学说撷取加入 [英] Doctrine fetch join

问题描述

首先我会举一些伪代码的例子，然后我将解释什么是问题。让我说我有两个实体User和Phonenumber。他们的关系是一对多的。在我的UserRepository中，我可以这样做：

  class UserRepository 
 {
 public function getUser id，$ type）
 {
 $ users = $ this-> createQuery（SELECT u，p FROM User u JOIN u.phonenumbers p 
 WHERE u.id =：id AND p .type =：type）
  - > setParameters（array（
'id'=> $ id，
'type'=> $ type，
） 
  - > getResult（）; 
 return $ users [0]; 
} 
} 
  

在我的应用程序中，如果我有这样的东西： p>

  $ user = $ userRepo-> getUser（1，'home'）; 
 var_dump（$ user-> getPhonenumbers（））; //这里phonenumbers集合是ok 
 
 $ user = $ userRepo> getUser（1，'work'）; 
 var_dump（$ user-> getPhonenumbers（））; //这里phonenumbers收藏是错误的。 
 //与前一个完全一样。 
  

所以我的问题是：是否可以使用提取连接（具有不同的条件）每次正确收集？

解决方案

获取加入和过滤集合并不是很好地协同工作。以下是您应该如何做：

  SELECT 
u，p 
 FROM 
用户u 
 JOIN 
 u.phonenumbers p 
 JOIN 
 u.phonenumbers p2 
 WHERE 
 u.id =：id 
 AND 
 p2 .type =：type 
  

这对第二个加入（而不是水合）应用过滤器 p2 ，这会导致正确的水合和过滤。

First I will give an example with some pseudo code and then I will explain what is the problem. Let me say I have two entities User and Phonenumber. Their relation is one-to-many. In my UserRepository I can have something like that:

class UserRepository
{
    public function getUser($id, $type)
    {
        $users = $this->createQuery("SELECT u, p FROM User u JOIN u.phonenumbers p
            WHERE u.id = :id AND p.type = :type")
            ->setParameters(array(
                'id' => $id,
                'type' => $type,
            ))
            ->getResult();
        return $users[0];
    }
}

In my app if I have something like:

$user = $userRepo->getUser(1, 'home');
var_dump($user->getPhonenumbers()); // here phonenumbers collection is ok

$user = $userRepo->getUser(1, 'work');
var_dump($user->getPhonenumbers()); // Here phonenumbers collection is wrong.
                                // It's exactly the same as the previous one.

So my questions is: Is it possible to use fetch join (with different criteria) and to get the proper collection each time?

解决方案

Fetch joining and filtering a collection are not things that work together quite well. Here's how you should do it:

SELECT 
    u, p 
FROM 
    User u 
JOIN 
    u.phonenumbers p
JOIN
    u.phonenumbers p2
WHERE 
    u.id = :id 
    AND 
    p2.type = :type

This applies filtering on the second joined (and not hydrated) p2, which results in correct hydration and filtering.

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