Free C100DEV Mock Exam – Practice Online Confidently

Which of the following stages do you need to use to randomly select 10 documents from a specific collection?

You are developing a MongoDB application where write performance is a critical requirement. Given a scenario where your application primarily performs insert operations and rarely performs updates or deletes, which of the following MongoDB features would best optimize this heavy-write workload?

Consider a MongoDB collection named orders which has documents in the following format:{    "_id" : ObjectId("5f5b0d2f3e3dfbcc11c84444"),    "orderId" : 1001,    "customerId" : 200,    "items" : [        {            "productId" : 101,            "quantity" : 2        },        {            "productId" : 102,            "quantity" : 1        }    ],    "totalAmount" : 250,    "status" : "Pending"}What is the correct syntax to find and update the first document in the orders collection where "status" is "Pending", and change the "status" field to "Completed" using the findAndModify method?

Consider the following scenario: You have a MongoDB collection named users that stores user information. Each document in the collection has the following structure:{  "_id": ObjectId("609fe4b5728ad805aef1a88d"),  "name": "John Doe",  "age": 30,  "email": "[email protected]",  "address": {    "street": "123 Main St",    "city": "New York",    "state": "NY",    "zipcode": "10001"  }}You need to retrieve all the documents from the users collection and convert them to an array format. Which of the following MongoDB queries should you use for this task?

Consider a MongoDB database containing a collection of documents representing product information for an e-commerce website. The documents have the following structure:{   "_id": ObjectId("5f95a1d11a12b400001b75c0"),   "product_name": "Smartphone",   "brand": "Apple",   "price": 800,   "categories": [ "Electronics", "Smartphones" ],   "reviews": [      { "username": "user1", "rating": 4, "comment": "Great product!" },      { "username": "user2", "rating": 5, "comment": "Excellent!" },      { "username": "user3", "rating": 3, "comment": "Good but overpriced." }   ]}Select the MongoDB aggregation pipeline that returns the average rating of all products grouped by brand. The result should include only brands with an average rating greater than or equal to 4. The output should have the following format: