Map-reduce uses custom __________ functions to perform the map and reduce operations.

Which of the following operation can be optionally used for map reduce ?

The aggregation pipeline can use ___________ to improve its performance during some of its stages.

______ returns true if the first value is less than the second.

$ne returns true if the values are not _______

$multiply __________ numbers to return the result.

_______ adds numbers to return the sum, or adds numbers and a date to return a new date.

_______ returns the remainder of the first number divided by the second.

String expressions, with the exception of ________ only have a well-defined behavior for strings of ASCII characters.

MongoDB supports the execution of JavaScript code for certain server-side operations like: