Question

上下文
我正在使用CakePHP 3.x，我正在尝试使用分页构建ORM查询。我有表用户，主题和领域。用户可以有很多主题但只有一个区域。这是db模型：

CREATE TABLE users (
id INT AUTO_INCREMENT PRIMARY KEY,
email VARCHAR(255) NOT NULL,
password VARCHAR(255) NOT NULL,
);
CREATE TABLE topics (
id INT AUTO_INCREMENT PRIMARY KEY,
user_id INT NOT NULL,
name VARCHAR(255),
description TEXT,
FOREIGN KEY user_key (user_id) REFERENCES users(id)
);
CREATE TABLE areas (
id INT AUTO_INCREMENT PRIMARY KEY,
title VARCHAR(255),
UNIQUE KEY (title)
);
CREATE TABLE users_areas (
user_id INT NOT NULL,
area_id INT NOT NULL,
PRIMARY KEY (user_id, area_id),
FOREIGN KEY area_key(area_id) REFERENCES areas(id),
FOREIGN KEY user_key(user_id) REFERENCES users(id)
);

我需要什么
我需要按照给定的区域过滤所有主题我正在尝试下一个：

//1. get the area from the url (OK)
$area = $this->request->getQuery('area');

//2. Get the area from db to get the id
$myarea = $this->Areas->find()->where(['title' => $area])->first();

//3. Get all the users related to the area given
$users = $this->Users->find()->matching('Areas', function ($q){
            return $q->where(['Areas.id' => $myarea->id]);
          });

//4. Get the Topics and Paginate
$topics = $this->paginate($this->Topics->find('all')->innerJoinWith('Users', function ($q){
          return $q->where(['User.id' => $myarea->id]);
        }));

//5. Set the topics (OK)
$this->set(compact('topics'));
$this->set('_serialize', ['topics']);

我遇到了大量错误，我不确定如何正确构建查询。

Answer 1

乍一看，至少有一个错误：

$myarea在匿名函数中是不可见的。

如果你想在lambda函数中使用$myarea，你应该从父范围继承这个变量：use($var)。

http://php.net/manual/en/functions.anonymous.php示例＃3

$users = $this->Users->find()->matching('Areas', function ($q) use ($myarea) {
     return $q->where(['Areas.id' => $myarea->id]);
});


$topics = $this->paginate($this->Topics->find('all')->innerJoinWith('Users', function ($q){
      return $q->where(['User.id' => $myarea->id]);
}));

CakePHP 3.x使用分页查询许多Table对象

1 个答案: