$databases = array (
  'default' =>
  array (
    'default' =>
    array (
      'database' => 'db_name1',
      'username' => 'xxxx',
      'password' => 'xxxx',
      'host' => 'host1',
      'port' => '3306',
      'driver' => 'mysql',
      'prefix' => '',
    ),
  ),
  'mportal' =>
  array(
    'default' =>
    array (
      'database' => 'db_name2',
      'username' => 'zzzzz',
      'password' => 'zzzzz',
      'host' => 'host2',
      'port' => '3306',
      'driver' => 'mysql',
      'prefix' => '',
    ),
  ),
'ora_db' =>
    array(
    'default' =>
        array (
        'database' => 'ora_dbname',
                'username' => 'yyyyyy',
                'password' => 'yyyyyy',
                'host' => 'ora_db_host_name/service_name',
                'port' => '1521',
                'driver' => 'oracle',
                'prefix' => '',
            ),
    ),
);