Amazon Web Services Data-Engineer-Associate - AWS Certified Data Engineer - Associate (DEA-C01)

Problem Analysis:

The company requires a centralized data warehouse for consolidating data from various sources.

They use Amazon QuickSight in direct query mode, necessitating fast response times for analytical queries.

Users query the data intermittently, with unpredictable spikes during the day.

Operational overhead should be minimal.

Key Considerations:

The solution must support fast, SQL-based analytics.

It must handle unpredictable spikes efficiently.

Must integrate seamlessly with QuickSight for direct querying.

Minimize operational complexity and scaling concerns.

Solution Analysis:

Option A: Amazon Redshift Serverless

Redshift Serverless eliminates the need for provisioning and managing clusters.

Automatically scales compute capacity up or down based on query demand.

Reduces operational overhead by handling performance optimization.

Fully integrates with Amazon QuickSight, ensuring low-latency analytics.

Reduces costs as it charges only for usage, making it ideal for workloads with intermittent spikes.

Option B: Amazon Athena with S3 (Apache Parquet)

Athena supports querying data directly from S3 in Parquet format.

While it’s cost-effective, performance depends on the size and complexity of the data.

It is not optimized for high-speed analytics needed by QuickSight in direct query mode.

Option C: Amazon Redshift Provisioned Clusters

Requires manual cluster provisioning, scaling, and maintenance.

Higher operational overhead compared to Redshift Serverless.

Option D: Amazon Aurora PostgreSQL

Aurora is optimized for transactional databases, not data warehousing or analytics.

Does not meet the requirement for fast analytics queries.

Final Recommendation:

Amazon Redshift Serverless is the best choice for this use case because it provides fast analytics, integrates natively with QuickSight, and minimizes operational complexity while efficiently handling unpredictable spikes.

Amazon Redshift Serverless Overview

Amazon QuickSight and Redshift Integration

Athena vs. Redshift

Problem Analysis:

The goal is to create a new empty table in Athena with the same schema as an existing table (old_table).

The solution must avoid copying any data.

Key Considerations:

CREATE TABLE AS (CTAS) is commonly used in Athena for creating new tables based on an existing table.

Adding the WITH NO DATA clause ensures only the schema is copied, without transferring any data.

Solution Analysis:

Option A: Copies both schema and data. Does not meet the requirement for an empty table.

Option B: Inserts data into an existing table, which does not create a new table.

Option C: Creates an empty table but does not copy the schema.

Option D: Creates a new table with the same schema and ensures it is empty by using WITH NO DATA.

Final Recommendation:

Use D. CREATE TABLE new_table AS (SELECT * FROM old_table) WITH NO DATA to create an empty table with the same schema.

Athena CTAS Queries

CREATE TABLE Statement in Athena

Option A is correct because this is a sequential, dependent workflow where each validation stage depends on the previous one, and the overall execution can last up to 24 hours. AWS states that Standard Workflows in Step Functions are ideal for long-running, durable, auditable workflows and can run for up to one year. AWS also documents the Wait for a Callback with Task Token pattern, which is specifically designed for workflows that must pause until an external process reports completion. That maps directly to multi-level validations that may complete asynchronously but still need orchestration within a bounded window.

Option B is incorrect because Express Workflows can run for only up to five minutes, so they cannot support a transaction workflow that may take many hours. Option C adds more custom code and operational management than Step Functions and does not naturally provide the same stateful orchestration, dependency tracking, and callback waiting pattern. Option D is also more operationally heavy and is better suited to data pipeline orchestration than per-transaction validation workflows. Therefore, Standard Step Functions provides the lowest operational cost while fully meeting the timing and dependency requirements.

In Amazon Redshift, the SUPER data type is designed specifically to handle semi-structured data like JSON, Parquet, ORC, and others. By using the SUPER data type, Redshift can ingest and query JSON data without requiring complex data flattening processes, thus reducing the amount of preprocessing required before loading the data. The SUPER data type also works seamlessly with Redshift Spectrum, enabling complex queries that can combine both structured and semi-structured datasets, which aligns with the company’s need to use combined datasets to identify potential new customers.

Using the SUPER data type also allows for automatic parsing and query processing of nested data structures through Amazon Redshift ' s PARTITION BY and JSONPATH expressions, which makes this option the most efficient approach with the least effort involved. This reduces the overhead associated with using tools like AWS Glue or Lambda for data transformation.

