DEA-C01 Data Ingestion and Transformation Practice Test 9 — 15 Questions

Question 1

A data engineer has an IAM policy attached to an IAM role used by an AWS Glue job. The Glue job needs to read from S3 bucket 'data-bucket' and write to the same bucket. The job fails with an access denied error when trying to write to S3. What is the issue?

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

Accepted Answer

The policy does not include s3:ListBucket permission, which Glue may need.. AWS Glue jobs require the `s3:ListBucket` permission on the bucket to perform operations like listing objects, even when reading and writing specific keys. Without this permission, the job fails with an access denied error when trying to write, as Glue internally uses `ListBucket` to verify bucket existence and access patterns. The policy attached to the IAM role likely includes `s3:GetObject` and `s3:PutObject` but omits the bucket-level `s3:ListBucket` action, which is necessary for the Glue job to interact with S3 successfully.

Answer

The Glue job cannot assume the IAM role because of trust policy.

Answer

The resource ARN for S3 is missing the bucket-level permission.

Answer

The actions for S3 are incorrect; s3:PutObject is not sufficient.

Question 2

A data engineer is troubleshooting a Lambda function that reads from the Kinesis stream 'my-data-stream'. The Lambda function is able to read data but occasionally fails with 'KMS.AccessDeniedException'. What is the most likely cause?

Accepted Answer

The Lambda function's execution role does not have kms:Decrypt permission for the KMS key.. The KMS.AccessDeniedException indicates that the Lambda function's execution role lacks the kms:Decrypt permission for the AWS KMS key used to encrypt the Kinesis stream. When a Kinesis stream is encrypted with a customer managed KMS key, the consumer (Lambda) must have explicit decrypt permissions on that key to read the data records.

Answer

The retention period is too short; increase it.

Answer

The stream has too few shards; increase shard count.

Answer

The Lambda function is not authorized to consume from Kinesis streams.

Question 3

A CloudFormation template defines an AWS Glue job. The job fails during execution with the error 'Unable to locate script: s3://scripts-bucket/etl-script.py'. The S3 bucket 'scripts-bucket' exists and the script file is present. What is the most likely cause?

Accepted Answer

The IAM role for the Glue job does not have s3:GetObject permission on the scripts bucket.. The Glue job fails to locate the script because the IAM role assigned to the job lacks the s3:GetObject permission on the scripts-bucket. Even though the bucket and object exist, AWS Glue requires the execution role to have explicit read access to the S3 object to download and execute the script. Without this permission, the job cannot retrieve the file, resulting in the 'Unable to locate script' error.

Answer

The script location path is incorrect; it should include the bucket's region.

Answer

The Glue job requires Python version 2, but the script uses Python 3 syntax.

Answer

The S3 bucket is in a different AWS region than the Glue job.

Question 4

A company is ingesting streaming data from IoT devices into Amazon Kinesis Data Streams. The data must be transformed in real-time and then stored in Amazon S3. Which AWS service should be used to perform the transformation?

Accepted Answer

Amazon Kinesis Data Analytics. Amazon Kinesis Data Analytics (now part of Amazon Managed Service for Apache Flink) is the correct choice because it can consume streaming data from Kinesis Data Streams, apply real-time transformations using SQL or Apache Flink, and then output the transformed data to destinations like Amazon S3. This directly meets the requirement for real-time transformation of streaming IoT data before storage.

Answer

AWS Glue

Answer

Amazon EMR

Answer

Amazon Athena

Question 5

A data engineering team needs to load data from an on-premises Oracle database to Amazon S3 daily. The data volume is about 50 GB per day, and the network bandwidth is 100 Mbps. The team wants to minimize operational overhead and use AWS managed services. Which solution should they choose?

