Databases

OwnStack apps can have one or more linked databases. Each is a dokku service running on the same stack as the app, with its data on the stack's disk. Postgres is first-class; MySQL, MongoDB, and Redis are all supported.

How databases relate to apps

A database is a service on the stack — a running container with its own disk. Linking a service to an app sets DATABASE_URL (or REDIS_URL, MONGO_URL, etc.) as a config var. Your app reads it from the environment.

Database	Service prefix	App env var(s)	Default version
Postgres	`postgres-…`	`DATABASE_URL`, `DOKKU_POSTGRES_*_URL`	17 (configurable)
MySQL	`mysql-…`	`DATABASE_URL`, `DOKKU_MYSQL_*_URL`	8
MongoDB	`mongo-…`	`MONGO_URL`, `MONGODB_URI`	7
Redis	`redis-…`	`REDIS_URL`	7

Provisioning

For Rails apps with app_type: rails, OwnStack auto-creates a Postgres service named postgres-<app> on first deploy and links it. Same for NestJS apps — gets MongoDB. For other app types, opt in:

$ ownstack db create --app=<app> [--version=17]

Behind the scenes this runs dokku postgres:create + postgres:link, refreshes DATABASE_URL, and triggers a restart so the app picks up the new env.

Inspecting

$ ownstack db check                          # connectivity + auth, surfaces password drift
$ ownstack db status                         # running/stopped state
$ ownstack db version                        # Postgres version
$ ownstack stack data databases <stack>      # every database on the stack

Common operations

Task	Where to read
Create + link a Postgres	Postgres overview
Stream a binary dump down	Postgres dumps
Restore from a dump or backup	Postgres restore
Fix `password authentication failed` after restore	Repair after import
MySQL specifics	MySQL
Redis specifics	Redis

External databases (RDS, Cloud SQL, etc.)

You don't have to run your DB on the stack. Set needs_postgres: false on the app, point DATABASE_URL at your external DB, and OwnStack stops auto-creating per-stack services:

$ ownstack config:set --app=<app> \
    DATABASE_URL='postgresql://user:pass@my-rds-endpoint:5432/dbname'

Useful for big workloads that benefit from managed Postgres (HA, snapshots, point-in-time recovery) and for apps that deploy to multiple stacks but want one DB.