Explanation:$first returns the value that results from applying an expression to the first document in a group of documents that share the same group by key. 6. Which of the following returns the value that results from applying an expression to the last document ?
A. $end
B. $last
C. $max
D. All of the mentioned
Answer:A
Explanation:$first returns the value that results from applying an expression to the first document in a group of documents that share the same group by key. 6. Which of the following returns the value that results from applying an expression to the last document ?
A. $end B. $last C. $max D. All of the mentioned
Explanation:$last has the following syntax: { $last: }. 7. __________ returns the highest value from the group of values in documents.