Amazon Redshift Documentation - SUPER Data Type

AWS Certified Data Engineer - Associate Training: Building Batch Data Analytics Solutions on AWS

AWS Certified Data Engineer - Associate Study Guide

By directly leveraging the capabilities of Redshift with the SUPER data type, the data engineer ensures streamlined JSON ingestion with minimal effort while maintaining query efficiency.

DynamoDB Time to Live (TTL) automatically expires and deletes items based on a timestamp attribute — it requires minimal setup and runs without additional infrastructure.

The engineer only needs to define a TTL attribute (e.g., expiration_time) and set its epoch value when items are inserted.

“To automatically delete old items from a DynamoDB table, enable TTL and define a timestamp attribute. Items are removed automatically after the specified time with no extra maintenance.”

– Ace the AWS Certified Data Engineer - Associate Certification - version 2 - apple.pdf

This is serverless, free, and requires no scheduling or code-based cleanup.

Problem Analysis:

The pipeline processes compressed files in S3 and must support incremental data processing.

AWS Glue features must facilitate tracking progress to avoid reprocessing the same data.

Key Considerations:

Incremental data processing requires tracking which files or partitions have already been processed.

The solution must be automated and efficient for large-scale ETL jobs.

Solution Analysis:

Option A: Workflows

Workflows organize and orchestrate multiple Glue jobs but do not track progress for incremental data processing.

Option B: Triggers

Triggers initiate Glue jobs based on a schedule or events but do not track which data has been processed.

Option C: Job Bookmarks

Job bookmarks track the state of the data that has been processed, enabling incremental processing.

Automatically skip files or partitions that were previously processed in Glue jobs.

Option D: Classifiers

Classifiers determine the schema of incoming data but do not handle incremental processing.

Final Recommendation:

Job bookmarks are specifically designed to enable incremental data processing in AWS Glue ETL pipelines.

AWS Glue Job Bookmarks Documentation

AWS Glue ETL Features

AWS Lambda is a serverless compute service that lets you run code without provisioning or managing servers. You can use Lambda to create functions that perform custom logic and integrate with other AWS services, such as API Gateway. Lambda automatically scales your application by running code in response to each trigger. You pay only for the compute time you consume1.

Amazon ECS is a fully managed container orchestration service that allows you to run and scale containerized applications on AWS. You can use ECS to deploy, manage, and scale Docker containers using either Amazon EC2 instances or AWS Fargate, a serverless compute engine for containers2.

Amazon EKS is a fully managed Kubernetes service that allows you to run Kubernetes clusters on AWS without needing to install, operate, or maintain your own Kubernetes control plane. You can use EKS to deploy, manage, and scale containerized applications using Kubernetes on AWS3.

The solution that meets the requirements with the least operational overhead is to create an AWS Lambda Python function with provisioned concurrency. This solution has the following advantages:

It does not require you to provision, manage, or scale any servers or clusters, as Lambda handles all the infrastructure for you. This reduces the operational complexity and cost of running your code.

It allows you to write your Python script as a Lambda function and integrate it with API Gateway using a simple configuration. API Gateway can invoke your Lambda function synchronously or asynchronously, and return the results to the frontend website.

It ensures that your Lambda function is ready to respond to API requests without any cold start delays, by using provisioned concurrency. Provisioned concurrency is a feature that keeps your function initialized and hyper-ready to respond in double-digit milliseconds. You can specify the number of concurrent executions that you want to provision for your function.

Option A is incorrect because it requires you to deploy a custom Python script on an Amazon ECS cluster. This solution has the following disadvantages:

It requires you to provision, manage, and scale your own ECS cluster, either using EC2 instances or Fargate. This increases the operational complexity and cost of running your code.

It requires you to package your Python script as a Docker container image and store it in a container registry, such as Amazon ECR or Docker Hub. This adds an extra step to your deployment process.

It requires you to configure your ECS cluster to integrate with API Gateway, either using an Application Load Balancer or a Network Load Balancer. This adds another layer of complexity to your architecture.

Option C is incorrect because it requires you to deploy a custom Python script that can integrate with API Gateway on Amazon EKS. This solution has the following disadvantages:

It requires you to provision, manage, and scale your own EKS cluster, either using EC2 instances or Fargate. This increases the operational complexity and cost of running your code.

It requires you to package your Python script as a Docker container image and store it in a container registry, such as Amazon ECR or Docker Hub. This adds an extra step to your deployment process.

It requires you to configure your EKS cluster to integrate with API Gateway, either using an Application Load Balancer, a Network Load Balancer, or a service of type LoadBalancer. This adds another layer of complexity to your architecture.

