Which tool can be used for transforming data before loading it into Amazon Redshift?

AWS Glue is a fully managed ETL (Extract, Transform, Load) service designed specifically for preparing data for analytics. It provides a flexible framework that simplifies the process of transforming data before loading it into data stores like Amazon Redshift. Glue accomplishes this by allowing users to create and manage ETL jobs that can clean, enrich, and transform data in a scalable manner. It also integrates seamlessly with various data sources and targets, making it a powerful choice for organizations looking to preprocess data for analytics.

The choice of AWS Glue is particularly apt for tasks related to Redshift because it can automatically generate the code required to transform data based on the schema definitions and can work with a variety of data formats. Additionally, its serverless model means that users can focus on developing their data workflows without worrying about the underlying infrastructure.

In contrast, while AWS Lambda is great for running code in response to events, it doesn't directly provide the comprehensive ETL capabilities that Glue offers. Amazon RDS serves as a relational database service and does not have built-in transformation capabilities like Glue. Amazon EC2 can be used to run applications that perform data transformation, but it requires more management and configuration compared to the serverless nature of AWS Glue.