Amazon Redshift extends data warehouse queries to your data lake, with no loading required.
You can run analytic queries against petabytes of data stored locally in Redshift, and
directly against exabytes of data stored in Amazon S3
Amazon RDS is not a data warehouse and cannot query data in S3 at rest
AWS Lambda runs code as functions and is not a data warehouse
Amazon Elastic Map Reduce (EMR) provides a managed Hadoop service and cannot query data in
S3 at rest