DA0-002 Data Concepts and Environments Practice Question
A company uses a NoSQL document database to store product catalogs. Each product document includes fields like product_id, name, category, and price. The operations team frequently queries by product_id and by category. Which type of NoSQL database is being used, and what should be created to optimize queries by category?
⚠ Common exam trap
CompTIA Data+ may test the misconception that all NoSQL databases support secondary indexes similarly. The trap here is that document databases natively support secondary indexes, while key-value and wide-column stores require different optimization strategies.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Document database; create an index on category
The question explicitly states a document database is used, and the operations team frequently queries by category. In a document database like MongoDB, creating an index on the category field optimizes these queries by allowing the database to quickly locate documents without scanning every document in the collection. This is the standard approach for improving query performance on non-primary-key fields in document stores.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Key-value store; create a secondary index on category
Why it's wrong here
Key-value stores typically index only by key; secondary indexes are not common.
- ✗
Graph database; create a relationship between products
Why it's wrong here
Graph databases are for connected data, not document storage.
- ✓
Document database; create an index on category
Why this is correct
Document databases support secondary indexes on any field, which speeds up queries.
- ✗
Wide-column store; create a column family for category
Why it's wrong here
Wide-column stores are different from document databases; the scenario describes documents.
Go deeper
Related to this question
About these practice questions
Courseiva writes every DA0-002 question from scratch — 986 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This DA0-002 practice question is part of Courseiva's free CompTIA certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the DA0-002 exam.