A data analyst needs to produce a report of the top 5 products by total sales for each region. The database has tables: Products (ProductID, ProductName), Regions (RegionID, RegionName), Sales (SaleID, ProductID, RegionID, Amount). They need to write a SQL query that returns the top 5 products per region. Which approach is correct?

Use a CROSS JOIN between Products and Regions and then filter by sales.

Use a subquery to find the maximum sales per region and then join back to get the product.

Use a window function with ROW_NUMBER() partitioned by RegionID and ordered by SUM(Amount) DESC, then filter for row numbers <= 5.

Use GROUP BY RegionID, ProductID with ORDER BY SUM(Amount) DESC LIMIT 5.

What is the purpose of setting a random seed when generating randomized data?

To ensure the data is normally distributed.

To increase the speed of generation.

To ensure reproducibility of the generated data.

What is the purpose of pagination in API responses?

To break large result sets into smaller, manageable pages.

To encrypt the data in the response.

To compress the data in the response.

CertNexusCertified Data Science Practitioner (CDSP)

Domain 2Objective 1

Objective 2.1 Gather Data Sets CERTIFIED-DATA-SCIENCE-PRACTITIONER Practice Questions (Page 6)

Part of the 2.0 Extracting, Transforming, and Loading Data domain, which accounts for 17-25% of the CERTIFIED-DATA-SCIENCE-PRACTITIONER exam.

39questions here

8free pages

15concepts

17-25%of the exam

15 Concepts in This Objective

Read Data from Various Sources
SQL Query Writing
NoSQL Query Writing
Cloud Storage Integration
First-, Second-, and Third-Party Data Sources
Data Collection Methods
Data Sharing Agreements
Exploring Third-Party Data Availability
Collecting Open-Source Data
Using APIs for Data Collection
Web Scraping
Generating Dummy or Test Data
Generating Randomized Data
Generating Anonymized Data
Generating AI-Generated Synthetic Data

Questions 26–30

26expert · hard
A data analyst needs to produce a report of the top 5 products by total sales for each region. The database has tables: Products (ProductID, ProductName), Regions (RegionID, RegionName), Sales (SaleID, ProductID, RegionID, Amount). They need to write a SQL query that returns the top 5 products per region. Which approach is correct?
Select an answer first
27foundation · easy
Which data collection method is most appropriate for gathering customer satisfaction feedback from a large, geographically dispersed population?
Select an answer first
28foundation · easy
What is the purpose of setting a random seed when generating randomized data?
Select an answer first
29foundation · easy
Which data collection method is most appropriate for capturing real-time temperature readings from a manufacturing process?
Select an answer first
30foundation · easy
What is the purpose of pagination in API responses?
Select an answer first

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Objective 2.1 Gather Data Sets CERTIFIED-DATA-SCIENCE-PRACTITIONER Practice Questions (Page 6)

Questions 26–30

Which data collection method is most appropriate for gathering customer satisfaction feedback from a large, geographically dispersed population?

What is the purpose of setting a random seed when generating randomized data?

Which data collection method is most appropriate for capturing real-time temperature readings from a manufacturing process?

What is the purpose of pagination in API responses?

Keep studying — 2.0 Extracting, Transforming, and Loading Data