MongoDB Certified DBA Associate Exam C100DBA Exam Questions

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To be a MongoDB certified, you’re achieving the same level of expertise that we require our own administrators to attain. C100DBA exam questions have been released online to help candidates prepare for MongoDB Certified DBA Associate Exam (Based on MongoDB 4.4) exam well. The latest C100DBA exam questions from ITExamShop are the best in the whole market, which are valid for passing MongoDB DBA Associate exam. No need others to do, just read C100DBA exam questions with the easy pdf file and free software engine. We ensure that you can complete MongoDB Certified DBA Associate Exam in the first attempt.

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1. Which features of relational database management systems were deliberately omitted in MongoDB and help us to obtain horizontal scalability? Check all that apply.

Multi-statement transactions

Joins

Authentication

2. The following aggregation option is used to specify the specific fields that needs to be passed to the next stage of the aggregation pipeline:

$project

$aggregate

$match

$group

3. In a collection that contains 100 post documents, what does the following command do? db. posts. find().skip(5).limit(5)

Skip and limit nullify each other. Hence returning the first five documents.

Skips the first five documents and returns the next five

Limits the first five documents and then return them in reverse order

Skips the first five documents and returns the sixth document five times

4. CORRECT TEXT

What tool do you use to see if you have a problem in the consumption of disk I / 0?

5. Which of the following is supported by MongoDB?

Transaction Management

ACID Transactions

Journaling

Relationships between Collections (Primary Key Foreign Key)

6. The MongoDB explain() method does not support which of the following verbosity mode:

executionStats

queryPlanner

customExecutionStats

allPlansExecution

7. Consider a collection posts which has fields: Jd, post_text, post_author, post_timestamp, post_tags etc.

Which of the following query retrieves ONLY the key named post_text from the first document retrieved?

db.posts.finOne({},{_id:0, post_text:1})

db.posts.findOne({post_text: 1})

db.posts.find({},{_id:Of post_text:1})

db.posts.finOne«},{post_text:l})

8. In a sharded replica set environment, the w Option provides ability for write concern and j Option provides ability for the data to be written on disk journal. Consider that we have a seven member replica set and we want to assure that the writes are committed to journal.

What should be the value of j?

9. Aggregation Pipelines have a limit of:

2 MB document and 100 MB RAM

16 MB document and 100 MB RAM

No limit on document and 100 MB RAM

2 MB document and no limit on RAM

10. What is the maximum size of a MongoDB document?

2 MB

12 MB

There is no maximum size. It depends on the RA

16 MB

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11. If the value of totalKeysExamined is 30000 and the value of totalDocsExamined is 0, which of the following option is correct?

None of the above

The query used an index to fetch the results

The query returned 0 documents

The query returned 30000 documents after scanning the documents

12. Given a collection posts as shown below having a document array comments, which of the following command will create an index on the comment author descending?

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

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

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

13. Which option should be used to update all the documents with the specified condition in the MongoDB query?

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

14. Which mongodb tool is used to report details on number of database operations in MongoDB?

mongorestore

mongostat

mongodump

mongotop

15. In a sharded replica set environment, the w Option provides ability for write concern and j Option provides ability for the data to be written on disk journal. Consider that we have a seven member replica set and we want to assure that the writes are committed to journal.

What should be the value of j?

16. What read preference should your application use if you want to read from the primary under normal circumstances but allow reads from secondaries when a primary is unavailable?

secondaryPreferred

Secondary

nearest

primary

primaryPreferred

17. Which of the following operators is used to updated a document partially?

$set

$update

$project

$modify

18. What is the first task that a secondary would perform on being prompted by another secondary for an election?

Start the election process for primary

Vote for the first secondary so that it would become the next primary

Vote for itself and then call for election

Connect to primary to confirm its availability

19. Which of the documents below will be retrieved by the following query? Assume the documents are stored in a collection called "sample". Check all that apply.

db.sample.find( { "$or" : [ { "a" : { "$in" : [ 3, 10] > }, { "b" : { "$lt" : 2 > > ] > )

{''__id" :3, "a": 4, "c" :0, "b" :14}

{''_Jd" :7, "a": 8, "c" :1, "b" :7}

{".Jd" :6, "a": 1, "c" :1, "b" :5}

{ ''Jd" :9, "a": 17, "c": 1, "b": 1}

{ Jd" :10,"a": 3, "c": 1, "b": 1}

{".Jd" :: 2, "a": 2, "c" :: 0, "b": 1}

{".Jd" :: 4, "a": 5, "c" :: 0, "b": 17}

{".Jd" :: 1, "a": 0, "c" :: 0, "b": 2}

{".Jd" :: 5, "a": 3, "c" :: 0, "b": 12}

{".Jd" :: 8, "a": 11, "c": 1, "b": 0}

20. JSON stands for

JavaScript Object Notation

JavaScript Object Naming

JavaScript Object Notice

None of the above

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21. What is the replication factor for a replicated cluster with 1 primary, 3 secondaries with one of them hidden. The set also has an arbiter?

