C100DBA 試験問題を無料オンラインアクセス

You have the following index on the toys collection:
{
"manufacturer" : 1,
"name" : 1,
"date" : -1
}
Which of the following is able to use the index for the query? Check all that apply.

• A.db.toys.find( { date : "2015-03-01", manufacturer : "Loggo", name : "Brick Set" } )
• B.db.toys.find( { manufacturer : "Matteo", name : "Barbara", date : "2014-07-02" } )
• C.db.toys.find( { name : "Big Rig Truck", date : "2013-02-01", manufacturer : "Tanko"

Which features of relational database management systems were deliberately omitted in MongoDB and help us to obtain horizontal scalability? Check all that apply.

• A.Authentication
• B.Multi-statement transactions
• C.Joins

The following aggregation option is used to specify the specific fields that needs to be passed to the next stage of the aggregation pipeline:

• A.$match
• B.$aggregate
• C.$project
• D.$group

Consider that you have a collection called population which has fields state and city. Which of the following query will calculate the population grouped by state and city?

• A.db.population.aggregate( [{ $group: { _id: { state: Estate", city: "$city" },pop: { $sum: 1 > > >] )
• B.db.population.aggregate( [{ $group: { _id: { city: "$city" },pop: { $sum: "$pop" } } }] )Multi Document Transaction is not supported by MongoDB
• C.db.population.aggregate( [{ $group: { _id: { state: "$state", city: "$city" },pop: { $pop: 1 } } }] )
• D.db.population.aggregate( [{ $group: { _id: { state: Estate", city: "$city" },pop: { $sum: "$pop" } } }] )

In mongodb how do you update a document partially?

• A.$update
• B.$modify
• C.$project
• D.$set