My app can't reach its database

connect ECONNREFUSED 127.0.0.1:5432, dial tcp [::1]:5432: connect: connection refused, SQLSTATE[HY000] [2002] Connection refused.

There's no database inside your app's container. The app falls back to localhost because it didn't get a database address: no database is linked, or the address it reads is empty or wrong.

1. Link a database in the project's Database tab (create one if you have none).

2. In Variables, delete any DATABASE_URL or DB_HOST you set yourself: they override the linked database's.

3. Redeploy.

Your app logs that DATABASE_URL is set but the connection goes to localhost.

The value is only a database name (like my_db) or a partial address. Drivers read a value without a host as "localhost".

Delete your DATABASE_URL in Variables. The linked database gives the full one, postgresql://user:password@host:5432/database. Redeploy.

The deploy stops with “Your database … is stopped, so your app can't reach it”.

You stopped it, or it was stopped because it grew past its plan's storage.

Start it from Databases. If it was stopped for storage, delete data or move to a plan with more storage first. Then deploy again.

Authentication fails, or the database name is wrong.

The code uses your local credentials (root with no password, a fixed database name).

Read every connection setting from the variables: DB_HOST, DB_PORT, DB_DATABASE, DB_USERNAME, DB_PASSWORD, or just DATABASE_URL.