Question

数据库中的每个Order都有一个product_id。每个订单只有一个Product。

从ProductsController开始，我希望显示所有产品，并在每个产品旁边显示已订购的次数。我需要包含一个条件，以排除任何包含deleted = 0

的产品

Answer 1

将order_count字段添加到Product表并按原样修改订单模型

class Order extends AppModel {
    public $belongsTo = array(
        'Product' => array(
            'counterCache' => true,
            'counterScope' => array('Product.deleted' => 0)
        )
    );
}

Answer 2

此查询应返回您需要的结果。根据需要调整条件，附加字段等。

$data = $this->Order->find('all',array( 
   'fields'=>array(
       'COUNT(Product.id)as Count',
       'Product.id','Product.name'
   ), 
   'group'=>array(
       'Product.id'
   ), 
   'contain'=>'Product' 
));

Answer 3

一个简单的find('count')就足够了（此查找操作的详细信息在the Cookbook中）：

// Get a list of all the active products
$products = $this->Product->find('list', array(
    'conditions' => array('Product.deleted' => 0)
));

// Loop over the products
foreach($products as $product_id => $product) {
    $count = $this->Product->Order->find('count', array(
        'conditions' => array('Order.product_id' => $product_id)
    ));
    echo "There were " . $count . " orders for " . $product;
}

正如马克所建议的那样，GROUP BY也应该通过一次查找来完成这一过程并简化过程。

$count = $this->Product->Order->find('count', array(
    'conditions' => array(
        'Order.product_id' => $product_id,
        'Product.deleted' => 0
    ),
    'group' => array('Order.product_id')
));

计算每件产品的订购次数

3 个答案: