C100DBA MongoDB Certified DBA Associate Exam (Based on MongoDB 4.4) Questions and Answers

specify {all: true} as the third parameter of update command

updateAII instead of update

specify {updateAII: true} as the third parameter of update command

specify {multi : true} as the third parameter of update command

JSON

BSON

B+ Trees

JSON - Extended

200, more

No limit, none

20, it

50, it

db.collection.update({b:456>, {$inc: {a:l> })

db.collection.find( {a : 232} )

db.collection.insert( { a:341})

Number of documents that match the query condition

Number of index entries scanned

Details the completed execution of the winning plan as a tree of stages

Number of documents scanned

7

03

04

06

mongotop

dbstats

mongostat

constats

db.stopBalancer( )

sh.stopServer( )

db.stopServer( )

sh.stopBalancer( )

db.posts.createIndex({^comments.$.author":-l});

db. posts.createIndex({^comments.author" :1});

db.posts.createIndex({^commerits.author";-!});

Two documents will be inserted with _id as 1

MongoDB will automatically increment the _id of the second document as 2

This will throw a duplicate key error

It will insert two documents and throw a warning to the user

db.posts.createIndex({commerits.$.author":-l});

db.posts.createIndex({comments.$.author": {$desc:l>});

db.posts.createIndex({comments.author":-l});

Code block

Name/value pair

Key

None of the above

0

1

2

3

5

The write operations on the collection are low

The write operations on the collection are very high

The working set in the collection is expected to grow very large in size

The collection is a read intensive collection with less working set

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

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

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

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

Multi-statement transactions

Joins

Authentication