DEA-C01 Practice Test 12 — 15 Questions

Question 1

Refer to the exhibit. An S3 event notification is configured to trigger an AWS Lambda function when objects are created in 'my-bucket'. The Lambda function processes the JSON file and writes results to Amazon DynamoDB. The function fails with a timeout error. Which action should the engineer take to resolve the issue?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

Increase the Lambda function timeout. The Lambda function is failing with a timeout error, which indicates that the function is taking longer to execute than the default timeout of 3 seconds. Increasing the Lambda function timeout allows the function to run longer and complete its processing of the JSON file and DynamoDB write operation without being prematurely terminated.

Answer

Modify the S3 event notification to use a different event type

Answer

Grant the Lambda function permission to access DynamoDB

Answer

Change the trigger to Amazon SQS instead of S3

Question 2

A data engineer runs the above command and gets the output. What does the 'MFADelete' setting imply?

Accepted Answer

To permanently delete a version of an object, the user must provide MFA.. The 'MFADelete' setting on an S3 bucket versioning configuration requires multi-factor authentication to permanently delete an object version. This means that when a user issues a DELETE request with a version ID (a permanent delete), they must include a valid MFA token in the request headers. It does not apply to creating new versions, reading objects, or other operations.

Answer

Any modification to an object requires MFA.

Answer

MFA is required for all read operations as well.

Answer

All operations on the bucket require MFA authentication.

Question 3

A data engineer is optimizing an Amazon RDS for MySQL database that experiences high write throughput. The engineer wants to improve write performance and reduce latency. Which TWO database-level configuration changes can help achieve this?

Accepted Answer

Use Provisioned IOPS (io1 or io2) storage.. Provisioned IOPS (io1 or io2) storage delivers consistent and predictable I/O performance by guaranteeing a specified number of I/O operations per second, which directly reduces latency and improves write throughput for high-write workloads. This is the most effective storage-level change for write-intensive RDS for MySQL databases.

Answer

Reduce the backup retention period to 1 day.

Answer

Create a Read Replica to offload writes.

Answer

Enable Multi-AZ for high availability.

Question 4

A data engineer needs to audit data access in Amazon S3 for compliance. Which TWO services can be used to capture and analyze S3 access logs? (Choose TWO.)

Accepted Answer

AWS CloudTrail. AWS CloudTrail (B) is correct because it records S3 data events (object-level operations like GetObject and PutObject) and management events, delivering them to CloudTrail logs or CloudWatch Logs for auditing and analysis of who accessed what in S3. S3 server access logs (C) are correct because they provide detailed, best-effort records of every request made to a bucket, including requester, bucket, key, operation, and response codes, which can be stored and analyzed for compliance auditing. Amazon CloudWatch Logs (A) is not a log source for S3 access itself; it only stores and analyzes logs that are delivered to it by other services such as CloudTrail. Amazon Macie (D) is a data security service that discovers and classifies sensitive data in S3, not a service for capturing S3 access logs. AWS Config (E) tracks resource configuration changes and compliance against rules, not individual S3 data access events.

Answer

Amazon CloudWatch Logs

Answer

Amazon Macie

Answer

AWS Config

Question 5

A data engineer needs to monitor the performance of an Amazon Redshift cluster. Which Amazon CloudWatch metric should the engineer monitor to detect disk space issues?

Accepted Answer

PercentageDiskSpace. PercentageDiskSpace is the correct metric because it directly reports the percentage of disk space used in the Redshift cluster. Monitoring this metric allows the engineer to detect when disk space is running low, which can lead to performance degradation or query failures. Unlike I/O or CPU metrics, it specifically measures storage utilization, making it the most relevant for disk space issues.

Answer

ReadIOPS

Answer

WriteIOPS

Answer

NetworkThroughput

Answer

CPUUtilization

Question 6

A data engineer needs to ingest data from a SaaS application (Salesforce) into Amazon S3 on a daily basis. Which TWO AWS services can be used for this purpose? (Choose TWO.)

