Guides

Databases

Choosing SQLite, PostgreSQL or MySQL with one address, and leaving out the drivers you do not use.

The address in DATABASE_URL (the database.url setting) chooses the database. Every driver is built in, so switching is a change to .env, not to the code:

Database	`DATABASE_URL`
SQLite	`sqlite://db.sqlite3?mode=rwc` (`mode=rwc` creates the file)
PostgreSQL	`postgres://user:password@host:5432/name`
MySQL and MariaDB	`mysql://user:password@host:3306/name`

cadmus new blog --database postgres (or mysql) starts a project with such an address to fill in. Run cargo run -- migrate against a new database to create its tables.

Oracle and SQL Server are not supported: SeaORM, the database layer, has no open-source driver for them.

#The same behaviour everywhere

The admin and the API behave the same on all three: true and false are JSON booleans, dates and times are ISO 8601 (2026-03-04T05:06:07), JSON fields come back as JSON, and ?q= search ignores case. Migrations are written once and turned into the right SQL for each. Cadmus's own tests run on all three.

#Connections

database: DatabaseSettings {
    url: env("DATABASE_URL")?,
    max_connections: Some(20),
    min_connections: Some(2),
    acquire_timeout: Some(Duration::from_secs(5)),
},

#Smaller builds

A project that only uses one database can leave the other drivers out, to compile faster:

cadmus = { version = "0.1", default-features = false, features = ["postgres"] }

The features are sqlite, postgres and mysql. An address for a driver that was left out stops start-up and names the feature to turn back on.