Free MongoDB Certified DBA Associate Exam C100DBA Exam Practice Test

'$set' sets the value of

• Code block
• Name/value pair
• Key
• None of the above

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?

• 7
• 2
• 1
• 0

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.

• $aggregate
• $sum
• $match
• $group

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

• primary
• arbiter
• hidden
• secondary

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.

• As an optimized sort query (scanAndOrder = false) using 'mylndex' because we are sorting on an indexed field
• As an indexed query using 'mylndex' because field 'user.login' is indexed
• MongoDB will need to do a table/collection scan to find matching documents
• None of the above
• As a covered query using 'mylndex' because we are filtering out '_id' and only returning 'user.login'

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})

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

• Any node
• replicaset primary node
• config server node
• mongos node

Which of the following command is used to get all the indexes on a collection?

• db.collection.showIndexes()
• db.collection.findlndexes()
• db.showIndexes()
• db.collection.getlndexesQ

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

Which of the following collections stores authentication credentials in MongoDB?

• test.users
• local.users
• system.users
• users.users