Here’s the difference between Hydra and Oracle. The comparison is based on pricing, deployment, business model, and other important factors.
Hydra is a data warehouse that is accessible from Postgres. You can start for free, begin scaling with Postgres, then switch to the data engine of your choice at any time. It's frictionless to swap back-end engines without lock-in.
Oracle Autonomous Data Warehouse is a cloud data warehouse service that eliminates all the complexities of operating a data warehouse, securing data, and developing data-driven applications. It automates provisioning, configuring, securing, tuning, scaling, and backing up of the data warehouse. It includes tools for self-service data loading, data transformations, business models, automatic insights, and built-in converged database capabilities that enable simpler queries across multiple data types and machine learning analysis. It’s available in both the Oracle public cloud and customers' data centers with Oracle Cloud@Customer.