Postgres

DATABASE_URI format should be postgresql://<user>:<pass>@<host>:<port>/<database>

Example:

DATABASE_URI=postgresql://user:pass@localhost:5432/llana

MySQL

DATABASE_URI format should be mysql://<user>:<pass>@<host>:<port>/<database>

MongoDB

DATABASE_URI format should be mongodb://<user>:<pass>@<host>:<port>/<database>