Data Engineer - Associate Practice Questions
Prepare for DEA-C01 with more than an answer.
Unlock the full exam and previous versions
- v1Version 1 270 questions Current
- DAS-C01Legacy AWS Certified Data Analytics - Specialty 85 questions Locked
- Exam fee
- $150 USD
- Level
- Associate
- Valid for
- 3 years
Domains covered on the exam 4
- Data Ingestion and Transformation34%
- Data Store Management26%
- Data Operations and Support22%
- Data Security and Governance18%
- 1
A multinational retail company stores historical sales data in Amazon S3. The data is partitioned by
countryandyear. A data analyst running Amazon Athena queries notices that queries filtering for a specific country and year are scanning significantly more data than expected, resulting in high costs and slow performance. Upon investigation, the data engineer finds that the S3 objects are not physically organized into folders matching the partition keys. What must the data engineer do to fix this issue?Show answer details
Correct answer: C
For Athena to effectively prune partitions and reduce data scanned, the data in S3 must be physically organized into a directory structure that matches the partition keys (Hive-style partitioning). Once restructured, the catalog needs to be updated (via MSCK REPAIR TABLE or Glue Crawler) to recognize these paths.
- 2
A financial organization requires that all sensitive data stored in Amazon Redshift be encrypted at rest using a customer-managed key (CMK). They also need to ensure that the key is automatically rotated every year. Which configuration meets these requirements?
Show answer details
Correct answer: B
Using a Customer Managed Key (CMK) allows the customer to control the key policy. Enabling automatic key rotation for a CMK rotates the key material every year (365 days), meeting the specific requirements.
- 3
A data engineer is troubleshooting an AWS Glue Spark ETL job that is failing with an
OOM (Out Of Memory)error. The job processes a large dataset with a skewed distribution of keys during a join operation. Which strategy is MOST likely to resolve the memory issue?Show answer details
Correct answer: D
Data skew causes one executor to process significantly more data than others, leading to OOM. Enabling AQE (available in Glue 3.0+) can automatically handle skew join optimization. Alternatively, manually 'salting' the keys (adding a random suffix) distributes the skewed data across multiple partitions, relieving memory pressure.
- 4
A company uses AWS Step Functions to orchestrate a data pipeline. One state involves an AWS Lambda function that triggers an asynchronous long-running process in an external third-party API. The workflow must wait for the external process to complete before moving to the next state. The external API can send a webhook callback upon completion. Which integration pattern should the data engineer use?
Show answer details
Correct answer: C
The
.waitForTaskTokenpattern allows Step Functions to pause a workflow indefinitely until a task token is returned via theSendTaskSuccessAPI call. The Lambda can pass this token to the external API, which can then call back with the token upon completion. - 5
True or False: In AWS Lake Formation, if you grant a user the
SELECTpermission on a table but explicitly denySELECTpermission on a specific column within that table, the user will be able to query the table but will seeNULLvalues for the restricted column.Show answer details
Correct answer: B
False. In Lake Formation, if a user is restricted from accessing a specific column (via column-level security), they cannot query that column at all. If they attempt to include that column in a
SELECT *or specificSELECT columnquery, the query will fail with an authorization error. It does not mask the data with NULLs; it prevents access to the column definition entirely. - 6
A data engineer is configuring an AWS Glue job to read data from an Amazon S3 bucket. The data engineer has set up the necessary AWS Glue connection details and an associated IAM role. However, when the data engineer attempts to run the AWS Glue job, the data engineer receives an error message that indicates that there are problems with the Amazon S3 VPC gateway endpoint.The data engineer must resolve the error and connect the AWS Glue job to the S3 bucket.Which solution will meet this requirement?
Show answer details
Correct answer: D
- 7
A retail company has a customer data hub in an Amazon S3 bucket. Employees from many countries use the data hub to support company-wide analytics. A governance team must ensure that the company's data analysts can access data only for customers who are within the same country as the analysts.Which solution will meet these requirements with the LEAST operational effort?
Show answer details
Correct answer: B
- 8
A media company wants to improve a system that recommends media content to customer based on user behavior and preferences. To improve the recommendation system, the company needs to incorporate insights from third-party datasets into the company's existing analytics platform.The company wants to minimize the effort and time required to incorporate third-party datasets.Which solution will meet these requirements with the LEAST operational overhead?
Show answer details
Correct answer: A
