Trino

Trino queries across all your data sources (Postgres, S3, Elasticsearch, spreadsheets) with standard SQL. It's a distributed SQL query engine that connects to dozens of data sources and lets you join across them like they're one database.

Formerly known as PrestoSQL (the original creators of Presto at Facebook forked after a dispute), Trino is the community-driven continuation. Apache 2.0, used by companies like Netflix, LinkedIn, and Lyft.

The engine is free. Managed options include Starburst (the commercial company founded by Trino's creators) starting around $2/hr for a small cluster, and AWS Athena which is Trino under the hood at $5/TB scanned.

The catch: Trino is a query engine, not a database. It doesn't store data; it reads from where your data already lives. Running it yourself means managing a coordinator + workers cluster, which is real ops work. And for single-source queries, it's slower than querying that source directly. Trino shines specifically when you need to federate across multiple sources.