Suppose there are two tables.

Table X--
Columns:
     id         x_value

Table Y--
Columns:
     id        x_id      y_value

Now I dont want to define relationship in doctrine classes and i want to retrieve some records using these two tables using a query like this:

Select x_value from x, y where y.id="variable_z" and x.id=y.x_id;

I m not able to figure out how to write query like this in doctrine orm

EDIT:

Table structures:

Table 1:

CREATE TABLE IF NOT EXISTS `image` (
  `id` int(11) NOT NULL AUTO_INCREMENT, 
`random_name` varchar(255) NOT NULL,
 `user_id` int(11) NOT NULL,
  `community_id` int(11) NOT NULL,
  `published` varchar(1) NOT NULL,
  PRIMARY KEY (`id`)
 ) ENGINE=InnoDB  DEFAULT CHARSET=latin1 AUTO_INCREMENT=259 ;

Table 2:

  CREATE TABLE IF NOT EXISTS `users` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
   `city` varchar(20) DEFAULT NULL,
   `state` varchar(20) DEFAULT NULL,
   `school` varchar(50) DEFAULT NULL,
   PRIMARY KEY (`id`)
 ) ENGINE=InnoDB  DEFAULT CHARSET=latin1 AUTO_INCREMENT=20 ;

Query I am using:

        $q = new Doctrine_RawSql();

        $q  ->select('{u.*}, {img.*}')
        ->from('users u LEFT JOIN image img ON u.id = img.user_id')
        ->addComponent('u', 'Users u')
        ->addComponent('img', 'u.Image img')
        ->where("img.community_id='$community_id' AND img.published='y' AND u.state='$state' AND u.city='$city
        ->orderBy('img.id DESC')
        ->limit($count+12)  
        ->execute();        

Error I am getting:

 Fatal error: Uncaught exception 'Doctrine_Exception' with message 'Couldn't find class
 u' in C:\xampp\htdocs\fanyer\doctrine\lib\Doctrine\Table.php:290 Stack trace: #0 
 C:\xampp\htdocs\fanyer\doctrine\lib\Doctrine\Table.php(240): Doctrine_Table-   >initDefinition() #1 C:\xampp\htdocs\fanyer\doctrine\lib\Doctrine\Connection.php(1127): 
Doctrine_Table->__construct('u', Object(Doctrine_Connection_Mysql), true) #2 
C:\xampp\htdocs\fanyer\doctrine\lib\Doctrine\RawSql.php(425): Doctrine_Connection-
>getTable('u') #3 C:\xampp\htdocs\fanyer\doctrine\models\Image.php(33):    Doctrine_RawSql-
>addComponent('img', 'u.Image imga') #4   C:\xampp\htdocs\fanyer\community_images.php(31): 
  Image->get_community_images_gallery_filter(4, 0, 'AL', 'ALBERTVILLE') #5 {main} thrown      in 
    C:\xampp\htdocs\fanyer\doctrine\lib\Doctrine\Table.php  on line 290