DEA-C01 Data Operations and Support Practice Test 15 — 15 Questions

Question 1

A data engineer sees the CloudWatch log entry in the exhibit for a Lambda function that processes data from an Amazon SQS queue. What is the MOST likely cause of the timeout?

Accepted Answer

The Lambda function's timeout is too short for the processing required.. Option B is correct because the log shows the function used only 64 MB of the allocated 128 MB memory, indicating that memory is not the issue. The function timed out after 30 seconds, and the duration is 30001.23 ms, which is just over the default timeout of 30 seconds. Therefore, increasing the timeout will resolve the issue. Option A is incorrect because memory usage is low. Option C is incorrect because the function is not hitting memory limits. Option D is incorrect because SQS visibility timeout does not affect Lambda execution timeout directly; the Lambda timeout is separate.

Answer

The Lambda function's reserved concurrency is set too low.

Answer

The Lambda function is running out of memory.

Answer

The SQS queue's visibility timeout is set too low.

Question 2

A data engineer needs to implement a data pipeline that ingests data from an on-premises database using AWS DMS and loads it into Amazon S3 in Parquet format. The data should be encrypted at rest in S3 using a customer-managed KMS key. Which combination of actions should the engineer take? (Choose the correct course of action.)

Accepted Answer

Configure the DMS task to write to S3 in Parquet format, and specify the KMS key ID in the S3 endpoint settings.. Option D is correct because AWS DMS can write directly to S3 in Parquet format, and you can specify a KMS key for server-side encryption. Option A is incorrect because DMS does not support writing to S3 in JSON format without conversion, and encryption is handled by DMS settings. Option B is incorrect because DMS can write Parquet directly without an intermediate EC2 instance. Option C is incorrect because KMS encryption is set at the DMS task level, not via a bucket policy.

Answer

Set up an EC2 instance to run a script that reads from the source and writes Parquet to S3 with KMS encryption.

Answer

Use DMS to write JSON to S3, then use an AWS Glue job to convert to Parquet and enable KMS encryption on the Glue job.

Answer

Configure the S3 bucket policy to require KMS encryption for all objects, and use DMS with default settings.

Question 3

A data engineer creates an Amazon DynamoDB table using the CloudFormation snippet in the exhibit. The application writes 200 items per second to the table. The engineer notices that many write requests are being throttled. What is the MOST likely reason?

Accepted Answer

The provisioned write capacity is too low for the application's write rate.. Option D is correct because the table is provisioned with only 5 write capacity units, which allows 5 writes per second (each write up to 1 KB). With 200 writes per second, the table is severely under-provisioned. Option A is incorrect because the key schema is fine for a primary key. Option B is incorrect because the attribute type is correct. Option C is incorrect because the table name is valid.

Answer

The table does not have a sort key, causing hot partitions.

Answer

The attribute type for OrderID should be numeric for better performance.

Answer

The table name 'Orders' conflicts with an existing table.

Question 4

A data engineer is troubleshooting an Amazon Redshift cluster that has experienced a node failure. The engineer needs to ensure that the cluster is highly available and can withstand a single node failure without downtime. Which TWO actions should the engineer take?

Accepted Answer

Enable automated snapshots with cross-region copy.. Options B and D are correct. Enabling multi-node cluster with RA3 node types provides managed storage and resilience. Enabling cross-region snapshot copy ensures data can be restored in another region. Option A is incorrect because concurrency scaling does not provide high availability. Option C is incorrect because single-node clusters are not highly available. Option E is incorrect because VPC routing does not affect node failure.

Answer

Enable concurrency scaling to handle increased read traffic.

Answer

Deploy the cluster as a single-node cluster for simplicity.

Answer

Place the cluster in a public subnet with an internet gateway.

Question 5

A data engineer notices that an Amazon S3 bucket policy is overly permissive. What is the best practice to restrict access while maintaining required permissions?

Accepted Answer

Attach the AWS managed policy AmazonS3ReadOnlyAccess to the IAM user.. Option A is correct because the AWS managed policy 'AmazonS3ReadOnlyAccess' grants read-only access and is more restrictive than full access. Option B (Deny all) would break applications. Option C (blocklist) is not a standard method. Option D (full access) is the opposite of restriction.

Answer

Grant full S3 access using a new IAM policy.

Answer

Write a new bucket policy that denies all actions.

Answer

Use an S3 blocklist to restrict access.

Question 6

A data pipeline using AWS Glue jobs is failing with 'Insufficient capacity' errors for Spark executors. Which action should the data engineer take to resolve this?

Accepted Answer

Increase the number of workers (DPUs) in the Glue job configuration.. Option B is correct because the error indicates resource limits; increasing the number of workers (DPUs) can resolve capacity issues. Option A (reduce workers) would worsen the problem. Option C (increase timeout) does not address capacity. Option D (disable logging) does not help.

Answer

Reduce the number of workers in the Glue job configuration.

Answer

Increase the job timeout value.

Answer

Disable Spark UI logging.

Question 7

A company is using Amazon Kinesis Data Analytics (now part of Amazon Managed Service for Apache Flink) for streaming data processing. The application is experiencing high latency and the data engineer wants to improve performance. Which THREE actions should the engineer consider? (Choose three.)

Accepted Answer

Use a larger Kinesis data stream with more shards.. Options A, C, and E are correct. Increasing parallelism allows more concurrent processing. Using a larger Kinesis stream with more shards increases ingestion throughput. Increasing the Flink parallelism parameter distributes workload. Option B is incorrect because decreasing the checkpoint interval increases latency. Option D is incorrect because decreasing the buffer time may cause more frequent micro-batches, increasing overhead.

Answer

Decrease the buffer time in the Flink application to reduce latency.

Answer

Decrease the checkpoint interval to reduce state size.

Question 8

A company uses AWS Lake Formation to manage data lake permissions. A data engineer needs to grant a group of analysts SELECT permission on a set of tables in the 'analytics' database, but only for columns that are not classified as 'PII'. Which approach should the engineer use?

Accepted Answer

Use Lake Formation tag-based access control (LF-TBAC) to grant SELECT on columns without the 'PII' tag.. Option C is correct because LF-TBAC allows column-level permissions based on tags. Option A (IAM policy) does not support column-level restrictions. Option B (S3 bucket policy) is too coarse. Option D (database-level grant) grants access to all columns.

Answer

Grant SELECT on the entire database and rely on analysts to avoid PII columns.

Answer

Create an IAM policy that denies access to PII columns.

Answer

Use an S3 bucket policy to restrict access to objects containing PII data.

Question 9

A data engineer is setting up an AWS Glue job to process data from an Amazon S3 bucket. The job fails with an 'Access Denied' error. Which TWO IAM permissions are MOST likely missing from the Glue job's IAM role?

Accepted Answer

s3:PutObject. Options A and C are correct. Glue needs s3:GetObject to read from S3 and s3:PutObject to write output. Option B is incorrect because glue:StartJobRun is not needed for the job itself. Option D is incorrect because kms:Decrypt is needed only if S3 uses KMS encryption. Option E is incorrect because dynamodb:GetItem is not relevant unless accessing DynamoDB.

Answer

kms:Decrypt

Answer

dynamodb:GetItem

Answer

glue:StartJobRun

Question 10

A data engineer is troubleshooting a slow Amazon Redshift query. The EXPLAIN plan shows a 'Seq Scan' on a large table. What is the most likely cause?

Accepted Answer

The table does not have a proper sort key defined.. Option D is correct because 'Seq Scan' indicates a full table scan, which typically occurs when there is no suitable index (or in Redshift, no sort key). Option A (too many nodes) would not cause a Seq Scan. Option B (concurrent queries) could cause slowdown but not a Seq Scan specifically. Option C (WLM queue) affects concurrency, not scan type.

Answer

The cluster has too many nodes.

Answer

There are too many concurrent queries.

Answer

The workload management (WLM) queue is misconfigured.

Question 11

Refer to the exhibit. A data engineer has an IAM policy attached to an IAM role used by an AWS Glue job. The Glue job reads from S3 bucket 'example-bucket' and writes to an S3 bucket 'output-bucket'. The job fails with an 'Access Denied' error when writing to 'output-bucket'. What is the MOST likely cause?

