Which features of relational database management systems were deliberately omitted in MongoDB and help us to obtain horizontal scalability? Check all that apply.
We can insert multiple documents in bulk using which of the following operations:
Consider that the posts collection contains an array called ratings which contains ratings given to the post by various users in the following format:
Which of the following query will return all the documents where the ratings array contains elements that in some combination satisfy the query conditions?
In order to ensure that you can maintain high availability in the face of server failure, you should implement which of the following?
As per the aggregation pipeline optimization concepts, if you have a $sort followed by a $match:
What is the replication factor for a replicated cluster with 1 primary, 3 secondaries with one of them hidden. The set also has an arbiter?
Which of the following commands will return all the posts with number of likes greater than 100 and less than 200, both inclusive?
What is the equivalent command in MongoDB for the following SQL query?
SELECT * FROM posts WHERE author like "%john%"
In a sharded replicas set environment with multiple mongos servers, which of the following would decide the mongos failover?
Which mongodb tool is used to report details on number of database operations in MongoDB?
In a collection that contains 100 post documents, what does the following command do? db. posts. find().skip(5).limit(5)
Given a collection posts as shown below having a document array comments, which of the following command will create an index on the comment author descending?
In a replica set, a_________number of members ensures that the replica set is always able to select a primary.
The oplog (operations log) is a special capped collection that keeps a rolling record of all operations that modify the data stored in your databases. All the replica set members contain a copy of the oplog in the following collection:
What does the following $slice query return using the following command? db.posts.find( {}, { comments: { $slice: [ -10, 5 ] } } )
Dada una coleccion, cuales devuelve con la siguiente query db.coleccion.find({nombre:"ruben",apellido:"gomez"},{nombre:l,apellido:l,aficion:l});
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?
Given a replica set with five data-bearing members, suppose the primary goes down with operations in its oplog that have been copied from the primary to only one secondary. Assuming no other problems occur, which of the following describes what is most likely to happen?
Which of the following command inside aggregate command is used in MongoDB aggregation to filter the documents to pass only the documents that match the specified condition(s) to the next pipeline stage.
You are in a sharded cluster. What will you do prior to initiating backup in sharded cluster?
Which of the following is incorrect statement about find and findOne operations in MongoDB?
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.
Which of the following aggregate commands in MongoDB uses a pipeline approach with the goals of improving the aggregation performance?
Which of the following is true of the mechanics of replication in MongoDB? Check all that apply.
Consider the following example document from the sample collection. All documents in this collection have the same schema.
Which of the following queries will replace this with the document.