Yii：无法获取关系

Question

我的模特：

零售项目：

public function relations()
{
        // NOTE: you may need to adjust the relation name and the related
        // class name for the relations automatically generated below.
        return array(
                    'retailItemDetail' => array(self::BELONGS_TO, 'Item', array('item_id' => 'id')),
        );
}

我的看法：

$criteria = new CDbCriteria();
//$criteria->condition= "item_id = $id";
$items = RetailItem::model()->findAll($criteria);

CVarDumper::dump($items[0],3,true);

结果：

......
[relations] => array()
......

为什么关系array() 是空的？

Answer 1

这里的例子：

//sql
CREATE TABLE transaction (
    id INT(11) NOT NULL AUTO_INCREMENT,
    userId INT(11) NULL DEFAULT NULL,
    PRIMARY KEY (id)
)
COLLATE=utf8_general_ci
ENGINE=InnoDB;

CREATE TABLE user (
    id INT(11) NOT NULL AUTO_INCREMENT,
    PRIMARY KEY (id)
)
COLLATE=utf8_general_ci
ENGINE=InnoDB;

INSERT INTO user (id) VALUES (1);
INSERT INTO user (id) VALUES (2);
INSERT INTO transaction (id, userId) VALUES (2, 1);
INSERT INTO transaction (userId) VALUES (1);

//models
class User2 extends CActiveRecord
{
    public function tableName()
    {
        return 'user';
    }
    //... etc
} 

class Transaction2 extends CActiveRecord
{
    public function tableName()
    {
        return 'transaction';
    }


    public function relations()
    {
        return array(
            'user' => array(self::BELONGS_TO, 'User2', 'userId'),
        );
    }
    //... etc
}

使用方法：

$test = Transaction2::model()->findAll();
echo '<pre>';
print_r($test[0]->user);
echo '</pre>';
die();