What service would you use for data warehousing in AWS?

Amazon Redshift is the most suitable choice for data warehousing in AWS due to its design and optimization specifically for large scale data analytics. As a fully managed, petabyte-scale data warehouse service, it enables you to run complex queries and perform analytics on massive datasets rapidly.

Redshift uses a columnar storage format that significantly optimizes data compression and improves query performance. It also integrates well with various business intelligence (BI) tools to facilitate data visualization and reporting, thus making it a comprehensive solution for data warehousing needs.

In contrast, other options serve different purposes. Amazon Athena is primarily a serverless query service that allows you to analyze data in Amazon S3 using standard SQL. It is convenient for ad-hoc queries but is not structured as a data warehousing solution. Amazon RDS is a relational database service, suitable for OLTP (online transaction processing) workloads rather than large-scale analytical querying. Lastly, Amazon DynamoDB is a NoSQL database designed for high throughput and low-latency needs, but it does not fit the role of a data warehouse.

Each of these services has unique strengths, but for a dedicated data warehousing solution, Amazon Redshift is the clear choice.