使用 CakePHP 查询时得到错误的结果

Question

我正在尝试获取 Low stock > Stock 的产品。

为什么我在 CakePHP 查询中得到错误的结果？

使用 CakePHP 自定义查询可以正常工作。但是默认分页查询结果是错误的。

我在产品和类别模型之间建立了关联。

控制器代码：

$condition = array('Product.status =' => 1, 'Product.is_deleted !=' => 1, 
'Product.low_stock_alert != ' => 0, 'Product.low_stock_alert >' => 'Product.stock');

    $this->paginate = array('fields' => array('Product.id', 'Product.name',
'Product.code', 'Product.stock_type','Product.low_stock_alert',
'Product.stock','category.name'),'conditions' => $condition, 'limit' => Configure::read('LIST_PROD_NUM_RECORDS'),'order' => 'Product.id ASC');

查询生成：

SELECT `Product`.`id`, `Product`.`name`, `Product`.`code`, `Product`.`stock_type`,
`Product`.`stock`, `category`.`name` FROM `shopping`.`products` AS `Product` LEFT 
JOIN `shopping`.`categories` AS `Category` ON (`Product`.`category_id` = 
`Category`.`id`) LEFT JOIN `shopping`.`users` AS `AddedBy` ON (`Product`.`added_by` 
= `AddedBy`.`id`) LEFT JOIN `shopping`.`users` AS `ModifiedBy` ON 
(`Product`.`modified_by` = `ModifiedBy`.`id`) WHERE `Product`.`status` = 1 AND 
`Product`.`is_deleted` != 1 AND `Product`.`low_stock_alert` != 0 AND 
`Product`.`low_stock_alert` > 'Product.stock' ORDER BY `Product`.`id` ASC LIMIT 100

模型 -> Product.php

class Product extends AppModel {

    public $name = 'Product';
    public $cacheQueries = false;
    public $actsAs = array('Containable');
    public $belongsTo = array(
        'Category' => array(
            'className' => 'Category',
            'foreignKey' => 'category_id',
            'fields' => array('name', 'description', 'stock_type', 'qrt_per', 'half_per', 'three_forth_per')
        ),
        'AddedBy' => array(
            'className' => 'User',
            'foreignKey' => 'added_by',
            'fields' => array('first_name', 'last_name', 'email')
        ),
        'ModifiedBy' => array(
            'className' => 'User',
            'foreignKey' => 'modified_by',
            'fields' => array('first_name', 'last_name', 'email')
        )
    );
}

模型 -> Category.php

class Category extends AppModel {
    var $name = 'Category';
    public $cacheQueries = false;
    public $belongsTo = array(
        'AddedBy' => array(
            'className' => 'User',
            'foreignKey' => 'added_by',
            'fields' => array('first_name', 'last_name', 'email')
        ),
        'ModifiedBy' => array(
            'className' => 'User',
            'foreignKey' => 'modified_by',
            'fields' => array('first_name', 'last_name', 'email')
        )
    );
    public $hasMany = array(
        'Product' => array(
            'className' => 'Product',
            'order' => 'Product.created DESC'
        )
    );
}

错误结果：

但是通过下面的自定义查询，我得到了准确的结果：

 $data = $this->Product->Query("SELECT products.*, categories.name, categories.description, categories.stock_type, categories.qrt_per, categories.half_per, categories.three_forth_per, AddedBy.first_name, AddedBy.last_name, AddedBy.email, ModifiedBy.first_name, ModifiedBy.last_name, ModifiedBy.email FROM sunnaair_kaziDB.products AS products LEFT JOIN sunnaair_kaziDB.categories AS categories ON (products.category_id = categories.id) LEFT JOIN sunnaair_kaziDB.users AS AddedBy ON (products.added_by = AddedBy.id) LEFT JOIN sunnaair_kaziDB.users AS ModifiedBy ON (products.modified_by = ModifiedBy.id) WHERE products.status = 1 AND products.is_deleted != 1 AND products.low_stock_alert != 0 AND products.low_stock_alert > products.stock ORDER BY products.id ASC LIMIT 50");

Answer 1

您的问题在于这种情况：

'Product.low_stock_alert >' => 'Product.stock'

在 Cake 中，'Product.stock' 不是作为表名读取的，而是作为文字字符串读取的。请查看生成的 SQL 中的细微错误：

AND `Product`.`low_stock_alert` > 'Product.stock'

要修复它，请尝试将条件更改为：

'Product.low_stock_alert > Product.stock'

所以整行变成：

 $condition = array('Product.status =' => 1, 'Product.is_deleted !=' => 1, 
'Product.low_stock_alert != ' => 0, 'Product.low_stock_alert > Product.stock');

记住以下几点：=> 用于转义。在比较列与列时不要使用它。对于这些情况，您甚至可以直接使用 => 进行转储，因为这里没有用于 SQL 注入攻击的向量。