hasOne('Order', array('id' => 'order_id')); } public function getItem() { return $this->hasOne('Item', array('id' => 'item_id')); } public static function getTableSchema() { return new RecordSchema(array( 'name' => 'order_item', 'primaryKey' => array('order_id', 'item_id'), 'columns' => array( 'order_id' => 'integer', 'item_id' => 'integer', 'quantity' => 'integer', 'subtotal' => 'decimal', ) )); } }