array field in mongodb code example

Example 1: how to get array object value in mongodb

db.products.aggregate([
    {$unwind: "$ratings"},
    {$match: {'ratings.user': ObjectId("5f6e2e0b70eb0208fc8401a1")}}
])

Example 2: find string element in an array mongodb

db.articles.find({
    "stock.country" : "01",
    "stock.warehouse.code" : "02"
}).pretty();