Option D is incorrect because it requires you to create an AWS Lambda function and ensure that the function is warm by scheduling an Amazon EventBridge rule to invoke the Lambda function every 5 minutes by using mock events. This solution has the following disadvantages:

It does not guarantee that your Lambda function will always be warm, as Lambda may scale down your function if it does not receive any requests for a long period of time. This may cause cold start delays when your function is invoked by API Gateway.

It incurs unnecessary costs, as you pay for the compute time of your Lambda function every time it is invoked by the EventBridge rule, even if it does not perform any useful work1.

1: AWS Lambda - Features

2: Amazon Elastic Container Service - Features

3: Amazon Elastic Kubernetes Service - Features

[4]: Building API Gateway REST API with Lambda integration - Amazon API Gateway

[5]: Improving latency with Provisioned Concurrency - AWS Lambda

[6]: Integrating Amazon ECS with Amazon API Gateway - Amazon Elastic Container Service

[7]: Integrating Amazon EKS with Amazon API Gateway - Amazon Elastic Kubernetes Service

[8]: Managing concurrency for a Lambda function - AWS Lambda

Problem Analysis:

The company needs cross-account access to allow QuickSight in BI-Account to interact with an S3 bucket in Hub-Account.

The bucket is encrypted with an AWS KMS key.

Appropriate permissions must be set for both S3 access and KMS decryption.

Key Considerations:

QuickSight requires IAM permissions to access S3 data and decrypt files using the KMS key.

Both S3 and KMS permissions need to be properly configured across accounts.

Solution Analysis:

Option A: Use Existing KMS Key for Encryption

While the existing KMS key is used for encryption, it must also grant decryption permissions to QuickSight.

Option B: Add S3 Bucket to QuickSight Role

Granting S3 bucket access to the QuickSight service role is necessary for cross-account access.

Option C: AWS RAM for Bucket Sharing

AWS RAM is not required; bucket policies and IAM roles suffice for granting cross-account access.

Option D: IAM Policy for KMS Access

QuickSight’s service role in BI-Account needs explicit permissions to use the KMS key for decryption.

Option E: Add KMS Key as Resource for Role

The KMS key must explicitly list the QuickSight role as an entity that can access it.

Implementation Steps:

S3 Bucket Policy in Hub-Account:Add a policy to the S3 bucket granting the QuickSight service role access:

json

{

" Version " : " 2012-10-17 " ,

" Statement " : [

{

" Effect " : " Allow " ,

" Principal " : { " AWS " : " arn:aws:iam:: < BI-Account-ID > :role/service-role/QuickSightRole " },

" Action " : " s3:GetObject " ,

" Resource " : " arn:aws:s3::: < Bucket-Name > /* "

}

]

}

KMS Key Policy in Hub-Account:Add permissions for the QuickSight role:

{

" Version " : " 2012-10-17 " ,

" Statement " : [

{

" Effect " : " Allow " ,

" Principal " : { " AWS " : " arn:aws:iam:: < BI-Account-ID > :role/service-role/QuickSightRole " },

" Action " : [

" kms:Decrypt " ,

" kms:DescribeKey "

],

" Resource " : " * "

}

]

}

IAM Policy for QuickSight Role in BI-Account:Attach the following policy to the QuickSight service role:

{

" Version " : " 2012-10-17 " ,

" Statement " : [

{

" Effect " : " Allow " ,

" Action " : [

" s3:GetObject " ,

" kms:Decrypt "

],

" Resource " : [

" arn:aws:s3::: < Bucket-Name > /* " ,

" arn:aws:kms: < region > : < Hub-Account-ID > :key/ < KMS-Key-ID > "

]

}

]

}

Setting Up Cross-Account S3 Access

AWS KMS Key Policy Examples

Amazon QuickSight Cross-Account Access

The STL ALERT EVENT LOG table view records anomalies when the query optimizer identifies conditions that might indicate performance issues. These conditions include skewed data distribution, missing statistics, nested loop joins, and broadcasted data. The STL ALERT EVENT LOG table view can help the data engineer to identify and troubleshoot the root causes of performance issues and optimize the query execution plan. The other table views are not relevant for this requirement. STL USAGE CONTROL records the usage limits and quotas for Amazon Redshift resources. STL QUERY METRICS records the execution time and resource consumption of queries. STL PLAN INFO records the query execution plan and the steps involved in each query. References:

STL ALERT EVENT LOG

System Tables and Views

AWS Certified Data Engineer - Associate DEA-C01 Complete Study Guide