Polymorphic - example usage

app_model.php

<?php  
class AppModel extends Model {
    function __construct($id = false, $table = null, $ds = null) { 
        parent::__construct($id, $table, $ds); 
        if (isset($this->hasMany['Note'])) { 
            $this->hasMany['Note']['conditions']['Note.class'] = $this->name; 
            $this->hasMany['Note']['foreignKey'] = 'foreign_id'; 
        } 
    }
}

customer.php

<?php  
class Customer extends AppModel {
    var $hasMany = array('Note');
}

note.php

<?php
class Note extends AppModel {
	var $actsAs = array('Polymorphic.Polymorphic');
	var $belongsTo = array('Customer');
}