Database connection

Symptom: installer or app cannot connect (SQLSTATE, “Access denied for user”, unknown database).

Likely cause: wrong host/user/password; database missing; socket vs TCP.

Check

1. Credentials in .env (DB_HOST, DB_DATABASE, DB_USERNAME, DB_PASSWORD). Host 127.0.0.1 vs localhost — localhost often means a Unix socket the PHP user cannot see.
2. The database exists. Creating .env does not create the schema.
3. After ENV changes: from backend/ run php artisan config:clear.

Fix

• Create the database; fix .env; retry the installer or php artisan migrate (pending only).
• Never migrate:fresh to “retry” production. Never db:wipe.
• Do not paste database passwords into public tickets.

Related: Installer, Requirements.