如何在cakephp2.x中的find请求中使用Union

我需要知道如何在cakephp中使用Union条件和find请求，因为我必须在同一字段中选择具有多个条件的数据

我有3种型号：

class Zone extends AppModel
{
  var $name = 'Zone';
  var $belongsTo = "Fournisseur";
}

及

及

我想从ZoneTaif获取数据，条件如下：

conditions 1 : ZoneTarif.poids = 40  and ZoneTarif.zone_id=1
conditions 2 : ZoneTarif.poids = 50  and ZoneTarif.zone_id=7
conditions 3 : ZoneTarif.poids = 90  and ZoneTarif.zone_id=10
.........etc.

因此，我如何将Union与find结合使用：

$this->ZoneTarif->recursive = 2;    
$data1 = $this->ZoneTarif->find('all',array('conditions'=>array('ZoneTarif.poids'=>40,'ZoneTarif.zone_id IN'=>1)));
    $data2 = $this->ZoneTarif->find('all',array('conditions'=>array('ZoneTarif.poids'=>50,'ZoneTarif.zone_id IN'=>7)));

使用简单查询时，我丢失了所有连接和表别名：

$v =  $this->ZoneTarif->query("SELECT * FROM zone_tarifs INNER JOIN zones 
                                              WHERE zone_id = 6 and poids = 10 and zones.id = zone_tarifs.zone_id
                                              UNION
                                              SELECT * FROM zone_tarifs INNER JOIN zones 
                                              WHERE zone_id = 4 and poids = 40 and zones.id = zone_tarifs.zone_id
                                            ");

谢谢你的帮助

$this->ZoneTarif->recursive = 2;    
$data1 = $this->ZoneTarif->find('all',array('conditions'=>array('ZoneTarif.poids'=>40,'ZoneTarif.zone_id IN'=>1)));
    $data2 = $this->ZoneTarif->find('all',array('conditions'=>array('ZoneTarif.poids'=>50,'ZoneTarif.zone_id IN'=>7)));

$v =  $this->ZoneTarif->query("SELECT * FROM zone_tarifs INNER JOIN zones 
                                              WHERE zone_id = 6 and poids = 10 and zones.id = zone_tarifs.zone_id
                                              UNION
                                              SELECT * FROM zone_tarifs INNER JOIN zones 
                                              WHERE zone_id = 4 and poids = 40 and zones.id = zone_tarifs.zone_id
                                            ");