Accepted Answer

Use AWS Database Migration Service (DMS) to migrate the data to S3.. AWS DMS is the correct choice because it is purpose-built for migrating databases to AWS with minimal operational overhead. It can connect to an on-premises Oracle database via a JDBC or native Oracle connection, perform a full load, and then continuously replicate changes to an S3 target in Parquet or CSV format. With 50 GB/day over 100 Mbps (about 10.8 GB/hour theoretical max), the full load can complete in under 5 hours, and ongoing replication handles daily increments without manual intervention.

Answer

Use AWS DataSync to copy the database files directly to S3.

Answer

Use AWS Glue with a JDBC connection and schedule a crawler to load data into S3.

Answer

Use Amazon Kinesis Data Firehose to stream data from Oracle to S3.

Question 6

A company uses Amazon Kinesis Data Streams with a shard count of 10 to ingest clickstream data. The data is consumed by a Lambda function that transforms the records and writes to Amazon S3. Recently, the Lambda function started failing with 'ProvisionedThroughputExceededException' errors. The average record size is 5 KB, and the incoming data rate is 15 MB/s. What is the most likely cause and solution?

Accepted Answer

Increase the number of shards in the Kinesis data stream to 15.. The ProvisionedThroughputExceededException indicates that the total write throughput to the Kinesis stream is exceeding the provisioned capacity. With 10 shards, the maximum write throughput is 10 MB/s (1 MB/s per shard). The incoming data rate is 15 MB/s, which exceeds this limit, causing the error. Increasing the shard count to 15 raises the write throughput to 15 MB/s, matching the incoming rate and resolving the issue.

Answer

Decrease the batch size of the Lambda event source mapping.

Answer

Increase the Lambda function's memory allocation to 3008 MB.

Answer

Increase the Lambda function's reserved concurrency.

Question 7

A data engineer needs to ingest data from an external partner's FTP server to Amazon S3. The data arrives once daily as a CSV file. Which AWS service should be used for this ingestion?

Accepted Answer

AWS Transfer Family. AWS Transfer Family provides fully managed support for file transfers over SFTP, FTPS, and FTP protocols, making it the correct choice for ingesting CSV files from an external partner's FTP server. It integrates directly with Amazon S3 as a destination, enabling automated, secure, and scheduled transfers without custom infrastructure.

Answer

AWS DataSync

Answer

Amazon Kinesis Data Firehose

Answer

Amazon AppFlow

Question 8

A company uses AWS Glue to transform data in S3. The transformation job reads Parquet files, filters rows, and writes to another S3 bucket. The job takes longer than expected. Which change would MOST likely reduce the job execution time?

Accepted Answer

Increase the number of DPUs allocated to the Glue job.. Increasing the number of DPUs (Data Processing Units) allocated to the Glue job directly increases the parallelism of the Apache Spark-based execution environment. Since the job reads Parquet files, filters rows, and writes output, a bottleneck in compute capacity is the most likely cause of prolonged execution time. More DPUs allow Spark to distribute the workload across more executors, reducing overall runtime.

Answer

Use a single large file instead of multiple small files.

Answer

Reduce the number of partitions in the output data.

Answer

Convert the input files from Parquet to CSV format.

Question 9

A data pipeline uses Amazon Kinesis Data Firehose to deliver data to an S3 bucket. The delivery stream is configured with a buffer interval of 60 seconds and a buffer size of 5 MB. The data arrives at an average rate of 2 MB per second. What is the expected time interval between S3 writes?

Accepted Answer

Approximately 2.5 seconds. Amazon Kinesis Data Firehose writes to S3 when either the buffer interval (60 seconds) or buffer size (5 MB) is reached first. With data arriving at 2 MB/s, the 5 MB buffer fills in 2.5 seconds (5 MB / 2 MB/s), triggering a write before the 60-second interval expires. Thus, the expected time between S3 writes is approximately 2.5 seconds.

Answer

Approximately 30 seconds

Answer

Approximately 60 seconds

Answer

Approximately 10 seconds

Question 10

A company wants to ingest real-time data from a social media API into Amazon S3 for analysis. The API provides data as JSON records. Which AWS service is best suited for this ingestion?

