Why doesn't mongo produce $unwind of arrays on an array?

Question

MongoDB

Document example:

{
myArray: [
    {
        nestedArray: ["a", "b", "c"]
    }
]
}

I make a request like this:

db.collection.aggregate([$unwind: "$myArray.nestedArray"]) // выдаёт пустой ответ
db.collection.aggregate([$unwind: "$myArray"]) // выдаёт нормально

It is required to make $unwind on a nested array, and on an external one. So that the number of rows is myArray.length * nestedArray.length

Answer 1

Try twice to make $unwind. First "$myArray", second $myArray.nestedArray"