Question 1

When modeling a content management system in MongoDB, which approach best describes the handling of articles and their corresponding comments to optimize for frequent reads and occasional writes?

Options :

A : Articles and comments should be stored in separate collections, with comments embedding the full article document for efficiency.

B : Each comment should be stored in its own collection with a reference to its parent article ID.

C : Store each article in its own document within a single collection, with comments embedded as an array of subdocuments within each article.

D : A relational database management system must be used, as MongoDB cannot efficiently manage hierarchical data like articles and comments.

Answer: C

Question 2

In MongoDB schema design, what is a critical implication to consider when adding another piece of data into an array field, especially in the context of document size limitations and performance?

Options :

A : Arrays do not impact document size, allowing for unlimited data addition without performance concerns.

B : Adding elements to an array increases the risk of exceeding the BSON document size limit, potentially leading to failed updates.

C : Adding data to arrays significantly improves query performance by utilizing array-specific indexes.

D : Each addition to an array requires a complete document rewrite, which has no impact on performance or storage.

Answer: B

Question 3

A mobile application tracks user activities, interactions, and engagement metrics to offer personalized content and recommendations. To optimize the application's performance, particularly for generating monthly engagement reports and user insights, a data modeler is tasked with designing an efficient data storage strategy. What approach should the data modeler adopt to best meet these requirements?

Options :

A : Maintain separate collections for users, activities, and interactions, calculating engagement metrics and insights in real time upon each query.

B : Use a single collection for activities and employ on-the-fly aggregation queries for generating user engagement reports and insights whenever needed.

C : Store all user data, including activities and interactions, as embedded documents within a single user document in a single collection.

D : Utilize separate collections for Users, Activities, and EngagementMetrics. Use the computed pattern to periodically update EngagementMetrics with aggregated data.

Answer: D

Question 4

To improve the performance of queries on a logEntries collection, a MongoDB developer needs to find and analyze slow queries that have been executed. Which command should be used to identify and provide details on slow operations for analysis?

Options :

A : db.adminCommand({ "getLog": "global" })

B : db.setProfilingLevel(2, { "slowms": 100 })

C : db.logEntries.find({ "slowQuery": { $exists: true } })

D : db.logEntries.aggregate([ { $currentOp: { "slowOp": true } } ])

Answer: A

Question 5

A MongoDB data modeler needs to optimize a collection named orders to efficiently query documents based on the status field, which can have values like 'pending', 'completed', and 'canceled'. The collection has millions of documents, and the queries should return results quickly even under heavy load. Which of the following approaches best achieves this requirement while maintaining the collection's scalability and performance?

Options :

A : Create a separate collection for each status value and distribute the documents accordingly, querying the relevant collection based on the status.

B : Index the status field using a single field index, ensuring queries filtering by 'status' are more efficient.

C : Convert the status field into an array and use a multi-key index, ensuring multiple status values can be queried simultaneously.

D : Use a hashed index on the status field to evenly distribute the documents across the collection.

Answer: B

Higher Test Marks with Free Online Associate-Data-Modeler Exam Practice

Buying Options: