Free MongoDB C100DEV Exam Questions

You manage a MongoDB collection called inventory that stores documents for a store's inventory. Each document has the fields item, category, and quantity. You want to ensure that an item is always present in the collection, even if it needs to be inserted. Specifically, if the item "notebook" in the "Stationery" category does not exist, it should be inserted with a quantity of 50. If it does exist, its quantity should be updated to 50. You plan to use the following command:

db.inventory.updateOne(

  { "item": "notebook", "category": "Stationery" },

  { $set: { "quantity": 50 } },

  { upsert: true }

)

What will happen after executing this command if there is no "notebook" item in the "Stationery" category in the inventory collection?

Given a movies collection where each document has the following structure:

{

    _id: ObjectId('573a1390f29313caabcd60e4'),

    genres: [ 'Short', 'Comedy', 'Drama' ],

    title: 'The Immigrant',

    year: 1917,

    imdb: { rating: 7.8, votes: 4680, id: 8133 },

    countries: [ 'USA' ]

}

Which of the following queries will find all the movies that have more votes than the year in which they were released?

Given the following orders collection in MongoDB:

[

  {

    "_id": 1,

    "customer": "John",

    "orderDetails": [

      { "productId": "P1", "quantity": 2, "unitPrice": 50 },

      { "productId": "P2", "quantity": 1, "unitPrice": 30 }

    ]

  },

  {

    "_id": 2,

    "customer": "Sara",

    "orderDetails": [

      { "productId": "P1", "quantity": 3, "unitPrice": 50 },

      { "productId": "P3", "quantity": 2, "unitPrice": 20 }

    ]

  },

  {

    "_id": 3,

    "customer": "Peter",

    "orderDetails": [

      { "productId": "P2", "quantity": 2, "unitPrice": 30 },

      { "productId": "P4", "quantity": 1, "unitPrice": 100 }

    ]

  }

]

Which MongoDB query will find all orders that contain a product with the productId of "P1" and a quantity greater than 1?