JOBSEEKERS
Login
Sign Up
Jobseeker
Employer
Staffing Firm
Direct Firm
MongoDB interview questions part 2
MongoDB interview questions part 2
Back
Take as many assements as you can to improve your validate your skill rating
Total Questions: 20
1. Pipeline stages can use __________ for tasks such as calculating the average or concatenating a string.
A. replicas
B. operators
C. roles
D. all of the mentioned
Show Correct Answer
Correct Answer is :
operators
2. Map-reduce uses custom __________ functions to perform the map and reduce operations.
A. Java
B. Javascript
C. JSON
D. None of the mentioned
Show Correct Answer
Correct Answer is :
Javascript
3. Which of the following operation can be optionally used for map reduce ?
A. finally
B. final
C. static
D. none of the mentioned
Show Correct Answer
Correct Answer is :
finally
4. The aggregation pipeline can use ___________ to improve its performance during some of its stages.
A. indexes
B. OptmData
C. functions
D. all of the mentioned
Show Correct Answer
Correct Answer is :
indexes
5. Pipeline stages can use __________ for tasks such as calculating the average or concatenating a string.
A. replicas
B. operators
C. roles
D. all of the mentioned
Show Correct Answer
Correct Answer is :
operators
6. Point out the wrong statement :
A. Some pipeline stages may generate new documents or filter out documents
B. $limit groups output documents by a specified operator
C. $group groups input documents by a specified identifier expression
D. None of the mentioned
Show Correct Answer
Correct Answer is :
$limit groups output documents by a specified operator
7. To handle large datasets, set _________ option to true to enable writing data to temporary files.
A. enableDiskUse
B. allowDiskUse
C. validateDiksUse
D. none of the mentioned
Show Correct Answer
Correct Answer is :
allowDiskUse
8. ________ deconstructs an array field from the input documents to output a document for each element.
A. $unwindelem
B. $unwind
C. $unwin
D. None of the mentioned
Show Correct Answer
Correct Answer is :
$unwin
9. Point out the wrong statement :
A. Boolean expressions evaluate their argument expressions as booleans and return a boolean as the result
B. In addition to the false boolean value, Boolean expression evaluates as false the following: null, 0, and undefined values
C. Set expressions performs set operation on arrays, treating arrays as sets
D. None of the mentioned
Show Correct Answer
Correct Answer is :
None of the mentioned
10. ________ applies an expression to each item in an array and returns an array with the applied results.
A. $map
B. $geo
C. $geoRear
D. None of the mentioned
Show Correct Answer
Correct Answer is :
$map
11. Which of the following accepts named parameters ?
A. $reduce
B. $letnum
C. $let
D. None of the mentioned
Show Correct Answer
Correct Answer is :
None of the mentioned
12. String expressions, with the exception of ________ only have a well-defined behavior for strings of ASCII characters.
A. $setcon
B. $concatenation
C. $concat
D. None of the mentioned
Show Correct Answer
Correct Answer is :
$concat
13. ___________ returns either the non-null result of the first expression.
A. $Null
B. $ifNull
C. $ElseNull
D. None of the mentioned
Show Correct Answer
Correct Answer is :
$ifNull
14. Which of the following returns the value that results from applying an expression to the last document ?
A. $end
B. $last
C. $max
D. All of the mentioned
Show Correct Answer
Correct Answer is :
$last
15. Which of the following stages cannot appear multiple times in a pipeline ?
A. $regex
B. $reg
C. $match
D. $out
Show Correct Answer
Correct Answer is :
$match
16. Point out the correct statement :
A. To access variables in expressions, use a string that prefixes the variable name with $$$
B. Expressions can include field paths and system variables, literals, expression objects, and expression operators
C. To specify a field path, use a string that prefixes with a dollar sign % the field name or the dotted field name
D. All of the mentioned
Show Correct Answer
Correct Answer is :
Expressions can include field paths and system variables, literals, expression objects, and expression operators
17. Aggregation expressions use ______ path to access fields in the input documents.
A. mpath
B. dbpath
C. lpath
D. field
Show Correct Answer
Correct Answer is :
field
18. Which of the following statement is equivalent to “$$CURRENT.“?
A. “$%”
B. “%”
C. “$$”
D. “$”
Show Correct Answer
Correct Answer is :
“$”
19. Point out the wrong statement:
A. Literals can be of any type
B. CURRENT cannot be rebound
C. MongoDB parses string literals that start with a dollar sign $
D. None of the mentioned
Show Correct Answer
Correct Answer is :
CURRENT cannot be rebound
20. ______ binds variables for use in the specified expression.
A. $skip
B. $let
C. $bind
D. None of the mentioned
Show Correct Answer
Correct Answer is :
$let
Similar Interview Questions
Search for latest jobs
Find Jobs