private static function parseDatabaseUrlScheme(array $url, array $params) : array
    {
        if (isset($url['scheme'])) {
            // The requested driver from the URL scheme takes precedence
            // over the default custom driver from the connection parameters (if any).
            unset($params['driverClass']);

            // URL schemes must not contain underscores, but dashes are ok
            $driver = str_replace('-', '_', $url['scheme']);
            assert(is_string($driver));

            // The requested driver from the URL scheme takes precedence over the
            // default driver from the connection parameters. If the driver is
            // an alias (e.g. "postgres"), map it to the actual name ("pdo-pgsql").
            // Otherwise, let checkParams decide later if the driver exists.
            $params['driver'] = self::$driverSchemeAliases[$driver] ?? $driver;

            return $params;
        }

        // If a schemeless connection URL is given, we require a default driver or default custom driver
        // as connection parameter.
        if (! isset($params['driverClass']) && ! isset($params['driver'])) {
            throw DBALException::driverRequired($params['url']);
        }

        return $params;
    }