Ory Hydra uses SQL for its database schema. The SQL adapter supports PostgreSQL 9.6+, MySQL 5.7+, and SQLite. However, it's important to note that older MySQL versions may have issues with Ory Hydra's database schema. To create the database schema, you must run the

hydra migrate sql

command. This command also runs database migrations in case of an upgrade. Always create a backup before running

hydra migrate sql

. For more information on configuring the DSN (Data-Source-Name), you can refer to the [Deployment Fundamentals and Requirements](https://www.ory.sh/docs/ecosystem/deployment) section of the Ory documentation. For more detailed information about the database schema and how to manage it, you can refer to the following sections of the Ory documentation: - [Database setup and configuration](https://www.ory.sh/docs/hydra/self-hosted/dependencies-environment) - [Upgrade instructions](https://github.com/ory/hydra/blob/master/UPGRADE.md) - [FAQ on running migrations](https://www.ory.sh/docs/hydra/faq) Please note that changes to the Ory Hydra SQL schemata should be discussed with maintainers before implementation. Sources: - [Database setup and configuration](https://www.ory.sh/docs/hydra/self-hosted/dependencies-environment) - [Contribute to Ory](https://www.ory.sh/docs/ecosystem/contributing) - [FAQ](https://www.ory.sh/docs/hydra/faq) - [Apply upgrades](https://www.ory.sh/docs/hydra/self-hosted/upgrade)

I'm sorry, but the provided extracts do not contain detailed information about the schema of all the tables used by Ory Hydra. The extracts mention that Ory Hydra uses SQL for its database schema and supports PostgreSQL 9.6+, MySQL 5.7+, and SQLite. However, they do not provide specific details about the schema of each table. For detailed information about the database schema and the schema of each table, I recommend checking the official Ory Hydra documentation or the source code on GitHub.

Sure, you can find the official Ory Hydra documentation at this link: [Ory Hydra Documentation](https://www.ory.sh/docs/hydra/). For detailed information about the database schema, you might need to check the source code directly on GitHub: [Ory Hydra GitHub Repository](https://github.com/ory/hydra).

I'm sorry, but the provided extracts do not contain specific information about the

hydra_oauth2_authentication_request_handled

table used by Ory Hydra. For detailed information about this specific table, I recommend checking the official Ory Hydra documentation or the source code on GitHub.