gistfile1.php

<?php
'relationships' => array(
    /* regular one-to-many */
    'contact_direct_reports' => array(
		'left' => array('module' => 'Contacts', 'link' => 'reports_to_link'),
		'right' => array('module' => 'Contacts', 'link' => 'direct_reports'),
    ),
    /* one-to-many with fields */			
    'accounts_contacts' => array( 
	'left' => array('module' => 'Accounts', 'id' = 'account_id', 'link' => 'contacts'),
	'right' => array('module' => 'Contacts', 'id' = 'contact_id', 'link' => 'accounts'),
	 'fields' => array(
	 	'id'=>array('type'=>'id'),
	 	'contact_role'=> array('type'=>'varchar'),
	 )
    ),
    /* many-to-many */
    'contacts_opportunties'=> array(
	'left'=>array('module'=>'Opportunities', 'id'=>'opportunity_id', 'link' => 'contacts'),
	'right'=>array('module'=>'Contacts', 'id'=>'contact_id', 'link' => 'opportunities'),
	'fields'= array(
		'id'=>array('type'=>'id'),
		'contact_role'=> array('type'=>'varchar'),
	),
    ),