CakePHP：findById()with Containable不返回预期的关联

这是我的模特：

class Question extends AppModel {


public $hasMany = array(
    'CaseQuestions' => array('className'=>'Question', 'foreignKey'=>'parent_id')
);

public $hasOne = array(
    'CaseStudy' => array('className'=>'Question', 'foreignKey'=>'parent_id')
);

这是我的控制器中的动作：

public function admin_delete_case_question($question_id) {
        $this->Question->Behaviors->load('Containable');
        $this->Question->contain( array('CaseStudy'));
        $question = $this->Question->findById($question_id );
        debug($question); 
        exit;

上面的调试返回如下内容：

array(
    'Question' => array(
        'id' => '78',
        'nickname' => '',
        'content' => 'sdgsdfgs',
        'type' => 'CQ',
        'option1' => 'sdfgsdfg',
        'option2' => '',
        'option3' => '',
        'option4' => '',
        'time' => '-1',
        'difficulty' => '0.0000',
        'slope' => '0.0000',
        'chance' => '0',
        'experiment' => false,
        'created' => '2013-05-02 16:30:29',
        'modified' => '2013-05-02 16:30:29',
        'status' => null,
        'perm_id' => '76',
        'notes' => null,
        'is_deleted' => false,
        'answer_id' => '0',
        'parent_id' => '77',
        'order' => null
    ),
    'CaseStudy' => array(
        'id' => null,
        'nickname' => null,
        'content' => null,
        'type' => null,
        'option1' => null,
        'option2' => null,
        'option3' => null,
        'option4' => null,
        'time' => null,
        'difficulty' => null,
        'slope' => null,
        'chance' => null,
        'experiment' => null,
        'created' => null,
        'modified' => null,
        'status' => null,
        'perm_id' => null,
        'notes' => null,
        'is_deleted' => null,
        'answer_id' => null,
        'parent_id' => null,
        'order' => null
    )
)

我不明白为什么CaseStudy数组都是NULL,因为当我在DB中查看该记录(id 77)时,所有数据都是正确的.我究竟做错了什么？

解决方法:

在你的例子中…问题有一个CaseStudy;这意味着问题是父母.

根据您的数据,您的问题有一个parent_id,所以我假设您实际上意味着CaseStudy是父,而Question是孩子.看起来您的关联实际上是倒退的(通常父节点不会有parent_id).

用belongsTo替换你的hasOne关联：

public $belongsTo = array(
      'CaseStudy' => array('className'=>'Question', 'foreignKey'=>'parent_id')
);

这将确保CaseStudy是父级,而Question是孩子.

通过它当前设置的方式,CakePHP正在尝试寻找一个父类与您的Question.id相等的CaseStudy;因为你的数据库中没有任何类似的数据,CakePHP找不到任何内容并返回空值.
实际上,CaseStudy实际上是父,而Question的parent_id等于CaseStudy.id

标签：cakephp-2-0,cakephp-2-1,php,mysql,cakephp
来源： https://codeday.me/bug/20190901/1779639.html