Databases

Ployz adds PostgreSQL, MySQL, Redis or MongoDB to your environment in one step, with a volume for its data, a generated password and the variables your app needs to connect. After that, it's an ordinary service you can change like any other.

Add a database

On your project's canvas, click Create.
Choose Database, then PostgreSQL, MySQL, Redis or MongoDB.
Its data goes on a 5 GB volume. For more room, click the volume, change Storage limit (GB) and click Save storage now: you can't after you deploy it.
Click Deploy.

You get a service named after the database. Its connection variables are exported for your other services to reference, and its password is sealed. They use Railway's names, like PGHOST and PGPASSWORD, so an app moving from Railway can keep reading them.

	Version	Service	URL variable	Port	User
PostgreSQL	18	`postgres`	`DATABASE_URL`	5432	`postgres`
MySQL	9.4	`mysql`	`MYSQL_URL`	3306	`root`
Redis	8.2	`redis`	`REDIS_URL`	6379	`default`
MongoDB	8.0	`mongodb`	`MONGO_URL`	27017	`mongo`

PostgreSQL and MySQL start with a database named ployz.

Connect your app

Open your app's service, go to Variables and click New Variable.
Enter DATABASE_URL as the Key, and untick Sealed: a sealed value can't hold a reference. The password inside stays hidden anyway.
Enter ${{ postgres.DATABASE_URL }} as the Value and click Add.
Click Deploy.

The New Variable dialog suggesting postgres.DATABASE_URL as you type a reference

The URL points at the database's private address, like postgres.internal, so the connection stays on your servers' private network. Ployz starts the database before your app on every deploy. See Variables for more on references.

Connect from your laptop

Databases have no public address. To reach one from your computer, forward a port to it. This is CLI-only for now (install the CLI first):

# Forward 127.0.0.1:5432 to the database, until you press Ctrl-C
ployz service port-forward postgres 5432:5432

# In another terminal: read the sealed password, then connect
ployz exec postgres -- printenv POSTGRES_PASSWORD
psql -h 127.0.0.1 -U postgres ployz

If 5432 is taken on your laptop, pick another local port, like 15432:5432.

Back up a database

Dump each database on a schedule, from a computer you trust or a CI job, and store the dumps away from your servers, such as in object storage. A dump kept on the same server is lost with it. Dumps are CLI-only for now. Keep -T: it sends the dump to the file unchanged.

# PostgreSQL
ployz exec -T postgres -- pg_dump --format=custom > postgres.dump

# MySQL
ployz exec -T mysql -- sh -c 'mysqldump -u root -p"$MYSQL_ROOT_PASSWORD" --single-transaction "$MYSQL_DATABASE"' > mysql.sql

# Redis
ployz exec -T redis -- sh -c 'redis-cli -a "$REDIS_PASSWORD" --no-auth-warning --rdb -' > redis.rdb

# MongoDB
ployz exec -T mongodb -- sh -c 'mongodump --archive -u "$MONGO_INITDB_ROOT_USERNAME" -p "$MONGO_INITDB_ROOT_PASSWORD" --authenticationDatabase admin' > mongo.archive

Restore a PostgreSQL dump the same way, and try it before you need it:

ployz exec -T postgres -- pg_restore --clean --if-exists -d ployz < postgres.dump

Use a managed database instead

To keep your database at a provider such as Amazon RDS, Neon or PlanetScale, skip the preset. Add the provider's connection URL to your app as a sealed variable named DATABASE_URL, then click Deploy. If the provider only accepts known IP addresses, allow your servers' public IPs.

Good to know

The password is set once. PostgreSQL, MySQL and MongoDB read their password only when they first set up their volume. If you change the password variable later, change it in the database too, or your app can't connect. Redis reads REDIS_PASSWORD each time it starts.
Redis can lose its last minute of writes if it crashes.
Deleting a database deletes its data. Deleting its service in the dashboard also deletes its volume, unless another service mounts it. The deploy asks you to confirm first.

Next: test changes in a preview environment.