, WGU D492 Data Analytics – Applications | CompTIA
Data+ DA0-002 Certification Exam | Complete Study
Guide with 200+ Verified Questions & Answers |
2026/2027 Update | Graded A+
1.0 Data Concepts and Environments (20%)
Foundational structures, data systems, and how data is stored and accessed.
Q1. You are choosing a storage solution for transactional sales
data that must support frequent small writes and ACID
guarantees. Which environment is MOST appropriate?
A. Data lake built on object storage
B. Relational OLTP database
C. Static CSV files on shared drive
D. NoSQL key–value cache only
Answer: B
Rationale: OLTP relational databases are optimized for
transactional workloads, enforcing ACID properties for reliable
inserts and updates.
Q2. A dataset includes JSON logs from an API and structured
tables in a warehouse. This combination BEST illustrates
which concept?
A. Single structured data source
,B. Semi-structured and structured data sources
C. Unstructured multimedia only
D. Time-series data only
Answer: B
Rationale: Warehouse tables are structured, whereas JSON
logs are semi-structured data with labeled fields but flexible
schema.
2.0 Data Acquisition and Preparation (22%)
Collecting, cleaning, profiling, and transforming data for analysis.
Q3. While profiling data, you find many customer records with
missing phone numbers but complete email addresses. What
is the BEST first step?
A. Drop all rows with any missing value
B. Flag missing phone numbers as a data quality issue and
assess business impact
C. Replace all missing phones with zeros
D. Ignore the issue because email is present
Answer: B
Rationale: Profiling should highlight missing values and
evaluate whether they affect the analysis or require
remediation.
Q4. You need to combine an orders table with a customers
, table to see each customer’s latest order. Which join type is
MOST appropriate to keep all customers, even those with no
orders?
A. INNER JOIN
B. LEFT JOIN customers to orders
C. RIGHT JOIN orders to customers
D. CROSS JOIN
Answer: B
Rationale: A LEFT JOIN from customers to orders preserves
all customers and returns NULLs for customers with no orders.
4.0 Visualization (18%)
Designing effective charts, dashboards, and data stories.
Q5. An analyst wants to summarize monthly revenue by
region. Which visualization is MOST effective?
A. Pie chart with one slice per month
B. Line chart showing revenue trend over time for each region
C. Word cloud of region names
D. Scatter plot of customer IDs
Answer: B
Rationale: Line charts are ideal for showing trends over time,
and separate series can represent each region.
Data+ DA0-002 Certification Exam | Complete Study
Guide with 200+ Verified Questions & Answers |
2026/2027 Update | Graded A+
1.0 Data Concepts and Environments (20%)
Foundational structures, data systems, and how data is stored and accessed.
Q1. You are choosing a storage solution for transactional sales
data that must support frequent small writes and ACID
guarantees. Which environment is MOST appropriate?
A. Data lake built on object storage
B. Relational OLTP database
C. Static CSV files on shared drive
D. NoSQL key–value cache only
Answer: B
Rationale: OLTP relational databases are optimized for
transactional workloads, enforcing ACID properties for reliable
inserts and updates.
Q2. A dataset includes JSON logs from an API and structured
tables in a warehouse. This combination BEST illustrates
which concept?
A. Single structured data source
,B. Semi-structured and structured data sources
C. Unstructured multimedia only
D. Time-series data only
Answer: B
Rationale: Warehouse tables are structured, whereas JSON
logs are semi-structured data with labeled fields but flexible
schema.
2.0 Data Acquisition and Preparation (22%)
Collecting, cleaning, profiling, and transforming data for analysis.
Q3. While profiling data, you find many customer records with
missing phone numbers but complete email addresses. What
is the BEST first step?
A. Drop all rows with any missing value
B. Flag missing phone numbers as a data quality issue and
assess business impact
C. Replace all missing phones with zeros
D. Ignore the issue because email is present
Answer: B
Rationale: Profiling should highlight missing values and
evaluate whether they affect the analysis or require
remediation.
Q4. You need to combine an orders table with a customers
, table to see each customer’s latest order. Which join type is
MOST appropriate to keep all customers, even those with no
orders?
A. INNER JOIN
B. LEFT JOIN customers to orders
C. RIGHT JOIN orders to customers
D. CROSS JOIN
Answer: B
Rationale: A LEFT JOIN from customers to orders preserves
all customers and returns NULLs for customers with no orders.
4.0 Visualization (18%)
Designing effective charts, dashboards, and data stories.
Q5. An analyst wants to summarize monthly revenue by
region. Which visualization is MOST effective?
A. Pie chart with one slice per month
B. Line chart showing revenue trend over time for each region
C. Word cloud of region names
D. Scatter plot of customer IDs
Answer: B
Rationale: Line charts are ideal for showing trends over time,
and separate series can represent each region.
