MongoDB C100DBA Exam Practice Test Instant Access

Question 1

Consider that you have a collection called population which has fields state and city. Which of the following query will calculate the population grouped by state and city?

Adb.population.aggregate( [{ $group: { _id: { state: '$state', city: '$city' },pop: { $pop: 1 } } }] )

Bdb.population.aggregate( [{ $group: { _id: { city: '$city' },pop: { $sum: '$pop' } } }] )Multi Document Transaction is not supported by MongoDB

Cdb.population.aggregate( [{ $group: { _id: { state: Estate', city: '$city' },pop: { $sum: '$pop' } } }] )

Ddb.population.aggregate( [{ $group: { _id: { state: Estate', city: '$city' },pop: { $sum: 1 > > >] )

Answer : C

Question 2

Which command is used to determine storage capacity of specific database?

Amongotop

Bdbstats

Cmongostat

Dconstats

Answer : B

Question 3

When should we consider representing a one-to-many relationship in an embedded collection instead of separate collection?

AWhen the many is not very large

BWhen the many is very large

CAlways

DNever

Answer : A

Question 4

Which node in a replica set does accept write operation?

Aarbiter

Bhidden

Cprimary

Dsecondary

Answer : C

Question 5

You are in a sharded cluster. What will you do prior to initiating backup in sharded cluster?

Adb.stopBalancer()

Bdb.stopserver()

Csh.stopBalancer()

Dsh.stopserverQ

Answer : C

Question 6

Consider that you have a collection called population which has fields state and city. Which of the following query will calculate the population grouped by state and city?

Adb.population.aggregate( [{ $group: { _id: { state: '$state', city; '$city' },pop: { $sum: 1 > > >] )

Bdb.population.aggregate( [{ $group: { _id: { state: Estate', city: '$city' },pop: { $pop: 1 } } }] )

Cdb.population.aggregate( [{ $group: { _id: { state: Estate', city: n$city' },pop: { $sum: '$pop' } } }] )

Ddb.population.aggregate( [{ $group: { _id: { city: '$city' },pop: { $sum: '$pop' } } }] )Multi Document Transaction is not supported by MongoDB

Answer : C

Question 7

In what format does mongodump creates backup files?

ABSON

BJSON

CSOAP

DXML

Answer : A

MongoDB C100DBA MongoDB Certified DBA Associate Exam Practice Test