Question

In the $unwind stage, each output document is the ___ with the value of the ___ field replaced by the ___.

Answer 1

In the $unwind stage of a MongoDB aggregation pipeline, an output document is the same with the specified array field replaced by each of its individual elements.

Step-by-step explanation:

In the $unwind stage of a MongoDB aggregation pipeline, each output document is the same as the input document with the value of the specified array field replaced by an individual element from the array. If an input document's specified array field is an array, the $unwind stage produces a new document for each element of the array. If the specified field is not an array, the $unwind stage will produce a single output document with the field as is.