grouping?

1. $addToSet
2. $first
3. $push
4. $last

✅ Correct Answer: 2

Which stages in aggregation framework Used to select some specific fields from a collection?

1. $project
2. $group
3. $limit
4. $unwind

✅ Correct Answer: 1

What is true about $unwind stages in aggregation framework ?

1. It is used to unwind document that are using arrays.
2. When using an array, the data is kind of pre-joined and this operation will be undone with this to have individual documents again.
3. This stage we will increase the amount of documents for the next stage.
4. All of the above

✅ Correct Answer: 4

What is true about $group stages in aggregation framework ?

1. This is a filtering operation and thus this can reduce the amount of documents that are given as input to the next stage.
2. This does the actual aggregation
3. Sorts the documents
4. none of the above

✅ Correct Answer: 2

What is true about $skip stages in aggregation framework ?

1. This is a filtering operation and thus this can reduce the amount of documents that are given as input to the next stage.
2. This limits the amount of documents to look at, by the given number starting from the current positions.
3. With this, it is possible to skip forward in the list of documents for a given amount of documents.
4. none of the above

✅ Correct Answer: 3

Which stages in aggregation framework is a filtering operation and thus this can reduce the amount of documents that are given as input to the next stage?

1. $limit
2. $match
3. Both A and B can be used
4. none of the above

✅ Correct Answer: 2

What is true about Replication?

1. Replication is the process of synchronizing data across multiple servers.
2. Replication provides redundancy and increases data availability with multiple copies of data on different database servers.
3. Replication protects a database from the loss of a single server.
4. All of the above

✅ Correct Answer: 4

Replication is not used for?

1. keep your data safe
2. Low availability of data
3. Disaster recovery
4. Read scaling

✅ Correct Answer: 2

Replica set is transparent to the application.

1. TRUE
2. FALSE
3. Can be true or false
4. Can not say

✅ Correct Answer: 1

A replica set is a group of ___________ instances that host the same data set.

1. cluster
2. failover
3. mongod
4. Consensus

✅ Correct Answer: 3

In a replica, one node is primary node that receives?

1. all write operations
2. all read operations
3. all read and write operation
4. None of the above

✅ Correct Answer: 2

Which of the following is not a Replica Set Features?

1. Automatic failover
2. Automatic recovery
3. Consensus election of primary
4. A cluster of only one nodes

✅ Correct Answer: 4

In MongoDB client, how to initiate a new replica set?

1. rs.initiate()
2. rs.conf()
3. rs.status()
4. none of the above

✅ Correct Answer: 1

To check the replica set configuration, issue the command rs.conf().

1. TRUE
2. FALSE
3. Can be true or false
4. Can not say

✅ Correct Answer: 1

Which of the following is correct syntax to Add Members to Replica Set?

1. db.add(HOST_NAME:PORT)
2. rs.add(HOST_NAME:PORT)
3. rs.isMaster(HOST_NAME:PORT)
4. db.isMaster(HOST_NAME:PORT)

✅ Correct Answer: 2

To check whether you are connected to primary or not, issue the command db.Master() in mongo client.

1. TRUE
2. FALSE
3. Can be true or false
4. Can not say

✅ Correct Answer: 2

______ is the process of storing data records across multiple machines and it is MongoDB's approach to meeting the demands of data growth

1. Sharding
2. Config Servers
3. Query Routers
4. Projection

✅ Correct Answer: 1

Single replica set has limitation of?

1. 10 Nodes
2. 12 Nodes
3. 8 Nodes
4. Infinite Nodes

✅ Correct Answer: 2

Which of the following is true about why to use Sharding?

1. In replication, all writes go to master node
2. Memory can't be large enough when active dataset is big
3. Vertical scaling is too expensive
4. All of the above

✅ Correct Answer: 4

In production enviroment , how many sharded clusters have?

1. 2
2. 3
3. 4
4. 5

✅ Correct Answer: 2

What is true about Query Routers?

1. Query routers are basically mongo instances, interface with client applications and direct operations to the appropriate shard.
2. The query router processes and targets the operations to shards and then returns results to the clients.
3. A sharded cluster can contain more than one query router to divide the client request load.
4. All of the above

✅ Correct Answer: 4

Point out the correct statement

1. High query rates can exhaust the CPU capacity of the server
2. Database systems with small data sets and high throughput applications can challenge the capacity of a single server
3. Smaller data sets exceed the storage capacity of a single machine
4. none of the above

✅ Correct Answer: 1

_______ scaling adds more CPU and storage resources to increase capacity.

1. Horizontal
2. Vertical
3. Partition
4. All of the above

✅ Correct Answer: 2

Each shard stores ________ data as the cluster grows.

1. less
2. more
3. equal
4. Can not say

✅ Correct Answer: 1

Which command returns a document that provides an overview of the database process's state?

1. serverStatus
2. currentQueue
3. currentQu
4. clientStatus

✅ Correct Answer: 1

Which of the following setting defines what constitutes a "slow" operation?

1. fastOpThresholdMs
2. slowOpThresholdZs
3. slowOpThresholdMs
4. slowOpThresholdGs

✅ Correct Answer: 3

_____ returns the queryPlanner information for the evaluated method.

1. db.explain()
2. db.collection.explain()
3. collection.explain()
4. explain()

✅ Correct Answer: 2

Point out the correct statement.

1. For read-heavy applications, deploy sharding and add one or more shards to a sharded cluster to distribute load among mongod instances
2. Spikes in the number of available connections can also be the result of application or driver errors
3. For read-heavy applications, increase the size of your replica set and distribute read operations to secondary members
4. All of the above

✅ Correct Answer: 3

With which storage engine, MongoDB uses memory-mapped files to store data?

1. MMAPv2
2. MMAPv1
3. WiredTiger
4. All of the above

✅ Correct Answer: 2

_____ returns the queryPlanner and executionStats information for the evaluated method.

1. cursor.explain()
2. tablescan.explain()
3. server.explain()
4. client.explain()

✅ Correct Answer: 1

If MongoDB can use an index scan to obtain the requested sort order, the result will not include a SORT stage

1. TRUE
2. FALSE
3. Can be true or false
4. Can not say

✅ Correct Answer: 2

In MongoDB, At which level write operations are atomic?

1. Collection
2. Document
3. Field
4. RowSet Interface

✅ Correct Answer: 2

The limit on the number of namespaces depend on the ?

1. <database>.ns size
2. <document>.ns size
3. <field>.ns size
4. . <row>.ns size

✅ Correct Answer: 1

The namespace file defaults to ?

1. 4 MB
2. 8 MB
3. 16 MB
4. 32 MB

✅ Correct Answer: 3

_____index allows efficient retrieval of chunks using the files_id and n values.

1. repairDatabase
2. dataFS
3. fileFS
4. GridFS

✅ Correct Answer: 4