MongoDB MongoDB Certifications C100DBA Questions & Answers

• Question 21:

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

  A. mongotop

  B. dbstats

  C. mongostat

  D. constats

  Correct Answer: B

• Question 22:

  Which of the following is true of the mechanics of replication in MongoDB? Check all that apply.

  A. Members of a replica set may replicate data from any other data-bearing member of the set by default

  B. Clients read from the nearest member of a replica ser by default

  C. Operations on the primary are recorded in a capped collection called the oplog

  Correct Answer: C

• Question 23:

  Which of the following are valid json documents? Select all that apply.

  A. {"a":l, "b":{"b":l, "c":"foo", "d":"bar", "e":[l,2,4]}}

  B. {"city":"New York", "population", 7999034, boros:{"queens", "manhattan", "staten island", "the bronx", u "brooklyn"}}

  C. {"name":"Fred Flintstone";"occupation":"Miner";"wife":"Wilma"}

  D. { }

  Correct Answer: AD

• Question 24:

  What does the following $slice query return using the following command? db.posts.find( {}, { comments: { $slice: [ -10, 5 ] } } )

  A. Returns 5 comments, beginning with the last 10 items

  B. Returns 10 comments, beginning with the last

  C. Returns 10 comments, beginning with the first

  D. Returns 5 comments, beginning with the first 10 items

  Correct Answer: A

• Question 25:

  Which of the following command inside aggregate command is used in MongoDB aggregation to filter the documents to pass only the documents that match the specified condition(s) to the next pipeline stage.

  A. $aggregate

  B. $sum

  C. $match

  D. $group

  Correct Answer: C

• Question 26:

  In mongodb how do you update a document partially?

  A. $project

  B. $update

  C. $modify

  D. $set

  Correct Answer: D

• Question 27:

  What is the output of following two commands in MongoDB: db. posts. insert({n_id":l}) db.posts.insert ({"_id":l})

  A. Two documents will be inserted with _id as 1

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

  C. This will throw a duplicate key error

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

  Correct Answer: C

• Question 28:

  MongoDB is a schema-less design.

  A. False

  B. True

  Correct Answer: B

• Question 29:

  What is the maximum size of Index Key Limit and Number of Indexes per collection?

  A. 1024 bytes and 64 indexes

  B. 12 mega bytes and 64 indexes

  C. 64 bytes and 1024 indexes

  D. 1024 bytes and unlimited indexes

  Correct Answer: A

• Question 30:

  What is the on-premise solution having functionality equivalent to cloud manager?

  A. Service Manager

  B. Replica Manager

  C. Ops Manager

  D. Journaling

  Correct Answer: C