Database setup and configuration

Ory Hydra requires a database to store OAuth 2.0 clients, consent sessions, and access tokens. Choose between two operational modes based on your deployment needs.

In-memory mode

Set DSN=memory to run Hydra with an ephemeral SQLite database. This mode is useful for development and testing but has limitations:

• Data is lost when the instance restarts
• Only single-instance deployments work (no clustering)

SQL mode

For production deployments, configure Hydra with a persistent database. Hydra supports PostgreSQL 12.0+, MySQL 8.0+, CockroachDB, and SQLite. Older MySQL versions have known issues with Hydra's database schema.

Set the database connection using the DSN environment variable or the dsn configuration key.

PostgreSQL:

DSN=postgres://user:password@host:5432/database

MySQL:

DSN=mysql://user:password@tcp(host:3306)/database?parseTime=true

CockroachDB:

DSN=cockroach://user:password@host:26257/database?sslmode=verify-full

SQLite (file-based):

DSN=sqlite:///path/to/hydra.sqlite?_fk=true

The _fk=true parameter is required for SQLite to enable foreign key constraints.

For additional DSN options including SSL/TLS configuration, see Deployment Fundamentals and Requirements.

Running migrations

Hydra doesn't create the database schema automatically. You must run migrations before starting the server and after every upgrade.

Always back up your database before running migrations. For upgrade-specific guidance, see the upgrade instructions.

hydra migrate sql -e

The -e flag reads the DSN from the environment variable.

For Docker deployments, see the docker-compose example.