None of the above

22. Which operations add new documents to a collection?

Create

update

insert

delete

23. 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?

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

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

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

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

24. Which of the following is true about sharding?

Creating a sharded key automatically creates an index on the collection using that key

We cannot change a shard key directly/automatically once it is set up

A sharded environment does not support sorting functionality since the documents lie on various mongod instances

Sharding is enabled at the database level

25. Which of the tags in a replica set configuration specify the operations to be read from the node with the least network latency?

netLatency

secondaryPreferred

nearest

primaryPreferred

26. What is the output of the following program?

60 s

100 s

100 ms

27. Which node in a replica set does accept write operation?

arbiter

hidden

primary

secondary

28. Using an arbiter allows one to easily ensure an odd number of voters in replica sets.

Why is this important?

To help in disaster recovery

To protect agains network partitions

To enable certain read preference settings

To add greather redundancy

For more efficient backup operations

29. Which of the following statements are true about the $match pipeline operator? Check all that apply.

You should use it early as possible in the pipeline

It can be used as many time as needed.

It has a sintax similar to findQ commands.

30. That RSI and RS2 can be primary?

You had to see the different configurations, RS3 could be hidden or priority 0 (But not a referee because we need 3 replicas), while RSI and RS2 could NOT have priority 0 or be hidden or anything like that .

In a 4-member RS RSO, RSI, RS2 and RS3 + Referee, RSO (primary) falls after some write operations that have replicated RSI and RS2 (but NOT RS3), who can get up as the new primary?

The configuration comes and in it we see that RS2 has a hidden: true (or a priority: 0, (I don't remember)

ORS1

ORS2

ORS3

O arbiter

RSO

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31. Given a replica set with five data-bearing members, suppose the primary goes down with operations in its oplog that have been copied from the primary to only one secondary.

Assuming no other problems occur, which of the following describes what is most likely to happen?

missing operations will need to be manually re-performed

the secondary with the most current oplog will be elected primary

reads will be stale until the primary comes back up

the primary may roll back the operations once it recovers

the most current secondary will roll back the operations following the election

32. Which command can be used to rebuild the indexes on a collection in MongoDB?

db.collection.createlndex({relndex:l})

db.collection.reIndex({author:l})

db.collection.relndexQ

db.collection.createIndex({author:l}).reIndex()

33. What does the totalKeysExamined field returned by the explain method indicate?

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

34. In order to ensure that you can maintain high availability in the face of server failure, you should implement which of the following?

Sharding

Properly defined user roles

Replication

Put indexes on all of your documents

The proper storage engine

35. Which option can be used with update command so that a new document gets created if no matching document is found based on the query condition?

upsert command instead of update command

{update: true, insert: true} as the third parameter of update command

This has to be handled in application code (Node.js, PHP, JAVA, C#, etc.) and cannot be handled in mongo shell query

Specify {upsert : true } as the third parameter of update command

36. Dada una coleccion, cuales devuelve con la siguiente query db.coleccion.find({nombre:"ruben",apellido:"gomez"},{nombre:l,apellido:l,aficion:l});

{ "-id" : Objectld("580a42b5dfblb5al7427d302"), "nombre" : "ruben", "apellido" : "gomez", "aficion" : v u "flipar" }

{ "_id" : Objectld("580a42acdfblb5al7427d301"), "nombre" : "Luis", "apellido" : "gomez", "aficion" : u "flipar" }

{ "_id" : Objectld("580a42acdfblb5al7427d301"), "nombre" : "ruben", "apellido" : "Pablo", "aficion" : u "flipar"}

{ "_id" : Objectld("580a42acdfblb5al7427d301"), "nombre" : "ruben", "apellido" : "gomez">

37. MongoDB is

None of the above

Object-oriented DBMS

Relational DBMS

Document-oriented DBMS

38. Which are the ONLY ways to project portions of an array?

$slice

All of the above

$ elemMatch

39. In a replicated cluster, which of the following node would only be used during an election?

arbiter

primary

hidden

secondary

40. Which of the following node is used during election in a replication cluster?

primary

arbiter

hidden

secondary

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MongoDB Certified DBA Associate Exam C100DBA Exam Questions

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