Create mySQL database

Go to https://phpmyadmin.staging.ext.dev/ and log in with your credentials.

Go to "User Accounts" and click "Add a user account".

Set a username and a (random and secure) password. Use the project name as username. Make sure to set "Native mySQL authentication" in dropdown.

Import project database

First copy the mysqldump of the project database to /var/www on the staging server.

Then import the dump.

mysql -u{username} -p {dbname} < {filename}

Make sure to replace {username}, {dbname} and {filename} with the appropriate values. Enter the password defined in the first step, when asked.

Configure database in AdditionalConfiguration.php

Now edit the file /var/www/deployments/{projectname}.staging.ext.dev/shared/public/typo3conf/AdditionalConfiguration.php

<?php

$GLOBALS['TYPO3_CONF_VARS']['DB'] = [
        'Connections' => [
            'Default' => [
                'charset' => 'utf8',
                'dbname' => '{dbname}',
                'driver' => 'mysqli',
                'host' => 'localhost',
                'password' => '{password}',
                'user' => '{username}',
            ],
        ],
    ];

Make sure to replace {dbname}, {password} and {username} with the values defined when creating the database.