Accepted Answer

AWS Glue. Amazon AppFlow (option E) is purpose-built for ingesting data from SaaS applications like Salesforce into AWS destinations such as Amazon S3, supporting scheduled daily flows without custom code. AWS Glue (option D) can also perform this ingestion by using its Salesforce connector within Glue ETL jobs or Glue Studio, writing the extracted data to S3 on a schedule. AWS DataSync (A) is designed for migrating and syncing file data between on-premises storage and AWS, not for SaaS API ingestion. Amazon Kinesis Data Streams (B) is a real-time streaming service that requires custom producers and does not natively connect to Salesforce. AWS Transfer Family (C) only provides managed SFTP, FTPS, and FTP endpoints into S3 or EFS, which does not address SaaS application ingestion.

Answer

AWS DataSync

Answer

Amazon Kinesis Data Streams

Answer

AWS Transfer Family

Question 7

A data engineer is troubleshooting an Amazon Redshift cluster that is not allowing connections from a specific IP range. The engineer verified that the cluster's security group allows inbound traffic from the IP range. What is the next step to resolve the issue?

Accepted Answer

Check the network ACL (NACL) associated with the Redshift cluster's subnet.. Even if the security group allows inbound traffic from a specific IP range, the network ACL (NACL) associated with the Redshift cluster's subnet can block traffic at the subnet level. NACLs are stateless and can override security group rules. Option A is incorrect because modifying the cluster parameter group does not control network-level access; public accessibility is a separate setting. Option B is incorrect because the engineer already verified the security group, but even if it is correctly attached, the NACL could still block traffic. Option C is incorrect because IAM roles control authentication and authorization, not network connectivity.

Answer

Modify the Redshift cluster parameter group to enable public accessibility.

Answer

Verify that the cluster's security group is attached to the Redshift cluster.

Answer

Check the IAM role associated with the Redshift cluster.

Question 8

Refer to the exhibit. A data engineer runs a Glue job manually and receives a ThrottlingException. The engineer checks the job run history and sees a previous failure with the same error. What is the MOST likely cause of the throttling, and which solution is MOST appropriate?

Accepted Answer

Implement retry logic with exponential backoff in the script that calls start-job-run.. A ThrottlingException from AWS Glue typically occurs when the StartJobRun API is called too frequently, exceeding the service's request rate limits. Implementing retry logic with exponential backoff in the calling script is the standard AWS-recommended solution to handle transient throttling gracefully. This allows the job to start successfully after a short delay without manual intervention.

Answer

Increase the number of DPUs for the job to reduce runtime.

Answer

Use AWS Glue reserved capacity to guarantee API throughput.

Answer

Delete old job runs to reduce the number of entries in the job run history.

Question 9

A company uses AWS Kinesis Data Streams to ingest real-time data. The data engineer notices that the stream's 'WriteProvisionedThroughputExceeded' error occurs frequently during peaks. Which action should be taken to resolve this issue?

Accepted Answer

Increase the number of shards in the stream.. The 'WriteProvisionedThroughputExceeded' error occurs when the stream's write capacity is exceeded. Increasing the number of shards (A) increases the stream's write capacity, as each shard provides a fixed write throughput (1 MB/s or 1000 records/s). This directly resolves the issue by adding more capacity to handle peak loads.

Answer

Modify the producer to use a different partition key.

Answer

Compress the data before sending to the stream.

Answer

Enable enhanced fan-out for consumers.

Question 10

A company has a large volume of CSV files in S3 that need to be transformed into Parquet using AWS Glue. The files are partitioned by date. The engineer wants to minimize costs by processing only new files each day. Which approach should be used?

Accepted Answer

Enable job bookmarks in the Glue job.. AWS Glue job bookmarks track the state of data processed by a job, so subsequent runs only process new or changed data. When enabled, bookmarks persist the last processed path or partition, allowing the daily job to skip already-transformed files and reduce runtime and cost. This directly satisfies the requirement to process only new files each day.

Answer

Use S3 partition discovery to automatically read new partitions.

Answer

Schedule the Glue job to run daily and process all files.

Answer

Use S3 Event Notifications to trigger the Glue job on each new file.

