Task 3.2: Analyze Data by Using AWS Services DEA-C01 Practice Questions (Page 1)

Questions 1–5

1. 1foundation · easy

   A data engineer needs to calculate the total revenue from a sales table. Which SQL aggregate function should be used to sum all values in the 'revenue' column?

   • ACOUNT(revenue)
   • BAVG(revenue)
   • CMAX(revenue)
   • DSUM(revenue)
   Reveal Solution Discussion Select an answer first
2. 2foundation · easy

   A data engineer needs to compare quarterly sales across different regions. The current data has one row per region per quarter. The engineer wants a table where each region is a row and each quarter is a column, with sales as values. Which operation should be applied?

   • ASort the data by sales
   • BGroup the data by region
   • CPivot the data
   • DFilter the data by quarter
   Reveal Solution Discussion Select an answer first
4. 3foundation · easy

   A data engineer wants to visually explore and understand data patterns before writing transformation logic. The engineer needs a visual interface to profile data, identify anomalies, and create charts without writing code. Which AWS service provides these capabilities?

   • AAWS Glue DataBrew
   • BAmazon EMR
   • CAWS Step Functions
   • DAmazon Redshift
   Reveal Solution Discussion Select an answer first
5. 4application · medium

   A data engineer needs to analyze sales data in an Amazon Redshift cluster. The table 'sales' has columns: 'product_category', 'sales_month', and 'revenue'. The engineer needs to produce a report that shows each product category as a column and the total revenue for each month as rows. Which SQL feature should the engineer use to transform the data from rows to columns?

   • AUse GROUP BY product_category with a CASE statement for each month
   • BUse the UNPIVOT function with revenue FOR sales_month IN ('2024-01', '2024-02')
   • CUse the PIVOT function with SUM(revenue) FOR product_category IN ('Electronics', 'Clothing', 'Books')
   • DUse a self-join on the sales table to create the cross-tabulation
   Reveal Solution Discussion Select an answer first
6. 5expert · hard

   A company has an unpredictable analytics workload. The workload consists of occasional, complex queries that can run for several minutes, followed by long periods of inactivity. The company wants to minimize costs and does not want to manage any infrastructure. The data is stored in Amazon S3. Which service should the company use for this workload?

   • AAmazon Athena, because it is serverless and charges only for the queries that are run, making it cost-effective for unpredictable workloads.
   • BAmazon EMR, because it is serverless and can run Spark jobs on demand.
   • CAmazon Redshift, because it provides the best performance for complex queries and can be paused during inactivity.
   • DAmazon QuickSight, because it is serverless and can run queries against S3 data.
   Reveal Solution Discussion Select an answer first