$inc operator
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With the movie "The Martian":

    * increment "tomato.meter" with 2
    * increment "tomato.reviews" with 10

    db.movieDetails.updateOne({title: "The Martian"}, {$inc: {"tomato.meter": 2, "tomato.reviews": 10}})


What happens, if you increment a non-existing field?

    * increment "counter" with 2


Now decrement "counter" with 10, thus the new value should be -8.


When ready, delete the field "counter".