C100DBA Exam Dumps - MongoDB Certified DBA Associate Exam (Based on MongoDB 4.4)

db.posts.find( { tags : ["tutorial"] } );

db.posts.find( { $array : {tags: "tutorial") > );

db.posts.find( { tags : "tutorial" } );

db.posts.findInArray( { tags : "tutorial" > );

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

secondaryPreferred

Secondary

nearest

primary

primaryPreferred

BSON

JSON

SOAP

XML

findQ returns all the documents in a collection while findOne() retrieves only the first one.

find.limit(l) is not the same query as findOne()

findOneQ returns the actual first document retrieved from a collection

findQ and findOneQ returns cursors to the collection documents

Returns the complete document but retrieves only the size field from the array

Returns the document but with only one element in the variations array (corresponding to size L)

Returns the complete document since MongoDB does not support partial array retrieval

Returns the complete document but retrieves only the size field from the array and also with only one element in the variations array (corresponding to size L)

Syntax error

Replaces the complete document with _id as 1 with the document specified in second parameter

Updates the Title of the post

Updating a document is possible only with $set

Sharding

Properly defined user roles

Replication

Put indexes on all of your documents

The proper storage engine

executionStats

queryPlanner

customExecutionStats

allPlansExecution

Providing these parameters in any order does not impact the performance

$sort moves before $match

MongoDB does not do any movements by default and will use the order provided

$match moves before $sort

Even

Odd

2

Depends on the application architecture

Fetches the posts with likes between 100 and 200 and sets their _id as null

Groups the posts by number of likes (101, 102, 103.) by adding 1 every time

Calculates the number of posts with likes between 100 and 200

Fetches the posts with likes between 100 and 200, sets the _id of the first document as null and then increments it 1 every time

$addToSet needs the fields to be already present while $push will work even if the field is not present

$addToSet adds the item to the field only if it does not exist already; while $push pushes the item to the field irrespective of whether it was present or not

$addToSet adds the item to the field only if the new item is of the same datatype

There is no major difference between them. $addToSet is a deprecated version of $push.

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

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

Create

update

insert

delete