AWS Certified Associate Data-Engineer-Associate Exam Questions and Answers PDF

To reclaim the most storage space from a materialized view in Amazon Redshift, you should use a DELETE operation that removes all rows from the view. The most efficient way to remove all rows is to use a condition that always evaluates to true, such as 1=1. This will delete all rows without needing to evaluate each row individually based on specific column values like load_date.

Option A: DELETE FROM materialized_view_name WHERE 1=1;This statement will delete all rows in the materialized view and free up the space. Since materialized views in Redshift store precomputed data, performing a DELETE operation will remove all stored rows.

Other options either involve inappropriate SQL statements (e.g., VACUUM in option C is used for reclaiming storage space in tables, not materialized views), or they don’t remove data effectively in the context of a materialized view (e.g., TRUNCATE cannot be used directly on a materialized view).

Amazon Athena Federated Query is a feature that allows you to query data from multiple sources using standard SQL. You can use Athena Federated Query to join data from Amazon DynamoDB, Amazon RDS, Amazon Redshift, and Amazon S3, as well as other data sources such as MongoDB, Apache HBase, and Apache Kafka1. Athena Federated Query is a serverless and interactive service, meaning you do not need to provision or manage any infrastructure, and you only pay for the amount of data scanned by your queries. Athena Federated Query is the most cost-effective solution for performing a one-time analysis job on data from multiple sources, as it eliminates the need to copy or move data, and allows you to query data directly from the source.

The other options are not as cost-effective as Athena Federated Query, as they involve additional steps or costs. Option A requires you to provision and pay for an Amazon EMR cluster, which can be expensive and time-consuming for a one-time job. Option B requires you to copy or move data from DynamoDB, RDS, and Redshift to S3, which can incur additional costs for data transfer and storage, and also introduce latency and complexity. Option D requires you to have an existing Redshift cluster, which can be costly and may not be necessary for a one-time job. Option D also does not support querying data from RDS directly, so you would need to use Redshift Federated Query to access RDS data, which adds another layer of complexity2. References:

Amazon Athena Federated Query

Redshift Spectrum vs Federated Query

Problem Analysis:

The company needs near real-time replication of MySQL updates to Amazon Redshift.

Minimal development effort is required for this solution.

Key Considerations:

AWS DMS provides a full load + CDC (Change Data Capture) mode for continuous replication of database changes.

DMS integrates natively with both MySQL and Redshift, simplifying setup.

Solution Analysis:

Option A: AWS Glue Job

Glue is batch-oriented and does not support near real-time replication.

Option B: DMS with Full Load + CDC

Efficiently handles initial database load and continuous updates.

Requires minimal setup and operational overhead.

Option C: AppFlow SDK

AppFlow is not designed for database replication. Custom connectors increase development effort.

Option D: DataSync

DataSync is for file synchronization and not suitable for database updates.

Final Recommendation:

Use AWS DMS in full load + CDC mode for continuous replication.

AWS Database Migration Service Documentation

Setting Up DMS with Redshift

Problem Analysis:

The company needs to migrate both an application and an on-premises Apache Kafka server to AWS.

Incremental updates from an on-premises Oracle database are processed by Kafka.

The solution must follow a replatform migration strategy, prioritizing minimal changes and low management overhead.

Key Considerations:

Replatform Strategy: This approach keeps the application and architecture as close to the original as possible, reducing the need for refactoring.

The solution must provide a managed Kafka service to minimize operational burden.

Low overhead solutions like serverless services are preferred.

Solution Analysis:

Option A: Kinesis Data Streams

Kinesis Data Streams is an AWS-native streaming service but is not a direct substitute for Kafka.

This option would require significant application refactoring, which does not align with the replatform strategy.

Option B: MSK Provisioned Cluster

Managed Kafka service with fully configurable clusters.

Provides the same Kafka APIs but requires cluster management (e.g., scaling, patching), increasing management overhead.

Option C: Amazon Kinesis Data Firehose

Kinesis Data Firehose is designed for data delivery rather than real-time streaming and processing.

Not suitable for Kafka-based applications.

Option D: MSK Serverless

MSK Serverless eliminates the need for cluster management while maintaining compatibility with Kafka APIs.

Automatically scales based on workload, reducing operational overhead.

Ideal for replatform migrations, as it requires minimal changes to the application.

Final Recommendation:

Amazon MSK Serverless is the best solution for migrating the Kafka server and application with minimal changes and the least management overhead.

Amazon MSK Serverless Overview

Comparison of Amazon MSK and Kinesis