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

What tool would you use if you want to save a gif file in mongo?

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?

In which of the following scenarios is sharding not the correct option. Select all that apply.

Consider the following documents:

You perform the following query;

How many documents will be updated by the query?

What is the defau size of a GridFS chunk?

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

Consider the following example document:

{

" _id " : Objectld( " 5360c0a0a655a60674680bbe " ),

" user "

" login " : " irOn "

" description " : " Made of steel "

" date " : ISODate( " 2014-04-30T09:16:45.836Z " ),

}

>

and index creation command:

db.users.createlndex( { " user.login " : 1, " user.date " : -1 }, " mylndex " )

When performing the following query:

db.users.find( { " user.login " : /Air.*/ },

{ " user " :1, " _id " :0 > ).sort( { " user.date " :1 > )

which of the following statements correctly describe how MongoDB will handle the query? Check all that apply.

MongoDB is

What is the maximum size of a MongoDB document

You perform the following operation in the shell: db.foo.insert( { } ); What gets inserted?

Suposse tou have the following collection with only 2 documents:

If you run an aggregation query and use { $unwind: " $traits " } as the first stage, how many documents will be passed to the next stage of the aggregation pipeline?

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

Update If Correct is an approach for which of the following concepts in MongoDB:

Which operations add new documents to a collection?

In a sharded cluster, from which node does one stop the balancer process before initiating backup?

Which type of indexes does MongoDB support?

Which of the following is a valid Replica Set configuration if you want:

1-Have 3 copies of everything

2- That RS3 is never primary

2- 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)

Which of the following aggregation commands in MongoDB does not support sharded collections?

As per the aggregation pipeline optimization concepts, if you have a $sort followed by a $match:

The oplog (operations log) is a special capped collection that keeps a rolling record of all operations that modify the data stored in your databases. All the replica set members contain a copy of the oplog in the following collection:

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

Which of the following is a valid insert statement in mongodb? Select all valid.

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

MongoDB is a schema-less design.

Which of the following collections stores authentication credentials in MongoDB?

You are comparing values of different BSON types in mongodb. You want to compare from lowest to highest. Which comparison order is used?

What is the maximum size of a MongoDB document?

Consider that the posts collection contains an array called ratings which contains ratings given to the post by various users in the following format:

Which of the following query will return all the documents where the ratings array contains elements that in some combination satisfy the query conditions?

What does the following aggregate query perform?

To add a new user and enable authentication in MongoDB, which of the following steps need be executed?

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

A collection and a document in MongoDB is equivalent to which of the SQL concepts respectively?

Write the command(s) are correct to enable sharding on a database " testdb " and shard a collection " testCollection " with _id as shard key.

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?

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

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