Question

我有4个模型，Application，Accommodation，Invoice和InvoiceItem

Invoice，Application和Accommodation所有人都有InvoiceItem

InvoiceItem belongsTo Application，Accommodation和Invoice

所有这一切的目的是使Invoice（来自InvoiceItem模型）的订单项可以与Accommodation或{{1}相关联} Application取决于InvoiceItem.foreign_id是InvoiceItem.class还是Accommodation

据我所知，这被称为多态关联。

不幸的是，当我使用递归设置为3（或设置为-1并使用containsable中指定的相应字段）执行Application时，我收到此MySQL错误：

$this->Invoice->find('all');

我不明白为什么Cake会尝试添加Error: SQLSTATE[42S22]: Column not found: 1054 Unknown column 'InvoiceItem.class' in 'where clause' SQL Query: SELECT `Application`.`id`, `Application`.`name`, `Application`.`created`, `Application`.`updated` FROM `applications` AS `Application` WHERE `Application`.`id` = 3786 AND `InvoiceItem`.`class` = 'Application'作为条件而不为InvoiceItem.class模型创建连接。

以下是我的模型（注意：为了便于阅读，我减少了每个字段的数量 - InvoiceItem和Application模型在现实中共享的字段非常少）：

住宿模式

Accommodation

应用程序模型

CREATE TABLE `accommodations` (
  `id` int(10) NOT NULL AUTO_INCREMENT,
  `name` varchar(255) COLLATE utf8_unicode_ci NOT NULL,
  `created` datetime NOT NULL,
  `updated` datetime NOT NULL,
  PRIMARY KEY (`id`)
)

<?php 
class Accommodation extends AppModel {
    var $name = 'Accommodation';
    var $hasMany = array(
        'InvoiceItem' => array(  
            'className' => 'InvoiceItem',
            'foreignKey' => 'foreign_id',
            'conditions' => array('InvoiceItem.class' => 'Accommodation'),
        )
    );
}
?>

InvoiceItem模型

CREATE TABLE `applications` (
  `id` int(10) NOT NULL AUTO_INCREMENT,
  `name` varchar(255) COLLATE utf8_unicode_ci NOT NULL,
  `created` datetime NOT NULL,
  `updated` datetime NOT NULL,
  PRIMARY KEY (`id`)
)

<?php 
class Application extends AppModel {
    var $name = 'Application';
    var $hasMany = array(
        'InvoiceItem' => array(  
            'className' => 'InvoiceItem',
            'foreignKey' => 'foreign_id',
            'conditions' => array('InvoiceItem.class' => 'Application'),
        )
    );
}
?>

发票型号

CREATE TABLE IF NOT EXISTS `invoice_items` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `class` varchar(30) COLLATE utf8_unicode_ci NOT NULL,
  `foreign_id` int(10) unsigned NOT NULL,
  `name` varchar(100) COLLATE utf8_unicode_ci NOT NULL,
  `created` datetime DEFAULT NULL,
  `modified` datetime DEFAULT NULL,
  PRIMARY KEY (`id`)
)

<?php 
class InvoiceItem extends AppModel {
    var $name = 'InvoiceItem';   
    var $belongsTo = array(
        'Accommodation' => array(
            'foreignKey' => 'foreign_id',
            'conditions' => array('InvoiceItem.class' => 'Accommodation')
        ),
        'Application' => array(
            'foreignKey' => 'foreign_id',
            'conditions' => array('InvoiceItem.class' => 'Application')
        ),
        'Invoice' => array(
            'className' => 'Invoice',
            'foreignKey' => 'invoice_id',
        ),
    );
}
?>

我正在使用CakePHP 2.4.0

Answer 1

类InvoiceItem扩展AppModel，并且不绑定belongsTo。

class InvoiceItem extends AppModel {
    var $name = 'InvoiceItem';   
    var $belongsTo = null
}

您可以在运行时根据内容

为InvoiceItem分配合适的belongsTo

$this->InvoiceItem->bindModel(array( 'belongsTo' => array(...) ) )

MySQL错误与CakePHP中直接的多态关联

1 个答案: