Which AWS service is ideal for executing ad-hoc queries against large datasets stored in S3?

Amazon Athena is the ideal AWS service for executing ad-hoc queries against large datasets stored in Amazon S3. Athena is a serverless interactive query service that allows users to analyze data in S3 using standard SQL queries. Since it doesn’t require any infrastructure setup, users can simply point Athena to the data stored in S3 and begin querying immediately. It automatically scales to run queries quickly and efficiently on large datasets.

One of the key advantages of using Athena is its ability to work directly with data formats such as CSV, JSON, ORC, Parquet, and Avro. This flexibility allows users to analyze diverse types of data without the need for complex data processing pipelines. Additionally, you only pay for the amount of data scanned by your queries, making it a cost-effective solution for data analysis.

In contrast, AWS Glue is primarily a data integration service used for preparing data and moving it between data stores, rather than executing queries. Amazon Redshift is a fully managed data warehouse service optimized for complex queries and analytics but generally requires data to be loaded into its environment, which is not as immediate as querying directly on S3. Amazon EMR is a big data processing framework that can run Spark, Hadoop, and other distributed processing frameworks, which is