M101N: MONGODB FOR .NET DEVELOPERS questions 4.1

HOMEWORK: HOMEWORK 4.1

Suppose you have a collection with the following indexes:

> db.products.getIndexes()
[
 {
  "v" : 1,
  "key" : {
   "_id" : 1
  },
  "ns" : "store.products",
  "name" : "_id_"
 },
 {
  "v" : 1,
  "key" : {
   "sku" : 1
  },
                "unique" : true,
  "ns" : "store.products",
  "name" : "sku_1"
 },
 {
  "v" : 1,
  "key" : {
   "price" : -1
  },
  "ns" : "store.products",
  "name" : "price_-1"
 },
 {
  "v" : 1,
  "key" : {
   "description" : 1
  },
  "ns" : "store.products",
  "name" : "description_1"
 },
 {
  "v" : 1,
  "key" : {
   "category" : 1,
   "brand" : 1
  },
  "ns" : "store.products",
  "name" : "category_1_brand_1"
 },
 {
  "v" : 1,
  "key" : {
   "reviews.author" : 1
  },
  "ns" : "store.products",
  "name" : "reviews.author_1"
 }

Which of the following queries can utilize an index to find all matching documents or to sort? Check all that apply.

db.products.find({'brand':"GE"})db.products.find({$and:[{price:{$gt:30}},{price:{$lt:50}}]}).sort({brand:1})db.products.find({brand:'GE'}).sort({category:1, brand:-1}).explain()db.products.find({'brand':"GE"}).sort({price:1})