Question

For all questions, provide appropriate MongoDB statements.

Question 1 (1 point) Create a collection called ‘games’. We’re going to put some games in it.

Question 2. (2 points) Add 5 games to the database. Give each document the following properties: name, genre, rating (out of 100).

Question 6. (6 points) Update your two favourite games to have two achievements called ‘Game Master’ and ‘Speed Demon’, each under a single key.

Question 7. (2 points) Write a query that returns all the games that have both the ‘Game Maser’ and the ‘Speed Demon’ achievements.

Question 8. (3 points) Write a query that returns only games that have achievements. Not all of your games should have achievements, obviously.

The last 3 are the ones I'm confused by.

Answer 1

Question 1)

db.createCollection("games")

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Question 2)

db.games.insert([{"name":"name1","genre":"genre1","rating":"75"},
{"name":"name2","genre":"genre2","rating":"50"},
{"name":"name3","genre":"genre3","rating":"65"},
{"name":"name4","genre":"genre4","rating":"90"},
{"name":"name5","genre":"genre5","rating":"100"}])

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Question 6)

See that we have to use the object ids that re generated.

These ids change dynamically.

So use the id that is generated while executing the query.

db.games.update({"_id" : ObjectId("5dfb0de3ac1b220c65afffff")},{$set:{"achievements":["Game Master","Speed Demon"]}})
db.games.update({"_id" : ObjectId("5dfb0de3ac1b220c65affffe")},{$set:{"achievements":["Game Master","Speed Demon"]}})

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Question 7)

db.games.find({"achievements":["Game Master","Speed Demon"]})

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Question 8)

db.games.find({achievements:{$exists:true}})

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