Accepted Answer

Amazon Kinesis Data Firehose. Amazon Kinesis Data Firehose is the best choice because it is a fully managed service designed to ingest real-time streaming data, such as JSON records from a social media API, and automatically load it into Amazon S3 with optional data transformation and compression. It handles scaling, buffering, and delivery without requiring custom code or infrastructure management, making it ideal for this use case.

Answer

AWS Glue

Answer

Amazon Simple Queue Service (SQS)

Answer

Amazon DataZone

Question 11

A data engineer needs to transform JSON data into Parquet format using AWS Glue. The input data has nested fields. Which Glue feature should be used to flatten the nested structure?

Accepted Answer

Relationalize transform. The Relationalize transform is the correct choice because it is specifically designed to flatten nested JSON structures (such as arrays and structs) into a set of related tables (DataFrames) that can be written as Parquet. This transform recursively extracts nested fields, creating separate DataFrames for each level of nesting, which is essential for converting complex JSON into a flat, columnar Parquet format suitable for analytics.

Answer

DropNullFields transform

Answer

FindMatches transform

Answer

Map transform

Question 12

A company uses Amazon Kinesis Data Streams with enhanced fan-out consumers. The stream has 5 shards. Each consumer reads from all shards. The total incoming data rate is 25 MB/s. What is the maximum read throughput per consumer if enhanced fan-out is enabled?

Accepted Answer

10 MB/s. With enhanced fan-out, each consumer gets a dedicated 2 MB/s read throughput per shard. Since the stream has 5 shards, the maximum read throughput per consumer is 5 shards × 2 MB/s = 10 MB/s. This is because enhanced fan-out eliminates the 2 MB/s total read limit per shard shared among all consumers, providing each consumer with its own 2 MB/s pipe per shard.

Answer

2 MB/s

Answer

1 MB/s

Answer

5 MB/s

Question 13

A company needs to ingest streaming data from thousands of IoT devices. The data must be processed in real-time and stored in Amazon S3. Which TWO services should be used together?

Accepted Answer

Amazon Kinesis Data Streams. Amazon Kinesis Data Streams is correct because it provides a scalable, real-time data ingestion service that can capture streaming data from thousands of IoT devices with low latency. Amazon Kinesis Data Firehose is correct because it can directly consume data from Kinesis Data Streams and automatically deliver it to Amazon S3 without requiring custom code for buffering, transformation, or loading.

Answer

AWS Glue

Answer

Amazon Simple Queue Service (SQS)

Answer

AWS Direct Connect

Question 14

A data engineer needs to transform data in Amazon S3 using AWS Glue. The job must handle schema evolution and partition pruning. Which THREE features should be used?

Accepted Answer

AWS Glue Data Catalog. AWS Glue Data Catalog (A) is correct because it acts as a central metadata repository that stores table definitions and schema information. When schema evolution occurs (e.g., new columns are added in Parquet or JSON data), the Data Catalog can be updated via crawlers or manual schema registration, allowing Glue ETL jobs to dynamically adapt to changing schemas without hardcoding column structures.

Answer

AWS Glue job bookmarks

Answer

AWS Glue FindMatches transform

Question 15

Which TWO AWS services can be used to ingest data from an on-premise relational database into Amazon S3 on a one-time basis?

Accepted Answer

AWS Database Migration Service (DMS). AWS DMS can perform one-time full-load migrations from on-premise relational databases to Amazon S3 by connecting to the source and writing data directly to S3 in formats like CSV or Parquet. AWS Glue can also be used for one-time data ingestion by creating an ETL job that reads from the source database via JDBC and writes to S3, with the option to run the job on demand. Both services support one-time transfers without ongoing replication.

Answer

AWS Data Pipeline

Answer

Amazon Simple Queue Service (SQS)

Answer

Amazon Kinesis Data Streams