A. Calculates the number of posts with likes between 100 and 200
B. Fetches the posts with likes between 100 and 200 and sets their _id as null
C. Fetches the posts with likes between 100 and 200, sets the _id of the first document as null and then increments it 1 every time
D. Groups the posts by number of likes (101, 102, 103.) by adding 1 every time
A. You should use it early as possible in the pipeline
B. It can be used as many time as needed.
C. It has a sintax similar to findQ commands.
A. Providing these parameters in any order does not impact the performance
B. $sort moves before $match
C. $match moves before $sort
D. MongoDB does not do any movements by default and will use the order provided
A. MongoDB uses JSON format to represent documents
B. MongoDB supports some of the SQL functions
C. MongoDB supports collection joins
D. MongoDB supports geospatial indexes
A. $project
B. $match
C. $aggregate
D. $group
A. It will insert two documents and throw a warning to the user
B. Two documents will be inserted with _id as 1
C. This will throw a duplicate key error
D. MongoDB will automatically increment the _id of the second document as 2
A. Null, Number, Object and String
B. String, Null, Number and Object
C. Null, Number, String and Object
D. Number, Null, String and Object
A. ACID Transactions
B. Journaling
C. Relationships between Collections (Primary Key Foreign Key)
D. Transaction Management
A. aggregate
B. mapReduce
C. All of the above
D. group
A. db.posts.createIndex({^commerits.author";-!});
B. db.posts.createIndex({^comments.$.author":-l});
C. db. posts.createIndex({^comments.author" :1});