Question 11

A data pipeline uses Amazon Kinesis Data Firehose to deliver data to an Amazon S3 bucket. The delivery stream is configured with a buffer size of 5 MB and a buffer interval of 60 seconds. The team notices that the S3 objects are much smaller than 5 MB. What is the most likely explanation?

Accepted Answer

The incoming data volume is low, so the 60-second buffer interval triggers delivery before the 5 MB buffer is filled.. If the incoming data rate is low, the buffer interval (60 seconds) expires before the buffer size (5 MB) is reached, causing small objects. Option B is incorrect because S3 event notifications do not split objects; they are triggered by events but do not affect object size. Option C is incorrect because S3 lifecycle policies transition objects to Glacier, which does not affect object size during delivery. Option D is incorrect because GZIP compression reduces the object size after batching, but the buffer interval can still trigger delivery before the buffer is full, so it is not the most likely explanation.

Answer

The S3 bucket has event notifications that split the objects.

Answer

The S3 bucket has a lifecycle policy that transitions objects to Glacier.

Answer

The delivery stream is using GZIP compression, which reduces the object size.

Question 12

A company has a nightly batch job that processes 100 GB of data from an Amazon S3 bucket and loads it into an Amazon Redshift table. The job currently runs on an Amazon EMR cluster. Which service would reduce operational overhead while providing similar functionality?

Accepted Answer

AWS Glue. AWS Glue is a serverless ETL service that can process 100 GB of data from S3 and load it into Redshift without managing any infrastructure. It provides built-in job scheduling, automatic retries, and a Spark-based engine that handles large-scale data transformations, directly replacing the EMR cluster's functionality while eliminating operational overhead.

Answer

AWS Database Migration Service

Answer

Amazon Redshift Spectrum

Answer

Amazon Athena

Question 13

A company needs to ingest data from a MySQL database into Amazon S3 using AWS DMS. The data changes frequently and the requirement is to capture changes in near real-time. Which THREE configurations are necessary?

Accepted Answer

Create an S3 target endpoint in DMS.. Option B is correct because AWS DMS requires an explicitly defined target endpoint that describes the S3 bucket, folder, and IAM role used to write the migrated data. Option C is correct because ongoing change data capture (CDC) from MySQL relies on the source's binary log (binlog), which must be enabled with settings such as log_bin and binlog_format=ROW so DMS can read committed changes in near real-time. Option D is correct because a replication instance is the managed compute resource that runs the DMS migration and CDC tasks between the source and target endpoints. Option A is not required, since a VPC endpoint for S3 is only an optional networking choice and not a mandatory DMS configuration. Option E is not required, because DMS tasks are started and monitored by DMS itself, not by S3 event notifications.

Answer

Create a VPC endpoint for S3.

Answer

Configure an S3 event notification to trigger DMS.

Question 14

A data engineer needs to ingest data from an Amazon S3 bucket into Amazon Redshift for analytics. The data is in CSV format and the Redshift table already exists. Which service can be used to perform this ingestion with minimal configuration?

Accepted Answer

Amazon Redshift COPY command. The Amazon Redshift COPY command is the most direct and minimal-configuration method to load data from an S3 bucket into an existing Redshift table. It is purpose-built for bulk data ingestion from S3, supports CSV format natively, and requires only the table name, S3 path, IAM role, and format options — no additional services or pipelines needed.

Answer

AWS Glue

Answer

Amazon Kinesis Data Firehose

Answer

AWS Database Migration Service (DMS)

Question 15

A company wants to ingest streaming data from thousands of IoT devices into AWS for real-time analytics. Which AWS service is best suited for this purpose?

Accepted Answer

Amazon Kinesis Data Streams. Amazon Kinesis Data Streams is purpose-built for ingesting and processing streaming data at scale from thousands of sources. It can capture and store terabytes of data per hour from IoT devices, enabling real-time analytics with millisecond latencies. The service provides durable, ordered data streams that can be consumed by multiple applications simultaneously.

Answer

Amazon S3

Answer

AWS Lambda

Answer

Amazon RDS