Accepted Answer

The policy does not allow s3:PutObject on 'output-bucket'.. Option B is correct. The policy only allows s3:PutObject on 'example-bucket/*', not on 'output-bucket/*'. The job needs permission on the output bucket. Option A is incorrect because s3:PutObject is allowed on example-bucket, but not on output-bucket. Option C is incorrect because there is no condition that restricts PutObject to example-bucket. Option D is incorrect because the policy allows s3:GetObject on example-bucket, which is for reading.

Answer

The policy does not allow s3:PutObject on any bucket.

Answer

The policy does not allow s3:GetObject on 'output-bucket'.

Answer

The policy has a condition that restricts s3:PutObject to 'example-bucket'.

Question 12

A company uses AWS DMS to migrate data from an on-premises Oracle database to Amazon Aurora MySQL. The migration is successful, but the ongoing replication task is experiencing high latency. Which configuration change is most likely to reduce latency?

Accepted Answer

Increase the size of the DMS replication instance.. Option B is correct because increasing the DMS replication instance size provides more CPU and memory, which can process changes faster. Option A (S3 as target) is not applicable as the target is Aurora. Option C (CDC from binary logs) is for MySQL source. Option D (decrease batch size) would likely increase latency.

Answer

Decrease the task's batch size and batch apply timeout.

Answer

Change the target endpoint to Amazon S3.

Answer

Enable Change Data Capture (CDC) from binary logs.

Question 13

Refer to the exhibit. A data engineer is reviewing the configuration of an Amazon Redshift cluster. The engineer wants to ensure that the cluster can be restored to a point in time up to 35 days in the past. Based on the exhibit, what change is needed?

Accepted Answer

Increase the automated snapshot retention period to 35 days.. Option C is correct. The AutomatedSnapshotRetentionPeriod is set to 1 day, which allows only 1 day of point-in-time recovery. To support 35 days, this value must be increased to 35. Option A is incorrect because the cluster is already encrypted. Option B is incorrect because the number of nodes does not affect snapshot retention. Option D is incorrect because the subnet group does not affect retention.

Answer

Change the cluster subnet group to a custom one.

Answer

Enable encryption on the cluster.

Answer

Increase the number of nodes to 6.

Question 14

A data engineer is designing a data pipeline that ingests JSON files from an S3 bucket, transforms them using AWS Glue, and loads into Amazon Redshift. The data is updated daily, and the pipeline must handle late-arriving data from the previous day. Which approach minimizes reprocessing?

Accepted Answer

Use AWS Glue job bookmarks to process only new files based on S3 event notifications.. Option A is correct because incrementally processing only new files avoids reprocessing. Option B (full reload) is inefficient. Option C (versioning) handles overwrites but not late-arriving data. Option D (Kinesis) is for streaming, not batch with late data.

Answer

Stream data using Amazon Kinesis Data Firehose to Redshift.

Answer

Enable S3 versioning and process only the latest version of each object.

Answer

Schedule a full reload of all data from S3 to Redshift each day.

Question 15

Refer to the exhibit. A data engineer sees this error log from an Amazon EC2 instance that is trying to access an S3 bucket in the us-west-2 region. The EC2 instance is in a VPC with a private subnet and no internet gateway. What is the MOST likely cause of this error?

Accepted Answer

The VPC does not have a VPC endpoint for S3.. Option D is correct. The EC2 instance is in a private subnet without internet gateway, so it cannot reach S3 over the internet. A VPC endpoint (Gateway or Interface) is needed for private connectivity. Option A is incorrect because the bucket exists (DNS resolves). Option B is incorrect because the error is a connection timeout, not a 403. Option C is incorrect because there is no indication of an incorrect region.

Answer

The S3 bucket is in a different region than us-west-2.

Answer

The S3 bucket does not exist.

Answer

The IAM role attached to the EC2 instance does not have s3:GetObject permission.

DEA-C01 Data Operations and Support Practice Test 15 — 15 Questions

Exhibit

DEA-C01 Data Operations and Support Practice Test 15 — 15 Questions

Exhibit